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1.
BMJ Paediatr Open ; 8(1)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38906562

RESUMO

We conducted a propensity score-matched multivariable regression analysis of 1050 culture-negative neonatal sepsis cases in Malawi, where 160 (15.2%) died. Mortality among neonates with culture-negative sepsis was associated with very low birth weight (adjusted OR (AOR) 12.82, 95% CI 1.23 to 137.49), respiratory distress syndrome (AOR 13.20, 95% CI 2.58 to 83.66), a low Apgar score at 1 min (AOR 3.50, 95% CI 1.21 to 10.72) and at 5 min (AOR 4.77, 95% CI 1.94 to 12.50). Addressing maternal and perinatal factors around health and delivery of care is key to improving outcomes in the context of culture-negative sepsis in neonates from low-income country settings like Malawi.


Assuntos
Sepse Neonatal , Pontuação de Propensão , Humanos , Malaui/epidemiologia , Recém-Nascido , Sepse Neonatal/mortalidade , Feminino , Fatores de Risco , Masculino , Índice de Apgar , Recém-Nascido de muito Baixo Peso , Síndrome do Desconforto Respiratório do Recém-Nascido/mortalidade
2.
PLOS Glob Public Health ; 4(3): e0002369, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38498477

RESUMO

The widespread use of antigen-detection rapid diagnostic tests (Ag-RDTs) has revolutionized SARS-CoV-2 (COVID-19) testing, particularly through the option of self-testing. The full extent of Ag-RDT utilization for self-testing, however, remains largely unexplored. To inform the development of WHO guidance on COVID-19 self-testing, we conducted a global consultation to gather the views and experiences of policy makers, researchers, and implementers worldwide. The consultation was conducted by disseminating a WHO questionnaire through professional networks via email and social media, encouraging onward sharing. We used a cross-sectional design with both closed and open-ended questions related to policy and program information concerning the regulation, availability, target population, indications, implementation, benefits, and challenges of COVID-19 self-testing (C19ST). We defined self-testing as tests performed and interpreted by an untrained individual, often at home. Descriptive summaries, cross-tabulations, and proportions were used to calculate outcomes at the global level and by WHO region and World Bank income classifications. All information was collated and reported according to WHO guideline development standards and practice for global consultations. Between 01 and 11 February 2022, 844 individuals from 139 countries responded to the survey, with 45% reporting affiliation with governments and 47% operating at the national level. 504 respondents from 101 countries reported policies supporting C19ST for a range of use cases, including symptomatic and asymptomatic populations. More respondents from low-and-middle-income countries (LMICs) than high-income countries (HICs) reported a lack of an C19ST policy (61 vs 11 countries) and low population-level reach of C19ST. Respondents with C19ST experience perceived that the tests were mostly acceptable to target populations, provided significant benefits, and highlighted several key challenges to be addressed for increased success. Reported costs varied widely, ranging from specific programmes enabling free access to certain users and others with high costs via the private sector. Based on this consultation, systems for the regulatory review, policy development and implementation of C19ST appeared to be much more common in HIC when compared to LIC in early 2022, though most respondents indicated self-testing was available to some extent (101 out of 139 countries) in their country. Addressing such global inequities is critical for ensuring access to innovative and impactful interventions in the context of a public health emergency of international concern. The challenges and opportunities highlighted by key stakeholders could be valuable to consider as future testing strategies are being set for outbreak-prone diseases.

3.
Environ Monit Assess ; 195(10): 1247, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37750982

RESUMO

We set out to reveal the effects of long-term changes in land use and long-term average climate on the regional biophysical environment in southern Malawi. Object-oriented supervised image classification was performed on Landsat 5 and 8 satellite images from 1990 to 2020 to identify and quantify past and present land use-land cover changes using a support vector machine classifier. Subsequently, using 2000 and 2010 land use-land cover in an artificial neural network, land use-land cover for 2020 driven by elevation, slope, precipitation and temperature, population density, poverty, distance to major roads, and distance to villages data was simulated. Between 1990 and 2020, area of land cover increased in built-up (209%), bare land (10%), and cropland (10%) and decreased in forest (30%), herbaceous (4%), shrubland (20%), and water area (20%). Overall, the findings reveal that southern Malawi is dominantly an agro-mosaic landscape shaped by the combined effects of urban and agricultural expansions and climate. The findings also suggest the need to enhance the machine learning algorithms to improve capacity for landscape modelling and, ultimately, prevention, preparedness, and response to environmental risks.


