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Abstract Introduction Serological surveys offer the most direct measurement to define the immunity status for numerous infectious diseases, such as COVID-19, and can provide valuable insights into understanding transmission patterns. This study describes seroprevalence changes over time in the context of the Democratic Republic of Congo, where COVID-19 case presentation was apparently largely oligo- or asymptomatic, and vaccination coverage remained extremely low. Methods A cohort of 635 health care workers (HCW) from 5 health zones of Kinshasa and 670 of their household members was interviewed and sampled in 6 rounds between July 2020 and January 2022. At each round, information on risk exposure and a blood sample were collected. Serology was defined as positive when binding antibodies against SARS-CoV-2 spike and nucleocapsid proteins were simultaneously present. Results The SARS-CoV-2 antibody seroprevalence was high at baseline, 17.3% (95% CI 14.4–20.6) and 7.8% (95% CI 5.5–10.8) for HCW and household members, respectively, and fluctuated over time, between 9% and 62.1%. Seropositivity was heterogeneously distributed over the health zones (p

In September 2022, deaths of pigs manifesting pox-like lesions caused by swinepox virus were reported in Tshuapa Province, Democratic Republic of the Congo. Two human mpox cases were found concurrently in the surrounding community. Specific diagnostics and robust sequencing are needed to characterize multiple poxviruses and prevent potential poxvirus transmission.

ABSTRACT The growing resistance to amoxicillin (AMX)—one of the main antibiotics used in Helicobacter pylori eradication therapy—is an increasing health concern. Several mutations of penicillin-binding protein 1A (PBP1A) are suspected of causing AMX resistance; however, only a limited set of these mutations have been experimentally explored. This study aimed to investigate four PBP1A mutations (i.e., T558S, N562H, T593A, and G595S) carried by strain KIN76, a high-level AMX-resistant clinical H. pylori isolate with an AMX minimal inhibition concentration (MIC) of 2 µg/mL. We transformed a recipient strain 26695 with the DNA containing one to four mutation allele combinations of the pbp1 gene from strain KIN76. Transformants were subjected to genomic exploration and antimicrobial susceptibility testing. The resistance was transformable, and the presence of two to four PBP1A mutations (T558S and N562H, or T593A and G595S), rather than separate single mutations, was necessary to synergistically increase the AMX MIC up to 16-fold compared with the wild-type (WT) strain 26695. An AMX binding assay of PBP1A was performed using these strains, and binding was visualized by chasing Bocillin, a fluorescent penicillin analog. This revealed that all four-mutation allele-transformed strains exhibited decreased affinity to AMX on PBP1A than the WT. Protein structure modeling indicated that functional modifications occur as a result of these amino acid substitutions. This study highlights a new synergistic AMX resistance mechanism and establishes new markers of AMX resistance in H. pylori.IMPORTANCEThe development of resistance to antibiotics, including amoxicillin, is hampering the eradication of Helicobacter pylori infection. The identification of mechanisms driving this resistance is crucial for the development of new therapeutic strategies. We have demonstrated in vitro the synergistic role of novel mutations in the pbp1 gene of H. pylori that is suspected to drive amoxicillin resistance. Also deepening our understanding of amoxicillin resistance mechanisms, this study establishes new molecular markers of amoxicillin resistance that may be useful in molecular-based antibiotic susceptibility testing approaches for clinical practice or epidemiologic investigations.

Summary: Background: Ebola virus disease (EVD) is associated with multisystem organ failure and high mortality. Severe hypoglycaemia is common, life-threatening, and correctable in critically ill patients, but glucose monitoring may be limited in EVD treatment units. Methods: We conducted a retrospective review of patients admitted to EVD treatment units in Butembo and Katwa, Eastern DRC. Glucose measurements were done using a handheld glucometer at the bedside or using the Piccolo xpress Chemistry Analyzer on venous samples. Findings: 384 patients (median age 30 years (interquartile range, IQR, 20–45), 57% female) and 6422 glucose measurements (median 11 per patient, IQR 4–22) were included in the analysis. Severe hypoglycaemia (≤2.2 mmol/L) and hyperglycaemia (>10 mmol/L) were recorded at least once during the ETU admission in 97 (25%) and 225 (59%) patients, respectively. A total of 2004 infusions of glucose-containing intravenous solutions were administered to 302 patients (79%) with a median cumulative dose of 175g (IQR 100–411). The overall case fatality rate was 157/384 (41%) and was 2.2-fold higher (95% CI 1.3–3.8) in patients with severe hypoglycaemia than those without hypoglycaemia (p = 0.0042). In a multivariable Cox proportional hazards model, periods of severe hypoglycaemia (adjusted hazard ratio (aHR) 6.2, 95% CI 3.2–12, p

Odontogenic bone tumor (OT) is a rare pathology in the world, but it is very common in developing countries; its etiology is still unknown, and it causes serious deformities of the mandible and maxilla if it is not operated upon soon. Lassa virus (LASV) belongs to the Arenaviridae family, and its reservoir is a rodent of the genus Mastomys. The transmission of the LASV to humans can occur through ingestion or inhalation by contact with dirty objects, the consumption of contaminated food, or exposure to wounds, as rodents shed the virus in their urine and excrement. In this observational study, we aim to evaluate the presence of LASV in OT patient tissues collected in the Democratic Republic of the Congo. For this purpose, a group of nine patients affected by OT were enrolled, and the tissues derived from the surgery were collected. In total, 81.5% of the tissues were positive for LASV presence. Interestingly, we found that not only was the tumor LASV-positive, but in some cases, the bone was close to the tumor and the oral mucosa lining. These preliminary data could suggest the hypothesis that LASV may be involved with the onset of OT.

We report a cluster of clade I monkeypox virus infections linked to sexual contact in the Democratic Republic of the Congo. Case investigations resulted in 5 reverse transcription PCR–confirmed infections; genome sequencing suggest they belonged to the same transmission chain. This finding demonstrates that mpox transmission through sexual contact extends beyond clade IIb.

BackgroundSeveral governments from African countries, including the Democratic Republic of the Congo (DRC), implemented stringent public health measures to curb COVID-19 transmission in the early phases of the pandemic. While these restrictive measures are believed to have contributed to lowering case incidence and related mortality in DRC, data on the population’s knowledge and adherence are limited. This study aimed to assess the knowledge, perception, attitudes, and practices of COVID-19 preventive measures and associated factors among adult residents of Matadi, thereby generating evidence for a strategy adjustment as the COVID-19 response is transitioning from emergency to control status.MethodsWe used data from a population-based cross-sectional study conducted in October 2021. Consenting participants were enrolled through a multi-stage cluster sampling approach and administered a pre-tested structured questionnaire using a mobile application (Epicollect 5). We analyzed adult participants’ data using STATA 15.1. Univariable and multivariable analyses were applied to identify factors associated with good knowledge, good perception, positive attitude and good practice.ResultsWe included 1,269 adult respondents for the secondary analysis. One respondent in six was female. The median age was 36 years (IQR 24–50). Most respondents (76.5%) had good knowledge. Respondents aged 40–49 years and those with vocational education level were 1.7 time (AOR 1.75, 95% CI 1.07–2.87) and twice as likely (AOR 2.06, 95% CI 1.01–4.21) to have good knowledge. Preventive measures were perceived as efficient by 45% of respondents. Good perception was associated with education level, profession, average household monthly income and good knowledge. Only 40% of respondents had a positive attitude. A positive attitude was associated with age, education level, and good knowledge. Respondents having good practice represented 5.8%. Good practice was associated with good knowledge, attitude and perception.ConclusionMost respondents were knowledgeable, had a good perception of government-related COVID-19 preventive measures, a moderately positive attitude and an extremely low level of good practice. Current COVID-19 preventive strategies, including vaccination rollout, need adjustment into high-efficiency, context-based and risk group-specific interventions. Evidence generated by this study will improve preparedness and response to future outbreaks.

