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1.
Infect Dis Poverty ; 9(1): 21, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32046780

RESUMO

BACKGROUND: Plasmodium falciparum malaria is endemic in the southern sahelian zone of Mauritania where intense internal and trans-border human and livestock movement occurs. The risk of importation and spread of drug-resistant parasites need to be regularly assessed in this region. The objective of the study was to assess the recent malaria situation near the Mauritania-Mali border. METHODS: Between February 2015 and December 2017, patients with fever or history of fever during the previous 48 h, presenting at the health centre of Kobeni city, were screened for malaria using a rapid diagnostic test (RDT) and microscopic examination of blood smears. The diagnosis was later confirmed by PCR. Cohen's kappa statistics was used to estimate the degree of agreement between diagnostic methods. Fisher's exact test was used to compare proportions. The odds ratio was calculated to measure the association between the use of bed nets and malaria infection. RESULTS: A total of 2326 febrile patients (mean age, 20.2 years) were screened for malaria. The presence of malaria parasites was detected by RDT and microscopy in 53.0% and 49.3% of febrile patients, respectively, and was confirmed by PCR in 59.7% (45 missing data). Of 1361 PCR-positive samples, 1205 (88.5%) were P. falciparum, 47 (3.5%) P. vivax, and 99 (7.3%) P. falciparum-P. vivax mixed infection. Malaria transmission occurred mostly during and shortly after the rainy season. The annual rainfall was relatively low in 2016 (267 mm) and 2017 (274 mm), compared to 2015 (448 mm), and coincided with a decline in malaria prevalence in 2016-2017. Although 71.8% of febrile patients reported to possess at least one bed net in the household in our questionnaire, its reported use was not protective against malaria infection (odds ratio: 1.1, 95% CI: 0.91-1.32). CONCLUSIONS: Our study confirmed that P. falciparum is the dominant species in the sahelian zone and that malaria transmission is seasonal and associated with rainfall in this zone. The application of the current national policy based on rapid and reliable malaria diagnosis, case management with artemisinin-based combination therapy, intermittent preventive treatment for pregnant women, distribution and use of long-lasting insecticide impregnated bed nets, and the planned introduction of seasonal malaria chemoprevention for all children under 6 years old is expected to sustainably reduce malaria transmission in this zone.


Assuntos
Antimaláricos/uso terapêutico , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Adolescente , Artemisininas/uso terapêutico , Criança , Pré-Escolar , Coinfecção/diagnóstico , Coinfecção/tratamento farmacológico , Coinfecção/epidemiologia , Testes Diagnósticos de Rotina/métodos , Quimioterapia Combinada , Feminino , Humanos , Malária Falciparum/diagnóstico , Malária Falciparum/tratamento farmacológico , Malária Vivax/diagnóstico , Malária Vivax/tratamento farmacológico , Masculino , Mauritânia/epidemiologia , Plasmodium falciparum/isolamento & purificação , Plasmodium vivax/isolamento & purificação , Estações do Ano
2.
BMC Med ; 18(1): 9, 2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31987052

RESUMO

BACKGROUND: In order to improve malaria burden estimates in low transmission settings, more sensitive tools and efficient sampling strategies are required. This study evaluated the use of serological measures from repeated health facility-based cross-sectional surveys to investigate Plasmodium falciparum and Plasmodium vivax transmission dynamics in an area nearing elimination in Indonesia. METHODS: Quarterly surveys were conducted in eight public health facilities in Kulon Progo District, Indonesia, from May 2017 to April 2018. Demographic data were collected from all clinic patients and their companions, with household coordinates collected using participatory mapping methods. In addition to standard microscopy tests, bead-based serological assays were performed on finger-prick bloodspot samples from 9453 people. Seroconversion rates (SCR, i.e. the proportion of people in the population who are expected to seroconvert per year) were estimated by fitting a simple reversible catalytic model to seroprevalence data. Mixed effects logistic regression was used to examine factors associated with malaria exposure, and spatial analysis was performed to identify areas with clustering of high antibody responses. RESULTS: Parasite prevalence by microscopy was extremely low (0.06% (95% confidence interval 0.03-0.14, n = 6) and 0 for P. vivax and P. falciparum, respectively). However, spatial analysis of P. vivax antibody responses identified high-risk areas that were subsequently the site of a P. vivax outbreak in August 2017 (62 cases detected through passive and reactive detection systems). These areas overlapped with P. falciparum high-risk areas and were detected in each survey. General low transmission was confirmed by the SCR estimated from a pool of the four surveys in people aged 15 years old and under (0.020 (95% confidence interval 0.017-0.024) and 0.005 (95% confidence interval 0.003-0.008) for P. vivax and P. falciparum, respectively). The SCR estimates in those over 15 years old were 0.066 (95% confidence interval 0.041-0.105) and 0.032 (95% confidence interval 0.015-0.069) for P. vivax and P. falciparum, respectively. CONCLUSIONS: These findings demonstrate the potential use of health facility-based serological surveillance to better identify and target areas still receptive to malaria in an elimination setting. Further implementation research is needed to enable integration of these methods with existing surveillance systems.


