The outbreak of Ebola virus disease in west Africa continues to evolve, with cases confirmed in Guinea, Liberia, Nigeria, and Sierra Leone. At present, no cases have been confirmed anywhere else in the world outside these 4 countries.
The situation in Lagos, Nigeria, where the first imported case was detected in July, looks reassuring. At present, the city’s 12 confirmed cases are all part of a single chain of transmission. Those infected by the initial case include medical staff involved in his treatment, a patient in the same hospital, and a protocol officer in very close contact with the patient.
The initial patient was vomiting frequently during travel and upon arrival. No one on the same flight was infected.
The full recovery to date of one infected contact is additional good news. It counters the widespread perception that infection with the Ebola virus is invariably a death sentence. Evidence suggests that early detection and supportive therapy increase the prospects of survival.
Intensive contact tracing, conducted by Nigerian health officials and staff from the US Centers for Disease Control and Prevention, has not, so far, identified any further confirmed cases outside the initial transmission chain.
The index case arrived in Lagos on 20 July and died on 25 July. The 21-day incubation period has lapsed. All 12 cases were confirmed in a WHO-approved laboratory.
The intensity of the search and monitoring effort raises cautious optimism that further spread of the virus in Nigeria can be stopped. The search for additional cases continues, as does the current high level of vigilance.
The outbreak in Guinea, where the virus made its first appearance in west Africa last December, is less alarming than in Liberia and Sierra Leone.
Public awareness of the facts about Ebola is higher there than in the other affected countries. Innovative solutions are being found. For example, respected community leaders have been used to secure the cooperation of 26 villages that were highly resistant to outside help.
The opening of these villages has resulted in a surge of reported cases. These are cases that were previously concealed; their reporting should not be interpreted as a sudden upsurge in Guinea’s outbreak.
However, the outbreak is not under control. As recent experience shows, progress is fragile, with a real risk that the outbreak could experience another flare-up. A case in a previously unaffected area was reported last week, indicating continuing spread to new areas.