IntroductionNon-communicable diseases (NCDs), the leading cause of death globally, are estimated to overtake communicable diseases in sub-Sahara Africa, where healthcare workers (HCWs) play a crucial role in prevention and treatment, but are in extreme shortage, thereby increasing the burden of NCDs among this specific population. To provide evidence for policy-making, we assessed the NCD burden, associated factors and treatment among HCWs in four sub-Saharan African countries.Materials and methodsWe conducted a cross-sectional study across four sub-Saharan African countries [Côte d'Ivoire (CIV), Democratic Republic of the Congo (DRC), Madagascar (MDG), and Nigeria (NIG)] between February and December 2022. In a standardized questionnaire, sociodemographic, chronic disease and treatment data were self-reported. We estimated the prevalence of (1) at least one chronic disease, (2) hypertension, and used backward elimination logistic regression model to identify risk factors.ResultsWe recruited a total of 6,848 HCWs. The prevalence of at least one chronic disease ranged between 9.7% in NIG and 20.6% in MDG, the prevalence of hypertension between 5.4% in CIV and 11.3% in MDG. At most, reported treatment rates reached 36.5%. The odds of each of both outcomes increased with age (at least one chronic disease adjusted odds ratio: CIV: 1.04; DRC: 1.09; MDG: 1.06; NIG: 1.10; hypertension: CIV: 1.10; DRC: 1.31; MDG: 1.11; NIG: 1.11) and with BMI (at least one chronic disease: CIV: 1.10; DRC: 1.07; MDG: 1.06; NIG: 1.08; hypertension: CIV: 1.10; DRC: 1.66; MDG: 1.13; NIG: 1.07). Odds of both outcomes were lower among males, except in CIV. In NIG, the odds of both outcomes were higher among medical doctors and odds of hypertension were higher among those working in secondary care. In MDG, working in secondary care increased and working as auxiliary staff decreased the odds of at least one chronic disease.ConclusionThe prevalence of self-reported chronic disease varied across the four sub-Saharan countries with potentially very low treatment rates. We identified several individual (age, sex, and BMI) and occupational (profession, level of healthcare) factors that influence the odds of NCDs. These factors should be taken into account when developing interventions addressing the burden and management of NCDs among HCWs.

Background and Objectives. The chest computed tomography (chest CT) has played an important role in the management of COVID-19. Few data on its use in sub-Saharan Africa (SSA) are reported. The objectives of this study conducted in Kinshasa, DR Congo, were to describe the lung lesions on day 1 of hospitalization in patients admitted for suspected COVID-19 and to identify those that were most associated with SARS-CoV-2 infection/RT-PCR and the determinants of chest CT associated with death. Methods. We included all patients with respiratory symptoms (dyspnea, fever, and cough) and/or respiratory failure admitted to the SOS Médecins de nuit SARL hospital, DR Congo, during the 2nd and 3rd waves of the COVID-19 pandemic. The diagnosis of COVID-19 was established based on RT-PCR anti-SARS-CoV-2 tests (G1 (RT-PCR positive) vs. G2 (RT-PCR negative)), and all patients had a chest CT on the day of admission. We retrieved the digital files of patients, precisely the clinical, biological, and chest CT parameters of the day of admission as well as the vital outcome (survival or death). Chest CT were read by a very high-definition console using Advantage Windows software and exported to the hospital network using the RadiAnt DICOM viewer. To determine the threshold for the percentage of lung lesions associated with all-cause mortality, we used ROC curves. Factors associated with death, including chest CT parameters, were investigated using logistic regression analysis. Results. The study included 200 patients (average age 56.2±15.2 years; 19% diabetics and 4.5% obese), and COVID-19 was confirmed among 56% of them (G1). Chest CT showed that ground glass (72.3 vs. 39.8%), crazy paving (69.6 vs. 17.0%), and consolidation (83.9 vs. 22.7%), with bilateral and peripheral locations (68.8 vs. 30.7%), were more frequent in G1 vs. G2 (p

Objectives: The origin and spread of dengue virus (DENV) circulating in Africa remain poorly characterized, with African sequences representing

The 10th Ebola virus disease (EVD) outbreak in the Democratic Republic of the Congo (DRC) drew substantial attention from the international community, which in turn invested more than US$1 billion in EVD control over two years (2018–2020). This is the first EVD outbreak to take place in a conflict area, which led to a shift in strategy from a pure public health response (PHR) to a multisectoral humanitarian response. A wide range of disease control and mitigation activities were implemented and were outlined in the five budgeted Strategic Response Plans used throughout the 26 months. This study used the budget/expenditure and output indicators for disease control and mitigation interventions compiled by the government of DRC and development and humanitarian partners to estimate unit costs of key Ebola control interventions. Of all the investment in EVD control, 68% was spent on PHR. The remaining 32% covered security, community support interventions for the PHR. The disbursement for the public health pillar was distributed as follows: (1) coordination (18.8%), (2), clinical management of EVD cases (18.4%), (3) surveillance and vaccination (15.9%), (4) infection prevention and control/WASH (13.8%) and (5) risk communication (13.7%). The unit costs of key EVD control interventions were as follows: US$66 182 for maintaining a rapid response team per month, US$4435 for contact tracing and surveillance per identified EVD case, US$1464 for EVD treatment per case, US$59.4 per EVD laboratory test, US$120.7 per vaccinated individual against EVD and US$175.0 for mental health and psychosocial support per beneficiary. The estimated unit costs of key EVD disease control interventions provide crucial information for future infectious disease control planning and budgeting, as well as prioritisation of disease control interventions.

During the 10th outbreak of Ebola virus disease in the Democratic Republic of the Congo, the Institut National de Recherche Biomédicale strategically positioned 13 decentralized field laboratories with dedicated equipment to quickly detect cases as the outbreak evolved. The laboratories were operated by national staff, who quickly handed over competencies and skills to local persons to successfully manage future outbreaks. Laboratories analyzed ≈230,000 Ebola diagnostic samples under stringent biosafety measures, documentation, and database management. Field laboratories diversified their activities (diagnosis, chemistry and hematology, survivor follow-up, and genomic sequencing) and shipped 127,993 samples from the field to a biorepository in Kinshasa under good conditions. Deploying decentralized and well-equipped laboratories run by local personnel in at-risk countries for Ebola virus disease outbreaks is an efficient response; all activities are quickly conducted in the field.

Serologic surveys are important tools for estimating the true burden of COVID-19 in a given population. After the first wave of SARS-CoV-2 infections, a household-based survey conducted in Kinshasa, Democratic Republic of the Congo, estimated >292 infections going undiagnosed for every laboratory-confirmed case. To ascertain the cumulative population exposure in Kinshasa after the second wave of COVID-19, we conducted a prospective population-based cross-sectional study using a highly sensitive and specific ELISA kit. The survey included 2,560 consenting persons from 585 households; 55% were female and 45% male. The overall population-weighted, test kit–adjusted SARS-CoV-2 seroprevalence was 76.5% (95% CI 74.5%–78.5%). The seroprevalence was 4-fold higher than during the first wave, and positivity was associated with age, household average monthly income, and level of education. Evidence generated from this population-based survey can inform COVID-19 response, especially vaccination campaign strategies in the context of vaccine shortages and hesitancy.