Assuntos
Surtos de Doenças , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Estudos Soroepidemiológicos , Adulto , Análise por Conglomerados , Estudos Transversais , Testes Diagnósticos de Rotina , Feminino , Instalações de Saúde , Humanos , Indonésia/epidemiologia , Modelos Logísticos , Malária/epidemiologia , Masculino , Microscopia , Pessoa de Meia-Idade , Plasmodium falciparum/imunologia , Plasmodium vivax/imunologia , Prevalência , Análise Espacial
3.
PLoS Med ; 16(12): e1002992, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31834890

RESUMO

BACKGROUND: To reduce the risk of drug-induced haemolysis, all patients should be tested for glucose-6-phosphate dehydrogenase (G6PD) deficiency (G6PDd) prior to prescribing primaquine (PQ)-based radical cure for the treatment of vivax malaria. This systematic review and individual patient meta-analysis assessed the utility of a qualitative lateral flow assay from Access Bio/CareStart (Somerset, NJ) (CareStart Screening test for G6PD deficiency) for the diagnosis of G6PDd compared to the gold standard spectrophotometry (International Prospective Register of Systematic Reviews [PROSPERO]: CRD42019110994). METHODS AND FINDINGS: Articles published on PubMed between 1 January 2011 and 27 September 2019 were screened. Articles reporting performance of the standard CSG from venous or capillary blood samples collected prospectively and considering spectrophotometry as gold standard (using kits from Trinity Biotech PLC, Wicklow, Ireland) were included. Authors of articles fulfilling the inclusion criteria were contacted to contribute anonymized individual data. Minimal data requested were sex of the participant, CSG result, spectrophotometry result in U/gHb, and haemoglobin (Hb) reading. The adjusted male median (AMM) was calculated per site and defined as 100% G6PD activity. G6PDd was defined as an enzyme activity of less than 30%. Pooled estimates for sensitivity and specificity, unconditional negative predictive value (NPV), positive likelihood ratio (LR+), and negative likelihood ratio (LR-) were calculated comparing CSG results to spectrophotometry using a random-effects bivariate model. Of 11 eligible published articles, individual data were available from 8 studies, 6 from Southeast Asia, 1 from Africa, and 1 from the Americas. A total of 5,815 individual participant data (IPD) were available, of which 5,777 results (99.3%) were considered for analysis, including data from 3,095 (53.6%) females. Overall, the CSG had a pooled sensitivity of 0.96 (95% CI 0.90-0.99) and a specificity of 0.95 (95% CI 0.92-0.96). When the prevalence of G6PDd was varied from 5% to 30%, the unconditional NPV was 0.99 (95% CI 0.94-1.00), with an LR+ and an LR- of 18.23 (95% CI 13.04-25.48) and 0.05 (95% CI 0.02-0.12), respectively. Performance was significantly better in males compared to females (p = 0.027) but did not differ significantly between samples collected from capillary or venous blood (p = 0.547). Limitations of the study include the lack of wide geographical representation of the included data and that the CSG results were generated under research conditions, and therefore may not reflect performance in routine settings. CONCLUSIONS: The CSG performed well at the 30% threshold. Its high NPV suggests that the test is suitable to guide PQ treatment, and the high LR+ and low LR- render the test suitable to confirm and exclude G6PDd. Further operational studies are needed to confirm the utility of the test in remote endemic settings.


Assuntos
Testes Diagnósticos de Rotina , Deficiência de Glucosefosfato Desidrogenase/diagnóstico , Glucosefosfato Desidrogenase/genética , Primaquina/uso terapêutico , Testes Diagnósticos de Rotina/métodos , Doenças Endêmicas , Feminino , Deficiência de Glucosefosfato Desidrogenase/tratamento farmacológico , Humanos , Malária/tratamento farmacológico , Malária/epidemiologia , Malária Vivax/epidemiologia , Masculino , Sistemas Automatizados de Assistência Junto ao Leito , Primaquina/efeitos adversos , Sensibilidade e Especificidade
4.
PLoS Negl Trop Dis ; 13(11): e0007876, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31710604

RESUMO

Despite efforts made over decades by the Peruvian government to eliminate malaria, Plasmodium vivax remains a challenge for public health decision-makers in the country. The uneven distribution of its incidence, plus its complex pattern of dispersion, has made ineffective control measures based on global information that lack the necessary detail to understand transmission fully. In this sense, population genetic tools can complement current surveillance. This study describes the genetic diversity and population structure from September 2012 to March 2015 in three geographically distant settlements, Cahuide (CAH), Lupuna (LUP) and Santa Emilia (STE), located in the Peruvian Amazon. A total 777 P. vivax mono-infections, out of 3264, were genotyped. Among study areas, LUP showed 19.7% of polyclonal infections, and its genetic diversity (Hexp) was 0.544. Temporal analysis showed a significant increment of polyclonal infections and Hexp, and the introduction and persistence of a new parasite population since March 2013. In STE, 40.1% of infections were polyclonal, with Hexp = 0.596. The presence of four genetic clusters without signals of clonal expansion and infections with lower parasite densities compared against the other two areas were also found. At least four parasite populations were present in CAH in 2012, where, after June 2014, malaria cases decreased from 213 to 61, concomitant with a decrease in polyclonal infections (from 0.286 to 0.18), and expectedly variable Hexp. Strong signals of gene flow were present in the study areas and wide geographic distribution of highly diverse parasite populations were found. This study suggests that movement of malaria parasites by human reservoirs connects geographically distant malaria transmission areas in the Peruvian Amazon. The maintenance of high levels of parasite genetic diversity through human mobility is a critical barrier to malaria elimination in this region.


