Ebola disease
Orthoebolaviruses
Last updated 19 May 2026
Overview
Ebola disease is a disease caused by a group of Orthoebolaviruses which causes severe, often fatal illness in humans.
Disease epidemiology
Ebola disease, first identified in 1976 in southern Sudan and the Democratic Republic of the Congo (DRC), primarily affects remote villages in Central and West Africa. Case fatality ratio (CFR) is around 50%, and ranges from 25% and 90%. On 15 May 2026, the World Health Organization (WHO) confirmed a new outbreak of Ebola disease caused by Bundibugyo virus in DRC. Uganda's Ministry of Health also confirmed lab-confirmed cases, including at least one death, in Kampala involving travellers from DRC. On 16 May 2026, the WHO declared the Ebola disease outbreak in the DRC and Uganda a public health emergency of international concern.
Pathogen(s)
Orthoebolaviruses are a single-stranded RNA virus belonging to the Filoviridae family. The genus Orthoebolavirus is divided into six species.
Four have caused human infections:
Zaire/Ebola virus (EBOV)
Sudan virus (SUDV)
Bundibugyo virus (BDBV)
Taï Forest virus (TAFV)
Two others have not caused human infections to date:
Reston virus (non-pathogenic in human) (RESTV)
Bombali virus (non-pathogenic in human) (BOMV)
The presumptive hosts of Ebolavirus are fruit bats of the family Pteropodidae.
Transmission
Transmission can occur through direct contact with:
Blood, body fluids or secretions of infected persons
Tissues or body fluids of infected animals
Contaminated objects
Incubation period: Typically 5 to 15 days; range is 2 to 21 days.
Infectious period: Infected individuals are not contagious during the incubation period and become infectious once they begin to develop symptoms. They remain infectious as long as the virus is present in the blood or body fluid. The virus can persist in semen of survivors and be transmitted sexually after recovery. Pregnant women who recover from Ebola disease may still carry the virus in breastmilk, or in pregnancy-related fluids and tissues.
Clinical features
Initial symptoms include sudden onset of fever, weakness, malaise, muscle pain, joint pain, headache and sore throat.
This can be followed by vomiting, diarrhoea, abdominal pain, rash, red eyes, confusion, shortness of breath, chest pain, impaired liver and renal function, internal and external bleeding.
Risk factors
Risk factors include:
Unprotected exposure to blood and body fluids or secretions from infected or deceased patients (including in labs, burials or funerals), or infected animals
Direct contact with environments contaminated with a patient’s infectious body fluids
Diagnosis
Diagnosis during acute infection is primarily by detection of Orthoebolavirus by polymerase chain reaction (PCR) in blood specimens.
Samples can be sent to NPHL for diagnosis. NPHL will provide laboratory support and guidelines for testing, including protocols for specimen transport, testing and reporting.
Treatment and management
For all types of Ebola disease, supportive care remains as the mainstay treatment. This includes diagnosis and treatment of concomitant infections such as malaria or bacterial infections in febrile returning travellers, management of fluids and electrolytes, blood product support for haemorrhage, and support for multi-organ dysfunction, including renal replacement therapy if needed.
During outbreak settings, there are monoclonal antibodies (mAb114 (ansuvimabTM) or REGN-EB3 (InmazebTM)) recommended by WHO as adjunctive treatment in addition to supportive care where there is expected efficacy. For other Ebola diseases, there are no approved therapeutics, but candidate products are under development and a CORE protocol for clinical trials is available. There are no approved therapeutics for BDBV.
Precaution, prevention, and control
General advice
All staff who come into direct contact with a suspected or confirmed Ebola disease case or their body fluids, including (but not limited to) healthcare workers, persons responsible for transporting patients (e.g., ambulance staff), and cleaners should apply extra infection control measures and wear enhanced personal protective equipment (PPE) comprising of:
Disposable fluid-resistant hood to cover the head and neck areas (staff with long hair may wish to use head cover prior to wearing hood)
Eye protection gear (e.g., disposable downward face shields secured at forehead or goggles)
Fluid-repellent N95 mask
Inner and outer disposable fluid-resistant (AAMI 4) gown (should extend to below knee)
12-inch double nitrile or latex gloves certified for healthcare use (extended cuffs should reach up to mid forearm)
Disposable fluid resistant boot covers (should extend up to knee-height)
Patients who are under investigation for Ebola disease, pending transfer to the High-Level Isolation Unit (HLIU) at the National Centre for Infectious Diseases (NCID), should be isolated in an Airborne Infection Isolation Room (AIIR), at a minimum.
Only essential staff who have been pre-identified and trained in the donning and removal of PPE should attend to the patient. Staff attending to suspect Ebola disease cases should be closely monitored (e.g., twice daily temperature monitoring), even if they wear the appropriate PPE. Entry of non-essential staff to the patient’s room should be restricted. A register of all staff who enter the patient’s room should be maintained. Visitors should not be allowed.
Waste generated from suspect patients should be double bagged, sealed and disposed by a licensed waste-contractor. Environmental surfaces should be cleaned and disinfected using 5,000 ppm sodium hypochlorite. Disinfectants should be applied (not sprayed) before cleaning. Surface contaminated with blood, other body fluids, secretions or excretions spill, should be disinfected using 10,000 ppm sodium hypochlorite after the spill is removed using solidifiers or absorbent powder.
Persons with skin or mucosal exposure to body fluids from a suspect Ebola disease case should immediately wash the affected skin surfaces with soap and water. Mucous membranes (e.g., conjunctiva) should be irrigated with copious amounts of water or eyewash solution. Exposed persons should immediately seek advice from an Infectious Diseases physician and report the exposure to CDA.
CDA will conduct contact tracing for contacts and take appropriate follow-up actions, such as quarantine, phone surveillance, or self-monitoring. Contacts may also be referred to NCID for assessment.
Vaccination
There are currently two licensed Ebola vaccines overseas, but these vaccines are not registered in Singapore.
The vaccine rVSV-ZEBOV, while approved to protect against Ebola caused by EBOV virus, does not provide cross protection against infection caused by other species.
The Ad26.ZEBOV/MVA-BN-Filo vaccine has only been approved against EBOV and has not been tested against other species. This vaccine is administered on a two-dose schedule and requires 56 days between the two doses. The first dose provides protection against the EBOV and the second dose was designed to provide protection against other species of the virus, including SUDV, but does not include BDBV. However, this multiantigen protection has not been demonstrated with clinical data.
Notification
Ebola disease is an emerging infectious disease and is legally notifiable in Singapore. Suspected cases will be transferred to NCID on a case-by-case basis. All confirmed Ebola disease cases will be managed at the High-Level Isolation Unit (HLIU) in NCID.
Who should notify:
Medical Practitioners
Laboratories
When to notify:
On clinical suspicion or laboratory confirmation
How to notify:
Please refer to the Infectious Disease Notification for more information.
Notification timeline:
Immediately
Resources
For more information on Ebola disease, please refer to WHO website.