Assuntos
Clima , Monitoramento Ambiental , Malaui , Temperatura , Agricultura
4.
Malar J ; 22(1): 246, 2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37633902

RESUMO

BACKGROUND: In Malawi, malaria is responsible for 40% of hospital deaths. Prompt diagnosis and effective treatment within 24 h of fever onset is critical to prevent progression from uncomplicated to severe disease and to reduce transmission. METHODS: As part of the large evaluation of the malaria vaccine implementation programme (MVIP), this study analysed survey data to investigate whether prompt treatment-seeking behaviour is clustered at community-level according to socio-economic demographics. RESULTS: From 4563 households included in the survey, 4856 children aged 5-48 months were enrolled. Out of 4732 children with documented gender, 52.2% were female and 47.8% male. Among the 4856 children, 33.8% reported fever in the two weeks prior to the survey. Fever prevalence was high in communities with low socio-economic status (SES) (38.3% [95% CI: 33.7-43.5%]) and low in areas with high SES (29.8% [95% CI: 25.6-34.2%]). Among children with fever, 648 (39.5%) sought treatment promptly i.e., within 24 h from onset of fever symptoms. Children were more likely to be taken for prompt treatment among guardians with secondary education compared to those without formal education (aOR:1.37, 95% CI: 1.11-3.03); in communities with high compared to low SES [aOR: 2.78, 95% CI: 1.27-6.07]. Children were less likely to be taken for prompt treatment if were in communities far beyond 5 km to health facility than within 5 km [aOR: 0.44, 95% CI: 0.21-0.92]. CONCLUSION: The high heterogeneity in prevalence of fever and levels of prompt treatment-seeking behaviour underscore the need to promote community-level malaria control interventions (such as use of long-lasting insecticide-treated nets (LLINs), indoor residual spraying (IRS), intermittent preventive therapy (IPT), presumptive treatment and education). Programmes aimed at improving treatment-seeking behaviour should consider targeting communities with low SES and those far from health facility.


Assuntos
Vacinas Antimaláricas , Malária , Desnutrição , Humanos , Criança , Feminino , Masculino , Malaui/epidemiologia , Malária/tratamento farmacológico , Malária/epidemiologia , Malária/prevenção & controle , Escolaridade , Febre/epidemiologia
5.
Wellcome Open Res ; 8: 178, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37600585

RESUMO

Background: Malawi's National Malaria Control Programme (NMCP) is developing a new strategic plan for 2023-2030 to combat malaria and recognizes that a blanket approach to malaria interventions is no longer feasible. To inform this new strategy, the NMCP set up a task force comprising 18 members from various sectors, which convened a meeting to stratify the malaria burden in Malawi and recommend interventions for each stratum. Methods: The burden stratification workshop took place from November 29 to December 2, 2022, in Blantyre, Malawi, and collated essential data on malaria burden indicators, such as incidence, prevalence, and mortality. Workshop participants reviewed the malaria burden and intervention coverage data to describe the current status and identified the districts as a appropriate administrative level for stratification and action. Two scenarios were developed for the stratification, based on composites of three variables. Scenario 1 included incidence, prevalence, and under-five all-cause mortality, while Scenario 2 included total malaria cases, prevalence, and under-five all-cause mortality counts. The task force developed four burden strata (highest, high, moderate, and low) for each scenario, resulting in a final list of districts assigned to each stratum. Results: The task force concluded with 10 districts in the highest-burden stratum (Nkhotakota, Salima, Mchinji, Dowa, Ntchisi, Mwanza, Likoma, Lilongwe, Kasungu and Mangochi) 11 districts in the high burden stratum (Chitipa, Rumphi, Nkhata Bay, Dedza, Ntcheu, Neno, Thyolo, Nsanje, Zomba, Mzimba and Mulanje) and seven districts in the moderate burden stratum (Karonga, Chikwawa, Balaka, Machinga, Phalombe, Blantyre, and Chiradzulu). There were no districts in the low-burden stratum. Conclusion: The next steps for the NMCP are to review context-specific issues driving malaria transmission and recommend interventions for each stratum. Overall, this burden stratification workshop provides a critical foundation for developing a successful malaria strategic plan for Malawi.

6.
Artigo em Inglês | MEDLINE | ID: mdl-37577134

RESUMO

Infectious diseases are emerging at an unprecedented rate while food production intensifies to keep pace with population growth. Large-scale irrigation schemes have the potential to permanently transform the landscape with health, nutritional and socio-economic benefits; yet, this also leads to a shift in land-use patterns that can promote endemic and invasive insect vectors and pathogens. The balance between ensuring food security and preventing emerging infectious disease is a necessity; yet the impact of irrigation on vector-borne diseases at the epidemiological, entomological and economic level is uncertain and depends on the geographical and climatological context. Here, we highlight the risk factors and challenges facing vector-borne disease surveillance and control in an emerging agricultural ecosystem in the lower Shire Valley region of southern Malawi. A phased large scale irrigation programme (The Shire Valley Transformation Project, SVTP) promises to transform over 40,000 ha into viable and resilient farmland, yet the valley is endemic for malaria and schistosomiasis and experiences frequent extreme flooding events following tropical cyclones. The latter exacerbate vector-borne disease risk while simultaneously making any empirical assessment of that risk a significant hurdle. We propose that the SVTP provides a unique opportunity to take a One Health approach at mitigating vector-borne disease risk while maintaining agricultural output. A long-term and multi-disciplinary approach with buy-in from multiple stakeholders will be needed to achieve this goal.

