High prevalence of IgG antibodies to Ebola virus in the Efe pygmy population in the Watsa region, Democratic Republic of the Congo

Background: Factors related to the natural transmission of Ebola virus (EBOV) to humans are still not well defined. Results of previous sero-prevalence studies suggest that circulation of EBOV in human population is common in sub-Saharan Africa. The Efe pygmies living in Democratic Republic of the Congo are known to be exposed to potential risk factors of EBOV infection such as bush meat hunting, entry into caves, and contact with bats. We studied the pygmy population of Watsa region to determine seroprevalence to EBOV infection and possible risks factors. Method: Volunteer participants (N = 300) aged 10 years or above were interviewed about behavior that may constitute risk factors for transmission of EBOV, including exposures to rats, bats, monkeys and entry into caves. Samples of venous blood were collected and tested for IgG antibody against EBOV by enzyme-linked immunosorbent assay (ELISA). The chi(2)-test and Fisher's exact test were used for the comparison of proportions and the Student's t-test to compare means. The association between age group and anti-EBOV IgG prevalence was analysed by a nonparametric test for trend. Results: The prevalence of anti-EBOV IgG was 18.7 % overall and increased significantly with age (p = 0.023). No association was observed with exposure to risk factors (contacts with rats, bats, monkeys, or entry into caves). Conclusions: The seroprevalence of IgG antibody to EBOV in pygmies in Watsa region is among the highest ever reported, but it remains unclear which exposures might lead to this high infection rate calling for further ecological and behavioural studies

High prevalence of IgG antibodies to Ebola virus in the Efé pygmy population in the Watsa region, Democratic Republic of the Congo

Background Factors related to the natural transmission of Ebola virus (EBOV) to humans are still not well defined. Results of previous sero-prevalence studies suggest that circulation of EBOV in human population is common in sub- Saharan Africa. The Efé pygmies living in Democratic Republic of the Congo are known to be exposed to potential risk factors of EBOV infection such as bush meat hunting, entry into caves, and contact with bats. We studied the pygmy population of Watsa region to determine seroprevalence to EBOV infection and possible risks factors. Method Volunteer participants (N = 300) aged 10 years or above were interviewed about behavior that may constitute risk factors for transmission of EBOV, including exposures to rats, bats, monkeys and entry into caves. Samples of venous blood were collected and tested for IgG antibody against EBOV by enzyme-linked immunosorbent assay (ELISA). The χ2-test and Fisher’s exact test were used for the comparison of proportions and the Student’s t-test to compare means. The association between age group and anti- EBOV IgG prevalence was analysed by a nonparametric test for trend. Results The prevalence of anti-EBOV IgG was 18.7 % overall and increased significantly with age (p = 0.023). No association was observed with exposure to risk factors (contacts with rats, bats, monkeys, or entry into caves). Conclusions The seroprevalence of IgG antibody to EBOV in pygmies in Watsa region is among the highest ever reported, but it remains unclear which exposures might lead to this high infection rate calling for further ecological and behavioural studies

Measles Virus Strain Diversity, Nigeria and Democratic Republic of the Congo

Differences in epidemiologic patterns are only partially explained by vaccination practices

Predictors of measles vaccination coverage among children 6-59 months of age in the Democratic Republic of the Congo.

BackgroundMeasles is a significant contributor to child mortality in the Democratic Republic of the Congo (DRC), despite routine immunization programs and supplementary immunization activities (SIA). Further, national immunization coverage levels may hide disparities among certain groups of children, making effective measles control even more challenging. This study describes measles vaccination coverage and reporting methods and identifies predictors of vaccination among children participating in the 2013-2014 DRC Demographic and Health Survey (DHS).MethodsWe examined vaccination coverage of 6947 children aged 6-59 months. A multivariate logistic regression model was used to identify predictors of vaccination among children reporting vaccination via dated card in order to identify least reached children. We also assessed spatial distribution of vaccination report type by rural versus urban residence.ResultsUrban children with educated mothers were more likely to be vaccinated (OR = 4.1, 95% CI: 1.6, 10.7) versus children of mothers with no education, as were children in wealthier rural families (OR = 2.9, 95% CI: 1.9, 4.4). At the provincial level, urban areas more frequently reported vaccination via dated card than rural areas.ConclusionsResults indicate that, while the overall coverage level of 70% is too low, socioeconomic and geographic disparities also exist which could make some children even less likely to be vaccinated. Dated records of measles vaccination must be increased, and groups of children with the greatest need should be targeted. As access to routine vaccination services is limited in DRC, identifying and targeting under-reached children should be a strategic means of increasing country-wide effective measles control

SD Bioline malaria antigen Pf (HRP-2/pLHD) for assessing efficacy of artemisinin combination therapy against Plasmodium falciparum in pediatric patients in the Democratic Republic of the Congo