Assuntos
Transmissão de Doença Infecciosa , Genótipo , Malária Vivax/epidemiologia , Malária Vivax/parasitologia , Plasmodium vivax/classificação , Plasmodium vivax/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Técnicas de Genotipagem , Humanos , Incidência , Lactente , Recém-Nascido , Estudos Longitudinais , Malária Vivax/transmissão , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Epidemiologia Molecular , Peru/epidemiologia , Plasmodium vivax/isolamento & purificação , Adulto Jovem
5.
BMC Infect Dis ; 19(1): 935, 2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694574

RESUMO

BACKGROUND: Malaria is the fifth leading cause of death worldwide. Pakistan is considered as a moderate malaria-endemic country but still, 177 million individuals are at risk of malaria. Roughly 60% of Pakistan's population, live in malaria-endemic regions. The present study is based upon the survey of various health care centers in 10 major cities of Northern and Southern Punjab to find out the malarial infection patterns in 2015. The diagnosis, seasonal variations, age and gender-wise distribution of Plasmodium spp. circulating in the study area were also included in the objectives. METHODS: The malaria-suspected patients '16075' were enrolled for malaria diagnosis using microscopy, out of which 925 were malaria positive which were processed for molecular analysis using nested PCR. The 18S rRNA genes of Plasmodium species were amplified, sequenced, blast and the phylogenetic tree was constructed based on sequences using online integrated tool MEGA7. RESULTS: The 364 cases recruited from Northern Punjab with the highest incidence in Rawalpindi (25.5%) and lowest in Chakwal (15.9%). From Southern Punjab 561 cases were enlisted Rajanpur (21.4%) maximum and lowest from Multan and Rahim Yar Khan (18%). The slide positivity rate, annual parasite incidence, and annual blood examination rates were 5.7 per 1000 population, 0.1, and 0.2% respectively. The only P. vivax (66.7%), P. falciparum (23.7%) and mixed infection by these two species (9.6%) were diagnosed. The same trend (P. vivax > P. falciparum > mixed infection) in species identification %age was confirmed from molecular analysis. However, the occurrence of malaria was higher in Southern Punjab (5.5%) as compared to the Northern Punjab (4.0%). The overall malaria percentage occurrence of treatment-seeking patients in all recruited cities of Punjab was 4.9%. The age-group of 1-20 and males among genders were more affected by malaria. The comparison of different seasons showed that the malaria infection was at a peak in Summer and post-monsoon. CONCLUSION: The incidence of malaria was high in the flood infected rural areas of Southern Punjab, Summer, and post-monsoon. The age group (1-20) and gender-wise males were more affected by malaria.


Assuntos
Coinfecção/epidemiologia , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Plasmodium vivax/isolamento & purificação , Estações do Ano , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Cidades/epidemiologia , Clima , Coinfecção/diagnóstico , Coinfecção/parasitologia , Estudos Transversais , Feminino , Humanos , Incidência , Lactente , Malária Falciparum/diagnóstico , Malária Falciparum/parasitologia , Malária Vivax/diagnóstico , Malária Vivax/parasitologia , Masculino , Microscopia , Pessoa de Meia-Idade , Paquistão/epidemiologia , Filogenia , Plasmodium/genética , Plasmodium vivax/genética , Reação em Cadeia da Polimerase , Prevalência , RNA Ribossômico 18S/genética , Inquéritos e Questionários , Adulto Jovem
6.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 31(5): 552-554, 2019 Sep 27.
Artigo em Chinês | MEDLINE | ID: mdl-31713394

RESUMO

OBJECTIVE: To analyze the evaluation results of malaria elimination and summarize the experience in Jiujiang City, so as to provide the evidence for formulating the surveillance work plan post-malaria elimination. METHODS: According to the requirements and arrangements of Jiangxi Eliminating Malaria Action Plan (2010 - 2020), the evaluation of malaria elimination was completed in all 13 counties (cites and districts) of Jiujiang City from 2013 to 2016, and the data were collected and analyzed. RESULTS: In Jiujiang City, the last local malaria case was reported in 2008. From 2010 to 2016, there were 20 imported malaria cases reported, including 12 cases of falciparum malaria, 7 cases of vivax malaria, and 1 case of mixed infection. Totally 67 501 fever patients were tested for Plasmodium and 13 cases were positive, with the positive rate of 0.02%. The comprehensive evaluation scores were between 88.75 and 98.15 in all the 13 counties (cities and districts), which meant they all reached the evaluative criteria. CONCLUSIONS: All 13 counties (cities and districts) of Jiujiang City have passed the city level evaluative criteria of malaria elimination, and the key work should be the prevention and surveillance of imported malaria in the future.


Assuntos
Erradicação de Doenças , Malária Falciparum , Malária Vivax , Malária , Plasmodium , China/epidemiologia , Cidades , Erradicação de Doenças/normas , Humanos , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Vigilância da População
7.
BMC Infect Dis ; 19(1): 922, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31666012

