The ongoing mpox clade Ib outbreak was first detected in the eastern Democratic Republic of Congo (DRC) and was associated with sexual transmission. It emerged in Kamituga, a mining city and spread rapidly in surrounding health zones and reached cities like Bukavu and Goma. Here, we describe the clinical, epidemiological, and virological characteristics of the first case of clade Ib in Kinshasa, the capital city in the western DRC. The case involved a young adult woman from Kinshasa who reported unprotected sexual contact with an occasional partner, a former friend, and subsequently developed genital lesions, including vesicles and pustules. These lesions evolved and spread to the entire body, including the limbs, eyes, and soles. The diagnosis was confirmed by PCR and sequencing allowed us to assign clade Ib. We show that infection with mpox clade Ib through sexual transmission can lead to limbal nodular keratoconjunctivitis and focal conjunctivitis as complications. Importantly, these results suggest that clade Ib may have been circulating silently in Kinshasa prior to the official declaration by the Ministry of Health. This also raises concerns about the potential risk of global spread, as is currently being observed. Further studies are needed to investigate whether subsequent outbreaks of clade Ib in Kinshasa may have emerged independently of introductions from Kivu, pointing to a more complex pattern of co-circulation that could define the mpox epidemic in the capital.

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.

Background: Poliomyelitis is a vaccine-preventable disease, with oral poliomyelitis vaccines (OPVs) and injectable poliomyelitis vaccines. In the Democratic Republic of the Congo (DRC), circulating vaccine-derived polioviruses (VDPVs) persist due to intrinsic and extrinsic factors, including the quality of the cold chain, which may make the vaccines less effective. This study’s objective was to evaluate the cold chain’s quality of OPVs and its effect on the vaccine’s viability and potency at different levels in health systems in Kinshasa. Methods: A cross-sectional study was conducted in Kinshasa, collecting OPVs at different levels of the health pyramid. Vaccine viability was assessed by cell culture using a modified World Health Organization (WHO) protocol, and the viral titer was determined using the Karber formula. The vaccine titer was classified as “very good”, “good”, or “poor” according to the WHO standard’s viral titer. Results: A total of 53 vaccines were collected and analyzed, compressing 38 bivalent oral poliomyelitis (bOPV) vaccines and 15 novel oral poliomyelitis vaccines, type 2 (nOPV2). The viral titer ranged from log10^5.8 to log 10^7.3 and from log10^5.4 to log10^8.9 for the nOPV2 and the bOPV, respectively. Of these 53 vaccine samples, 10% of the bOPVs showed viral titers below the recommended WHO threshold (>10⁶ CCID₅₀/dose), 100% of the nOPV2 had viral titers within the WHO standards (>10⁵ CCID₅₀/dose), and a significant decline in the viral titer was observed for both types of vaccines (nOPV2 and bOPV) as the distribution progressed along the level of the health pyramid. Conclusions: This study demonstrated that the viral titer of OPV declined from central to peripheral areas in routine and campaign strategies in Kinshasa.

This study aimed to assess mpox virus (MPXV) seroprevalence in South Kivu, Democratic Republic of the Congo, where a large mpox outbreak started at the end of 2023. A community-based surveys was conducted in urban (April–May 2023) and rural (July–August 2024) areas and a multiplex serological assay to detect anti-IgG against MPXV has been used. MPXV seroprevalence was 3.3% in the urban survey (n = 1174) and 8.3% in the rural survey (n = 981), with differences according to health zone (P = .004) after the mpox outbreak. This study shows temporal and geographic variation in MPXV seroprevalence and suggest potential spread of mpox in the general population in South Kivu.

Background/Objectives: Diagnosing Ebola virus disease (EVD) based solely on clinical signs remains challenging in settings where its manifestations overlap with other endemic infections. This study aimed to validate a Bayesian clinical diagnostic model to support decision-making for suspected EVD cases in resource-limited settings without access to laboratory confirmation. Methods: We conducted a retrospective analysis using data from the 10th Ebola outbreak in the Democratic Republic of the Congo (2018–2020). Clinical information from 450 suspected and laboratory-confirmed EVD cases was evaluated by seven epidemiological surveillance experts. Data were analyzed using descriptive statistics, binary logistic regression, discriminant analysis, and receiver operating characteristic (ROC) curves to assess diagnostic performance. Results: At the predefined 0.80 threshold, the SBM showed a sensitivity of 82.4%, specificity of 33.7%, PPV of 80.5%, and NPV of 36.5%. Balanced accuracy was 58.0%, with LR+ of 1.24 and LR− of approximately 0.52. Thus, although the model identified a relatively high proportion of RT-PCR confirmed cases, its ability to discriminate non-EVD cases was limited. At the symptom level, vomiting (p = 0.003), anorexia (p = 0.041), abdominal pain (p = 0.024), and muscle pain (p = 0.006) were independently linked to confirmed cases. Conclusions: This Bayesian model shows potential as a decision support tool for early identification of EVD in settings lacking laboratory capacity. Its use could improve case detection and support outbreak response in resource-limited contexts. The expert-derived SBM showed relatively high sensitivity but limited specificity in this selected outbreak cohort. These findings support further recalibration and independent validation rather than use of the model as a stand-alone diagnostic tool.

Background: Environmental surveillance (ES) of wastewater was introduced by the Global Polio Eradication Initiative (GPEI) to improve the sensitivity of acute flaccid paralysis (AFP) surveillance. In the Democratic Republic of the Congo (DRC), ES for poliovirus has been implemented since 2017. This study assessed its sensitivity and productivity. Methods: A retrospective descriptive study using ES for poliovirus data collected in the DRC between September 2017 and June 2025. Wastewater samples were analyzed at the National Institute for Biomedical Research (INRB), using a standardized algorithm that included concentration, cell culture, real-time reverse transcription polymerase chain reaction (rRT-PCR), and VP1 sequencing. Site sensitivity was assessed by productivity, defined as a viral isolation rate ≥ 50%. Results: A total of 2491 wastewater samples were collected. ES expanded from 6 sites in 3 provinces to 27 sites across 8 provinces. Overall site productivity was 33.9% (846/2491 cultures positive for enteroviruses), showing significant variability between sites and over time, which sometimes led to site closures. Non-polio enteroviruses were the most commonly isolated viruses. Among poliovirus isolates, Sabin-like strains (types 1, 2, and 3), novel oral poliovirus vaccine type 2 (nOPV2), and vaccine-derived poliovirus type 2 (VDPV2) were identified, with VDPV2 representing 13.1%. No wild poliovirus was detected. Conclusion: ES for poliovirus has expanded in the DRC, helping detect vaccine-derived poliovirus circulation and confirming the absence of wild poliovirus. Despite ongoing operational and logistical challenges causing fluctuations in site productivity, this study emphasizes the vital role of ES as a supplement to AFP surveillance.