RESUMO
BACKGROUND: Seasonal vaccination with the RTS,S/AS01E vaccine combined with seasonal malaria chemoprevention (SMC) prevented malaria in young children more effectively than either intervention given alone over a 3 year period. The objective of this study was to establish whether the added protection provided by the combination could be sustained for a further 2 years. METHODS: This was a double-blind, individually randomised, controlled, non-inferiority and superiority, phase 3 trial done at two sites: the Bougouni district and neighbouring areas in Mali and Houndé district, Burkina Faso. Children who had been enrolled in the initial 3-year trial when aged 5-17 months were initially randomly assigned individually to receive SMC with sulphadoxine-pyrimethamine and amodiaquine plus control vaccines, RTS,S/AS01E plus placebo SMC, or SMC plus RTS,S/AS01E. They continued to receive the same interventions until the age of 5 years. The primary trial endpoint was the incidence of clinical malaria over the 5-year trial period in both the modified intention-to-treat and per-protocol populations. Over the 5-year period, non-inferiority was defined as a 20% increase in clinical malaria in the RTS,S/AS01E-alone group compared with the SMC alone group. Superiority was defined as a 12% difference in the incidence of clinical malaria between the combined and single intervention groups. The study is registered with ClinicalTrials.gov, NCT04319380, and is complete. FINDINGS: In April, 2020, of 6861 children originally recruited, 5098 (94%) of the 5433 children who completed the initial 3-year follow-up were re-enrolled in the extension study. Over 5 years, the incidence of clinical malaria per 1000 person-years at risk was 313 in the SMC alone group, 320 in the RTS,S/AS01E-alone group, and 133 in the combined group. The combination of RTS,S/AS01E and SMC was superior to SMC (protective efficacy 57·7%, 95% CI 53·3 to 61·7) and to RTS,S/AS01E (protective efficacy 59·0%, 54·7 to 62·8) in preventing clinical malaria. RTS,S/AS01E was non-inferior to SMC (hazard ratio 1·03 [95% CI 0·95 to 1·12]). The protective efficacy of the combination versus SMC over the 5-year period of the study was very similar to that seen in the first 3 years with the protective efficacy of the combination versus SMC being 57·7% (53·3 to 61·7) and versus RTS/AS01E-alone being 59·0% (54·7 to 62·8). The comparable figures for the first 3 years of the study were 62·8% (58·4 to 66·8) and 59·6% (54·7 to 64·0%), respectively. Hospital admissions for WHO-defined severe malaria were reduced by 66·8% (95% CI 40·3 to 81·5), for malarial anaemia by 65·9% (34·1 to 82·4), for blood transfusion by 68·1% (32·6 to 84·9), for all-cause deaths by 44·5% (2·8 to 68·3), for deaths excluding external causes or surgery by 41·1% (-9·2 to 68·3), and for deaths from malaria by 66·8% (-2·7 to 89·3) in the combined group compared with the SMC alone group. No safety signals were detected. INTERPRETATION: Substantial protection against malaria was sustained over 5 years by combining seasonal malaria vaccination with seasonal chemoprevention, offering a potential new approach to malaria control in areas with seasonal malaria transmission. FUNDING: UK Joint Global Health Trials and PATH's Malaria Vaccine Initiative (through a grant from the Bill & Melinda Gates Foundation). TRANSLATION: For the French translation of the abstract see Supplementary Materials section.
Assuntos
Vacinas Antimaláricas , Malária Falciparum , Malária , Criança , Humanos , Lactente , Pré-Escolar , Mali/epidemiologia , Burkina Faso/epidemiologia , Estações do Ano , Malária/epidemiologia , Malária/prevenção & controle , Vacinação , Quimioprevenção , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controleRESUMO
BACKGROUND: A recent trial in Burkina Faso and Mali showed that combining seasonal RTS,S/AS01E malaria vaccination with seasonal malaria chemoprevention (SMC) substantially reduced the incidence of uncomplicated and severe malaria in young children compared to either intervention alone. Given the possible negative effect of malaria on nutrition, the study investigated whether these children also experienced lower prevalence of acute and chronic malnutrition. METHODS: In Burkina Faso and Mali 5920 children were randomized to receive either SMC alone, RTS,S/AS01E alone, or SMC combined with RTS,S/AS01E for three malaria transmission seasons (2017-2019). After each transmission season, anthropometric measurements were collected from all study children at a cross-sectional survey and used to derive nutritional status indicators, including the binary variables wasted and stunted (weight-for-height and height-for-age z-scores below - 2, respectively). Binary and continuous outcomes between treatment groups were compared by Poisson and linear regression. RESULTS: In 2017, compared to SMC alone, the combined intervention reduced the prevalence of wasting by approximately 12% [prevalence ratio (PR) = 0.88 (95% CI 0.75, 1.03)], and approximately 21% in 2018 [PR = 0.79 (95% CI 0.62, 1.01)]. Point estimates were similar for comparisons with RTS,S/AS01E, but there was stronger evidence of a difference. There was at least a 30% reduction in the point estimates for the prevalence of severe wasting in the combined group compared to the other two groups in 2017 and 2018. There was no difference in the prevalence of moderate or severe wasting between the groups in 2019. The prevalence of stunting, low-MUAC-for-age or being underweight did not differ between groups for any of the three years. The prevalence of severe stunting was higher in the combined group compared to both other groups in 2018, and compared to RTS,S/AS01E alone in 2017; this observation does not have an obvious explanation and may be a chance finding. Overall, malnutrition was very common in this cohort, but declined over the study as the children became older. CONCLUSIONS: Despite a high burden of malnutrition and malaria in the study populations, and a major reduction in the incidence of malaria in children receiving both interventions, this had only a modest impact on nutritional status. Therefore, other interventions are needed to reduce the high burden of malnutrition in these areas. TRIAL REGISTRATION: https://www.clinicaltrials.gov/ct2/show/NCT03143218 , registered 8th May 2017.
