ETIDIOH - NEW

  {Summary} Overall risk and confidence Overall risk -- National: High  -- Regional: Moderate    -- Global: Low    Confidence in available information  -- National: Moderate -- Regional: Moderate -- Global: Moderate Risk statement On 1 September 2025, WHO received an alert from the Ministry of Health of the Democratic Republic of the Congo (DRC) regarding suspected cases of Ebola virus disease (EVD) in the Bulape Health Zone , Kasai Province , DRC.  The first currently known suspected EVD case was admitted to the Bulape General Reference Hospital on 20 August 2025 and reported to have died five days later (25 August 2025). This is a 34-year-old female patient with a 34-week gestational age who presented with fever, bloody diarrhoea, followed by anal, oral, and nasal haemorrhage, vomiting , and asthenia .  She reportedly died on 25 August 2025, with a clinical picture of multiple organ failure.  Two of the contacts of this first case (a m...

  ABSTRACT Ebola virus (EBOV), the causative agent of Ebola virus disease, remains one of the World Health Organization’s top 10 threats to global health . Infectious EBOV virions can be found on the surface of skin late in infection and may be transmitted to others through skin-to-skin contact . We investigate in vivo EBOV tropism and the kinetics of virus movement to and from the skin. Increasing viral loads were detected over time in the skin of EBOV-infected non-human primates and mice , with antigen detected in dermal stromal and immune cells . Epidermal cells within and surrounding hair follicles also harbored viral antigen , suggesting a novel mechanism of virus egress to the epidermal surface. During late infection, proinflammatory responses were elevated in infected visceral organs but minimal in the skin despite significant viral loads. We observed similar viral trafficking and cell tropism in the skin of mice intraperitoneally infected with a low containment EBOV model v...

  Abstract Background On September 27, 2024, Rwanda reported an outbreak of Marburg virus disease (MVD), after a cluster of cases of viral hemorrhagic fever was detected at two urban hospitals. Methods We report key aspects of the epidemiology, clinical manifestations, and treatment of MVD during this outbreak, as well as the overall response to the outbreak. We performed a retrospective epidemiologic and clinical analysis of data compiled across all pillars of the outbreak response and a case-series analysis to characterize clinical features, disease progression, and outcomes among patients who received supportive care and investigational therapeutic agents. Results Among the 6340 patients with suspected MVD who underwent testing, 66 had laboratory-confirmed MVD , 51 (77%) of whom were health care workers. The median estimated incubation period was 10 days (interquartile range, 8 to 13), and symptom onset occurred a median of 2 days (interquartile range, 1 to 3) before hospital ad...

  Abstract Risk of death for both mother and fetus following Ebola virus infection is extremely high . In this study, healthy women in Rwanda aged ≥18 years were randomized to two-dose Ebola vaccination (Ad26.ZEBOV, MVA-BN-Filo) during pregnancy (group A) or postpartum (group B). Unvaccinated pregnant group B women served as control. This was a parallel, randomized, controlled, open-label, single-center trial to evaluate the safety (primary endpoint—outcomes of interest and serious adverse events (SAEs)) and immunogenicity (secondary endpoint) of the two-dose Ebola vaccination. Among 3,484 women screened, 2,013 were randomized, and 2,012 women and 1,945 infants born alive were descriptively analyzed . Adverse outcomes of interest occurred in women ( 5.2% in group A and 7.3% in group B ) and infants ( 26.0% in group A and 25.6% in group B ). The most common maternal outcome of interest was pathways to preterm birth (3.2% in group A and 3.4% in group B), and the most common infant ou...

Abstract Sudan virus (SUDV) causes highly lethal outbreaks of hemorrhagic disease throughout Africa , but there has yet to be an approved vaccine or therapeutic to combat this public health threat. The most common route of natural exposure to filoviruses is through mucosal contact which greatly impacts initial viral replication. Historically, SUDV animal models used an intramuscular infection route . Here, we sought to further characterize an animal model using mucosal challenge routes and compared the impact that intramuscular, intranasal, or aerosol exposure had on SUDV pathogenicity in a ferret model . We determined that the route of infection did not significantly impact overall SUDV pathogenicity; only subtle changes were detected in magnitude of viremia and oral viral shedding. Additionally, we sought to determine if preexisting Lloviu virus (LLOV) immunity could protect ferrets from lethal SUDV infection. We found that the previous immunity elicited by LLOV infection was not suf...

{Summary} HIGHLIGHTS •  The investigation demonstrated a high level of tolerance of EBOV to thermal disinfection. •  A water-bath is recommended and the tubes should be fully submerged during the process. •  The established inactivation guidelines should be followed very strictly. Dear Editor, Viruses of the genus Orthoebolavirus cause sporadic outbreaks of severe haemorrhagic fever, with case fatality rates ranging from 25% to 90% (Mahanty and Bray, 2004). Six species of the virus (Orthoebolavirus zairense, sudanense, bundibugyoense, taiense, restonense, and bombaliense) have so far been identified (Biedenkopf et al., 2023). Among these, Orthoebolavirus zairense , commonly known as Ebola virus (EBOV), stands out as the most virulent . Given its high contagiousness and lethality, EBOV must be manipulated under biosafety level 4 (BSL-4) conditions, as stipulated by the National Health Commission of the People's Republic of China's list of human pathogenic microorganisms. P...

