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Summary: Background: Insufficient long-term data are available on antibody kinetics in survivors of Ebola virus disease (EVD). Likewise, few studies, with very small sample sizes, have investigated cross-reactions between Ebolavirus spp. In this study, we aimed to assess the humoral antibody response and its determinants in survivors of EVD and assess cross-reactivity of antibodies between diverse Ebolavirus spp. Methods: In this observational, prospective cohort study, we collected blood samples from patients from three recruitment sites in Guinea included in the Postebogui study, and we assessed IgG antibody binding to recombinant glycoprotein, nucleoprotein, and 40-kDa viral protein (VP40) of Zaire (EBOV), Bundibugyo (BDBV), and Sudan (SUDV) Ebolaviruses. Participants from the PostEbogui study, from whom we had at least one blood sample that could be tested for the presence of antibodies, were eligible for this analysis. Patients in the PostEbogui study were assessed clinically at inclusion, 1 month and 3 months later, and subsequently every 6 months for up to 60 months after discharge from the Ebola treatment centre. We explored predictors of glycoprotein, nucleoprotein, and VP40 antibody concentrations through a linear mixed model. A logistic mixed model was done to estimate the probability of seropositivity and associated determinants. We assessed cross-reactivity by use of hierarchical cluster analysis. Findings: Of the 802 patients included in the Postebogui study, 687 were included in our analyses. 310 (45%) patients were men and 377 (55%) were women, with an overall median age at the time of the first blood sample of 27·3 years (IQR 19·5–38·2). We observed an overall significant decrease over time of EBOV antibodies, with antibodies against nucleoproteins decreasing more rapidly. At 60 months after discharge from the Ebola treatment centre, the probability of having antibodies against glycoproteins was 76·2% (95% CI 67·2–83·3), against nucleoproteins was 59·4% (46·3–71·3), and against VP40 was 60·9% (51·4–69·8). Persistence of EBOV RNA in semen was associated with higher concentrations of IgG antibodies against nucleoprotein EBOV antigens. Individually, we observed in some survivors an antibody wax-and-wane pattern. The proportion of cross-reactions was highest between glycoproteins from Kissidougou and Mayinga EBOV strains (94·5%, 95% CI 92·5–96·1), followed by EBOV VP40 and BDBV VP40 (88·3%, 85·7–90·6), and EBOV VP40 and SUDV VP40 (83·3%, 80·3–86·1). Interpretation: The probability for survivors of EVD to have antibodies against one or more EBOV antigens remained high, although approximately 25% of survivors had undetectable antibodies, which could have implications, such as a possible decreasing population immunity, for future Ebola outbreaks in the same region. Funding: Reacting–Institut National de la Santé et de la Recherche Médicale, Institut de Recherche pour le Developpement, and Montpellier Université d'Excellence.

Background. Malaria control interventions have been scaled up, particularly those in pregnant women in Guinea. Despite that, coverage of key malaria preventive measure (MPM) indicators remains low. Therefore, it is vital to understand the reasons behind that, especially for the low coverage of sulfadoxine-pyrimethamine (SP) and long-lasting insecticide-treated bed nets (LLIN). Methods. We conducted a cross-sectional survey in nine district hospitals in Guinea. Pregnant women received for delivery were interviewed to collect sociodemographic and obstetrical parameters. Associated factors with MPMs were investigated through univariate analysis and classification and regression tree (CART). Results. A total of 2248 parturients participated in this study. Among pregnant women using mosquito nets (63.5% (61.4%, 65.5%)), only 41.2% (39.1%, 43.3%) had used it regularly during the last two weeks preceding delivery. Similarly, most pregnant women (57.9% (55.8%, 59.9%)) had received less than three doses of SP, and only a few pregnant women (23.9% (22.1%, 25.7%)) have benefited from full MPMs. Parturient’s age, marital status, time spent in residence, place of residence, level of education, distance from home to the health centre, health conditions, occupation, head of the household’s occupation, the presence of garbage and stagnant water in the neighbourhood, source of running water, and the number of pregnancies were significantly statistically associated with MPMs in pregnant women. However, the number of antenatal care visits (ANC), means of transportation used by the pregnant woman to accomplish ANCs, and stagnant water in the neighbourhood were the three preponderant factors. Conclusion. The low coverage of SP and LLINs among pregnant women requires revitalising some strategies, especially improving ANC coverage and more efforts to reduce inequalities in access to those services due to sociodemographic status. Education on the benefits of these MPMs should also be emphasised.

Abstract Background In 2014–2016, West Africa faced the most deadly Ebola Virus Disease (EVD) outbreak in history. A key strategy to overcome this outbreak was continual staff training in Infection Prevention and Control (IPC), with a focus on Ebola. This research aimed to evaluate the impact of IPC training and the quality of IPC performance in health care facilities of one municipality of Conakry, Guinea. Methods This study was conducted in February 2016. All health facilities within Ratoma municipality, Conakry, Guinea, were evaluated based on IPC performance standards developed by the Guinean Ministry of Health. The IPC performance of healthcare facilities was categorised into high or low IPC scores based on the median IPC score of the sample. The Mantel-Haenzsel method and logistic regression were used for statistical analysis. Results Twenty-five percent of health centres had one IPC-trained worker, 53% had at least two IPC-trained workers, and 22% of health centres had no IPC-trained workers. An IPC score above median was positively associated with the number of trained staff; health centres with two or more IPC-trained workers were eight times as likely to have an IPC score above median, while those with one IPC-trained worker were four times as likely, compared to centres with no trained workers. Health centres that implemented IPC cascade training to untrained medical staff were five times as likely to have an IPC score above median. Conclusions This research highlights the importance of training healthcare staff in IPC and organising regular cascade trainings. IPC strategies implemented during the outbreak should continue to be reinforced for the better health of patients and medical staff, and be considered a key factor in any outbreak response.