Assuntos
Antimaláricos , Malária , Antimaláricos/uso terapêutico , Burkina Faso/epidemiologia , Quimioprevenção , Criança , Pré-Escolar , Estudos Transversais , Humanos , Lactente , Malária/tratamento farmacológico , Malária/epidemiologia , Malária/prevenção & controle , Mali/epidemiologia , Estado Nutricional , Estações do Ano , VacinaçãoRESUMO
BACKGROUND: A trial in African children showed that combining seasonal vaccination with the RTS,S/AS01E vaccine with seasonal malaria chemoprevention reduced the incidence of uncomplicated and severe malaria compared with either intervention given alone. Here, we report on the anti-circumsporozoite antibody response to seasonal RTS,S/AS01E vaccination in children in this trial. METHODS: Sera from a randomly selected subset of children collected before and 1 month after 3 priming doses of RTS,S/AS01E and before and 1 month after 2 seasonal booster doses were tested for anti-circumsporozoite antibodies using enzyme-linked immunosorbent assay. The association between post-vaccination antibody titer and incidence of malaria was explored. RESULTS: A strong anti-circumsporozoite antibody response to 3 priming doses of RTS,S/AS01E was seen (geometric mean titer, 368.9 enzyme-linked immunosorbent assay units/mL), but titers fell prior to the first booster dose. A strong antibody response to an annual, pre-malaria transmission season booster dose was observed, but this was lower than after the primary vaccination series and lower after the second than after the first booster dose (ratio of geometric mean rise, 0.66; 95% confidence interval [CI], .57-.77). Children whose antibody response was in the upper tercile post-vaccination had a lower incidence of malaria during the following year than children in the lowest tercile (hazard ratio, 0.43; 95% CI, .28-.66). CONCLUSIONS: Seasonal vaccination with RTS,S/AS01E induced a strong booster antibody response that was lower after the second than after the first booster dose. The diminished antibody response to the second booster dose was not associated with diminished efficacy. CLINICAL TRIALS REGISTRATION: NCT03143218.
Assuntos
Vacinas Antimaláricas , Malária Falciparum , Malária , Formação de Anticorpos , Criança , Humanos , Lactente , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Plasmodium falciparum , Estações do Ano , VacinaçãoRESUMO
BACKGROUND: Malaria control remains a challenge in many parts of the Sahel and sub-Sahel regions of Africa. METHODS: We conducted an individually randomized, controlled trial to assess whether seasonal vaccination with RTS,S/AS01E was noninferior to chemoprevention in preventing uncomplicated malaria and whether the two interventions combined were superior to either one alone in preventing uncomplicated malaria and severe malaria-related outcomes. RESULTS: We randomly assigned 6861 children 5 to 17 months of age to receive sulfadoxine-pyrimethamine and amodiaquine (2287 children [chemoprevention-alone group]), RTS,S/AS01E (2288 children [vaccine-alone group]), or chemoprevention and RTS,S/AS01E (2286 children [combination group]). Of these, 1965, 1988, and 1967 children in the three groups, respectively, received the first dose of the assigned intervention and were followed for 3 years. Febrile seizure developed in 5 children the day after receipt of the vaccine, but the children recovered and had no sequelae. There were 305 events of uncomplicated clinical malaria per 1000 person-years at risk in the chemoprevention-alone group, 278 events per 1000 person-years in the vaccine-alone group, and 113 events per 1000 person-years in the combination group. The hazard ratio for the protective efficacy of RTS,S/AS01E as compared with chemoprevention was 0.92 (95% confidence interval [CI], 0.84 to 1.01), which excluded the prespecified noninferiority margin of 1.20. The protective efficacy of the combination as compared with chemoprevention alone was 62.8% (95% CI, 58.4 to 66.8) against clinical malaria, 70.5% (95% CI, 41.9 to 85.0) against hospital admission with severe malaria according to the World Health Organization definition, and 72.9% (95% CI, 2.9 to 92.4) against death from malaria. The protective efficacy of the combination as compared with the vaccine alone against these outcomes was 59.6% (95% CI, 54.7 to 64.0), 70.6% (95% CI, 42.3 to 85.0), and 75.3% (95% CI, 12.5 to 93.0), respectively. CONCLUSIONS: Administration of RTS,S/AS01E was noninferior to chemoprevention in preventing uncomplicated malaria. The combination of these interventions resulted in a substantially lower incidence of uncomplicated malaria, severe malaria, and death from malaria than either intervention alone. (Funded by the Joint Global Health Trials and PATH; ClinicalTrials.gov number, NCT03143218.).
Assuntos
Amodiaquina/uso terapêutico , Antimaláricos/uso terapêutico , Vacinas Antimaláricas , Malária Falciparum/prevenção & controle , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Antimaláricos/efeitos adversos , Burkina Faso/epidemiologia , Quimioprevenção , Terapia Combinada , Método Duplo-Cego , Combinação de Medicamentos , Quimioterapia Combinada , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Vacinas Antimaláricas/administração & dosagem , Vacinas Antimaláricas/efeitos adversos , Malária Falciparum/epidemiologia , Malária Falciparum/mortalidade , Masculino , Mali/epidemiologia , Estações do Ano , Convulsões Febris/etiologiaRESUMO
BACKGROUND: Malaria and malnutrition remain major problems in Sahel countries, especially in young children. The direct effect of malnutrition on malaria remains poorly understood, and may have important implications for malaria control. In this study, nutritional status and the association between malnutrition and subsequent incidence of symptomatic malaria were examined in children in Burkina Faso and Mali who received either azithromycin or placebo, alongside seasonal malaria chemoprevention. METHODS: Mid-upper arm circumference (MUAC) was measured in all 20,185 children who attended a screening visit prior to the malaria transmission season in 2015. Prior to the 2016 malaria season, weight, height and MUAC were measured among 4149 randomly selected children. Height-for-age, weight-for-age, weight-for-height, and MUAC-for-age were calculated as indicators of nutritional status. Malaria incidence was measured during the following rainy seasons. Multivariable random effects Poisson models were created for each nutritional indicator to study the effect of malnutrition on clinical malaria incidence for each country. RESULTS: In both 2015 and 2016, nutritional status prior to the malaria season was poor. The most prevalent form of malnutrition in Burkina Faso was being underweight (30.5%; 95% CI 28.6-32.6), whereas in Mali stunting was most prevalent (27.5%; 95% CI 25.6-29.5). In 2016, clinical malaria incidence was 675 per 1000 person-years (95% CI 613-744) in Burkina Faso, and 1245 per 1000 person-years (95% CI 1152-1347) in Mali. There was some evidence that severe stunting was associated with lower incidence of malaria in Mali (RR 0.81; 95% CI 0.64-1.02; p = 0.08), but this association was not seen in Burkina Faso. Being moderately underweight tended to be associated with higher incidence of clinical malaria in Burkina Faso (RR 1.27; 95% CI 0.98-1.64; p = 0.07), while this was the case in Mali for moderate wasting (RR 1.27; 95% CI 0.98-1.64; p = 0.07). However, these associations were not observed in severely affected children, nor consistent between countries. MUAC-for-age was not associated with malaria risk. CONCLUSIONS: Both malnutrition and malaria were common in the study areas, high despite high coverage of seasonal malaria chemoprevention and long-lasting insecticidal nets. However, no strong or consistent evidence was found for an association between any of the nutritional indicators and the subsequent incidence of clinical malaria.