ABSTRACT A cocktail of human monoclonal antibodies 1C3 and 1C11 previously protected macaques from a lethal exposure to either Ebola virus (EBOV) or Sudan virus (SUDV). 1C3 is of particular interest because its paratope strongly binds with unique stoichiometry to the glycoprotein head of several orthoebolaviruses , resulting in neutralization of EBOV and SUDV . Therefore, we evaluated the protective activity of 1C3 as a standalone therapeutic in macaques exposed to either EBOV or SUDV. Two doses of 1C3 monotherapy, administered 4 and 7 days post-exposure, did not protect SUDV-exposed macaques and partially protected EBOV-exposed macaques . Notably, in a macaque that succumbed to EBOV infection, we identified two mutually exclusive escape mutations that emerged immediately after the first dose and resulted in two amino acid changes at the 1C3 binding site . We also detected a subconsensus treatment-emergent mutation likely affecting the 1C3 binding site in all three deceased SUDV-expose...

Abstract Background .  Sudan virus (SUDV) has caused multiple outbreaks in Uganda over the past two decades, leading to significant morbidity and mortality . The recent outbreaks in 2022 and 2025 highlight the ongoing threat posed by SUDV and the challenges in its containment. This study aims to characterize the epidemiological patterns and phylogenomic evolution of SUDV outbreaks in Uganda, identifying key factors influencing transmission and disease severity.  Methods .  We conducted a retrospective observational study analyzing epidemiological and genomic data from SUDV outbreaks in Uganda between 2000 and 2025. Epidemiological data were collected from official sources, including the Ugandan Ministry of Health and the World Health Organization, supplemented with reports from public health organizations. Genomic sequences of SUDV were analyzed to investigate viral evolution and identify genetic variations associated with pathogenicity and transmissibility.  Results...

Abstract The Sudan virus (SUDV) outbreaks in Uganda in 2022 and 2025 created public health concerns in-country and the entire East African region. There are currently no licensed countermeasures against SUDV . We developed a SUDV vaccine candidate based on a nanocarrier (LIONTM) complexed with an alphavirus-based replicon RNA . Here, we compare the protective efficacy of the LION-SUDV vaccine either encoding the SUDV glycoprotein (GP) alone or in combination with the Ebola virus (EBOV) GP (LION-Combination). A LION-EBOV vaccine which is protective against EBOV was also included to determine the potential for cross-protection against SUDV infection . Single-dose vaccinations were conducted three weeks before challenge with a lethal dose of guinea pig-adapted SUDV using a female guinea pig disease model. We demonstrate 100% survival and protection with the LION-SUDV and the LION-Combination vaccines, while the LION-EBOV vaccine achieved 50% protection. Antigen-specific humoral responses ...

{Summary} Situation at a glance On 26 April 2025, the Ministry of Health (MoH) of Uganda declared the end of the Sudan virus disease (SVD) outbreak after two consecutive incubation periods (a total of 42 days) since the last person confirmed with SVD tested negative for the virus on 14 March 2025.  A total of 14 SVD cases (including 12 confirmed cases and two probable cases) including four deaths (two confirmed and two probable) have been reported during this outbreak.  WHO and partners provided technical , operational and financial support to the government to contain the outbreak.  Although the outbreak has been declared over , health authorities are maintaining surveillance to rapidly identify and respond to any re-emergence.  Risk communication and community engagement will also continue to ensure the community stay informed and stigma to those who were affected is minimized. (...) Source: World Health Organization,  https://www.who.int/emergencies/disease-o...

Abstract In 2018, a clinical trial of four investigational therapies for Ebola virus disease (EVD), known as the PALM trial , was conducted in the Democratic Republic of Congo . All patients received either the antiviral remdesivir (RDV) or a monoclonal antibody product : ZMapp, mAb114 (Ebanga), or REGN-EB3 (Inmazeb). The study concluded that both mAb114 and REGN-EB3 were superior to ZMapp and RDV in reducing mortality from EVD. However, the data suggested that some patients in the RDV and ZMapp groups might have been sicker at the time of treatment initiation. Here, we assessed the efficacy of each of these therapies in a uniformly lethal rhesus monkey model of EVD when treatment was initiated 5 days after Ebola exposure. Treatment with RDV, mAb114, REGN-EB3, and ZMapp each resulted in similar survival (approximately 40% ). Survival was associated with circulating viral load at treatment initiation. A trend of more escape mutants in the GP1 and GP2 domains was observed for the mAb114 ...