7.
BMJ Open ; 13(5): e069560, 2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-37173105

RESUMO

INTRODUCTION: Vaccination is a potentially critical component of efforts to arrest development and dissemination of antimicrobial resistance (AMR), though little is known about vaccination impact within low-income and middle-income countries. This study will evaluate the impact of vaccination on reducing carriage prevalence of resistant Streptococcus pneumoniae and extended spectrum beta-lactamase-producing Escherichia coli and Klebsiella species. We will leverage two large ongoing cluster-randomised vaccine evaluations in Malawi assessing; first, adding a booster dose to the 13-valent pneumococcal conjugate vaccine (PCV13) schedule, and second, introduction of the RTS,S/AS01 malaria vaccine. METHODS AND ANALYSIS: Six cross-sectional surveys will be implemented within primary healthcare centres (n=3000 users of outpatient facilities per survey) and their local communities (n=700 healthy children per survey): three surveys in Blantyre district (PCV13 component) and three surveys in Mangochi district (RTS,S/AS01 component). We will evaluate antibiotic prescription practices and AMR carriage in children ≤3 years. For the PCV13 component, surveys will be conducted 9, 18 and 33 months following a 3+0 to 2+1 schedule change. For the RTS,S/AS01 component, surveys will be conducted 32, 44 and 56 months post-RTS,S/AS01 introduction. Six health centres in each study component will be randomly selected for study inclusion. Between intervention arms, the primary outcome will be the difference in penicillin non-susceptibility prevalence among S. pneumoniae nasopharyngeal carriage isolates in healthy children. The study is powered to detect an absolute change of 13 percentage points (ie, 35% vs 22% penicillin non-susceptibility). ETHICS AND DISSEMINATION: This study has been approved by the Kamuzu University of Health Sciences (Ref: P01-21-3249), University College London (Ref: 18331/002) and University of Liverpool (Ref: 9908) Research Ethics Committees. Parental/caregiver verbal or written informed consent will be obtained prior to inclusion or recruitment in the health centre-based and community-based activities, respectively. Results will be disseminated via the Malawi Ministry of Health, WHO, peer-reviewed publications and conference presentations.


Assuntos
Vacinas Antimaláricas , Malária , Infecções Pneumocócicas , Humanos , Criança , Lactente , Pré-Escolar , Streptococcus pneumoniae , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/prevenção & controle , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Estudos Transversais , Malaui/epidemiologia , Farmacorresistência Bacteriana , Vacinas Pneumocócicas , Vacinação , Penicilinas , Nasofaringe , Malária/epidemiologia , Malária/prevenção & controle , Portador Sadio/epidemiologia
8.
PLoS Negl Trop Dis ; 17(5): e0010654, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37141380

RESUMO

BACKGROUND: Fishing exposes fishermen to schistosomiasis-infested fresh water and concurrently through precarious livelihoods to risky sexual behaviour, rendering these two infections occupational hazards for fishermen. This study aimed to characterize the knowledge of the two conditions to obtain necessary data for a subsequent cluster randomized trial designed to investigate demand creation strategies for joint HIV-schistosomiasis service provision in fishing villages on the shores of southern Lake Malawi. METHODS: Enumeration of all resident fishermen in 45 clusters (fishing communities) was carried out between November 2019 and February 2020. In a baseline survey, fishermen reported their knowledge, attitudes and practices in the uptake of HIV and schistosomiasis services. Knowledge of HIV status and previous receipt of praziquantel were modelled using random effects binomial regression, accounting for clustering. Prevalence of willingness to attend a beach clinic was computed. RESULTS: A total of 6,297 fishermen were surveyed from the 45 clusters with harmonic mean number of fishermen per cluster of 112 (95% CI: 97; 134). The mean age was 31.7y (SD: 11.9) and nearly 40% (2,474/6,297) could not read or write. Overall, 1,334/6,293 (21.2%) had never tested for HIV, with 64.4% (3,191/4,956) having tested in the last 12 months, and 5.9% (373/6290) taking antiretroviral therapy (ART). In adjusted analyses, being able to read and write (adjusted risk ratio [aRR: 1.91, 95% CI: 1.59-2.29, p<0.001); previous use of praziquantel (aRR: 2.00,95% CI: 1.73-2.30, p<0.001); knowing a relative or friend who died of HIV (aRR: 1.54,95% CI: 1.33-1.79, p<0.001); and being on ART (aRR: 12.93, 95% CI: 6.25-32.93, p<0.001) were associated with increased likelihood of ever testing for HIV. Only 40% (1,733/4,465) had received praziquantel in the last 12 months. Every additional year of age was associated with 1% decreased likelihood of having taken praziquantel in the last 12 months (aRR: 0.99, 95% CI: 0.98-0.99, p<0.001). However, recent HIV testing increased the likelihood of taking praziquantel by over 2-fold (aRR 2.24, 95% CI: 1.93-2.62, p<0.001). Willingness to attend a mobile beach clinic offering integrated HIV and schistosomiasis services was extremely high at 99.0% (6,224/6,284). CONCLUSION: In a setting with an underlying high prevalence of both HIV and schistosomiasis, we found low knowledge of HIV status and low utilization of free schistosomiasis treatment. Among fishermen who accessed HIV services, there was a very high likelihood of taking praziquantel suggesting that integrated service delivery may lead to good coverage. TRIAL REGISTRATION: This trial is registered in the ISRCTN registry: ISRCTN14354324; date of registration: 05 October 2020.