Introduction: The emergence of Plasmodium falciparum resistance to artemisinin combination therapy (ACT) is a worrying development. It calls for close surveillance to monitor the efficacy of the drugs. The objectives of this study were to determine the performance of SD Bioline malaria AgPf(HRP-2/pLDH) 3  band Rapid Diagnostic Test (RDT) against Giemsa-stained blood smear and evaluate the suitability of this test in assessing the therapeutic efficacy of ACT in pediatric malaria patients in the Democratic Republic of the Congo (DRC). Methods: Five hundred and one patients with malaria symptoms were screened for P. falciparum in  Kinshasa, DRC. Of the 166 patients who tested positive for P. falciparum at recruitment (day 0), 103 consented to participate in this study and were followed up and retested for P. falciparum on day 3, day 7, day 14, day 21 and day 28. Results: Sensitivity and specificity of the test were significantly high on day 0 and so were their positive and negative predictive values. Higher proportions of false positive cases were observed on the HRP-2 band irrespective of patient parasite densities during the follow up but these were barely seen on the pLDH band. Some patients turned positive during follow up but pLDH readings remained consistent with bloodsmear readings. Conclusion: SD Bioline malaria AgPf(HRP-2/pLDH) RDT demonstrated high performance in DRC. Thus, the test can be employed to assess the efficacy of ACT in pediatric malaria patients and prioritize areas that require the deployment of advanced testing like polymerase chain reaction (PCR).Key words: Malaria, AgPf(HRP-2/pLDH) RDT, artemisinin combination therapy, Democratic Republic of the Cong

Projections of epidemic transmission and estimation of vaccination impact during an ongoing Ebola virus disease outbreak in Northeastern Democratic Republic of Congo, as of Feb. 25, 2019.

BackgroundAs of February 25, 2019, 875 cases of Ebola virus disease (EVD) were reported in North Kivu and Ituri Provinces, Democratic Republic of Congo. Since the beginning of October 2018, the outbreak has largely shifted into regions in which active armed conflict has occurred, and in which EVD cases and their contacts have been difficult for health workers to reach. We used available data on the current outbreak, with case-count time series from prior outbreaks, to project the short-term and long-term course of the outbreak.MethodsFor short- and long-term projections, we modeled Ebola virus transmission using a stochastic branching process that assumes gradually quenching transmission rates estimated from past EVD outbreaks, with outbreak trajectories conditioned on agreement with the course of the current outbreak, and with multiple levels of vaccination coverage. We used two regression models to estimate similar projection periods. Short- and long-term projections were estimated using negative binomial autoregression and Theil-Sen regression, respectively. We also used Gott's rule to estimate a baseline minimum-information projection. We then constructed an ensemble of forecasts to be compared and recorded for future evaluation against final outcomes. From August 20, 2018 to February 25, 2019, short-term model projections were validated against known case counts.ResultsDuring validation of short-term projections, from one week to four weeks, we found models consistently scored higher on shorter-term forecasts. Based on case counts as of February 25, the stochastic model projected a median case count of 933 cases by February 18 (95% prediction interval: 872-1054) and 955 cases by March 4 (95% prediction interval: 874-1105), while the auto-regression model projects median case counts of 889 (95% prediction interval: 876-933) and 898 (95% prediction interval: 877-983) cases for those dates, respectively. Projected median final counts range from 953 to 1,749. Although the outbreak is already larger than all past Ebola outbreaks other than the 2013-2016 outbreak of over 26,000 cases, our models do not project that it is likely to grow to that scale. The stochastic model estimates that vaccination coverage in this outbreak is lower than reported in its trial setting in Sierra Leone.ConclusionsOur projections are concentrated in a range up to about 300 cases beyond those already reported. While a catastrophic outbreak is not projected, it is not ruled out, and prevention and vigilance are warranted. Prospective validation of our models in real time allowed us to generate more accurate short-term forecasts, and this process may prove useful for future real-time short-term forecasting. We estimate that transmission rates are higher than would be seen under target levels of 62% coverage due to contact tracing and vaccination, and this model estimate may offer a surrogate indicator for the outbreak response challenges

Protection, health seeking, or a laissez-passer: Participants’ decision-making in an EVD vaccine trial in the eastern Democratic Republic of the Congo