Abstract In February 2023, the government of Equatorial Guinea declared an outbreak of Marburg virus disease . We describe the response structure and epidemiologic characteristics , including case-patient demographics, clinical manifestations, risk factors , and the serial interval and timing of symptom onset, treatment seeking, and recovery or death . We identified 16 laboratory-confirmed and 23 probable cases of Marburg virus disease in 5 districts and noted several unlinked chains of transmission and a case-fatality ratio of 90% (35/39 cases). Transmission was concentrated in family clusters and healthcare settings . The median serial interval was 18.5 days ; most transmission occurred during late-stage disease . Rapid isolation of symptomatic case-patients is critical in preventing transmission and improving patient outcomes; community engagement and surveillance strengthening should be prioritized in emerging outbreaks. Further analysis of this outbreak and a One Health surveillan...

Abstract Ebola virus (EBOV) and Marburg virus (MARV) are zoonotic filoviruses that cause hemorrhagic fever in humans . Correlative data implicate bats as natural EBOV hosts , but neither a full-length genome nor an EBOV isolate has been found in any bats sampled. Here, we model filovirus infection in the Jamaican fruit bat (JFB), Artibeus jamaicensis, by inoculation with either EBOV or MARV through a combination of oral, intranasal, and subcutaneous routes . Infection with EBOV results in systemic virus replication and oral shedding of infectious virus. MARV replication is transient and does not shed. In vitro, JFB cells replicate EBOV more efficiently than MARV, and MARV infection induces innate antiviral responses that EBOV efficiently suppresses. Experiments using VSV pseudoparticles or replicating VSV expressing the EBOV or MARV glycoprotein demonstrate an advantage for EBOV entry and replication early , respectively, in JFB cells. Overall, this study describes filovirus species-sp...

Situation at a glance On 13 March 2025, the Ministry of Health of the United Republic of Tanzania declared the end of the Marburg virus disease (MVD) outbreak.  This declaration came after two consecutive incubation periods (a total of 42 days) since the last person confirmed with MVD died on 28 January 2025 and was given a safe and dignified burial, in accordance with WHO recommendations.  No new confirmed cases were reported since then.  The outbreak was declared on 20 January 2025 . As of 12 March 2025, two confirmed and eight probable cases were reported by the Ministry of Health from Biharamulo district in Kagera region. All 10 cases died (case fatality ratio 100%), including eight who died before the confirmation of the outbreak. A total of 272 contacts that were listed for monitoring completed their 21-day follow-up as of 10 February 2025. WHO, through its country office, and partners provided technical, operational and financial support to the government to contai...

Situation at a glance Since the outbreak of Sudan virus disease (SVD) was declared in Uganda on 30 January 2025, and as of 5 March 2025, a total of 14 cases (including 12 confirmed cases and two probable cases) including four deaths (two confirmed and two probable) have been reported.  On 1 March 2025, the Ministry of Health released a press statement confirming the tenth case . The patient was a child under 5 years old who presented and died in the Mulago hospital on 23 February 2025.  As of 5 March, two additional confirmed cases and two probable deaths have been reported that are linked to this case. Both of these cases are currently admitted to treatment facilities.  Eight confirmed cases received care at treatment centres in the capital Kampala and in Mbale and were discharged on 18 February 2025.  As of 5 March 2025, 192 new contacts have been identified and are under follow-up in Kampala, Ntoroko and Wakiso. In the absence of licensed vaccines and therapeutics...

{Excerpt} Situation at a glance As of 20 February 2025, a total of nine confirmed cases of Sudan virus disease, including one death have been reported from Uganda , since the outbreak was declared on 30 January 2025. Eight cases received care at treatment centres in the capital Kampala and in Mbale and were discharged on 18 February after two negative tests 72 hours apart.  As of 20 February 2025, 58 contacts that have been identified are still under follow up in designated quarantine facilities located in Jinja, Kampala,and Mbale .  Sudan virus disease belongs to the same family as Ebola virus disease . It is caused by Sudan virus (SUDV). It is a severe disease with high case fatality ranging from 41% to 70% in past outbreaks. In the absence of licensed vaccines and therapeutics for the prevention and treatment of SVD, the risk of potential serious public health impact is high. Early detection, diagnosis, and optimized supportive care may increase the chance of survival. Desc...

 {Excerpt} Situation at a glance Since the declaration of the Marburg Virus Disease (MVD) outbreak on 20 January 2025 in the United Republic of Tanzania, one additional confirmed death was reported by the Ministry of Health from the epicentre of the outbreak in Biharamulo district in Kagera region .  As of 10 February 2025, a cumulative of two confirmed and eight probable cases were reported by the Ministry of Health.  All 10 cases have died , including eight who died before the confirmation of the outbreak.  As of 10 February 2025, all 281 contacts that were listed and under monitoring have completed the 21-day follow-up.  The Ministry of Health developed a national response plan to guide activities. Additionally, a national rapid response team was deployed to the affected region to enhance outbreak investigation and response, with technical and operational support from WHO and health partners. Description of the situation Since the previous Disease Outbreak Ne...