Assuntos
Infecções por HIV , Esquistossomose , Humanos , Praziquantel/uso terapêutico , Malaui/epidemiologia , Esquistossomose/diagnóstico , Esquistossomose/tratamento farmacológico , Esquistossomose/epidemiologia , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Teste de HIV , Inquéritos e Questionários
9.
Wellcome Open Res ; 8: 264, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38756913

RESUMO

Background: Malaria remains a public health problem in Malawi and has a serious socio-economic impact on the population. In the past two decades, available malaria control measures have been substantially scaled up, such as insecticide-treated bed nets, artemisinin-based combination therapies, and, more recently, the introduction of the malaria vaccine, the RTS,S/AS01. In this paper, we describe the epidemiology of malaria for the last two decades to understand the past transmission and set the scene for the elimination agenda. Methods: A collation of parasite prevalence surveys conducted between the years 2000 and 2022 was done. A spatio-temporal geostatistical model was fitted to predict the yearly malaria risk for children aged 2-10 years (PfPR 2-10) at 1×1 km spatial resolutions. Parameter estimation was done using the Monte Carlo maximum likelihood method. District-level prevalence estimates adjusted for population are calculated for the years 2000 to 2022. Results: A total of 2,595 sampled unique locations from 2000 to 2022 were identified through the data collation exercise. This represents 70,565 individuals that were sampled in the period. In general, the PfPR2_10 declined over the 22 years. The mean modelled national PfPR2_10 in 2000 was 43.93 % (95% CI:17.9 to 73.8%) and declined to 19.2% (95%CI 7.49 to 37.0%) in 2022. The smoothened estimates of PfPR2_10 indicate that malaria prevalence is very heterogeneous with hotspot areas concentrated on the southern shores of Lake Malawi and the country's central region. Conclusions: The last two decades are associated with a decline in malaria prevalence, highly likely associated with the scale-up of control interventions. The country should move towards targeted malaria control approaches informed by surveillance data.


In Malawi, malaria continues to be a significant health issue, affecting people's well-being and the economy. Over the past twenty years, efforts to control malaria, such as using bed nets, specific medications, and introducing a malaria vaccine, have increased substantially. This paper explores malaria transmission patterns during this time to better understand the past situation and prepare for future efforts to eliminate the disease. We collected and analyzed data from various surveys conducted between 2000 and 2022, focusing on malaria risk for children aged 2­10 years. We used a detailed statistical model to predict yearly malaria risk. The results show a decline in malaria prevalence over the 22 years. The analysis also reveals variations in malaria prevalence, with hotspot areas particularly concentrated in the southern shores of Lake Malawi and the country's central region. This decline in malaria prevalence is likely linked to the increased implementation of control measures. The findings emphasize the importance of targeted approaches informed by ongoing surveillance data for continued progress in malaria control.

10.
Front Public Health ; 11: 1242870, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38292384

RESUMO

Background: Mother-to-child transmission of syphilis remains high especially in the WHO AFRO region with a prevalence of 1.62%, resulting in a congenital syphilis rate of 1,119 per 100,000 live births. Elimination efforts can be supported by an understanding of the spatial and temporal changes in disease over time, which can identify priority areas for targeted interventions aimed at reducing transmission. Methods: We collated routine surveillance data from health facilities and covariate data from demographic and health surveys conducted in Malawi between 2014 and 2022. We fitted a Bayesian hierarchical mixed model with spatial and temporally structured random effects to model the district-level monthly counts of maternal syphilis notifications as a function of individual- and district-level predictors. We then generated district-level spatiotemporally explicit risk profiles to estimate the effect of individual- and district-level covariates on maternal syphilis notifications and to identify hotspot areas. Results: Overall, the national prevalence of maternal syphilis increased from 0.28% (95% CI: 0.27-0.29%) in 2014 to peaking in 2021 at 1.92% (95% CI: 1.89-1.96%). Between 2020 and 2022, there was a decline in prevalence, with the most significant decline seen in Zomba District (1.40, 95% CI: 1.12-1.66%). In regression models, a one percentage point increase in district-level antenatal HIV prevalence was associated with increased maternal syphilis (prevalence ratio [PR]: 1.15, 95% credible interval [CrI]: 1.10-1.21). There was also an increased prevalence of maternal syphilis associated with an increased district-level mean number of sex partners (PR: 1.05, 95% CrI: 0.80-1.37). The number of districts with a high prevalence of maternal syphilis also increased between 2014 and 2022, especially in the southern region, where most had a high probability (approaching 100%) of having high maternal syphilis (defined as relative risk >1 compared to the standard population of women aged 15-49 years) in 2022. Conclusion: Maternal syphilis prevalence in Malawi shows an increasing upward trend, with an estimated six times relative increase between 2014 and 2022 (0.28% to 1.73%) and strong associations with higher district-level HIV prevalence. Controlling syphilis depends on reaching vulnerable populations at the sub-national level, which may be disproportionately affected. Our findings support the move to integrate the elimination of mother-to-child transmission (EMTCT) of syphilis programs with existing prevention of mother-to-child transmission (PMTCT) of HIV programs.


