Detecting Foci of Malaria Transmission with School Surveys: A Pilot Study in the Gambia.

BACKGROUND: In areas of declining malaria transmission such as in The Gambia, the identification of malaria infected individuals becomes increasingly harder. School surveys may be used to identify foci of malaria transmission in the community. METHODS: The survey was carried out in May-June 2011, before the beginning of the malaria transmission season. Thirty two schools in the Upper River Region of The Gambia were selected with probability proportional to size; in each school approximately 100 children were randomly chosen for inclusion in the study. Each child had a finger prick blood sample collected for the determination of antimalarial antibodies by ELISA, malaria infection by microscopy and PCR, and for haemoglobin measurement. In addition, a simple questionnaire on socio-demographic variables and the use of insecticide-treated bed nets was completed. The cut-off for positivity for antimalarial antibodies was obtained using finite mixture models. The clustered nature of the data was taken into account in the analyses. RESULTS: A total of 3,277 children were included in the survey. The mean age was 10 years (SD = 2.7) [range 4-21], with males and females evenly distributed. The prevalence of malaria infection as determined by PCR was 13.6% (426/3124) [95% CI = 12.2-16.3] with marked variation between schools (range 3-25%, p<0.001), while the seroprevalence was 7.8% (234/2994) [95%CI = 6.4-9.8] for MSP119, 11.6% (364/2997) [95%CI = 9.4-14.5] for MSP2, and 20.0% (593/2973) [95% CI = 16.5-23.2) for AMA1. The prevalence of all the three antimalarial antibodies positive was 2.7% (79/2920). CONCLUSIONS: This survey shows that malaria prevalence and seroprevalence before the transmission season were highly heterogeneous

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Paediatr Int Child Health

BACKGROUND: Vertical (VT) transmission of HIV remains a public health concern in sub-Saharan Africa. OBJECTIVE: To investigate the VT rate and factors associated with transmission in routine practice in three referral hospitals in Cameroon. METHODS: All HIV-infected mothers who delivered in maternity wards or sought paediatric services during the first postnatal week from November 2007 to October 2010 were invited to participate in the ANRS-Pediacam cohort. Their infants were followed at 6, 10 and 14 weeks of life and HIV status was determined from the 6th week of life using real-time PCR. For those who were breastfed and negative at the first PCR, a second test was performed 6 weeks after breast-feeding was stopped. Logistic regression was performed to identify the independent risk factors of VT. RESULTS: Overall, 2053 HIV-exposed infants were enrolled. Of these, 1827 were tested for HIV including 1777 before the age of 3 months, and 59 were HIV-infected, resulting in an overall early VT rate of 3.3% (CI 2.5-4.3). The VT rate was significantly associated with the type of maternal exposure to ART (0.5%, 2/439, p<0.001, CI 0.0-1.6) in mothers who commenced HAART before pregnancy, 1.9% (6/321, CI 0.7-4.0) in mothers who commenced HAART during pregnancy, 4.1% (34/837, CI 2.8-5.6) in those on short-course ART and 11.1% (17/153, CI 6.6-17.2) in mothers not receiving ART. On multivariate analysis, the type of exposure to ART remained significantly associated with being small for gestational age (aOR 5.0, CI 2.4-10.3, p < 0.001) and female gender (aOR 2.1, CI 1.2-3.8, p = 0.01). CONCLUSION: The successfully low rate of VT transmission of HIV in mothers who commenced HAART in early pregnancy strongly supports the need to improve access to diagnosis and early treatment of all women of childbearing age with HIV through the national PMTCT programme. ABBREVIATIONS: ANRS: French National Agency for Research on AIDS and Viral Hepatitis; ART: antiretroviral therapy; ARV: antiretroviral; AUDIPOG: Association des Utilisateurs de Dossiers Informatises en Pediatrie, Obstetrique et Gynecologie; CHM/MCC-CBF: The Central Hospital Maternity/Mother and Child Centre of the Chantal Biya Foundation; EHC: Essos Hospital Centre; EPI: Expanded Programme on Immunization; HAART: highly active antiretroviral therapy; HBV: hepatitis B virus; IQR: interquartile range; LH: Laquintinie Hospital; MTCT: mother-to-child transmission; NVP: nevirapine; Pediacam: Pediatrie Cameroun; PMTCT: prevention of mother-to-child transmission; SGAG: small for gestational age and gender; UNAIDS: Joint United Nations Program on HIV/AIDS; WHO: World Health Organization; ZDV: zidovudine; 3TC: lamivudine