Assuntos
Antimaláricos/administração & dosagem , Azitromicina/administração & dosagem , Malária/epidemiologia , Desnutrição/epidemiologia , Estado Nutricional , Burkina Faso/epidemiologia , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Malária/transmissão , Masculino , Mali/epidemiologia , Desnutrição/classificação , Estações do AnoRESUMO
BACKGROUND: Mass drug administration (MDA) with azithromycin (AZ) is being considered as a strategy to promote child survival in sub-Saharan Africa, but the mechanism by which AZ reduces mortality is unclear. To better understand the nature and extent of protection provided by AZ, we explored the profile of protection by time since administration, using data from a household-randomized, placebo-controlled trial in Burkina Faso and Mali. METHODS: Between 2014 and 2016, 30 977 children aged 3-59 months received seasonal malaria chemoprevention (SMC) with sulfadoxine-pyrimethamine plus amodiaquine and either AZ or placebo monthly, on 4 occasions each year. Poisson regression with gamma-distributed random effects, accounting for the household randomization and within-individual clustering of illness episodes, was used to compare incidence of prespecified outcomes between SMC+AZ versus SMC+placebo groups in fixed time strata post-treatment. The likelihood ratio test was used to assess evidence for a time-treatment group interaction. RESULTS: Relative to SMC+placebo, there was no evidence of protection from SMC+AZ against hospital admissions and deaths. Additional protection from SMC+AZ against malaria was confined to the first 2 weeks post-administration (protective efficacy (PE): 24.2% [95% CI: 17.8%, 30.1%]). Gastroenteritis and pneumonia were reduced by 29.9% [21.7; 37.3%], and 34.3% [14.9; 49.3%], respectively, in the first 2 weeks postadministration. Protection against nonmalaria fevers with a skin condition persisted up to 28 days: PE: 46.3% [35.1; 55.6%]. CONCLUSIONS: The benefits of AZ-MDA are broad-ranging but short-lived. To maximize impact, timing of AZ-MDA must address the challenge of targeting asynchronous morbidity and mortality peaks from different causes.
Assuntos
Antimaláricos , Malária , Antimaláricos/uso terapêutico , Azitromicina/uso terapêutico , Burkina Faso/epidemiologia , Quimioprevenção , Pré-Escolar , Combinação de Medicamentos , Humanos , Lactente , Malária/tratamento farmacológico , Malária/epidemiologia , Malária/prevenção & controle , Mali/epidemiologia , Estações do AnoRESUMO
INTRODUCTION: Seasonal malaria chemoprevention (SMC), with sulphadoxine-pyrimethamine plus amodiaquine (SP+AQ) is effective but does not provide complete protection against clinical malaria. The RTS,S/AS01E malaria vaccine provides a high level of protection shortly after vaccination, but this wanes rapidly. Such a vaccine could be an alternative or additive to SMC. This trial aims to determine whether seasonal vaccination with RTS,S/AS01E vaccine could be an alternative to SMC and whether a combination of the two interventions would provide added benefits. METHODS AND ANALYSIS: This is an individually randomised, double-blind, placebo-controlled trial. 5920 children aged 5-17 months were enrolled in April 2017 in Mali and Burkina Faso. Children in group 1 received three priming doses of RTS,S/AS01E vaccine before the start of the 2017 malaria transmission season and a booster dose at the beginning of two subsequent transmission seasons. In addition, they received SMC SP+AQ placebo on four occasions each year. Children in group 2 received three doses of rabies vaccine in year 1 and hepatitis A vaccine in years 2 and 3 together with four cycles of SMC SP+AQ each year. Children in group 3 received RTS,S/AS01E vaccine and four courses of SMC SP+AQ. Incidence of clinical malaria is determined by case detection at health facilities. Weekly active surveillance for malaria is undertaken in a randomly selected subset of children. The prevalence of malaria is measured in surveys at the end of each transmission season. The primary endpoint is the incidence of clinical malaria confirmed by a positive blood film with a minimum parasite density of 5000 /µL. Primary analysis will be by modified intention to treat defined as children who have received the first dose of the malaria or control vaccine. ETHICS AND DISSEMINATION: The protocol was approved by the national ethics committees of Mali and Burkina Faso and the London School of Hygiene and Tropical Medicine. The results will be presented to all stakeholders and published in open access journals. TRIAL REGISTRATION NUMBER: NCT03143218; Pre-results.
Assuntos
Antimaláricos , Vacinas Antimaláricas , Malária Falciparum , Malária , Antimaláricos/uso terapêutico , Burkina Faso/epidemiologia , Quimioprevenção , Criança , Ensaios Clínicos Fase III como Assunto , Humanos , Lactente , Londres , Malária/tratamento farmacológico , Malária/epidemiologia , Malária/prevenção & controle , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Mali , Ensaios Clínicos Controlados Aleatórios como Assunto , Estações do Ano , VacinaçãoRESUMO
BACKGROUND: Seasonal malaria chemoprevention (SMC) is now widely deployed in the Sahel, including several countries that are major contributors to the global burden of malaria. Consequently, it is important to understand whether SMC continues to provide a high level of protection and how SMC might be improved. SMC was evaluated using data from a large, household-randomised trial in Houndé, Burkina Faso and Bougouni, Mali. METHODS AND FINDINGS: The parent trial evaluated monthly SMC plus either azithromycin (AZ) or placebo, administered as directly observed therapy 4 times per year between August and November (2014-2016). In July 2014, 19,578 children aged 3-59 months were randomised by household to study group. Children who remained within the age range 3-59 months in August each year, plus children born into study households or who moved into the study area, received study drugs in 2015 and 2016. These analyses focus on the approximately 10,000 children (5,000 per country) under observation each year in the SMC plus placebo group. Despite high coverage and high adherence to SMC, the incidence of hospitalisations or deaths due to malaria and uncomplicated clinical malaria remained high in the study areas (overall incidence rates 12.5 [95% confidence interval (CI): 11.2, 14.1] and 871.1 [95% CI: 852.3, 890.6] cases per 1,000 person-years, respectively) and peaked in July each year, before SMC delivery began in August. The incidence rate ratio comparing SMC within the past 28 days with SMC more than 35 days ago-adjusted for age, country, and household clustering-was 0.13 (95% CI: 0.08, 0.20), P < 0.001 for malaria hospitalisations and deaths from malaria and 0.21 (95% CI 0.20, 0.23), P < 0.001 for uncomplicated malaria, indicating protective efficacy of 87.4% (95% CI: 79.6%, 92.2%) and 78.3% (95% CI: 76.8%, 79.6%), respectively. The prevalence of malaria parasitaemia at weekly surveys during the rainy season and at the end of the transmission season was several times higher in children who missed the SMC course preceding the survey contact, and the smallest prevalence ratio observed was 2.98 (95% CI: 1.95, 4.54), P < 0.001. The frequency of molecular markers of sulfadoxine-pyrimethamine (SP) and amodiaquine (AQ) resistance did not increase markedly over the study period either amongst study children or amongst school-age children resident in the study areas. After 3 years of SMC deployment, the day 28 PCR-unadjusted adequate clinical and parasitological response rate of the SP + AQ regimen in children with asymptomatic malaria was 98.3% (95% CI: 88.6%, 99.8%) in Burkina Faso and 96.1% (95% CI: 91.5%, 98.2%) in Mali. Key limitations of this study are the potential overdiagnosis of uncomplicated malaria by rapid diagnostic tests and the potential for residual confounding from factors related to adherence to the monthly SMC schedule. CONCLUSION: Despite strong evidence that SMC is providing a high level of protection, the burden of malaria remains substantial in the 2 study areas. These results emphasise the need for continuing support of SMC programmes. A fifth monthly SMC course is needed to adequately cover the whole transmission season in the study areas and in settings with similar epidemiology. TRIAL REGISTRATION: The AZ-SMC trial in which these data were collected was registered at clinicaltrials.gov: NCT02211729.