Polio-associated paralysis is one of the diseases under national surveillance in the Democratic Republic of the Congo (DRC). Although it has become relatively rare due to control measures, non-polio paralysis cases are still reported and constitute a real problem, especially for etiological diagnosis, which is necessary for better management and response. From September 2022 to April 2023, we investigated acute flaccid paralysis (AFP) cases in Kinshasa following an alert from the Provincial Division of Health. All suspected cases and their close contacts were investigated and sampled. Among the 57 sampled patients, 21 (36.8%) were suspects, and 36 (63.2%) were contacts. We performed several etiological tests available in the laboratory, targeting viruses, including Poliovirus, Influenza virus, SARS-CoV-2, Enterovirus, and arboviruses. No virus material was detected, but the serological test (ELISA) detected antibodies against Chikungunya Virus, i.e., 47.4% (27/57) for IgM and 22.8% (13/57) for IgG. Among suspected cases, we detected 33.3% (7/21) with anti-Chikungunya IgM and 14.3% (3/21) of anti-Chikungunya IgG. These results highlight the importance of enhancing the epidemiological surveillance of Chikungunya.

Introduction Despite tremendous progress in the development of diagnostics, vaccines and therapeutics for Ebola virus disease (EVD), challenges remain in the implementation of holistic strategies to rapidly curtail outbreaks. We investigated the effectiveness of a community-based contact isolation strategy to limit the spread of the disease in the Democratic Republic of Congo (DRC).Methods We did a quasi-experimental comparison study. Eligible participants were EVD contacts registered from 12 June 2019 to 18 May 2020 in Beni and Mabalako Health Zones. Intervention group participants were isolated to specific community sites for the duration of their follow-up. Comparison group participants underwent contact tracing without isolation. The primary outcome was measured as the reproduction number (R) in the two groups. Secondary outcomes were the delay from symptom onset to isolation and case management, case fatality rate (CFR) and vaccination uptake.Results 27 324 EVD contacts were included in the study; 585 in the intervention group and 26 739 in the comparison group. The intervention group generated 32 confirmed cases (5.5%) in the first generation, while the comparison group generated 87 (0.3%). However, the 32 confirmed cases arising from the intervention contacts did not generate any additional transmission (R=0.00), whereas the 87 confirmed cases arising from the comparison group generated 99 secondary cases (R=1.14). The average delay between symptom onset and case isolation was shorter (1.3 vs 4.8 days; p

Summary: Background: Ebola virus disease (EVD) outbreaks have emerged in Central and West Africa. EVD diagnosis relies principally on RT-PCR testing with GeneXpert®, which has logistical and cost restrictions at the peripheral level of the health system. Rapid diagnostic tests (RDTs) would offer a valuable alternative at the point-of-care to reduce the turn-around time, if they show good performance characteristics. We evaluated the performance of four EVD RDTs against the reference standard GeneXpert® on stored EVD positive and negative blood samples collected between 2018 and 2021 from outbreaks in eastern Democratic Republic of the Congo (DRC). Methods: We conducted a prospective and observational study in the laboratory on QuickNavi-Ebola™, OraQuick® Ebola Rapid Antigen, Coris® EBOLA Ag K-SeT, and Standard® Q Ebola Zaïre Ag RDTs using left-over archived frozen EDTA whole blood samples. We randomly selected 450 positive and 450 negative samples from the EVD biorepositories in DRC, across a range of GeneXpert® cycle threshold values (Ct-values). RDT results were read by three persons and we considered an RDT result as “positive”, when it was flagged as positive by at least two out of the three readers. We estimated the sensitivity and specificity through two independent generalized (logistic) linear mixed models (GLMM). Findings: 476 (53%) of 900 samples had a positive GeneXpert Ebola result when retested. The QuickNavi-Ebola™ showed a sensitivity of 56.8% (95% CI 53.6–60.0) and a specificity of 97.5% (95% CI 96.2–98.4), the OraQuick® Ebola Rapid Antigen test displayed 61.6% (95% CI 57.0–65.9) sensitivity and 98.1% (95% CI 96.2–99.1) specificity, the Coris® EBOLA Ag K-SeT showed 25.0% (95% CI 22.3–27.9) sensitivity and 95.9% (95% CI 94.2–97.1) specificity, and the Standard® Q Ebola Zaïre Ag displayed 21.6% (95% CI 18.1–25.7) sensitivity and 99.1% (95% CI 97.4–99.7) specificity. Interpretation: None of the RDTs evaluated approached the ''desired or acceptable levels'' for sensitivity set out in the WHO target product profile, while all of the tests met the ''desired level'' for specificity. Nevertheless, the QuickNavi-Ebola™ and OraQuick® Ebola Rapid Antigen Test demonstrated the most favorable profiles, and may be used as frontline tests for triage of suspected-cases while waiting for RT-qPCR confirmatory testing. Funding: Institute of Tropical Medicine Antwerp/EDCTP PEAU-EBOV-RDC project.

Abstract Background Loss of efficacy of diagnostic tests may lead to untreated or mistreated malaria cases, compromising case management and control. There is an increasing reliance on rapid diagnostic tests (RDTs) for malaria diagnosis, with the most widely used of these targeting the Plasmodium falciparum histidine-rich protein 2 (PfHRP2). There are numerous reports of the deletion of this gene in P. falciparum parasites in some populations, rendering them undetectable by PfHRP2 RDTs. The aim of this study was to identify P. falciparum parasites lacking the P. falciparum histidine rich protein 2 and 3 genes (pfhrp2/3) isolated from asymptomatic and symptomatic school-age children in Kinshasa, Democratic Republic of Congo. Methods The performance of PfHRP2-based RDTs in comparison to microscopy and PCR was assessed using blood samples collected and spotted on Whatman 903™ filter papers between October and November 2019 from school-age children aged 6–14 years. PCR was then used to identify parasite isolates lacking pfhrp2/3 genes. Results Among asymptomatic malaria carriers (N = 266), 49%, 65%, and 70% were microscopy, PfHRP2_RDT, and pfldh-qPCR positive, respectively. The sensitivity and specificity of RDTs compared to PCR were 80% and 70% while the sensitivity and specificity of RDTs compared to microscopy were 92% and 60%, respectively. Among symptomatic malaria carriers (N = 196), 62%, 67%, and 87% were microscopy, PfHRP2-based RDT, pfldh-qPCR and positive, respectively. The sensitivity and specificity of RDTs compared to PCR were 75% and 88%, whereas the sensitivity and specificity of RDTs compared to microscopy were 93% and 77%, respectively. Of 173 samples with sufficient DNA for PCR amplification of pfhrp2/3, deletions of pfhrp2 and pfhrp3 were identified in 2% and 1%, respectively. Three (4%) of samples harboured deletions of the pfhrp2 gene in asymptomatic parasite carriers and one (1%) isolate lacked the pfhrp3 gene among symptomatic parasite carriers in the RDT positive subgroup. No parasites lacking the pfhrp2/3 genes were found in the RDT negative subgroup. Conclusion Plasmodium falciparum histidine-rich protein 2/3 gene deletions are uncommon in the surveyed population, and do not result in diagnostic failure. The use of rigorous PCR methods to identify pfhrp2/3 gene deletions is encouraged in order to minimize the overestimation of their prevalence.