RESUMO

BACKGROUND: In southern Papua, Indonesia, malaria is highly prevalent in young children and is a significant cause of morbidity and early mortality. The association between malaria and delayed mortality is unknown. METHODS: Routinely-collected hospital surveillance data from southern Papua, Indonesia, were used to assess the risk of recurrent malaria and mortality within 12 months of an initial presentation with malaria in all children younger than 5 years old attending the local hospital. Analysis was primarily by Kaplan Meier and Cox regression methods. RESULTS: In total 15,716 children presenting with malaria between April 2004 and December 2013 were included in the analysis; 6184 (39.3%) with Plasmodium falciparum, 7499 (47.7%) with P. vivax, 203 (1.3%) with P. malariae, 3 with P. ovale and 1827 (11.6%) with mixed infections. Within 1 year, 48.4% (7620/15,716) of children represented a total of 16,957 times with malaria (range 1 to 11 episodes), with the incidence of malaria being greater in patients initially presenting with P. vivax infection (1334 [95%CI 1307-1361] per 1000 patient years) compared to those with P. falciparum infection (920 [896-944]). In total 266 (1.7%) children died within 1 year of their initial presentation, 129 (48.5%) within 30 days and 137 (51.5%) between 31 and 365 days. There was no significant difference in the mortality risk in patients infected with P. vivax versus P. falciparum either before 30 days (Hazard Ratio (HR) 1.02 [0.69,1.49]) or between 31 and 365 days (HR = 1.30 [0.90,1.88]). Children who died had a greater incidence of malaria, 2280 [95%CI 1946-2671] per 1000 patient years preceding their death, compared to 1141 [95%CI 1124-1158] per 1000 patient years in those surviving. CONCLUSIONS: Children under-5 years old with P. vivax malaria, are at significant risk of multiple representations with malaria and of dying within 1 year of their initial presentation. Preventing recurrent malaria must be a public health priority in this vulnerable population.


Assuntos
Malária/mortalidade , Pré-Escolar , Coinfecção/epidemiologia , Coinfecção/mortalidade , Feminino , Hospitais/estatística & dados numéricos , Humanos , Incidência , Indonésia/epidemiologia , Lactente , Malária/epidemiologia , Malária Falciparum/epidemiologia , Malária Falciparum/mortalidade , Malária Vivax/epidemiologia , Malária Vivax/mortalidade , Masculino , Morbidade , Prevalência
8.
BMC Res Notes ; 12(1): 645, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31585549

RESUMO

OBJECTIVE: We investigated this outbreak to describe the magnitude and associated risk factors due to the malaria outbreak in Tanquae Abergelle district, Tigray, Ethiopia, in 2017. RESULT: Case fatality rate of this study was zero. Among the 62 cases and 124 controls, the presence of mosquito breeding sites [OR = 6.56 CI (2.09-20.58) P value = 0.001], sleeping outside a home [OR = 5.06 CI (1.75-14.61) P-value = 0.003] and having unscreened window [OR = 14.89 CI (1.87-118.25) P-value = 0.011] were associated with illness in multivariate analysis.


Assuntos
Surtos de Doenças , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Mosquiteiros/estatística & dados numéricos , Adolescente , Adulto , Animais , Anopheles/parasitologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Etiópia/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Malária Falciparum/parasitologia , Malária Falciparum/transmissão , Malária Vivax/parasitologia , Malária Vivax/transmissão , Masculino , Pessoa de Meia-Idade , Mosquitos Vetores/parasitologia , Plasmodium falciparum/patogenicidade , Plasmodium vivax/patogenicidade , Fatores de Risco , Sono
9.
Rev Inst Med Trop Sao Paulo ; 61: e52, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31531630

RESUMO

In 2018, Bhutan reported 54 cases of malaria, of which six were indigenous, 14 introduced and 34 imported. Considering the continuous reduction in the number of indigenous cases, Bhutan plans to eliminate malaria by 2025 under the Bhutan Malaria Elimination Strategy. The study was conducted to assess the presence of asymptomatic plasmodial infection in both, Bhutanese population living in malaria-risk areas and in migrant workers to guide the elimination strategies. A cross-sectional study was conducted from April to May 2016 in 750 Bhutanese people and 473 migrant workers. Plasmodium falciparum and Plasmodium vivax infections were investigated by using a rapid diagnostic test (RDT) and the polymerase chain reaction (PCR). Prevalence of asymptomatic plasmodial infection based on PCR was 0.27% (95% CI: 0.05-1.07%) among Bhutanese people with a mean age of 43 years old. The proportions of males and females were 45% and 55%, respectively. Among migrant workers, the prevalence of asymptomatic plasmodial infection was 0.42% (95% CI: 0.07-1.69%) with a mean age of 30 years old. The majority of migrant workers were from the neighboring Indian State of West Bengal (57.51%), followed by Assam (12.26%). RDT in both study groups did not detect any plasmodial infection. The presence of a low prevalence of asymptomatic plasmodial infection indicates that the current elimination strategies and interventions are effective.


Assuntos
Malária Falciparum/diagnóstico , Malária Vivax/diagnóstico , Infecções Assintomáticas , Butão/epidemiologia , Estudos Transversais , Feminino , Humanos , Índia , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Malária Vivax/epidemiologia , Malária Vivax/prevenção & controle , Masculino , Reação em Cadeia da Polimerase , Prevalência , Migrantes
10.
Turkiye Parazitol Derg ; 43(3): 102-105, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31502770

RESUMO

Objective: We aimed to evaluate the epidemiological data of malaria cases by using the data of Gaziantep Public Health Directorate between January 2005 and December 2015. Methods: Blood samples were taken from suspicious cases and temporary agricultural workers living in the Firat Watershed and in areas in where malaria was seen before and in the tent cities of Islahiye, Nizip and Karkamis by request of the ministry. The cases were evaluated in terms of age, gender, detected malaria species, months when malaria was detected, and whether they were imported cases. Results: Thirty-one malaria cases were detected in blood samples taken from 184.305 patients. The malaria positivity rate was determined as 0.017%. Five of the patients (16.3%) were indigenous; 2 (6.5%) were cases with relapse and 24 cases (77.2%) were imported. Conclusion: In our study, we last saw a new indigenous case in 2005. In the following years , cases with relapses and cases originating from abroad were seen, which was linked to the ease of transportation and the increase in touristic and commercial relations. Although lack of malaria in the samples taken from people living in tent cities in our region is favorable, necessary measures should be taken against new epidemics.