Assuntos
Antimaláricos/administração & dosagem , Características da Família , Malária/epidemiologia , Malária/prevenção & controle , Estações do Ano , Burkina Faso/epidemiologia , Quimioprevenção/métodos , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Seguimentos , Humanos , Lactente , Malária/sangue , Masculino , Mali/epidemiologiaRESUMO
Mass drug administration (MDA) with azithromycin (AZ) has been used successfully to control trachoma. However, several studies have shown that MDA with AZ has led to the emergence of resistance to AZ in Streptococcus pneumoniae. The emergence of resistance to AZ has also been observed when this antibiotic was combined with the antimalarials used for seasonal malaria chemoprevention (SMC). The development of antibiotic resistance, including resistance to AZ, is sometimes associated with the emergence of a bacterial clone that belongs to a specific serotype. We hypothesize that the increase in resistance of S. pneumoniae observed after 3 years of SMC with AZ might be associated with a change in the distribution of pneumococcal serotypes. Therefore, 698 randomly selected isolates from among the 1,468 isolates of S. pneumoniae obtained during carriage studies undertaken during an SMC plus AZ trial were serotyped. A polymerase chain reaction (PCR) multiplex assay using an algorithm adapted to the detection of the pneumococcal serotypes most prevalent in African countries was used for initial serotyping, and the Quellung technique was used to complement the PCR technique when necessary. Fifty-six serotypes were detected among the 698 isolates of S. pneumoniae. A swift appearance and disappearance of many serotypes was observed, but some serotypes including 6A, 19F, 19A, 23F, and 35B were persistent. The distribution of serotypes between isolates obtained from children who had received AZ or placebo was similar. An increase in AZ resistance was seen in several serotypes following exposure to AZ. Mass drug administration with AZ led to the emergence of resistance in pneumococci of several different serotypes and did not appear to be linked to the emergence of a single serotype.
Assuntos
Antibacterianos/uso terapêutico , Antimaláricos/uso terapêutico , Azitromicina/uso terapêutico , Portador Sadio/microbiologia , Farmacorresistência Bacteriana , Malária/prevenção & controle , Administração Massiva de Medicamentos , Nasofaringe/microbiologia , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/isolamento & purificação , Amodiaquina/uso terapêutico , Burkina Faso , Quimioprevenção/métodos , Pré-Escolar , Combinação de Medicamentos , Quimioterapia Combinada , Feminino , Humanos , Lactente , Masculino , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/uso terapêutico , Pirimetamina/uso terapêutico , Estações do Ano , Sorogrupo , Streptococcus pneumoniae/imunologia , Streptococcus pneumoniae/fisiologia , Sulfadoxina/uso terapêuticoRESUMO
BACKGROUND: Malaria in pregnancy affects both the mother and the fetus. However, evidence supporting treatment guidelines for uncomplicated (including asymptomatic) falciparum malaria in pregnant women is scarce and assessed in varied ways. We did a systematic literature review and individual patient data (IPD) meta-analysis to compare the efficacy and tolerability of different artemisinin-based or quinine-based treatments for malaria in pregnant women. METHODS: We did a systematic review of interventional or observational cohort studies assessing the efficacy of artemisinin-based or quinine-based treatments in pregnancy. Seven databases (MEDLINE, Embase, Global Health, Cochrane Library, Scopus, Web of Science, and Literatura Latino Americana em Ciencias da Saude) and two clinical trial registries (International Clinical Trials Registry Platform and ClinicalTrials.gov) were searched. The final search was done on April 26, 2019. Studies that assessed PCR-corrected treatment efficacy in pregnancy with follow-up of 28 days or more were included. Investigators of identified studies were invited to share data from individual patients. The outcomes assessed included PCR-corrected efficacy, PCR-uncorrected efficacy, parasite clearance, fever clearance, gametocyte development, and acute adverse events. One-stage IPD meta-analysis using Cox and logistic regression with random-effects was done to estimate the risk factors associated with PCR-corrected treatment failure, using artemether-lumefantrine as the reference. This study is registered with PROSPERO, CRD42018104013. FINDINGS: Of the 30 studies assessed, 19 were included, representing 92% of patients in the literature (4968 of 5360 episodes). Risk of PCR-corrected treatment failure was higher for the quinine monotherapy (n=244, adjusted hazard ratio [aHR] 6·11, 95% CI 2·57-14·54, p<0·0001) but lower for artesunate-amodiaquine (n=840, 0·27, 95% 0·14-0·52, p<0·0001), artesunate-mefloquine (n=1028, 0·56, 95% 0·34-0·94, p=0·03), and dihydroartemisinin-piperaquine (n=872, 0·35, 95% CI 0·18-0·68, p=0·002) than artemether-lumefantrine (n=1278) after adjustment for baseline asexual parasitaemia and parity. The risk of gametocyte carriage on day 7 was higher after quinine-based therapy than artemisinin-based treatment (adjusted odds ratio [OR] 7·38, 95% CI 2·29-23·82). INTERPRETATION: Efficacy and tolerability of artemisinin-based combination therapies (ACTs) in pregnant women are better than quinine. The lower efficacy of artemether-lumefantrine compared with other ACTs might require dose optimisation. FUNDING: The Bill & Melinda Gates Foundation, ExxonMobil Foundation, and the University of Oxford Clarendon Fund.