BackgroundNo distinctive clinical signs of Ebola virus disease (EVD) have prompted the development of rapid screening tools or called for a new approach to screening suspected Ebola cases. New screening approaches require evidence of clinical benefit and economic efficiency. As of now, no evidence or defined algorithm exists.ObjectiveTo evaluate, from a healthcare perspective, the efficiency of incorporating Ebola prediction scores and rapid diagnostic tests into the EVD screening algorithm during an outbreak.MethodsWe collected data on rapid diagnostic tests (RDTs) and prediction scores' accuracy measurements, e.g., sensitivity and specificity, and the cost of case management and RDT screening in EVD suspect cases. The overall cost of healthcare services (PPE, procedure time, and standard-of-care (SOC) costs) per suspected patient and diagnostic confirmation of EVD were calculated. We also collected the EVD prevalence among suspects from the literature. We created an analytical decision model to assess the efficiency of eight screening strategies: 1) Screening suspect cases with the WHO case definition for Ebola suspects, 2) Screening suspect cases with the ECPS at -3 points of cut-off, 3) Screening suspect cases with the ECPS as a joint test, 4) Screening suspect cases with the ECPS as a conditional test, 5) Screening suspect cases with the WHO case definition, then QuickNavi™-Ebola RDT, 6) Screening suspect cases with the ECPS at -3 points of cut-off and QuickNavi™-Ebola RDT, 7) Screening suspect cases with the ECPS as a conditional test and QuickNavi™-Ebola RDT, and 8) Screening suspect cases with the ECPS as a joint test and QuickNavi™-Ebola RDT. We performed a cost-effectiveness analysis to identify an algorithm that minimizes the cost per patient correctly classified. We performed a one-way and probabilistic sensitivity analysis to test the robustness of our findings.ResultsOur analysis found dual ECPS as a conditional test with the QuickNavi™-Ebola RDT algorithm to be the most cost-effective screening algorithm for EVD, with an effectiveness of 0.86. The cost-effectiveness ratio was 106.7 USD per patient correctly classified. The following algorithms, the ECPS as a conditional test with an effectiveness of 0.80 and an efficiency of 111.5 USD per patient correctly classified and the ECPS as a joint test with the QuickNavi™-Ebola RDT algorithm with an effectiveness of 0.81 and a cost-effectiveness ratio of 131.5 USD per patient correctly classified. These findings were sensitive to variations in the prevalence of EVD in suspected population and the sensitivity of the QuickNavi™-Ebola RDT.ConclusionsFindings from this study showed that prediction scores and RDT could improve Ebola screening. The use of the ECPS as a conditional test algorithm and the dual ECPS as a conditional test and then the QuickNavi™-Ebola RDT algorithm are the best screening choices because they are more efficient and lower the number of confirmation tests and overall care costs during an EBOV epidemic.

Introduction A serosurvey among health care providers (HCPs) and frontliners of an area previously affected by Ebola virus disease (EVD) in the Democratic Republic of the Congo (DRC) was conducted to assess the seroreactivity to Ebola virus antigens. Methods Serum samples were collected in a cohort of HCPs and frontliners (n = 698) participants in the EBL2007 vaccine trial (December 2019 to October 2022). Specimens seroreactive for EBOV were confirmed using either the Filovirus Animal Nonclinical Group (FANG) ELISA or a Luminex multiplex assay. Results The seroreactivity to at least two EBOV-Mayinga (m) antigens was found in 10 (1.4%: 95% CI, 0.7–2.6) samples for GP-EBOV-m + VP40-EBOV-m, and 2 (0.3%: 95% CI, 0.0–1.0) samples for VP40-EBOV-m + NP-EBOV-m using the Luminex assay. Seroreactivity to GP-EBOV-Kikwit (k) was observed in 59 (8.5%: 95%CI, 6.5–10.9) samples using FANG ELISA. Conclusion In contrast to previous serosurveys, a low seroprevalence was found in the HCP and frontline population participating in the EBL2007 Ebola vaccine trial in Boende, DRC. This underscores the high need for standardized antibody assays and cutoffs in EBOV serosurveys to avoid the broad range of reported EBOV seroprevalence rates in EBOV endemic areas.

A community-based coronavirus disease (COVID-19) active case-finding strategy using an antigen-detecting rapid diagnostic test (Ag-RDT) was implemented in the Democratic Republic of Congo (DRC) to enhance COVID-19 case detection. With this pilot community-based active case finding and response program that was designed as a clinical, prospective testing performance, and implementation study, we aimed to identify insights to improve community diagnosis and rapid response to COVID-19. This pilot study was modeled on the DRC's National COVID-19 Response Plan and the COVID-19 Ag-RDT screening algorithm defined by the World Health Organization (WHO), with case findings implemented in 259 health areas, 39 health zones, and 9 provinces. In each health area, a 7-member interdisciplinary field team tested the close contacts (ring strategy) and applied preventive and control measures to each confirmed case. The COVID-19 testing capacity increased from 0.3 tests per 10,000 inhabitants per week in the first wave to 0.4, 1.6, and 2.2 in the second, third, and fourth waves, respectively. From January to November 2021, this capacity increase contributed to an average of 10.5% of COVID-19 tests in the DRC, with 7,110 positive Ag-RDT results for 40,226 suspected cases and close contacts who were tested (53.6% female, median age: 37 years [interquartile range: 26.0-50.0)]. Overall, 79.7% (n = 32,071) of the participants were symptomatic and 7.6% (n = 3,073) had comorbidities. The Ag-RDT sensitivity and specificity were 55.5% and 99.0%, respectively, based on reverse transcription polymerase chain reaction analysis, and there was substantial agreement between the tests (k = 0.63). Despite its limited sensitivity, the Ag-RDT has improved COVID-19 testing capacity, enabling earlier detection, isolation, and treatment of COVID-19 cases. Our findings support the community testing of suspected cases and asymptomatic close contacts of confirmed cases to reduce disease spread and virus transmission.

After a pilot study, we tested 443 cadavers using OraQuick Ebola rapid diagnostic tests during surveillance after the 10th Ebola outbreak in the Democratic Republic of the Congo. No false negative and 2% false-positive results were reported. Quickly returning results and engaging the community enabled timely public health actions.

The seroprevalence to orthoebolaviruses was studied in 9594 bats (5972 frugivorous and 3622 insectivorous) from Cameroon, the Democratic Republic of Congo (DRC) and Guinea, with a Luminex-based serological assay including recombinant antigens of four orthoebolavirus species. Seroprevalence is expressed as a range according to different cut-off calculations. Between 6.1% and 18.9% bat samples reacted with at least one orthoebolavirus antigen; the highest reactivity was seen with Glycoprotein (GP) antigens. Seroprevalence varied per species and was higher in frugivorous than insectivorous bats; 9.1–27.5% versus 1.3–4.6%, respectively. Seroprevalence in male (13.5%) and female (14.4%) bats was only slightly different and was higher in adults (14.9%) versus juveniles (9.4%) (p < 0.001). Moreover, seroprevalence was highest in subadults (45.4%) when compared to mature adults (19.2%), (p < 0.001). Our data suggest orthoebolavirus circulation is highest in young bats. More long-term studies are needed to identify birthing pulses for the different bat species in diverse geographic regions and to increase the chances of detecting viral RNA in order to document the genetic diversity of filoviruses in bats and their pathogenic potential for humans. Frugivorous bats seem more likely to be reservoirs of orthoebolaviruses, but the role of insectivorous bats has also to be further examined.

Human Mpox cases are increasingly reported in Africa, with the highest burden in the Democratic Republic of Congo (DRC). While case reporting on a clinical basis can overestimate infection rates, laboratory confirmation by PCR can underestimate them, especially on suboptimal samples like blood, commonly used in DRC. Here we used a Luminex-based assay to evaluate whether antibody testing can be complementary to confirm cases and to identify human transmission chains during outbreak investigations. We used left-over blood samples from 463 patients, collected during 174 outbreaks between 2013 and 2022, with corresponding Mpox and VZV PCR results. In total, 157 (33.9%) samples were orthopox-PCR positive and classified as Mpox+; 124 (26.8%) had antibodies to at least one of the three Mpox peptides. The proportion of antibody positive samples was significantly higher in Mpox positive samples (36.9%) versus negative (21.6%) (p < 0.001). By combining PCR and serology, 66 additional patients were identified, leading to an Mpox infection rate of 48.2% (223/463) versus 33.9% when only PCR positivity is considered. Mpox infections were as such identified in 14 additional health zones and 23 additional outbreaks (111/174 (63.8%) versus 88/174 (50.6%)). Our findings highlight the urgent need of rapid on-site diagnostics to circumvent Mpox spread.

