Kenya’s Ebola outbreak has renewed focus on the country’s ability to detect infections early, trace exposed people and protect health workers, as new Africa CDC and World Health Organisation guidelines outline updated measures for responding to Ebola and other filovirus diseases.
“Contact persons of probable and confirmed cases of filovirus disease should be listed and followed up for 21 days,” the guidelines state, underscoring the importance of sustained monitoring to identify infections before they lead to further transmission.
Titled Surveillance, Case Investigation and Contact Tracing in Filovirus Disease Outbreaks, the guidance updates the 2015 Ebola contact-tracing guidelines and covers the full surveillance process, from routine monitoring and early warning systems to outbreak investigations, epidemiological analysis and community engagement.
It comes as Kenya responds to locally transmitted cases of Bundibugyo Ebola linked to a patient who travelled from the Democratic Republic of Congo through Uganda before arriving in Nairobi.
Kenya had confirmed eight cases, including one death, by October 18, according to the latest available figures. The Ministry of Health said four additional cases announced on October 17 involved three health workers who had attended to the index patient and one male relative. All were already in quarantine when they tested positive.
The infections highlight the importance of identifying people exposed to the virus before they develop symptoms, while ensuring that health workers caring for patients are adequately protected.
The guidelines identify five key areas: routine surveillance in humans and wildlife, early warning and alert systems, outbreak investigation and contact tracing, epidemiological analysis, and community engagement throughout the response.
They are intended for public health practitioners, epidemiologists, surveillance officers, laboratory personnel and field responders. The document does not replace national protocols, which should be developed in accordance with national legislation and the International Health Regulations.
Contacts to be followed for 21 days
The recommended 21-day follow-up period is intended to help health teams identify contacts who develop symptoms after exposure and intervene quickly to limit further transmission.
“Contact tracing involves identifying people who may have been exposed to an infected person, assessing the nature of the exposure, locating them and monitoring their health. Depending on the circumstances, contacts who develop symptoms may require testing, isolation and further public health assessment.”
The guidelines also stress that tracing must extend across national borders.
“Identifying, notifying and following up contact persons across international borders (if applicable) is an integral component of outbreak control and must be planned from the outset,” the document states.
The recommendation is particularly relevant in East Africa, where people routinely cross borders for trade, work, family visits and healthcare.
The guidance calls for countries to establish clear channels for sharing information about exposed travellers, including their travel itineraries, dates of last exposure and the remaining monitoring period. Follow-up should continue when contacts move between countries to avoid gaps in surveillance.
Cross-border coordination is therefore not an optional addition to outbreak response. It must be built into contact tracing from the beginning, with health authorities able to notify their counterparts and maintain follow-up when people cross into another jurisdiction.
Early detection and better surveillance
The guidance calls for surveillance systems capable of detecting unusual illnesses and deaths, investigating alerts and identifying potential outbreaks before transmission expands. It also recommends maintaining surveillance for other diseases during filovirus outbreaks, rather than allowing the emergency response to overshadow routine public health monitoring.
Early symptoms of Ebola, including fever and fatigue, can resemble those of other illnesses. Laboratory testing and assessment of a patient’s exposure history are therefore essential in determining whether an infection is linked to an outbreak.
The guidelines encourage countries to analyse surveillance data systematically and use the findings to guide response decisions. They also call for stronger coordination among surveillance teams, laboratories, healthcare facilities and other responders so that alerts are investigated and results communicated promptly.
In Kenya, the detection of additional infections among people already in quarantine illustrates how contact tracing can identify cases before they are detected through wider community surveillance.
However, finding cases is only one part of the response. Health teams must also isolate patients safely, investigate their contacts and prevent further exposure in healthcare facilities and communities.
Health workers at risk
The infection of three health workers linked to Kenya’s index patient has brought infection prevention and control into sharper focus.
Healthcare workers may be exposed while examining patients, collecting samples, providing treatment or handling contaminated materials. The guidelines stress the need for appropriate training, protective measures and coordination among teams responding to filovirus outbreaks.
Early recognition of suspected cases and prompt implementation of infection prevention measures are critical to reducing the risk of transmission in health facilities.
The guidance also emphasises that surveillance and contact-tracing teams must work alongside community engagement and risk communication personnel.
“All surveillance activities that involve interaction with the community should be supported and coordinated with risk communication and community engagement teams,” the document states.
Effective communication can help address fear and misinformation, encourage people to report symptoms and reduce the risk of contacts avoiding health authorities. It can also help communities understand why monitoring and other public health measures are necessary.
The guidelines further emphasise protecting personal information collected during investigations, with data shared only as necessary for public health purposes.
No one-size-fits-all response
The guidance recognises that outbreak responses must account for local conditions, available resources and the ways communities live and move.
In border areas where people regularly cross into neighbouring countries, surveillance and contact tracing require coordination between health authorities on both sides. Community engagement is equally important to ensure public health interventions are understood and accepted.
The document advises that surveillance information should be analysed in context and shared with relevant stakeholders, including affected communities.
Bundibugyo Ebola is caused by a different virus from the Zaire strain responsible for several previous Ebola outbreaks. There is currently no approved vaccine or specific treatment for Bundibugyo virus disease, making early detection, supportive care, infection prevention and rapid identification of contacts particularly important.
The effectiveness of the guidelines will ultimately depend on how consistently countries translate them into practice, including whether surveillance systems, laboratories, health facilities and cross-border teams can work together quickly when new alerts emerge.