Assuntos
Antimaláricos/uso terapêutico , Malária Falciparum/tratamento farmacológico , Complicações Parasitárias na Gravidez/tratamento farmacológico , Quinina/uso terapêutico , Amodiaquina/uso terapêutico , Antibacterianos/uso terapêutico , Antimaláricos/efeitos adversos , Artemisininas/uso terapêutico , Artesunato/uso terapêutico , Atovaquona/uso terapêutico , Clindamicina/uso terapêutico , Combinação de Medicamentos , Quimioterapia Combinada , Feminino , Humanos , Mefloquina/uso terapêutico , Gravidez , Proguanil/uso terapêutico , Pirimetamina/uso terapêutico , Quinina/efeitos adversos , Quinolinas/uso terapêutico , Sulfadoxina/uso terapêuticoRESUMO
BACKGROUND: Malaria in pregnancy, including asymptomatic infection, has a detrimental impact on foetal development. Individual patient data (IPD) meta-analysis was conducted to compare the association between antimalarial treatments and adverse pregnancy outcomes, including placental malaria, accompanied with the gestational age at diagnosis of uncomplicated falciparum malaria infection. METHODS: A systematic review and one-stage IPD meta-analysis of studies assessing the efficacy of artemisinin-based and quinine-based treatments for patent microscopic uncomplicated falciparum malaria infection (hereinafter uncomplicated falciparum malaria) in pregnancy was conducted. The risks of stillbirth (pregnancy loss at ≥ 28.0 weeks of gestation), moderate to late preterm birth (PTB, live birth between 32.0 and < 37.0 weeks), small for gestational age (SGA, birthweight of < 10th percentile), and placental malaria (defined as deposition of malaria pigment in the placenta with or without parasites) after different treatments of uncomplicated falciparum malaria were assessed by mixed-effects logistic regression, using artemether-lumefantrine, the most used antimalarial, as the reference standard. Registration PROSPERO: CRD42018104013. RESULTS: Of the 22 eligible studies (n = 5015), IPD from16 studies were shared, representing 95.0% (n = 4765) of the women enrolled in literature. Malaria treatment in this pooled analysis mostly occurred in the second (68.4%, 3064/4501) or third trimester (31.6%, 1421/4501), with gestational age confirmed by ultrasound in 91.5% (4120/4503). Quinine (n = 184) and five commonly used artemisinin-based combination therapies (ACTs) were included: artemether-lumefantrine (n = 1087), artesunate-amodiaquine (n = 775), artesunate-mefloquine (n = 965), and dihydroartemisinin-piperaquine (n = 837). The overall pooled proportion of stillbirth was 1.1% (84/4361), PTB 10.0% (619/4131), SGA 32.3% (1007/3707), and placental malaria 80.1% (2543/3035), and there were no significant differences of considered outcomes by ACT. Higher parasitaemia before treatment was associated with a higher risk of SGA (adjusted odds ratio [aOR] 1.14 per 10-fold increase, 95% confidence interval [CI] 1.03 to 1.26, p = 0.009) and deposition of malaria pigment in the placenta (aOR 1.67 per 10-fold increase, 95% CI 1.42 to 1.96, p < 0.001). CONCLUSIONS: The risks of stillbirth, PTB, SGA, and placental malaria were not different between the commonly used ACTs. The risk of SGA was high among pregnant women infected with falciparum malaria despite treatment with highly effective drugs. Reduction of malaria-associated adverse birth outcomes requires effective prevention in pregnant women.
Assuntos
Antimaláricos/efeitos adversos , Artemisininas/efeitos adversos , Malária Falciparum/induzido quimicamente , Placenta/efeitos dos fármacos , Quinina/efeitos adversos , Adulto , Antimaláricos/farmacologia , Artemisininas/farmacologia , Feminino , Humanos , Malária Falciparum/complicações , Placenta/patologia , Gravidez , Resultado da Gravidez/epidemiologia , Quinina/farmacologia , Quinina/provisão & distribuição , Adulto JovemRESUMO
This study evaluated intermittent screening and treatment during pregnancy (ISTp) for malaria using rapid diagnostic tests (RDTs) at antenatal care (ANC) compared with passive case detection within the routine health system. The mixed-method evaluation included two cross-sectional household surveys (pre- and post-implementation of ISTp), in-depth interviews with health workers, and focus group discussions (FGDs) with pregnant women. Differences in proportions between surveys for a number of outcomes were tested; 553 and 534 current and recently pregnant women were surveyed (pre- and post-implementation, respectively). In-depth interviews were conducted with 29 health providers, and 13 FGDs were held with pregnant women. The proportion of pregnant women who received an RDT for malaria at ANC at least once during their pregnancy increased from pre- to post-implementation (19.2%; 95% CI: 14.9, 24.3 versus 42.5%; 95% CI: 36.6, 48.7; P < 0.0001), and the proportion of women who had more than one RDT also increased (16.5%; 95% CI: 13.1, 20.5 versus 27.7%; 95% CI: 23.0, 33.0; P = 0.0008). Post-implementation, however, only 8% of women who had completed their pregnancy received an RDT on three visits to ANC. Health workers were positive about ISTp mainly because of their perception that many pregnant women with malaria were asymptomatic. Health workers perceived pregnant women to have reservations about ISTp because of their dislike of frequent blood withdrawal, but pregnant women themselves were more positive. Intermittent screening and treatment during pregnancy was not sufficiently adopted by health workers to ensure the increased detection of malaria infections achievable with this strategy in this setting.
Assuntos
Malária/epidemiologia , Malária/prevenção & controle , Complicações Parasitárias na Gravidez/prevenção & controle , Adolescente , Adulto , Antimaláricos/uso terapêutico , Feminino , Humanos , Índia/epidemiologia , Gravidez , Complicações Parasitárias na Gravidez/epidemiologia , Complicações Parasitárias na Gravidez/parasitologia , População Rural , Adulto JovemRESUMO
OBJECTIVES: Mass administration of azithromycin has reduced mortality in children in sub-Saharan Africa but its mode of action is not well characterised. A recent trial found that azithromycin given alongside seasonal malaria chemoprevention was not associated with a reduction in mortality or hospital admissions in young children. We investigated the effect of azithromycin on the nutritional status of children enrolled in this study. METHODS: A total of 19 578 children in Burkina Faso and Mali were randomised to receive either azithromycin or placebo alongside seasonal malaria chemoprevention with sulfadoxine-pyrimethamine plus amodiaquine monthly for three malaria transmission seasons (2014-2016). After each transmission season, anthropometric measurements were collected from approximately 4000 randomly selected children (2000 per country) at a cross-sectional survey and used to derive nutritional status indicators. Binary and continuous outcomes between treatment arms were compared by Poisson and linear regression. RESULTS: Nutritional status among children was poor in both countries with evidence of acute and chronic malnutrition (24.9-33.3% stunted, 15.8-32.0% underweight, 7.2-26.4% wasted). There was a suggestion of improvement in nutritional status in Burkina Faso and deterioration in Mali over the study period. At the end of each malaria transmission season, nutritional status of children did not differ between treatment arms (seasonal malaria chemoprevention plus azithromycin or placebo) in either the intention-to-treat or per-protocol analyses (only children with at least three cycles of SMC in the current intervention year). CONCLUSIONS: The addition of azithromycin to seasonal malaria chemoprevention did not result in an improvement of nutritional outcomes in children in Burkina Faso and Mali.