The 10th and largest Ebola virus disease epidemic in the Democratic Republic of the Congo (DRC) was declared in North Kivu Province in August 2018 and ended in June 2020. We describe and evaluate an Early Warning, Alert and Response System (EWARS) implemented in the Beni health zone of DRC during August 5, 2018–June 30, 2020. During this period, 194,768 alerts were received, of which 30,728 (15.8%) were validated as suspected cases. From these, 801 confirmed and 3 probable cases were detected. EWARS showed an overall good performance: sensitivity and specificity >80%, nearly all (97%) of alerts investigated within 2 hours of notification, and good demographic representativeness. The average cost of the system was US $438/case detected and US $1.8/alert received. The system was stable, despite occasional disruptions caused by political insecurity. Our results demonstrate that EWARS was a cost-effective component of the Ebola surveillance strategy in this setting.

Despite its critical role in containing outbreaks, the efficacy of contact tracing, measured as the sensitivity of case detection, remains an elusive metric. We estimated the sensitivity of contact tracing by applying unilist capture-recapture methods on data from the 2018–2020 outbreak of Ebola virus disease in the Democratic Republic of the Congo. To compute sensitivity, we applied different distributional assumptions to the zero-truncated count data to estimate the number of unobserved case-patients with any contacts and infected contacts. Geometric distributions were the best-fitting models. Our results indicate that contact tracing efforts identified almost all (n = 792, 99%) of case-patients with any contacts but only half (n = 207, 48%) of case-patients with infected contacts, suggesting that contact tracing efforts performed well at identifying contacts during the listing stage but performed poorly during the contact follow-up stage. We discuss extensions to our work and potential applications for the ongoing coronavirus pandemic.

Abstract Background Malaria remains a major public health concern in the Democratic Republic of Congo (DRC), and school-age children are relatively neglected in malaria prevalence surveys and may constitute a significant reservoir of transmission. This study aimed to understand the burden of malaria infections in school-age children in Kinshasa/DRC. Methods A total of 634 (427 asymptomatic and 207 symptomatic) blood samples collected from school-age children aged 6 to 14 years were analysed by microscopy, RDT and Nested-PCR. Results The overall prevalence of Plasmodium spp. by microscopy, RDT and PCR was 33%, 42% and 62% among asymptomatic children and 59%, 64% and 95% in symptomatic children, respectively. The prevalence of Plasmodium falciparum, Plasmodium malariae and Plasmodium ovale spp. by PCR was 58%, 20% and 11% among asymptomatic and 93%, 13% and 16% in symptomatic children, respectively. Among P. ovale spp., P. ovale curtisi, P. ovale wallikeri and mixed P. ovale curtisi + P. ovale wallikeri accounted for 75%, 24% and 1% of infections, respectively. All Plasmodium species infections were significantly more prevalent in the rural area compared to the urban area in asymptomatic infections (p

COVID-19 vaccination in the Democratic Republic of the Congo (DRC) began in April 2021. A month later, most COVID-19 vaccine doses were reallocated to other African countries, due to low vaccine uptake and the realization that the doses would expire before use. Based on data available on 13 August 2022, 2.76% of the DRC population had been fully vaccinated with last dose of primary series of COVID-19 vaccine, placing the country second to last in Africa and in the last five in global COVID-19 vaccination coverage. The DRC’s reliance on vaccine donations requires continuous adaptation of the vaccine deployment plan to match incoming COVID-19 vaccines shipments. Challenges in planning vaccine deployments, vaccinating priority populations, coordinating, and implementing the communications plan, disbursing funds, and conducting supervision of vaccination activities have contributed to low COVID-19 vaccine coverage. In addition, the spread of rumors through social media and by various community and religious leaders resulted in high levels of vaccine hesitancy. A strong risk communication and community engagement plan, coupled with innovative efforts to target the highest-risk populations are critical to increase vaccine uptake during the next phase of COVID-19 vaccine introduction.

Summary: Background: A paucity of data is available on virologic and biochemical characteristics of paediatric Ebolavirus disease (EVD), compared to adults. Methods: We conducted a retrospective chart review of children (7.6 log10copies/mL, alanine transaminase >525 U/L, C-reactive protein >100 mg/L, blood urea nitrogen >7.5 mmol/L, rhabdomyolysis, and.acute kidney injury. Interpretation: Paediatric EVD patients, like adults, experience multiorgan dysfunction with life-threatening electrolyte imbalances, hypoglycaemia, kidney injury, liver injury, and rhabdomyolysis. Paediatric patients have significantly higher VLs throughout the course of EVD than adults. Funding: This study was not funded.

Abstract Background Ebola Virus Disease (EVD) is a deadly and feared infectious disease, which can be responsible of debilitating physical and psychological sequelae in survivors including depression and anxiety disorders. Unfortunately, there are scarce data on survivor sequelae in Democratic Republic of the Congo. So this study assessed PTSD, depression and anxiety symptoms among EVD survivors enrolled in the follow-up program of the psychosocial care team of Beni town’s general hospital. Methods A cross-sectional study used consecutive sampling to recruit 144 Ebola virus disease survivors who came for follow up from October 23 to November 13; 2019. Basic socio-demographic data, presence of headache and short-term memory function were assessed. The Post-traumatic Checklist Scale and Hospital Anxiety and Depression Scale were used to assess psychological burden among participants. Descriptive statistics were used to summarized data and Pearson’s or likelihood chi-square were used to test association between psychiatric disorders and associated factors. Results The prevalence of PTSD, depression and anxiety was 24.3, 24.3 and 33.3% respectively. Being male (OR = 0.42, 95% CI: 0.16, 0.95, p = 0.049), suffering from persistent headache (OR = 2.62, 95% CI: 1.12, 6.14, p = 0.014), losing a loved one because of EVD (OR: 2.60, 95% CI: 1.11, 6.15, p = 0. 015) and being young − 18-24 years - (OR: 0. 261, 95% CI: 0. 08, 0.82, p = 0,026) were statistically associated with PTSD diagnosis. Having short-term memory impairment and suffering from persistent headache were statistically associated with depression and anxiety diagnoses (OR = 2.44, 95% CI: 1.03, 5.82, p = 0.026); (OR = 2.24, 95% CI: 1.04, 4.85, p = 0.025); (OR = 2.62, 95% CI: 1.12, 6.14, p = 0.014); (OR = 2.31, 95% CI: 1.06, 5.01, p = 0.020). Conclusion The prevalence of PTSD, depression and anxiety is high among EVD survivors. Development of specialized psychiatric services to sustain psychiatric and psychological health amongst survivors in the cultural context of the Eastern part of the DRC should be considered by the teams fighting against EVD in the DRC.

Abstract Background In sub-Saharan Africa, acute respiratory infections (ARI), acute gastrointestinal infections (GI) and acute febrile disease of unknown cause (AFDUC) have a large disease burden, especially among children, while respective aetiologies often remain unresolved. The need for robust infectious disease surveillance to detect emerging pathogens along with common human pathogens has been highlighted by the ongoing novel coronavirus disease 2019 (COVID-19) pandemic. The African Network for Improved Diagnostics, Epidemiology and Management of Common Infectious Agents (ANDEMIA) is a sentinel surveillance study on the aetiology and clinical characteristics of ARI, GI and AFDUC in sub-Saharan Africa. Methods ANDEMIA includes 12 urban and rural health care facilities in four African countries (Côte d’Ivoire, Burkina Faso, Democratic Republic of the Congo and Republic of South Africa). It was piloted in 2018 in Côte d’Ivoire and the initial phase will run from 2019 to 2021. Case definitions for ARI, GI and AFDUC were established, as well as syndrome-specific sampling algorithms including the collection of blood, naso- and oropharyngeal swabs and stool. Samples are tested using comprehensive diagnostic protocols, ranging from classic bacteriology and antimicrobial resistance screening to multiplex real-time polymerase chain reaction (PCR) systems and High Throughput Sequencing. In March 2020, PCR testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and analysis of full genomic information was included in the study. Standardised questionnaires collect relevant clinical, demographic, socio-economic and behavioural data for epidemiologic analyses. Controls are enrolled over a 12-month period for a nested case-control study. Data will be assessed descriptively and aetiologies will be evaluated using a latent class analysis among cases. Among cases and controls, an integrated analytic approach using logistic regression and Bayesian estimation will be employed to improve the assessment of aetiology and associated risk factors. Discussion ANDEMIA aims to expand our understanding of ARI, GI and AFDUC aetiologies in sub-Saharan Africa using a comprehensive laboratory diagnostics strategy. It will foster early detection of emerging threats and continued monitoring of important common pathogens. The network collaboration will be strengthened and site diagnostic capacities will be reinforced to improve quality management and patient care.