Assuntos
Infecções por HIV , Complicações Infecciosas na Gravidez , Sífilis , Gravidez , Feminino , Humanos , Sífilis/epidemiologia , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/prevenção & controle , Prevalência , Malaui/epidemiologia , Teorema de Bayes , Transmissão Vertical de Doenças Infecciosas
11.
Sci Rep ; 12(1): 3428, 2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-35236911

RESUMO

Irrigation schemes provide an ideal habitat for Anopheles mosquitoes particularly during the dry season. Reliable estimates of outdoor host-seeking behaviour are needed to assess the impact of vector control options and this is particularly the case for Anopheles arabiensis which displays a wide range of behaviours that circumvent traditional indoor-insecticide based control. In this study we compared the sampling efficiency of the host decoy trap (HDT) with the human landing catch (HLC) and Suna trap in a repeated Latin square design in two villages (Lengwe and Mwanza) on an irrigated sugar estate in southern Malawi. Over the course of 18 trapping nights, we caught 379 female Anopheles, the majority of which were identified as An. arabiensis. Across both villages, there was no detectable difference in Anopheles catch between the HDT compared with the HLC (RR = 0.85, P = 0.508). The overall sensitivity of the HLC was greater than the Suna trap regardless of mosquito density (Lengwe, α = 2.75, 95% credible interval: 2.03-3.73; Mwanza, α = 3.38, 95% credible interval: 1.50-9.30) whereas the sensitivity of the HDT was only greater than the Suna trap when mosquito numbers were high (Lengwe, α = 2.63, 95% credible interval: 2.00-3.85).We conclude that the HDT is an effective sampling device for outdoor host seeking An. arabiensis in southern Malawi. The presence of An. arabiensis in irrigated lands during the dry season poses a challenge for ongoing indoor vector control efforts.


Assuntos
Anopheles , Controle de Mosquitos , Animais , Entomologia , Feminino , Humanos , Malaui , Mosquitos Vetores
12.
BMJ Open ; 12(2): e050188, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35135765

RESUMO

OBJECTIVE: Assess characteristics of clinical pneumonia after introduction of pneumococcal conjugate vaccine (PCV), by HIV exposure status, in children hospitalised in a governmental hospital in Malawi. METHODS AND FINDINGS: We evaluated 1139 children ≤5 years old hospitalised with clinical pneumonia: 101 HIV-exposed, uninfected (HEU) and 1038 HIV-unexposed, uninfected (HUU). Median age was 11 months (IQR 6-20), 59% were male, median mid-upper arm circumference (MUAC) was 14 cm (IQR 13-15) and mean weight-for-height z score was -0.7 (±2.5). The highest Respiratory Index of Severity in Children (RISC) scores were allocated to 10.4% of the overall cohort. Only 45.7% had fever, and 37.2% had at least one danger sign at presentation. The most common clinical features were crackles (54.7%), nasal flaring (53.5%) and lower chest wall indrawing (53.2%). Compared with HUU, HEU children were significantly younger (9 months vs 11 months), with lower mean birth weight (2.8 kg vs 3.0 kg) and MUAC (13.6 cm vs 14.0 cm), had higher prevalence of vomiting (32.7% vs 22.0%), tachypnoea (68.4% vs 49.8%) and highest RISC scores (20.0% vs 9.4%). Five children died (0.4%). However, clinical outcomes were similar for both groups. CONCLUSIONS: In this post-PCV setting where prevalence of HIV and malnutrition is high, children hospitalised fulfilling the WHO Integrated Management of Childhood Illness criteria for clinical pneumonia present with heterogeneous features. These vary by HIV exposure status but this does not influence either the frequency of danger signs or mortality. The poor performance of available severity scores in this population and the absence of more specific diagnostics hinder appropriate antimicrobial stewardship and the rational application of other interventions.


Assuntos
Infecções por HIV , Pneumonia , Criança , Criança Hospitalizada , Pré-Escolar , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Hospitais , Humanos , Lactente , Malaui/epidemiologia , Masculino , Pneumonia/epidemiologia , Estudos Prospectivos , Vacinas Conjugadas
13.
Wellcome Open Res ; 7: 251, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36874568

RESUMO

Background: Air pollution is a major environmental risk factor for cardiorespiratory disease. Exposures to household air pollution from cooking and other activities, are particularly high in Southern Africa. Following an extended period of participant observation in a village in Malawi, we aimed to assess individuals' exposures to fine particulate matter (PM 2.5) and carbon monoxide (CO) and to investigate the different sources of exposure, including different cooking methods. Methods: Adult residents of a village in Malawi wore personal PM 2.5 and CO monitors for 24-48 hours, sampling every 1 (CO) or 2 minutes (PM 2.5). Subsequent in-person interviews recorded potential exposure details over the time periods. We present means and interquartile ranges for overall exposures and summaries stratified by time and activity (exposure). We employed multivariate regression to further explore these characteristics, and Spearman rank correlation to examine the relationship between paired PM 2.5 and CO exposures. Results : Twenty participants (17 female; median age 40 years, IQR: 37-56) provided 831 hours of paired PM 2.5 and CO data. Concentrations of PM 2.5 during combustion activity, usually cooking, far exceeded background levels (no combustion activity): 97.9µg/m 3 (IQR: 22.9-482.0), vs 7.6µg/m 3, IQR: 2.5-20.6 respectively. Background PM 2.5 concentrations were higher during daytime hours (11.7µg/m 3 [IQR: 5.2-30.0] vs 3.3µg/m 3 at night [IQR: 0.7-8.2]). Highest exposures were influenced by cooking location but associated with charcoal use (for CO) and firewood on a three-stone fire (for PM 2.5). Cooking-related exposures were higher in more ventilated places, such as outside the household or on a walled veranda, than during indoor cooking. Conclusions : The study demonstrates the value of combining personal PM 2.5 exposure data with detailed contextual information for providing deeper insights into pollution sources and influences. The finding of similar/lower exposures during cooking in seemingly less-ventilated places should prompt a re-evaluation of proposed clean air interventions in these settings.