OBJECTIFS: L'administration massive d'azithromycine a réduit la mortalité infantile en Afrique subsaharienne mais son mode d'action n'est pas bien caractérisé. Un essai récent a révélé que l'azithromycine administrée parallèlement à la chimioprévention du paludisme saisonnier n'était pas associée à une réduction de la mortalité ou des hospitalisations chez les jeunes enfants. Nous avons étudié l'effet de l'azithromycine sur l'état nutritionnel des enfants inscrits à cette étude. MÉTHODES: 19.578 enfants au Burkina Faso et au Mali ont été randomisés pour recevoir soit de l'azithromycine soit un placebo parallèlement à une chimioprévention du paludisme saisonnier avec du sulfadoxine-pyriméthamine plus de l'amodiaquine par mois pendant trois saisons de transmission du paludisme (2014-2016). Après chaque saison de transmission, des mesures anthropométriques ont été recueillies auprès d'environ 4.000 enfants sélectionnés au hasard (2.000 par pays) lors d'une enquête transversale et utilisées pour dériver des indicateurs de l'état nutritionnel. Les résultats binaires et continus entre les bras de traitement ont été comparés par la régression linéaire et de Poisson. RÉSULTATS: L'état nutritionnel des enfants était médiocre dans les deux pays avec des signes de malnutrition aiguë et chronique (24,9 à 33,3% de retard de croissance, 15,8 à 32,0% d'insuffisance pondérale, 7,2 à 26,4% d'émaciation). Il a été suggéré une amélioration de l'état nutritionnel au Burkina Faso et une détérioration au Mali au cours de la période d'étude. A la fin de chaque saison de transmission du paludisme, l'état nutritionnel des enfants ne différait pas entre les bras de traitement (chimioprévention contre le paludisme saisonnier plus azithromycine ou placebo) dans les analyses en intention de traiter ou selon le protocole (seulement les enfants avec au moins trois cycles de chimioprévention dans l'année d'intervention en cours). CONCLUSIONS: L'ajout d'azithromycine à la chimioprévention du paludisme saisonnier n'a pas entraîné d'amélioration des résultats nutritionnels chez les enfants au Burkina Faso et au Mali.
Assuntos
Antimaláricos/uso terapêutico , Azitromicina/uso terapêutico , Transtornos da Nutrição Infantil/epidemiologia , Malária/prevenção & controle , Antimaláricos/administração & dosagem , Azitromicina/administração & dosagem , Burkina Faso , Quimioprevenção , Pré-Escolar , Estudos Transversais , Quimioterapia Combinada , Feminino , Humanos , Lactente , Masculino , Mali , Administração Massiva de Medicamentos , Estado Nutricional , Estações do AnoRESUMO
OBJECTIVE: A trial was conducted in Burkina Faso and Mali to investigate whether addition of azithromycin to the antimalarials used for seasonal malaria chemoprevention reduces mortality and hospital admissions of children. We tested the sensitivity of nasal isolates of Streptococcus pneumoniae obtained during this trial to azithromycin and other antibiotics. METHODS: Azithromycin or placebo was administered monthly, in combination with the antimalarials used for seasonal malaria chemoprevention, for four months, over the annual malaria transmission seasons of 2014, 2015, and 2016. Nasopharyngeal swabs were collected from 2773 Burkinabe and 2709 Malian children on seven occasions: in July and December each year prior to and after drug administration, and at a final survey in early 2018. Pneumococci were isolated from nasopharyngeal swabs and tested for sensitivity to azithromycin and other antibiotics. RESULTS: A total of 5482 samples were collected. In Burkina Faso, the percentage of pneumococcal isolates resistant to azithromycin among children who had received it increased from 4.9% (95% CI: 2.4%, 9.9%) before the intervention to 25.6% (95% CI: 17.6%, 35.7%) afterward. In Mali, the increase was from 7.6% (95% CI: 3.8%, 14.4%) to 68.5% (95% CI: 55.1%, 79.4%). The percentage of resistant isolates remained elevated (17.7% (95% CI: 11.1%, 27.1%) in Burkina Faso and 19.1% (95% CI: 13.5%, 26.3%) in Mali) among children who had received azithromycin 1 year after stopping the intervention. An increase in resistance to azithromycin was also observed in children who had received a placebo but it was less marked. CONCLUSION: Addition of azithromycin to the antimalarial combination used for seasonal malaria chemoprevention was associated with an increase in resistance of pneumococci to azithromycin and erythromycin, which persisted 1 year after the last administration of azithromycin.
OBJECTIF: Un essai a été mené au Burkina Faso et au Mali pour investiguer si l'addition d'azithromycine aux antipaludéens utilisés dans le cadre de la chimioprévention du paludisme saisonnier réduisait la mortalité et les hospitalisations d'enfants. Nous avons testé la sensibilité à l'azithromycine et à d'autres antibiotiques pour les isolats nasaux de Streptococcus pneumoniae obtenus lors de cet essai. MÉTHODES: L'azithromycine ou un placebo a été administré mensuellement, en association avec les antipaludéens utilisés pour la chimioprévention du paludisme saisonnier, pendant 4 mois, durant les saisons de transmission annuelle du paludisme de 2014, 2015 et 2016. Des échantillons nasopharyngés ont été prélevés sur écouvillons chez 2.773 enfants burkinabés et 2.709 enfants maliens lors de 7 occasions: en juillet et en décembre chaque année avant et après l'administration du médicament, ainsi que lors d'une surveillance finale au début de 2018. Les pneumocoques ont été isolés à partir d'écouvillons nasopharyngés et soumis à des tests de sensibilité à l'azithromycine et à d'autres antibiotiques. RÉSULTATS: 5.482 échantillons ont été collectés. Au Burkina Faso, le pourcentage d'isolats de pneumocoque résistants à l'azithromycine chez les enfants qui l'avaient reçu était passé de 4,9% (IC95%: 2,4%, 9,9%) avant l'intervention à 25,6% (IC95%: 17,6-35,7%) après. Au Mali, l'augmentation est passée de 7,6% (IC95%: 3,8-14,4%) à 68,5% (IC95%: 55,1-79,4%). Le pourcentage d'isolats résistants est resté élevé (17,7% (IC95%: 11,1-27,1%) au Burkina Faso et 19,1% (IC95%: 13,5-26,3%) au Mali) chez les enfants ayant reçu l'azithromycine un an après arrêter l'intervention. Une augmentation de la résistance à l'azithromycine a également été observée chez les enfants ayant reçu un placebo, mais elle était moins marquée. CONCLUSION: L'ajout d'azithromycine à la combinaison antipaludique utilisée pour la chimioprévention du paludisme saisonnier était associé à une augmentation de la résistance du pneumocoque à l'azithromycine et à l'érythromycine, qui persistait un an après la dernière administration d'azithromycine.