[This corrects the article DOI: 10.1371/journal.pntd.0009566.].

Bats are at the origin of human coronaviruses, either directly or via an intermediate host. We tested swabs from 4597 bats (897 from the Democratic Republic of Congo (DRC), 2191 from Cameroon and 1509 from Guinea) with a broadly reactive PCR in the RdRp region. Coronaviruses were detected in 903 (19.6%) bats and in all species, with more than 25 individuals tested. The highest prevalence was observed in Eidolon helvum (239/733; 39.9%) and Rhinolophus sp. (306/899; 34.1%), followed by Hipposideros sp. (61/291; 20.9%). Frugivorous bats were predominantly infected with beta coronaviruses from the Nobecovirus subgenus (93.8%), in which at least 6 species/genus-specific subclades were observed. In contrast, insectivorous bats were infected with beta-coronaviruses from different subgenera (Nobecovirus (8.5%), Hibecovirus (32.8%), Merbecovirus (0.5%) and Sarbecovirus (57.6%)) and with a high diversity of alpha-coronaviruses. Overall, our study shows a high prevalence and genetic diversity of coronaviruses in bats and illustrates that Rhinolophus bats in Africa are infected at high levels with the Sarbecovirus subgenus, to which SARS-CoV-2 belongs. It is important to characterize in more detail the different coronavirus lineages from bats for their potential to infect human cells, their evolution and to study frequency and modes of contact between humans and bats in Africa.

BackgroundThe control of Ebola virus disease (EVD) outbreaks relies on rapid diagnosis and prompt action, a daunting task in limited-resource contexts. This study develops prediction scores that can help healthcare workers improve their decision-making at the triage-point of EVD suspect-cases during EVD outbreaks.MethodsWe computed accuracy measurements of EVD predictors to assess their diagnosing ability compared with the reference standard GeneXpert® results, during the eastern DRC EVD outbreak. We developed predictive scores using the Spiegelhalter-Knill-Jones approach and constructed a clinical prediction score (CPS) and an extended clinical prediction score (ECPS). We plotted the receiver operating characteristic curves (ROCs), estimated the area under the ROC (AUROC) to assess the performance of scores, and computed net benefits (NB) to assess the clinical utility (decision-making ability) of the scores at a given cut-off. We performed decision curve analysis (DCA) to compare, at a range of threshold probabilities, prediction scores' decision-making ability and to quantify the number of unnecessary isolation.ResultsThe analysis was done on data from 10432 subjects, including 651 EVD cases. The EVD prevalence was 6.2% in the whole dataset, 14.8% in the subgroup of suspects who fitted the WHO Ebola case definition, and 3.2% for the set of suspects who did not fit this case definition. The WHO clinical definition yielded 61.6% sensitivity and 76.4% specificity. Fatigue, difficulty in swallowing, red eyes, gingival bleeding, hematemesis, confusion, hemoptysis, and a history of contact with an EVD case were predictors of EVD. The AUROC for ECPS was 0.88 (95%CI: 0.86-0.89), significantly greater than this for CPS, 0.71 (95%CI: 0.69-0.73) (p < 0.0001). At -1 point of score, the CPS yielded a sensitivity of 85.4% and specificity of 42.3%, and the ECPS yielded sensitivity of 78.8% and specificity of 81.4%. The diagnostic performance of the scores varied in the three disease contexts (the whole, fitting or not fitting the WHO case definition data sets). At 10% of threshold probability, e.g. in disease-adverse context, ECPS gave an NB of 0.033 and a net reduction of unnecessary isolation of 67.1%. Using ECPS as a joint approach to isolate EVD suspects reduces the number of unnecessary isolations by 65.7%.ConclusionThe scores developed in our study showed a good performance as EVD case predictors since their use improved the net benefit, i.e., their clinical utility. These rapid and low-cost tools can help in decision-making to isolate EVD-suspicious cases at the triage point during an outbreak. However, these tools still require external validation and cost-effectiveness evaluation before being used on a large scale.

After the 2017 Ebola virus (EBOV) outbreak in Likati, a district in northern Democratic Republic of the Congo, we sampled small mammals from the location where the primary case-patient presumably acquired the infection. None tested positive for EBOV RNA or antibodies against EBOV, highlighting the ongoing challenge in detecting animal reservoirs for EBOV.

ABSTRACTEarly 2019, a chikungunya virus (CHIKV) outbreak hit the Democratic Republic of the Congo (DRC). Though seldomly deadly, this mosquito-borne disease presents as an acute febrile (poly)arthralgia often followed by long-term sequelae. Although Aedes aegypti is the primary vector, an amino acid substitution in the viral envelope gene E1 (A226V) is causing concern as it results in increased transmission by Aedes albopictus, a mosquito with a much wider geographical distribution. Between January and March 2019, we collected human and mosquito samples in Kinshasa and Kongo Central province (Kasangulu and Matadi). Of the patients that were tested within 7 days of symptom onset, 49.7% (87/175) were RT–qPCR positive, while in the mosquito samples CHIKV was found in 1/2 pools in Kinshasa, 5/6 pools in Kasangulu, and 8/26 pools in Matadi. Phylogenetic analysis on whole-genome sequences showed that the circulating strain formed a monophyletic group within the ECSA2 lineage and harboured the A226V mutation. Our sequences did not cluster with sequences from previously reported outbreaks in the DRC nor with other known A226V-containing ECSA2 strains. This indicates a scenario of convergent evolution where A226V was acquired independently in response to a similar selection pressure for transmission by Ae. albopictus. This is in line with our entomological data where we detected Ae. albopictus more frequently than Ae. aegypti in two out of three affected areas. In conclusion, our findings suggest that CHIKV is adapting to the increased presence of Aedes albopictus in DRC.

A novel hantavirus, named Kiwira virus, was molecularly detected in six Angolan free-tailed bats (Mops condylurus, family Molossidae) captured in Tanzania and in one free-tailed bat in the Democratic Republic of Congo. Hantavirus RNA was found in different organs, with the highest loads in the spleen. Nucleotide sequences of large parts of the genomic S and L segments were determined by in-solution hybridisation capture and high throughput sequencing. Phylogenetic analyses placed Kiwira virus into the genus Mobatvirus of the family Hantaviridae, with the bat-infecting Quezon virus and Robina virus as closest relatives. The detection of several infected individuals in two African countries, including animals with systemic hantavirus infection, provides evidence of active replication and a stable circulation of Kiwira virus in M. condylurus bats and points to this species as a natural host. Since the M. condylurus home range covers large regions of Sub-Saharan Africa and the species is known to roost inside and around human dwellings, a potential spillover of the Kiwira virus to humans must be considered.