Assuntos
Malária/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Malária/sangue , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Masculino , Pessoa de Meia-Idade , Recidiva , Migrantes , Viagem , Turquia/epidemiologia
11.
PLoS Negl Trop Dis ; 13(9): e0007222, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31509523

RESUMO

Plasmodium vivax invasion of human erythrocytes depends on the Duffy Binding Protein (PvDBP) which interacts with the Duffy antigen. PvDBP copy number has been recently shown to vary between P. vivax isolates in Sub-Saharan Africa. However, the extent of PvDBP copy number variation, the type of PvDBP multiplications, as well as its significance across broad samples are still unclear. We determined the prevalence and type of PvDBP duplications, as well as PvDBP copy number variation among 178 Ethiopian P. vivax isolates using a PCR-based diagnostic method, a novel quantitative real-time PCR assay and whole genome sequencing. For the 145 symptomatic samples, PvDBP duplications were detected in 95 isolates, of which 81 had the Cambodian and 14 Malagasy-type PvDBP duplications. PvDBP varied from 1 to >4 copies. Isolates with multiple PvDBP copies were found to be higher in symptomatic than asymptomatic infections. For the 33 asymptomatic samples, PvDBP was detected with two copies in two of the isolates, and both were the Cambodian-type PvDBP duplication. PvDBP copy number in Duffy-negative heterozygotes was not significantly different from that in Duffy-positives, providing no support for the hypothesis that increased copy number is a specific association with Duffy-negativity, although the number of Duffy-negatives was small and further sampling is required to test this association thoroughly.


Assuntos
Antígenos de Protozoários/genética , Variações do Número de Cópias de DNA , Malária Vivax/epidemiologia , Plasmodium vivax/genética , Proteínas de Protozoários/genética , Receptores de Superfície Celular/genética , Antígenos de Protozoários/sangue , Sistema do Grupo Sanguíneo Duffy/genética , Eritrócitos/imunologia , Eritrócitos/parasitologia , Etiópia/epidemiologia , Feminino , Genoma de Protozoário , Humanos , Malária Vivax/genética , Malária Vivax/parasitologia , Masculino , Proteínas de Protozoários/sangue , Receptores de Superfície Celular/sangue
12.
J Korean Med Sci ; 34(36): e227, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31538416

RESUMO

BACKGROUND: Vivax malaria reemerged in the Korean peninsula in 1990s beginning from the western border area and spread across both Koreas rapidly with its peak incidences reported on the early 2000s. There have been few reports on the malaria incidence in the Democratic People's Republic of Korea (North Korea) that provides detailed epidemiological features. The purpose of this study was to describe the time trends and spatial distribution of malaria in North Korea with comparison to those in South Korean regions across the border. METHODS: The incidence of malaria in each province of North Korea from 2004 to 2016 was estimated based on data from domestic and international health authorities. Consistency of the data was evaluated by calculating the ratio of malaria cases in each province to the total cases each year. We also compared the changes in malaria incidence over time in South and North Korea adjacent to the demilitarized zone. RESULTS: In North Korea, the incidence of malaria in the three provinces adjacent to the demilitarized zone was the highest (52.1-315.3 per 100,000), followed by Pyeonganbuk-do (14.7-113.5 per 100,000), where railways and road networks were connected to northern China. The incidence of malaria in each province of North Korea reported after 2011 was more consistent than when compared with previous annual data, and there was also a positive correlation between changes in incidence over time when compared with malaria incidence in South Korea (r = 0.855, r = 0.596). CONCLUSION: The malaria report of North Korea was relatively consistent in its spatiotemporal tendency since 2011, suggesting improvement of the quality of the surveillance data. The strong correlation between North and South Korean malaria incidence at regional level suggests that collaboration between both sides are essential for the successful elimination of malaria in the Korean peninsula.


Assuntos
Malária Vivax/epidemiologia , República Democrática Popular da Coreia/epidemiologia , Humanos , Incidência , Malária Vivax/diagnóstico , República da Coreia/epidemiologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-31540493

RESUMO

The future implications of climate change on malaria transmission at the global level have already been reported, however such evidences are scarce and limited in India. Here our study aims to assess, identify and map the potential effects of climate change on Plasmodium vivax (Pv) and Plasmodium falciparum (Pf) malaria transmission in India. A Fuzzy-based Climate Suitability Malaria Transmission (FCSMT) model under the GIS environment was generated using Temperature and Relative Humidity data, extracted from CORDEX South Asia for Baseline (1976-2005) and RCP 4.5 scenario for future projection by the 2030s (2021-2040). National malaria data were used at the model analysis stage. Model outcomes suggest that climate change may significantly increase the spatial spread of Pv and Pf malaria with a numerical increase in the transmission window's (TW) months, and a shift in the months of transmission. Some areas of the western Himalayan states are likely to have new foci of Pv malaria transmission. Interior parts of some southern and eastern states are likely to become more suitable for Pf malaria transmission. Study has also identified the regions with a reduction in transmission months by the 2030s, leading to unstable malaria, and having the potential for malaria outbreaks.