Assuntos
Antimaláricos/farmacologia , Azitromicina/farmacologia , Malária/epidemiologia , Streptococcus pneumoniae/efeitos dos fármacos , Burkina Faso/epidemiologia , Quimioprevenção , Serviços de Saúde da Criança , Pré-Escolar , Farmacorresistência Bacteriana , Feminino , Humanos , Lactente , Malária/prevenção & controle , Masculino , Mali/epidemiologia , Estações do Ano , Streptococcus pneumoniae/isolamento & purificaçãoRESUMO
BACKGROUND: The control of malaria in pregnancy (MiP) in India relies on testing women who present with symptoms or signs suggestive of malaria. We hypothesised that intermittent screening and treatment for malaria at each antenatal care visit (ISTp) would improve on this approach and reduce the adverse effects of MiP. METHODS: A cluster randomised controlled trial comparing ISTp versus passive case detection (PCD) was conducted in Jharkhand state. Pregnant women of all parities with a gestational age of 18-28 weeks were enrolled. Women in the ISTp group were screened with a rapid diagnostic test (RDT) for malaria at each antenatal clinic visit and those in the PCD group were screened only if they had symptoms or signs suggestive of malaria. All RDT positive women were treated with artesunate/sulfadoxine-pyrimethamine. The primary endpoint was placental malaria, determined by placental histology, and the key secondary endpoints were birth weight, gestational age, vital status of the newborn baby and maternal anaemia. RESULTS: Between April 2012 and September 2015, 6868 women were enrolled; 3300 in 46 ISTp clusters and 3568 in 41 PCD clusters. In the ISTp arm, 4.9% of women were tested malaria positive and 0.6% in the PCD arm. There was no difference in the prevalence of placental malaria in the ISTp (87/1454, 6.0%) and PCD (65/1560, 4.2%) groups (6.0% vs 4.2%; OR 1.34, 95% CI 0.78 to 2.29, p=0.29) or in any of the secondary endpoints. CONCLUSION: ISTp detected more infections than PCD, but monthly ISTp with the current generation of RDT is unlikely to reduce placental malaria or impact on pregnancy outcomes. ISTp trials with more sensitive point-of-care diagnostic tests are needed.
RESUMO
BACKGROUND: Mass administration of azithromycin for trachoma control led to a sustained reduction in all-cause mortality among Ethiopian children. Whether the addition of azithromycin to the monthly sulfadoxine-pyrimethamine plus amodiaquine used for seasonal malaria chemoprevention could reduce mortality and morbidity among African children was unclear. METHODS: We randomly assigned children 3 to 59 months of age, according to household, to receive either azithromycin or placebo, together with sulfadoxine-pyrimethamine plus amodiaquine, during the annual malaria-transmission season in Burkina Faso and Mali. The drug combinations were administered in four 3-day cycles, at monthly intervals, for three successive seasons. The primary end point was death or hospital admission for at least 24 hours that was not due to trauma or elective surgery. Data were recorded by means of active and passive surveillance. RESULTS: In July 2014, a total of 19,578 children were randomly assigned to receive seasonal malaria chemoprevention plus either azithromycin (9735 children) or placebo (9843 children); each year, children who reached 5 years of age exited the trial and new children were enrolled. In the intention-to-treat analysis, the overall number of deaths and hospital admissions during three malaria-transmission seasons was 250 in the azithromycin group and 238 in the placebo group (events per 1000 child-years at risk, 24.8 vs. 23.5; incidence rate ratio, 1.1; 95% confidence interval [CI], 0.88 to 1.3). Results were similar in the per-protocol analysis. The following events occurred less frequently with azithromycin than with placebo: gastrointestinal infections (1647 vs. 1985 episodes; incidence rate ratio, 0.85; 95% CI, 0.79 to 0.91), upper respiratory tract infections (4893 vs. 5763 episodes; incidence rate ratio, 0.85; 95% CI, 0.81 to 0.90), and nonmalarial febrile illnesses (1122 vs. 1424 episodes; incidence rate ratio, 0.79; 95% CI, 0.73 to 0.87). The prevalence of malaria parasitemia and incidence of adverse events were similar in the two groups. CONCLUSIONS: Among children in Burkina Faso and Mali, the addition of azithromycin to the antimalarial agents used for seasonal malaria chemoprevention did not result in a lower incidence of death or hospital admission that was not due to trauma or surgery than antimalarial agents plus placebo, although a lower disease burden was noted with azithromycin than with placebo. (Funded by the Joint Global Health Trials scheme; ClinicalTrials.gov number, NCT02211729.).
Assuntos
Antibacterianos/uso terapêutico , Antimaláricos/uso terapêutico , Azitromicina/uso terapêutico , Mortalidade da Criança , Hospitalização/estatística & dados numéricos , Malária/prevenção & controle , Amodiaquina/uso terapêutico , Burkina Faso/epidemiologia , Pré-Escolar , Esquema de Medicação , Combinação de Medicamentos , Quimioterapia Combinada , Feminino , Humanos , Incidência , Lactente , Mortalidade Infantil , Malária/mortalidade , Masculino , Mali/epidemiologia , Administração Massiva de Medicamentos , Parasitemia/tratamento farmacológico , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêuticoRESUMO
BACKGROUND: In India, the recommended first-line treatment for malaria in the second and third trimester of pregnancy is artesunate + sulfadoxine-pyrimethamine (AS+SP). However, data on safety and efficacy of artemisinin-based combination therapy (ACT) in pregnancy is limited. This study assessed the safety and efficacy of AS+SP and artesunate + mefloquine (AS+MQ) for treatment of Plasmodium falciparum in pregnancy in India. METHODS: This open-label, randomized clinical trial was conducted from October 2010 to December 2013 at three sites in India (Ranchi and Jamshedpur in Jharkhand state, and Rourkela in Odisha state). Pregnant women in the second or third trimester who had P. falciparum mono-infection of any parasite density with or without fever were randomized to receive AS+SP or AS+MQ. Blood slides and filter paper samples for Polymerase Chain Reaction (PCR) were collected on days 0, 1, 2, 3, 14, 21, 28, 42 and 63 post treatment. Women were followed up at delivery and at day 42 postpartum. FINDINGS: Two hundred and forty-eight women of 7064 pregnant women (3.5%) who were screened at monthly antenatal clinics had a P. falciparum mono-infection and were randomized to receive AS+SP (125) or AS+MQ (123) and all of these women were included in the intention to treat (ITT) analysis. The primary endpoint of an adequate clinical and parasite response (ACPR) on day 63 was not available for 9 women who were counted as treatment failure in the ITT analysis. In the ITT population, the ACPR was 121/125 (96.8%; 95% Confidence interval (CI) 92.0-99.1%) in the AS+SP group and 117/123 (95.1%; 95% CI 89.7-98.2) in the AS+MQ group. Among the 239 women (121 from the AS+SP arm and 118 from the AS+MQ arm) who completed the day 63 follow up (per protocol analysis) the ACPR was 100% in the AS+SP group and 99.2% (117/118) in the AS+MQ group. There were five serious adverse events (SAE) among pregnant women (4 in the AS+SP group and 1 in the AS+MQ group) and 13 fetal/neonatal SAEs (7 in the AS+SP group and 6 in the AS+MQ) but none of them were related to the study drugs. A higher proportion of women in the AS+MQ arm reported vomiting within 7 days post-treatment than did women in the AS+SP arm (6.9 vs. 1.6%; p = 0.001). CONCLUSION: Both AS+SP and AS+MQ are safe and effective for treatment of uncomplicated falciparum malaria in pregnancy in India. Trial registration CTRI This study is registered with Clinical Trial Registry India (CTRI), number CTRI/2009/091/001055. Date of Registration 11 January 2010, http://ctri.nic.in/Clinicaltrials/pmaindet2.php?trialid=1185&EncHid=&userName=anvikar.