The emerging field of outbreak analytics calls attention to the need for data from multiple sources to inform evidence-based decision making in managing infectious diseases outbreaks. To date, these approaches have not systematically integrated evidence from social and behavioural sciences. During the 2018–2020 Ebola outbreak in Eastern Democratic Republic of the Congo, an innovative solution to systematic and timely generation of integrated and actionable social science evidence emerged in the form of the Cellulle d’Analyse en Sciences Sociales (Social Sciences Analytics Cell) (CASS), a social science analytical cell. CASS worked closely with data scientists and epidemiologists operating under the Epidemiological Cell to produce integrated outbreak analytics (IOA), where quantitative epidemiological analyses were complemented by behavioural field studies and social science analyses to help better explain and understand drivers and barriers to outbreak dynamics. The primary activity of the CASS was to conduct operational social science analyses that were useful to decision makers. This included ensuring that research questions were relevant, driven by epidemiological data from the field, that research could be conducted rapidly (ie, often within days), that findings were regularly and systematically presented to partners and that recommendations were co-developed with response actors. The implementation of the recommendations based on CASS analytics was also monitored over time, to measure their impact on response operations. This practice paper presents the CASS logic model, developed through a field-based externally led consultation, and documents key factors contributing to the usefulness and adaption of CASS and IOA to guide replication for future outbreaks.

BackgroundFever with jaundice is a common symptom of some infectious diseases. In public health surveillance within the Democratic Republic of the Congo (DRC), yellow fever is the only recognized cause of fever with jaundice. However, only 5% of the surveillance cases are positive for yellow fever and thus indicate the involvement of other pathogens. Leptospira spp. are the causative agents of leptospirosis, a widespread bacterial zoonosis, a known cause of fever with jaundice. This study aimed to determine the seropositivity of anti-Leptospira antibodies among suspected yellow fever cases and map the geographical distribution of possible leptospirosis in the DRC.MethodsWe conducted a retrospective study using 1,300 samples from yellow fever surveillance in the DRC from January 2017 to December 2018. Serum samples were screened for the presence of IgM against Leptospira spp. by a whole cell-based IgM ELISA (Patoc-IgM ELISA) at the Institut National de Recherche Biomedicale in Kinshasa (INRB) according to World Health Organization (WHO) guidance. Exploratory univariable and multivariable logistic regression analyses were undertaken to assess associations between socio-demographic factors and the presence of Leptospira IgM.ResultsOf the 1,300 serum samples screened, 88 (7%) showed evidence of IgM against Leptospira spp. Most positive cases (34%) were young adult males in the 20-29-year group. There were statistically significant associations between having Leptospira IgM antibodies, age, sex, and living area. Observed positive cases were mostly located in urban settings, and the majority lived in the province of Kinshasa. There was a statistically significant association between seasonality and IgM Leptospira spp. positivity amongst those living in Kinshasa, where most of the positive cases occurred during the rainy season.ConclusionsThis study showed that leptospirosis is likely an overlooked cause of unexplained cases of fever with jaundice in the DRC and highlights the need to consider leptospirosis in the differential diagnosis of fever with jaundice, particularly in young adult males. Further studies are needed to identify animal reservoirs, associated risk factors, and the burden of human leptospirosis in the DRC.

BackgroundEbola virus (EBOV) is a zoonotic filovirus spread through exposure to infected bodily fluids of a human or animal. Though EBOV is capable of causing severe disease, referred to as Ebola Virus Disease (EVD), individuals who have never been diagnosed with confirmed, probable or suspected EVD can have detectable EBOV antigen-specific antibodies in their blood. This study aims to identify risk factors associated with detectable antibody levels in the absence of an EVD diagnosis.MethodologyData was collected from September 2015 to August 2017 from 1,366 consenting individuals across four study sites in the DRC (Boende, Kabondo-Dianda, Kikwit, and Yambuku). Seroreactivity was determined to EBOV GP IgG using Zaire Ebola Virus Glycoprotein (EBOV GP antigen) ELISA kits (Alpha Diagnostic International, Inc.) in Kinshasa, DRC; any result above 4.7 units/mL was considered seroreactive. Among the respondents, 113 (8.3%) were considered seroreactive. Several zoonotic exposures were associated with EBOV seroreactivity after controlling for age, sex, healthcare worker status, location, and history of contact with an EVD case, namely: ever having contact with bats, ever having contact with rodents, and ever eating non-human primate meat. Contact with monkeys or non-human primates was not associated with seroreactivity.ConclusionsThis analysis suggests that some zoonotic exposures that have been linked to EVD outbreaks can also be associated with EBOV GP seroreactivity in the absence of diagnosed EVD. Future investigations should seek to clarify the relationships between zoonotic exposures, seroreactivity, asymptomatic infection, and EVD.

INTRODUCTION: accurate and timely laboratory diagnosis of yellow fever (YF) is critical to the Eliminate Yellow Fever Epidemics (EYE) strategy. Gavi, the Vaccine Alliance recognized the need to support and build capacity in the national and regional laboratories in the Global YF Laboratory Network (GYFLN) as part of this strategy. METHODS: to better understand current capacity, gaps and needs of the GYFLN laboratories in Africa, assessments were carried out in national and regional reference laboratories in the 25 African countries at high risk for YF outbreaks that were eligible for new financial support from Gavi. RESULTS: the assessments found that the GYFLN in Africa has high capacity but 21% of specimens were not tested due to lack of testing kits or reagents and approximately 50% of presumptive YF cases were not confirmed at the regional reference laboratory due to problems with shipping. CONCLUSION: the laboratory assessments helped to document the baseline capacities of these laboratories prior to Gavi funding to support strengthening YF laboratories.

Abstract Background Measles continues to circulate in the Democratic Republic of Congo, and the country suffered from several important outbreaks over the last 5 years. Despite a large outbreak starting in the former province of Katanga in 2010 and the resulting immunization activities, another outbreak occurred in 2015 in this same region. We conducted measles seroprevalence surveys in four health zones (HZ) in the former Katanga Province in order to assess the immunity against measles in children 6 months to 14 years after the 2015 outbreak. Methods We conducted multi-stage cluster surveys stratified by age group in four HZs, Kayamba, Malemba-Nkulu, Fungurume, and Manono. The age groups were 6–11 months, 12–59 months, and 5–14 years in Kayamba and Malemba-Nkulu, 6–59 months and 5–14 years in Manono and Fungurume. The serological status was measured on dried capillary blood spots collected systematically along with vaccination status (including routine Extended Program of Immunization (EPI), and supplementary immunization activities (SIAs)) and previous self-reported history of suspected measles. Results Overall seroprevalence against measles was 82.7% in Kayamba, 97.6% in Malemba-Nkulu, 83.2% in Manono, and 74.4% in Fungurume, and it increased with age in all HZs. It was 70.7 and 93.8% in children 12–59 months in Kayamba and Malemba-Nkulu, and 49.8 and 64.7% in children 6–59 months in Fungurume and Manono. The EPI coverage was low but varied across HZ. The accumulation of any type of vaccination against measles resulted in an overall vaccine coverage (VC) of at least 85% in children 12–59 months in Kayamba and Malemba-Nkulu, 86.1 and 74.8% in children 6–59 months in Fungurume and Manono. Previous measles infection in 2015-early 2016 was more frequently reported in children aged 12–59 months or 6–59 months (depending on the HZ). Conclusion The measured seroprevalence was consistent with the events that occurred in these HZs over the past few years. Measles seroprevalence might prove a valuable source of information to help adjust the timing of future SIAs and prioritizing support to the EPI in this region as long as the VC does not reach a level high enough to efficiently prevent epidemic flare-ups.

Despite a decade of sustained malaria control, malaria remains a serious public health problem in the Democratic Republic of Congo (DRC). Children under five years of age and school-age children aged 5–15 years remain at high risk of symptomatic and asymptomatic malaria infections. The World Health Organization’s malaria control, elimination, and eradication recommendations are still only partially implemented in DRC. For better malaria control and eventual elimination, the integration of all individuals into the national malaria control programme will strengthen malaria control and elimination strategies in the country. Thus, inclusion of schools and school-age children in DRC malaria control interventions is needed.