Assuntos
Mudança Climática , Lógica Fuzzy , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Modelos Estatísticos , Animais , Ásia/epidemiologia , Sistemas de Informação Geográfica , Humanos , Umidade , Malária Vivax/transmissão , Temperatura Ambiente
14.
J Assoc Physicians India ; 67(7): 61-64, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31559771

RESUMO

Objective: To study the incidence of thrombocytopenia in adults with Plasmodium vivax infection. Method: An observational study comprising 84 consenting individuals with Plasmodium vivax infection was undertaken. All the individuals belong to armed forces who are from different parts of the country. Everyone had normal platelet count prior to admission to the hospital. After admission, they were subjected to routine hematological and biochemical investigations comprising complete blood count including platelet counts, urine routine, liver function test, renal function test, serum electrolytes and Chest X-ray after ruling out Dengue, concomitant sepsis and possibility of recent viral infection. Grading of thrombocytopenia was done according to NCI common terminology criteria for adverse events Version 3.0. Results were analysed and tabulated. Result: A total of 84 patients were studied. 82 (97.6%) patients had thrombocytopenia. Majority (68.3%) of the patients had their lowest platelet count on the 5th and 6th day of fever. There was no associated increase in risk of complication with the increase in grade of thrombocytopenia. But with increase in severity of thrombocytopenia, it took more time for the platelets to recover to normal level. Conclusion: Thrombocytopenia is widely present in P. vivax malaria of adults. However, the severity of thrombocytopenia does not correlate with the likely progression to complication. The chance of progressing to complicated malaria is equal among all adults of P.vivax malaria irrespective of the platelet levels. Hence, in a resource limited rural Indian set-up where the expertise to diagnose and detect malaria microscopically or reliable antigen detection method is not available, thrombocytopenia in an acute febrile illness especially on Day 5 to Day 6 of fever onset could be considered as P. vivax malarial infection with good amount of diagnostic accuracy (sensitivity of 97.6%) and empirical anti-malarial therapy could be started as per the existing treatment guidelines.


Assuntos
Malária Vivax/epidemiologia , Trombocitopenia/epidemiologia , Adulto , Plaquetas , Humanos , Malária , Malária Vivax/diagnóstico , Contagem de Plaquetas
15.
Malar J ; 18(1): 262, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31366365

RESUMO

BACKGROUND: The Mindray BC-6800 haematology analyzer (BC-6800) provides a dedicated flag 'Infected RBC' (InR) and the number of InR (InR#)/the permillage of InR (InR‰) in routine blood testing as a screening tool for malaria in endemic areas. This study sought to evaluate the effectiveness of the BC-6800 flag parameter for aiding the diagnosis of malaria. METHODS: A total of 181 samples were tested using the Mindray BC-6800 haematology analyzer, including 117 malaria-infected samples collected from Yunnan, China, and 64 samples from healthy controls. Microscopy examination was conducted as reference when stained thick blood film revealed the presence of malaria parasites identified as Plasmodium vivax and Plasmodium falciparum. The receiver operating characteristic (ROC) curve analysis was developed using Analyse-it v4.92.3. The Kappa value was determined to evaluate the agreement between BC-6800 and light microscopy. RESULTS: The sensitivity of InR‰ generated by BC-6800 for P. vivax and P. falciparum was 88.3 and 24.1%, respectively; specificity of InR‰ for malaria parasites was 84.3 and 84.3%, respectively; positive predictive value and negative predictive value was 89.4 and 82.7% for P. vivax, and 52.8 and 60.3% for P. falciparum. There was a strong correlation between ΔWBC and InR‰ (R2 = 0.9731 for P. vivax and R2 = 0.9757 for P. falciparum). There was also a significant correlation between parasitaemia and InR# in P. vivax-infected samples (R2 = 0.734). InR# was evaluated using ROC curve analysis, the area under the ROC curve is 0.95 with a 95% confidence interval of 0.926 to 0.974, and the cut-off value is 0.01 × 109/L for P. vivax. However, the ring stage and the early trophozoite stage of Plasmodium cannot be detected easily on BC-6800, possibly because of the small size and low nucleic acid content of these stages. CONCLUSIONS: The findings suggest that the flag 'InR' and the parameters 'InR#/InR‰' provided by the BC-6800 haematology analyzer could be used to screen for malaria in a clinical setting.


Assuntos
Análise Química do Sangue/métodos , Sangue/parasitologia , Hematologia/métodos , Malária Falciparum/diagnóstico , Malária Vivax/diagnóstico , Plasmodium falciparum/isolamento & purificação , Plasmodium vivax/isolamento & purificação , Adolescente , Adulto , Idoso , Análise Química do Sangue/instrumentação , Criança , Pré-Escolar , China/epidemiologia , Feminino , Hematologia/instrumentação , Humanos , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Malária Vivax/epidemiologia , Malária Vivax/parasitologia , Masculino , Pessoa de Meia-Idade , Parasitemia/diagnóstico , Parasitemia/epidemiologia , Parasitemia/parasitologia , Prevalência , Curva ROC , Sensibilidade e Especificidade
16.
PLoS One ; 14(7): e0219249, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31291316