14.
Wellcome Open Res ; 6: 21, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722933

RESUMO

Preterm birth is the leading cause of infant death worldwide, but the causes of preterm birth are largely unknown. During the early COVID-19 lockdowns, dramatic reductions in preterm birth were reported; however, these trends may be offset by increases in stillbirth rates. It is important to study these trends globally as the pandemic continues, and to understand the underlying cause(s). Lockdowns have dramatically impacted maternal workload, access to healthcare, hygiene practices, and air pollution - all of which could impact perinatal outcomes and might affect pregnant women differently in different regions of the world. In the international Perinatal Outcomes in the Pandemic (iPOP) Study, we will seize the unique opportunity offered by the COVID-19 pandemic to answer urgent questions about perinatal health. In the first two study phases, we will use population-based aggregate data and standardized outcome definitions to: 1) Determine rates of preterm birth, low birth weight, and stillbirth and describe changes during lockdowns; and assess if these changes are consistent globally, or differ by region and income setting, 2) Determine if the magnitude of changes in adverse perinatal outcomes during lockdown are modified by regional differences in COVID-19 infection rates, lockdown stringency, adherence to lockdown measures, air quality, or other social and economic markers, obtained from publicly available datasets. We will undertake an interrupted time series analysis covering births from January 2015 through July 2020. The iPOP Study will involve at least 121 researchers in 37 countries, including obstetricians, neonatologists, epidemiologists, public health researchers, environmental scientists, and policymakers. We will leverage the most disruptive and widespread "natural experiment" of our lifetime to make rapid discoveries about preterm birth. Whether the COVID-19 pandemic is worsening or unexpectedly improving perinatal outcomes, our research will provide critical new information to shape prenatal care strategies throughout (and well beyond) the pandemic.

15.
BMJ Open ; 11(6): e050312, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140345

RESUMO

INTRODUCTION: Streptococcus pneumoniae (the pneumococcus) is commonly carried as a commensal bacterium in the nasopharynx but can cause life-threatening disease. Transmission occurs by human respiratory droplets and interruption of this process provides herd immunity. A 2017 WHO Consultation on Optimisation of pneumococcal conjugate vaccines (PCV) Impact highlighted a substantial research gap in investigating why the impact of PCV vaccines in low-income countries has been lower than expected. Malawi introduced the 13-valent PCV (PCV13) into the national Expanded Programme of Immunisations in 2011, using a 3+0 (3 primary +0 booster doses) schedule. With evidence of greater impact of a 2+1 (2 primary +1 booster dose) schedule in other settings, including South Africa, Malawi's National Immunisations Technical Advisory Group is seeking evidence of adequate superiority of a 2+1 schedule to inform vaccine policy. METHODS: A pragmatic health centre-based evaluation comparing impact of a PCV13 schedule change from 3+0 to 2+1 in Blantyre district, Malawi. Twenty government health centres will be randomly selected, with ten implementing a 2+1 and 10 to continue with the 3+0 schedule. Health centres implementing 3+0 will serve as the direct comparator in evaluating 2+1 providing superior direct and indirect protection against pneumococcal carriage. Pneumococcal carriage surveys will evaluate carriage prevalence among children 15-24 months, randomised at household level, and schoolgoers 5-10 years of age, randomly selected from school registers. Carriage surveys will be conducted 18 and 33 months following 2+1 implementation. ANALYSIS: The primary endpoint is powered to detect an effect size of 50% reduction in vaccine serotype (VT) carriage among vaccinated children 15-24 months old, expecting a 14% and 7% VT carriage prevalence in the 3+0 and 2+1 arms, respectively. ETHICS AND DISSEMINATION: The study has been approved by the Malawi College of Medicine Research Ethics Committee (COMREC; Ref: P05.19.2680), the University College London Research Ethics Committee (Ref: 8603.002) and the University of Liverpool Research Ethics Committee (Ref: 5439). The results from this study will be actively disseminated through manuscript publications and conference presentations. TRIAL REGISTRATION NUMBER: NCT04078997.