Rev Epidemiol Sante Publique

Position du problème Au Cameroun, la couverture des enfants éligibles au traitement antirétroviral (TARV) (15 %) était l’une des plus faibles des 21 pays prioritaires du Fonds Mondial en 2012. Le but de cette étude était de faire une analyse situationnelle de l’offre des soins pour améliorer la prise en charge du VIH pédiatrique (PECP) au Cameroun. Méthodes Une étude transversale descriptive a été menée pendant quatre mois (avril à août 2014) dans 12 formations sanitaires de sept régions du Cameroun sélectionnées par un sondage systématique. Les données ont été recueillies à l’aide d’un auto-questionnaire administré aux personnels soignants et aux responsables administratifs inclus dans l’étude. Résultats Au total 142 personnels en charge du VIH pédiatrique ont été inclus dans cette étude : 115 du niveau opérationnel parmi lesquels 59 (51,2 %) personnels de santé, 44 (38,3 %) agents communautaires, 12 (10,4 %) chefs de services, 19 responsables du niveau régional et 8 du niveau central. La grande majorité des personnels soignants impliqués dans la PECP étaient des infirmiers, nécessitant ainsi la délégation effective des tâches médicales institutionnalisée au Cameroun. Très peu de documents normatifs nationaux prenaient en compte la PECP. La faible vulgarisation de ces documents normatifs à tous les niveaux de la pyramide sanitaire pourrait justifier le non-respect des protocoles de prise en charge observé dans les formations sanitaires offrant la PECP. Conclusion La mise à jour et la diffusion à large échelle des documents nationaux normatifs, prenant en compte des spécificités de l’enfant infecté par le VIH, sont nécessaires pour améliorer l’application des directives de la PECP au niveau opérationnel.Background In Cameroon in 2012, the proportion (15%) of children eligible for antiretroviral treatment (ART) was one of the lowest among the 21 Global Fund priority countries. The objective of this study was to carry out a situational analysis of the existing care offer for pediatric HIV in Cameroon. Methods A descriptive cross-sectional study was conducted over a 4-month period (April to August 2014) in 12 healthcare facilities in 7 regions of Cameroon selected by systematic sampling. The data were collected in a self-administered questionnaire filled out by the caregiving and administrative personnel included in the study. Results All in all, 142 persons in charge of pediatric HIV treatment were included in the study, of whom 115 were working at the operational level: 59 (51.2%) health personnel, 44 (38.3%) community agents and 12 (10.4%) department heads; the other 27 exercised responsibilities at the regional (19) and the local (8) levels. An overwhelming majority of the caregivers involved in pediatric VIH treatment were nurses, a factor necessitating the delegation of medical tasks institutionalized in Cameroon. Few standardized nationwide documents take into account these treatment modalities. Inadequate dissemination of the documents at all levels of the healthcare pyramid may justify the non-compliance with the care protocols that has been observed in the training programs dedicated to the subject. Conclusion The updating and large-scale dissemination of standardized nationwide documents taking into account the specificities of HIV-infected children are required to improve implementation at the operational level of the Cameroonian healthcare system of the existing guidelines for pediatric HIV treatment

Individual and healthcare supply-related barriers to treatment initiation in HIV-positive patients enrolled in the Cameroonian antiretroviral treatment access programme

International audienceIncreasing demand for antiretroviral treatment (ART) together with a reduction in international funding during the last decade may jeopardize access to ART. Using data from a cross-sectional survey conducted in 2014 in 19 HIV services in the Centre and Littoral regions in Cameroon, we investigated the role of healthcare supply-related factors in time to ART initiation in HIV-positive patients eligible for ART at HIV diagnosis. HIV service profiles were built using cluster analysis. Factors associated with time to ART initiation were identified using a multilevel Cox model. The study population included 847 HIV-positive patients (women 72%, median age: 39 years). Median (interquartile range) time to ART initiation was 1.6 (0.5-4.3) months. Four HIV service profiles were identified: (1) small services with a limited staff practising partial task-shifting (n = 4); (2) experienced and well-equipped services practising task-shifting and involving HIV community-based organizations (n = 5); (3) small services with limited resources and activities (n = 6); (4) small services providing a large range of activities using task-shifting and involving HIV community-based organizations (n = 4). The multivariable model showed that HIV-positive patients over 39 years old [hazard ratio: 1.26 (95% confidence interval) (1.09-1.45), P = 0.002], those with disease symptoms [1.21 (1.04-1.41), P = 0.015] and those with hepatitis B co-infection [2.31 (1.15-4.66), P = 0.019] were all more likely to initiate ART early. However, patients in the first profile were less likely to initiate ART early [0.80 (0.65-0.99), P = 0.049] than those in the second profile, as were patients in the third profile [association only significant at the 10% level; 0.86 (0.72-1.02), P = 0.090]. Our findings provide a better understanding of the role played by healthcare supply-related factors in ART initiation. In HIV services with limited capacity, task-shifting and support from community-based organizations may improve treatment access. Additional funding is required to relieve healthcare supply-related barriers and achieve the goal of universal ART access