RESUMO

In this work we analyze potential environmental drivers of malaria cases in Northwestern Argentina. We inspect causal links between malaria and climatic variables by means of the convergent cross mapping technique, which provides a causality criterion from the theory of dynamic systems. Analysis is based on 12 years of weekly malaria P. vivax cases in Tartagal, Salta, Argentina-at the southern fringe of malaria incidence in the Americas-together with humidity and temperature time-series spanning the same period. Our results show that there are causal links between malaria cases and both maximum temperature, with a delay of five weeks, and minimum temperature, with delays of zero and twenty two weeks. Humidity is also a driver of malaria cases, with thirteen weeks delay between cause and effect. Furthermore we also determined the sign and strength of the effects. Temperature has always a positive non-linear effect on cases, with maximum temperature effects more pronounced above 25°C and minimum above 17°C, while effects of humidity are more intricate: maximum humidity above 85% has a negative effect, whereas minimum humidity has a positive effect on cases. These results might be signaling processes operating at short (below 5 weeks) and long (over 12 weeks) time delays, corresponding to effects related to parasite cycle and mosquito population dynamics respectively. The non-linearities found for the strength of the effect of temperature on malaria cases make warmer areas more prone to higher increases in the disease incidence. Moreover, our results indicate that an increase of extreme weather events could enhance the risks of malaria spreading and re-emergence beyond the current distribution. Both situations, warmer climate and increase of extreme events, will be remarkably increased by the end of the century in this hot spot of climate change.


Assuntos
Mudança Climática , Culicidae/patogenicidade , Malária Vivax/epidemiologia , Animais , Argentina/epidemiologia , Culicidae/fisiologia , Humanos , Umidade , Malária Vivax/parasitologia , Temperatura Ambiente
17.
Malar J ; 18(1): 230, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31291951

RESUMO

BACKGROUND: Malaria was eliminated in Spain in 1964. Since then, more than 10,000 cases of malaria have been reported, mostly in travellers and migrants, making it the most frequently imported disease into this country. In order to improve knowledge on imported malaria cases characteristics, the two main malaria data sources were assessed: the national surveillance system and the hospital discharge database (CMBD). METHODS: Observational study using prospectively gathered surveillance data and CMBD records between 2002 and 2015. The average number of hospitalizations per year was calculated to assess temporal patterns. Socio-demographic, clinical and travel background information were analysed. Bivariate and multivariable statistical methods were employed to evaluate hospitalization risk, fatal outcome, continent of infection and chemoprophylaxis failure and their association with different factors. RESULTS: A total of 9513 malaria hospital discharges and 7421 reported malaria cases were identified. The number of reported cases was below the number of hospitalizations during the whole study period, with a steady increase trend in both databases since 2008. Males aged 25-44 were the most represented in both data sources. Most frequent related co-diagnoses were anaemia (20.2%) and thrombocytopaenia (15.4%). The risks of fatal outcome increased with age and were associated with the parasite species (Plasmodium falciparum). The main place of infection was Africa (88.9%), particularly Equatorial Guinea (33.2%). Most reported cases were visiting friends and relatives (VFRs) and immigrants (70.2%). A significant increased likelihood of hospitalization was observed for children under 10 years (aOR:2.7; 95% CI 1.9-3.9), those infected by Plasmodium vivax (4.3; 95% CI 2.1-8.7) and travellers VFRs (1.4; 95% CI 1.1-1.7). Only 4% of cases reported a correct regime of chemoprophylaxis. Being male, over 15 years, VFRs, migrant and born in an endemic country were associated to increased risk of failure in preventive chemotherapy. CONCLUSIONS: The joint analysis of two data sources allowed for better characterization of imported malaria profile in Spain. Despite the availability of highly effective preventive measures, the preventable burden from malaria is high in Spain. Pre-travel advice and appropriately delivered preventive messages needs to be improved, particularly in migrants and VFRs.


Assuntos
Antimaláricos/administração & dosagem , Doenças Transmissíveis Importadas/epidemiologia , Hospitalização/estatística & dados numéricos , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Adolescente , Adulto , Fatores Etários , Quimioprevenção/estatística & dados numéricos , Doenças Transmissíveis Importadas/parasitologia , Doenças Transmissíveis Importadas/prevenção & controle , Feminino , Humanos , Incidência , Malária Falciparum/parasitologia , Malária Falciparum/prevenção & controle , Malária Vivax/parasitologia , Malária Vivax/prevenção & controle , Masculino , Pessoa de Meia-Idade , Plasmodium falciparum/fisiologia , Plasmodium vivax/fisiologia , Prevalência , Fatores de Risco , Fatores Sexuais , Espanha/epidemiologia , Viagem/estatística & dados numéricos , Adulto Jovem
18.
J Pak Med Assoc ; 69(7): 946-949, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31308559

RESUMO

OBJECTIVE: To check the prevalence of malaria in a specific geographical region. METHODS: The prospective study was conducted in Malakand, Pakistan, from January to December 2017, and comprised suspected malaria patients. Blood samples were collected during dry, rainy, and end-of-rainy season, with symptoms of malaria. Thick and thin film of blood were Giemsa-stained, stored in a secured slide box and were reconfirmed by microscopy expert at the Laboratory of District Head Quarter Hospital Batkhela and Tehsil Head Quarter Hospital Dargai in the Khyber Pakhtunkhwa province. Graph Pad 5 was used for data analysis. RESULTS: Of 1123 suspected patients, 300(26.7%) tested positive for malaria. Of the positive cases, 296(98.6%) were Plasmodium vivax and 4(1.3%) Plasmodium falciparum. No mixed-species infection and no case of Plasmodium ovale and Plasmodium malariae were reported. Malaria was higher in those aged <16 followed by those in the 33-50 group and the least in 51-80 years group (p>0.05). Males were more infected than females (p>0.05). Individuals screened in the rainy season numbered more than those in the dry and post-rain season (p<0.05).. CONCLUSIONS: Malaria was found to be highly prevalent in the rainy season.