Assuntos
Infecções Pneumocócicas , Streptococcus pneumoniae , Portador Sadio/epidemiologia , Criança , Pré-Escolar , Efeitos Psicossociais da Doença , Humanos , Lactente , Londres , Malaui/epidemiologia , Nasofaringe , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas , África do Sul , Vacinas Conjugadas
16.
BMJ Glob Health ; 5(11)2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33214176

RESUMO

Adults admitted to hospital with critical illness are vulnerable and at high risk of morbidity and mortality, especially in sub-Saharan African settings where resources are severely limited. As life expectancy increases, patient demographics and healthcare needs are increasingly complex and require integrated approaches. Patient outcomes could be improved by increased critical care provision that standardises healthcare delivery, provides specialist staff and enhanced patient monitoring and facilitates some treatment modalities for organ support. In Malawi, we established a new high-dependency unit within Queen Elizabeth Central Hospital, a tertiary referral centre serving the country's Southern region. This unit was designed in partnership with managers, clinicians, nurses and patients to address their needs. In this practice piece, we describe a participatory approach to design and implement a sustainable high-dependency unit for a low-income sub-Saharan African setting. This included: prospective agreement on remit, alignment with existing services, refurbishment of a dedicated physical space, recruitment and training of specialist nurses, development of context-sensitive clinical standard operating procedures, purchase of appropriate and durable equipment and creation of digital clinical information systems. As the global COVID-19 pandemic unfolded, we accelerated unit opening in anticipation of increased clinical requirement and describe how the high-dependency unit responded to this demand.


Assuntos
COVID-19 , Unidades Hospitalares , Centros de Atenção Terciária , COVID-19/enfermagem , COVID-19/prevenção & controle , COVID-19/terapia , Enfermagem de Cuidados Críticos/educação , Enfermagem de Cuidados Críticos/organização & administração , Estado Terminal/terapia , Arquitetura Hospitalar , Humanos , Malaui , Qualidade da Assistência à Saúde , Encaminhamento e Consulta
17.
Acta Trop ; 210: 105558, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32485166

RESUMO

INTRODUCTION: Increasing the knowledgebase of anopheline larval ecology could enable targeted deployment of malaria control efforts and consequently reduce costs of implementation. In Malawi, there exists a knowledge gap in anopheline larval ecology and, therefore, basis for targeted deployment of larval source management (LSM) for malaria control, specifically larvicides. We set out to characterize anopheline larval habitats in the Majete area of Malawi on the basis of habitat ecology and anopheline larval productivity to create a basis for larval control initiatives in the country. METHODS: Longitudinal surveys were conducted in randomly selected larval habitats over a period of fifteen months in Chikwawa district, southern Malawi. Biotic and abiotic parameters of the habitats were modelled to determine their effect on the occurrence and densities of anopheline larvae. RESULTS: Seventy aquatic habitats were individually visited between 1-7 times over the study period. A total of 5,123 immature mosquitoes (3,359 anophelines, 1,497 culicines and 267 pupae) were collected. Anopheline and culicine larvae were observed in sympatry in aquatic habitats. Of the nine habitat types followed, dams, swamps, ponds, borehole runoffs and drainage channels were the five most productive habitat types for anopheline mosquitoes. Anopheline densities were higher in aquatic habitats with bare soil making up part of the surrounding land cover (p<0.01) and in aquatic habitats with culicine larvae (p<0.01) than in those surrounded by vegetation and not occupied by culicine larvae. Anopheline densities were significantly lower in highly turbid habitats than in clearer habitats (p<0.01). Presence of predators in the aquatic habitats significantly reduced the probability of anopheline larvae being present (p=0.04). CONCLUSIONS: Anopheline larval habitats are widespread in the study area. Presence of bare soil, culicine larvae, predators and the level of turbidity of water are the main determinants of anopheline larval densities in aquatic habitats in Majete, Malawi. While the most productive aquatic habitats should be prioritised, for the most effective control of vectors in the area all available aquatic habitats should be targeted, even those that are not characterized by the identified predictors. Further research is needed to determine whether targeted LSM would be cost-effective when habitat characterisation is included in cost analyses and to establish what methods would make the characterisation of habitats easier.


Assuntos
Anopheles/crescimento & desenvolvimento , Ecossistema , Malária/transmissão , Mosquitos Vetores/crescimento & desenvolvimento , Animais , Larva/crescimento & desenvolvimento , Malária/prevenção & controle , Malaui , Controle de Mosquitos/métodos
18.
Parasit Vectors ; 13(1): 259, 2020 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-32416733

RESUMO

BACKGROUND: Application of the larvicide Bacillus thuringiensis var. israelensis (Bti) is a viable complementary strategy for malaria control. Efficacy of Bti is dose-dependent. There is a knowledge gap on the effects of larval exposure to sublethal Bti doses on emerging adult mosquitoes. The present study examined the effect of larval exposure to sublethal doses of Bti on the survival, body size and oviposition rate in adult Anopheles coluzzii. METHODS: Third-instar An. coluzzii larvae were exposed to control and sublethal Bti concentrations at LC20, LC50 and LC70 for 48 h. Surviving larvae were reared to adults under standard colony conditions. Thirty randomly selected females from each treatment were placed in separate cages and allowed to blood feed. Twenty-five gravid females from the blood-feeding cages were randomly selected and transferred into new cages where they were provided with oviposition cups. Numbers of eggs laid in each cage and mortality of all adult mosquitoes were recorded daily. Wing lengths were measured of 570 mosquitoes as a proxy for body size. RESULTS: Exposure to LC70Bti doses for 48 h as third-instar larvae reduced longevity of adult An. coluzzii mosquitoes. Time to death was 2.58 times shorter in females exposed to LC70Bti when compared to the control females. Estimated mortality hazard rates were also higher in females exposed to the LC50 and LC20 treatments, but these differences were not statistically significant. The females exposed to LC70 concentrations had 12% longer wings than the control group (P < 0.01). No differences in oviposition rate of the gravid females were observed between the treatments. CONCLUSIONS: Exposure of An. coluzzii larvae to sublethal Bti doses reduces longevity of resultant adults and is associated with larger adult size and unclear effect on oviposition. These findings suggest that anopheline larval exposure to sublethal Bti doses, though not recommended, could reduce vectorial capacity for malaria vector populations by increasing mortality of resultant adults.