Assuntos
Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Artesunato/uso terapêutico , Malária Falciparum/prevenção & controle , Mefloquina/uso terapêutico , Complicações Parasitárias na Gravidez/prevenção & controle , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Adulto , Combinação de Medicamentos , Feminino , Humanos , Incidência , Índia/epidemiologia , Análise de Intenção de Tratamento , Malária Falciparum/epidemiologia , Plasmodium falciparum/efeitos dos fármacos , Gravidez , Complicações Parasitárias na Gravidez/epidemiologia , Prevalência , Resultado do Tratamento , Adulto JovemRESUMO
In many parts of the African Sahel and sub-Sahel, where malaria remains a major cause of mortality and morbidity, transmission of the infection is highly seasonal. Seasonal malaria chemoprevention (SMC), which involves administration of a full course of malaria treatment to young children at monthly intervals during the high transmission season, is proving to be an effective malaria control measure in these areas. However, SMC does not provide complete protection and it is demanding to deliver for both families and healthcare givers. Furthermore, there is a risk of the emergence in the future of resistance to the drugs, sulfadoxine-pyrimethamine and amodiaquine, that are currently being used for SMC. Substantial progress has been made in the development of malaria vaccines during the past decade and one malaria vaccine, RTS,S/AS01, has received a positive opinion from the European Medicines Authority and will soon be deployed in large-scale, pilot implementation projects in sub-Saharan Africa. A characteristic feature of this vaccine, and potentially of some of the other malaria vaccines under development, is that they provide a high level of efficacy during the period immediately after vaccination, but that this wanes rapidly, perhaps because it is difficult to develop effective immunological memory to malaria antigens in subjects exposed previously to malaria infection. A potentially effective way of using malaria vaccines with high initial efficacy but which provide only a short period of protection could be annual, mass vaccination campaigns shortly before each malaria transmission season in areas where malaria transmission is confined largely to a few months of the year.
Assuntos
Vacinas Antimaláricas/administração & dosagem , Vacinas Antimaláricas/imunologia , Malária/prevenção & controle , Estações do Ano , Vacinação/estatística & dados numéricos , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia , África SubsaarianaRESUMO
BACKGROUND: Use of artemisinin-based combination therapy (ACT), such as artemether-lumefantrine (AL), requires a strict dosing schedule that follows the drugs' pharmacokinetic properties. The quality of malaria case management was assessed in two areas in rural Tanzania, to ascertain patient characteristics and facility-specific factors that influence correct dosing of AL for management of uncomplicated malaria. METHODS: Exit interviews were conducted with patients attending health facilities for initial illness consultation. Information about health workers' training and supervision visits was collected. Health facilities were inventoried for capacity and availability of medical products related to care of malaria patients. The outcome was correct dosing of AL based on age and weight. Logistic regression was used to assess health facility factors and patient characteristics associated with correct dosing of AL by age and weight. RESULTS: A total of 1,531 patients were interviewed, but 60 pregnant women were excluded from the analysis. Only 503 (34.2%) patients who received AL were assessed for correct dosing. Most patients who received AL (85.3%) were seen in public health facilities, 75.7% in a dispensary and 91.1% in a facility that had AL in stock on the survey day. Overall, 92.1% (463) of AL prescriptions were correct by age or weight; but 85.7% of patients received correct dosing by weight alone and 78.5% received correct dosing by age alone. In multivariate analysis, patients in the middle dosing bands in terms of age or weight, had statistically significant lower odds of correct AL dosing (p < 0.05) compared to those in the lowest age or weight group. Other factors such as health worker supervision and training on ACT did not improve the odds of correct AL dosing. CONCLUSION: Although malaria treatment guidelines indicate AL dosing can be prescribed based on age or weight of the patient, findings from this study show that patients within the middle age and weight dosing bands were least likely to receive a correct dose by either measure. Clinicians should be made aware of AL dosing errors for patients aged three to 12 years and advised to use weight-based prescriptions whenever possible.
Assuntos
Antimaláricos/administração & dosagem , Artemisininas/administração & dosagem , Etanolaminas/administração & dosagem , Fluorenos/administração & dosagem , Malária/tratamento farmacológico , Adolescente , Combinação Arteméter e Lumefantrina , Criança , Pré-Escolar , Combinação de Medicamentos , Feminino , Humanos , Modelos Logísticos , Malária/epidemiologia , Masculino , Análise Multivariada , Tanzânia/epidemiologia , Resultado do TratamentoRESUMO
BACKGROUND: Artemisinin-based combination treatment (ACT) has been widely adopted as one of the main malaria control strategies. However, its promise to save thousands of lives in sub-Saharan Africa depends on how effective the use of ACT is within the routine health system. The INESS platform evaluated effective coverage of ACT in several African countries. Timely access within 24 hours to an authorized ACT outlet is one of the determinants of effective coverage and was assessed for artemether-lumefantrine (Alu), in two district health systems in rural Tanzania. METHODS: From October 2009 to June 2011 we conducted continuous rolling household surveys in the Kilombero-Ulanga and the Rufiji Health and Demographic Surveillance Sites (HDSS). Surveys were linked to the routine HDSS update rounds. Members of randomly pre-selected households that had experienced a fever episode in the previous two weeks were eligible for a structured interview. Data on individual treatment seeking, access to treatment, timing, source of treatment and household costs per episode were collected. Data are presented on timely access from a total of 2,112 interviews in relation to demographics, seasonality, and socio economic status. RESULTS: In Kilombero-Ulanga, 41.8% (CI: 36.6-45.1) and in Rufiji 36.8% (33.7-40.1) of fever cases had access to an authorized ACT provider within 24 hours of fever onset. In neither of the HDSS site was age, sex, socio-economic status or seasonality of malaria found to be significantly correlated with timely access. CONCLUSION: Timely access to authorized ACT providers is below 50% despite interventions intended to improve access such as social marketing and accreditation of private dispensing outlets. To improve prompt diagnosis and treatment, access remains a major bottle neck and new more innovative interventions are needed to raise effective coverage of malaria treatment in Tanzania.