Assuntos
Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Chuva , Estações do Ano , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Estudos Prospectivos , Distribuição por Sexo , Adulto Jovem
19.
Malar J ; 18(1): 242, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31315624

RESUMO

BACKGROUND: The importance of submicroscopic malaria infections in high-transmission areas could contribute to maintain the parasite cycle. Regarding non-endemic areas, its importance remains barely understood because parasitaemia in these afebrile patients is usually below the detection limits for microscopy, hence molecular techniques are often needed for its diagnosis. In addition to this, the lack of standardized protocols for the screening of submicroscopic malaria in immigrants from endemic areas may underestimate the infection with Plasmodium spp. The aim of this study was to assess the prevalence of submicroscopic malaria in afebrile immigrants living in a non-endemic area. METHODS: A prospective, observational, multicentre study was conducted. Afebrile immigrants were included, microscopic observation of Giemsa-stained thin and thick blood smears, and two different molecular techniques detecting Plasmodium spp. were performed. Patients with submicroscopic malaria were defined as patients with negative blood smears and detection of DNA of Plasmodium spp. with one or both molecular techniques. Demographic, clinical, analytical and microbiological features were recorded and univariate analysis by subgroups was carried out with STATA v15. RESULTS: A total of 244 afebrile immigrants were included in the study. Of them, 14 had a submicroscopic malaria infection, yielding a prevalence of 5.7% (95% confidence interval 3.45-9.40). In 71.4% of the positive PCR/negative microscopy cases, Plasmodium falciparum alone was the main detected species (10 out of the 14 patients) and in 4 cases (28.6%) Plasmodium vivax or Plasmodium ovale were detected. One patient had a mixed infection including three different species. CONCLUSIONS: The prevalence of submicroscopic malaria in afebrile immigrants was similar to that previously described in Spain. Plasmodium vivax and P. ovale were detected in almost a third of the submicroscopic infections. Screening protocols for afebrile immigrants with molecular techniques could be useful for a proper management of these patients.


Assuntos
Doenças Assintomáticas/epidemiologia , Malária/epidemiologia , Plasmodium falciparum/isolamento & purificação , Plasmodium ovale/isolamento & purificação , Plasmodium vivax/isolamento & purificação , Adulto , Coinfecção/epidemiologia , Coinfecção/parasitologia , Emigrantes e Imigrantes , Feminino , Humanos , Malária/parasitologia , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Malária Vivax/epidemiologia , Malária Vivax/parasitologia , Masculino , Microscopia , Pessoa de Meia-Idade , Prevalência , Espanha/epidemiologia
20.
Parasit Vectors ; 12(1): 374, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31358033

RESUMO

BACKGROUND: Malaria remains an important public health problem in Peru where incidence has been increasing since 2011. Of over 55,000 cases reported in 2017, Plasmodium vivax was the predominant species (76%), with P. falciparum responsible for the remaining 24%. Nyssorhynchus darlingi (previously Anopheles darlingi) is the main vector in Amazonian Peru, where hyperendemic Plasmodium transmission pockets have been found. Mazán district has pronounced spatial heterogeneity of P. vivax malaria. However, little is known about behavior, ecology or seasonal dynamics of Ny. darlingi in Mazán. This study aimed to gather baseline information about bionomics of malaria vectors and transmission risk factors in a hyperendemic malaria area of Amazonian Peru. METHODS: To assess vector biology metrics, five surveys (two in the dry and three in the rainy season), including collection of sociodemographic information, were conducted in four communities in 2016-2017 on the Napo (Urco Miraño, URC; Salvador, SAL) and Mazán Rivers (Visto Bueno, VIB; Libertad, LIB). Human-biting rate (HBR), entomological inoculation rate (EIR) and human blood index (HBI) were measured to test the hypothesis of differences in entomological indices of Ny. darlingi between watersheds. A generalized linear mixed effect model (GLMM) was constructed to model the relationship between household risk factors and the EIR. RESULTS: Nyssorhynchus darlingi comprised 95% of 7117 Anophelinae collected and its abundance was significantly higher along the Mazán River. The highest EIRs (3.03-4.54) were detected in March and June in URC, LIB and VIB, and significantly more Ny. darlingi were infected outdoors than indoors. Multivariate analysis indicated that the EIR was >12 times higher in URC compared with SAL. The HBI ranged from 0.42-0.75; humans were the most common blood source, followed by Galliformes and cows. There were dramatic differences in peak biting time and malaria incidence with similar bednet coverage in the villages. CONCLUSIONS: Nyssorhynchus darlingi is the predominant contributor to malaria transmission in the Mazán District, Peru. Malaria risk in these villages is higher in the peridomestic area, with pronounced heterogeneities between and within villages on the Mazán and the Napo Rivers. Spatiotemporal identification and quantification of the prevailing malaria transmission would provide new evidence to orient specific control measures for vulnerable or at high risk populations.


Assuntos
Anopheles/fisiologia , Anopheles/parasitologia , Habitação , Malária/transmissão , Mosquitos Vetores/parasitologia , Rios , Adolescente , Adulto , Animais , Mordeduras e Picadas , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Malária/epidemiologia , Malária Falciparum/epidemiologia , Malária Falciparum/transmissão , Malária Vivax/epidemiologia , Malária Vivax/transmissão , Masculino , Peru/epidemiologia , Fatores de Risco , Estações do Ano , Adulto Jovem
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