To clarify the role of bats in the ecology of Ebola viruses, we assessed the prevalence of Ebola virus antibodies in a large-scale sample of bats collected during 2015–2017 from countries in Africa that have had previous Ebola outbreaks (Guinea, the Democratic Republic of the Congo) or are at high risk for outbreaks (Cameroon). We analyzed 4,022 blood samples of bats from >12 frugivorous and 27 insectivorous species; 2–37 (0.05%–0.92%) bats were seropositive for Zaire and 0–30 (0%–0.75%) bats for Sudan Ebola viruses. We observed Ebola virus antibodies in 1 insectivorous bat genus and 6 frugivorous bat species. Certain bat species widespread across Africa had serologic evidence of Zaire and Sudan Ebola viruses. No viral RNA was detected in the subset of samples tested (n = 665). Ongoing surveillance of bats and other potential animal reservoirs are required to predict and prepare for future outbreaks.

BackgroundEpidemic arbovirus transmission occurs among humans by mosquito bites and the sylvatic transmission cycles involving non-human primates (NHPs) still exists. However, limited data are available on the extent in NHPs infections and their role. In this study, we have developed and validated a high-throughput serological screening tool to study the circulation of multiple arboviruses that represent a significant threat to human health, in NHPs in Central Africa.Methodology/principal findingsRecombinant proteins NS1, envelope domain-3 (DIII) for the dengue (DENV), yellow fever (YFV), usutu (USUV), west nile (WNV) and zika (ZIKV) and envelope 2 for the chikungunya (CHIKV) and o'nyong-nyong (ONNV) were coupled to Luminex beads to detect IgG directed against these viruses. Evaluation of test performance was made using 161 human sera of known arboviral status (66 negative and 95 positive). The sensitivity and specificity of each antigen were determined by statistical methods and ROC curves (except for ONNV and USUV). All NS1 antigens (except NS1-YFV), CHIKV-E2 and WNV-DIII had sensitivities and specificities > 95%. For the other DIII antigens, the sensitivity was low, limiting the interest of their use for seroprevalence studies. Few simultaneous reactions were observed between the CHIKV+ samples and the NS1 antigens to the non-CHIKV arboviruses. On the other hand, the DENV+ samples crossed-reacted with NS1 of all the DENV serotypes (1 to 4), as well as with ZIKV, USUV and to a lesser extent with YFV. A total of 3,518 samples of 29 species of NHPs from Cameroon and the Democratic Republic of Congo (DRC) were tested against NS1 (except YFV), E2 (CHIKV/ONNV) and DIII (WNV) antigens. In monkeys (n = 2,100), the global prevalence varied between 2 and 5% for the ten antigens tested. When we stratified by monkey's biotope, the arboreal species showed the highest reactivity. In monkeys from Cameroon, the highest IgG prevalence were observed against ONNV-E2 and DENV2-NS1 with 3.95% and 3.40% respectively and in DRC, ONNV-E2 (6.63%) and WNV-NS1 (4.42%). Overall prevalence was low in apes (n = 1,418): ranging from 0% for USUV-NS1 to 2.6% for CHIKV-E2. However, a very large disparity was observed among collection site and ape species, e.g. 18% (9/40) and 8.2% (4/49) of gorillas were reactive with CHIKV-E2 or WNV-NS1, respectively in two different sites in Cameroon.Conclusions/significanceWe have developed a serological assay based on Luminex technology, with high specificity and sensitivity for simultaneous detection of antibodies to 10 antigens from 6 different arboviruses. This is the first study that evaluated on a large scale the presence of antibodies to arboviruses in NHPs to evaluate their role in sylvatic cycles. The overall low prevalence (

It is very exceptional that a new disease becomes a true pandemic. Since its emergence in Wuhan, China, in late 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes COVID-19, has spread to nearly all countries of the world in only a few months. However, in different countries, the COVID-19 epidemic takes variable shapes and forms in how it affects communities. Until now, the insights gained on COVID-19 have been largely dominated by the COVID-19 epidemics and the lockdowns in China, Europe and the USA. But this variety of global trajectories is little described, analysed or understood. In only a few months, an enormous amount of scientific evidence on SARS-CoV-2 and COVID-19 has been uncovered (knowns). But important knowledge gaps remain (unknowns). Learning from the variety of ways the COVID-19 epidemic is unfolding across the globe can potentially contribute to solving the COVID-19 puzzle. This paper tries to make sense of this variability—by exploring the important role that context plays in these different COVID-19 epidemics; by comparing COVID-19 epidemics with other respiratory diseases, including other coronaviruses that circulate continuously; and by highlighting the critical unknowns and uncertainties that remain. These unknowns and uncertainties require a deeper understanding of the variable trajectories of COVID-19. Unravelling them will be important for discerning potential future scenarios, such as the first wave in virgin territories still untouched by COVID-19 and for future waves elsewhere.

Ebolaviruses pose a substantial threat to wildlife populations and to public health in Africa. Evolutionary analyses of virus genome sequences can contribute significantly to elucidate the origin of new outbreaks, which can help guide surveillance efforts. The reconstructed between-outbreak evolutionary history of Zaire ebolavirus so far has been highly consistent. By removing the confounding impact of population growth bursts during local outbreaks on the free mixing assumption that underlies coalescent-based demographic reconstructions, we find-contrary to what previous results indicated-that the circulation dynamics of Ebola virus in its animal reservoir are highly uncertain. Our findings also accentuate the need for a more fine-grained picture of the Ebola virus diversity in its reservoir to reliably infer the reservoir origin of outbreak lineages. In addition, the recent appearance of slower-evolving variants is in line with latency as a survival mechanism and with bats as the natural reservoir host.

INTRODUCTION: La qualité des soins est essentielle pour sauver des vies humaines de différentes ma-ladies. Cependant, un diagnostic inapproprié ne peut en aucun cas aboutir à une prise en charge correcte des patients ainsi qu´à des soins de qualité. Nous avons effectué une analyse descriptive transversale dans trois laboratoires des hôpitaux généraux en République démocratique du Congo. METHODES: une équipe d´experts nationaux dans le domaine des laboratoires avait conduit l´enquête au niveau de trois laboratoires cliniques des hôpitaux généraux de la République Démocratique du Congo. Des observations, visites et entretiens structurés à l´aide d´un questionnaire ont été utilisées pour évaluer la performance de ces labora-toires cliniques. Nous avons également utilisé un guide d´évaluation développée au niveau national pour l´évaluation des laboratoires. RESULTATS: les laboratoires cliniques des hôpitaux généraux visités ont présenté de nombreux déficits notamment en ce qui concerne les infrastructures, la formation de base et continue des personnels, les équipements, la supervision et le contrôle de qualité. Le plateau technique de ces laboratoires n´était pas adapté pour répondre aux besoins de la population en ce qui concerne les maladies fréquemment rencontrées dans ces zones. Nous avons également noté que, ces laboratoires sont peu ou presque pas accompagnés et qu´il n´y avait aucune équipe de coordination dédiée à la supervision et évaluation des laboratoires au niveau de l´hôpital, voire même au niveau de la zone de santé. En plus, les techniciens de ses différents laboratoires n´ont pas été supervisés pendant de nombreuses années. CONCLUSION: les laboratoires cliniques doivent être améliorés pour permettre un diagnostic adéquat de différentes maladies. Cette amélioration doit s´appuyer sur les maladies locales. Au sein du système, il est important de consacrer plus d´attention aux laboratoires cliniques. Un plaidoyer pour cette composante négligée du système de santé est nécessaire, car cette situation pourrait être la même dans de nombreux pays en voie de développement.