Assuntos
Anopheles/anatomia & histologia , Bacillus thuringiensis/fisiologia , Tamanho Corporal , Longevidade , Controle de Mosquitos/métodos , Oviposição , Animais , Anopheles/fisiologia , Feminino , Larva/anatomia & histologia , Larva/fisiologia , Masculino , Mosquitos Vetores/anatomia & histologia , Mosquitos Vetores/fisiologia , Controle Biológico de Vetores
19.
Malar J ; 19(1): 5, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31906963

RESUMO

BACKGROUND: Malaria transmission is influenced by a complex interplay of factors including climate, socio-economic, environmental factors and interventions. Malaria control efforts across Africa have shown a mixed impact. Climate driven factors may play an increasing role with climate change. Efforts to strengthen routine facility-based monthly malaria data collection across Africa create an increasingly valuable data source to interpret burden trends and monitor control programme progress. A better understanding of the association with other climatic and non-climatic drivers of malaria incidence over time and space may help guide and interpret the impact of interventions. METHODS: Routine monthly paediatric outpatient clinical malaria case data were compiled from 27 districts in Malawi between 2004 and 2017, and analysed in combination with data on climatic, environmental, socio-economic and interventional factors and district level population estimates. A spatio-temporal generalized linear mixed model was fitted using Bayesian inference, in order to quantify the strength of association of the various risk factors with district-level variation in clinical malaria rates in Malawi, and visualized using maps. RESULTS: Between 2004 and 2017 reported childhood clinical malaria case rates showed a slight increase, from 50 to 53 cases per 1000 population, with considerable variation across the country between climatic zones. Climatic and environmental factors, including average monthly air temperature and rainfall anomalies, normalized difference vegetative index (NDVI) and RDT use for diagnosis showed a significant relationship with malaria incidence. Temperature in the current month and in each of the 3 months prior showed a significant relationship with the disease incidence unlike rainfall anomaly which was associated with malaria incidence at only three months prior. Estimated risk maps show relatively high risk along the lake and Shire valley regions of Malawi. CONCLUSION: The modelling approach can identify locations likely to have unusually high or low risk of malaria incidence across Malawi, and distinguishes between contributions to risk that can be explained by measured risk-factors and unexplained residual spatial variation. Also, spatial statistical methods applied to readily available routine data provides an alternative information source that can supplement survey data in policy development and implementation to direct surveillance and intervention efforts.


Assuntos
Clima , Malária/epidemiologia , Teorema de Bayes , Criança , Pré-Escolar , Mapeamento Geográfico , Humanos , Incidência , Malaui/epidemiologia , Estações do Ano , Temperatura
20.
Wellcome Open Res ; 4: 57, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31372502

RESUMO

Background: The prevalence of malaria infection in time and space provides important information on the likely sub-national epidemiology of malaria burdens and how this has changed following intervention. Model-based geostatitics (MBG) allow national malaria control programmes to leverage multiple data sources to provide predictions of malaria prevalance by district over time. These methods are used to explore the possible changes in malaria prevalance in Malawi from 2010 to 2017.  Methods: Plasmodium falciparum parasite prevalence ( PfPR) surveys undertaken in Malawi between 2000 and 2017 were assembled. A spatio-temporal geostatistical model was fitted to predict annual malaria risk for children aged 2-10 years ( PfPR 2-10) at 1×1 km spatial resolutions. Parameter estimation was carried out using the Monte Carlo maximum likelihood methods. Population-adjusted prevalence and populations at risk by district were calculated for 2010 and 2017 to inform malaria control program priority setting. Results: 2,237 surveys at 1,834 communities undertaken between 2000 and 2017 were identified, geo-coded and used within the MBG framework to predict district malaria prevalence properties for 2010 and 2017. Nationally, there was a 47.2% reduction in the mean modelled PfPR 2-10 from 29.4% (95% confidence interval (CI) 26.6 to 32.3%) in 2010 to 15.2% (95% CI 13.3 to 18.0%) in 2017. Declining prevalence was not equal across the country, 25 of 27 districts showed a significant decline ranging from a 3.3% reduction to 79% reduction. By 2017, 16% of Malawi's population still lived in areas that support PfPR 2-10 ≥ 25%. Conclusions: Malawi has made substantial progress in reducing the prevalence of malaria over the last seven years. However, Malawi remains in meso-endemic malaria transmission risk. To sustain the gains made and continue reducing the transmission further, universal control interventions need to be maintained at a national level.

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