During the 10th Ebola virus disease (EVD) epidemic in the eastern Democratic Republic of the Congo (DRC) (2018–2020), two experimental EVD vaccines were deployed in North Kivu. This province has been at the centre of conflict in the region for the last 25 years. Amidst ambivalence towards protracted foreign intervention and controversy about introducing two experimental vaccines, the existing literature has focused on mistrust and ‘resistance’ towards the Ebola response and vaccines. In this article, we examine why people in the eastern DRC did decide to volunteer for a trial of a second EVD vaccine in North Kivu, despite the controversy. Drawing on ethnographic observation, interviews, and focus groups with trial participants conducted between September 2020 and April 2021, we analyse three motivations for participating: protection, health seeking, and expectations surrounding travel requirements. We make three points. First, participation in vaccine trials may be understood locally to have advantages which have not been considered by the trial, because they go beyond medical considerations and are specific to a particular social setting. Second, despite much of the literature focusing on a causal relationship between rumours and ‘vaccine hesitancy’, some rumours may in fact encourage participation. Third, material objects associated with trial participation - such as participant vaccine cards - can hold social and political meaning beyond the confines of the vaccine clinic, and influence decisions surrounding participation. Empirical investigation of how medical interventions become entangled in political economies is essential to understanding the perceived functions of participation, and thus the reasons why people volunteer in clinical trials. Participants' narratives about their decision-making provide an insight into how international bioethical debates interact with, but may also stand apart from, the situated social and economic realities driving decision-making around clinical trials on the ground. This highlights the need for ethical approaches that foreground the political, social, and economic context

Indice global des signes neurologiques du konzo: marqueur clinique de multiples facteurs de susceptibilite et de gravite des troubles neurocognitifs chez l’enfant en milieu Konzo

Objectif : Quantifier la détérioration neurologique observée dans le konzo eu égard aux multiples déficiences incriminées dans sa pathogénie. Méthodes : Une étude transversale a été entreprise auprès de 123 enfants konzo et 87 non-konzo (4-17 ans) en 2011 à Kahemba, Congo-Kinshasa. L’indice global de signes neurologiques du konzo (IGSNK) était étudié en relation avec le niveau socio-économique familial évalué par le HOME, les performances cognitives au KABC-II et motrices au BOT-2, les taux sériques des isoprostanes, oligoéléments, et l’albuminémie et triglyceridémie mesurés respectivement par LC-MS/MS, ICP-MS, et automate Piccolo. Les tests de χ2, de Mann-Whitney et Kruskal-Wallis, ou la corrélation r de Spearman ont été appliqués au seuil de signification de 0,05. Résultats : L’augmentation de l’indice global des signes neurologiques du konzo était associée à la sévérité de la maladie (p < 0,001), le niveau socioéconomique familial (r = – 0,25 ; p < 0,001, la triglyceridémie (r = 0,55 , p = 0,001) et les 8,12-IsoProstaneF2-VI sériques (r = 0,33 , p= 0,06),), l’albuminémie (r = – 0,44 , p = 0,010 ) , la cuprémie ( r = – 0,36 , p= 0,048), le sélenium sérique (r = – 0,57, p = 0,001) ; en plus de l’habilité motrice globale (r = -0,861 ; p < 0,001) et l’indice global de fonctionnement cognitif (r = – 0,44 ; p = 0,002).Conclusion : L’indice global des signes neurologiques du konzo paraît être un bon marqueur clinique de multiples déficiences (pauvreté socio-familiale, malnutrition, stress oxydatif) incriminées dans la sévérité du konzo.Mots clés: malnutrition, niveau socio-économique familial, stress oxydatif, konzo, intoxication cyanhydrique, troubles moteurs et cognitifs  Konzo global neurological index: a clinical marker of susceptibility and severity of neurocognitive deficits in children living in Konzo-affected areasObjective: To quantify the extent of neurological deficits in konzo in a context of multiple factors incriminated in its pathogenesis. Methods: A cross-sectional study was carried out to assess 123 children with and 87 presumably healthy controls (4-17 years) in 2011 in kahemba, congo-kinshasa. A konzo global neurological index (KGNI) was constructed and assessed in relation to socio-economic status (assessed using the home questionnaire),  cognitive and motor performances at the KABC-II and BOT-2, respectively; serum isoprostanes (measured by LC/MS-MS), trace elements (by ICP-MS), albumin and triglycerides (by automated Piccolo). The chi-square, Mann-Whitney and Kruskal-Wallis tests as well as the Spearman r coefficients were used at the 0.05 level of statistical significance.Results: A higher KGNI was significantly associated with the severity of konzo (p < 0.001), poor socio-economic status (r = – 0.25, p < 0.001), elevated serum triglycerides (r = 0.55, p = 0.001), 8,12-isoprostane F2-VI (r = 0.33, p = 0.06), hypoalbuminemia (r = – 0.44, p = 0.010), low serum concentrations copper (r = – 0.36, p = 0.048) or selenium (r = – 0.57, p = 0.001);in addition to poor scores at the BOT-2 testing (r = -0.86; p < 0.001) and KABC-II testing for cognition (r = – 0.44; p = 0.002).Conclusion: The konzo global neurological index appears to be a good clinical marker of disease susceptibility factors (poor socio-economic status, malnutrition, oxidative stress) incriminated in the severity of konzo.Key words: malnutrition, socio-economic status, oxidative stress, cyanide intoxication, neurocognitio