Lessons learned about pneumonic plague diagnosis from two outbreaks, Democratic Republic of the Congo.

Pneumonic plague is a highly transmissible infectious disease for which fatality rates can be high if untreated; it is considered extremely lethal. Without prompt diagnosis and treatment, disease management can be problematic. In the Democratic Republic of the Congo, 2 outbreaks of pneumonic plague occurred during 2005 and 2006. In 2005, because of limitations in laboratory capabilities, etiology was confirmed only through retrospective serologic studies. This prompted modifications in diagnostic strategies, resulting in isolation of Yersinia pestis during the second outbreak. Results from these outbreaks demonstrate the utility of a rapid diagnostic test detecting F1 antigen for initial diagnosis and public health management, as well as the need for specialized sampling kits and trained personnel for quality specimen collection and appropriate specimen handling and preservation for plague confirmation and Y. pestis isolation. Efficient frontline management and a streamlined diagnostic strategy are essential for confirming plague, especially in remote areas.

A limited outbreak of Ebola haemorrhagic fever in Etoumbi, Republic of Congo, 2005.

Ebolavirus has caused highly lethal outbreaks of haemorrhagic fever in the Congo basin. The 2005 outbreak in the Republic of Congo occurred in the Etoumbi district of Cuvette Ouest Department between April and May. The two index cases were infected while poaching. The sanitary response consisted of active surveillance and contact tracing, public awareness campaigns and community mobilization, case management and safe burial practices, and laboratory confirmation. Twelve cases and ten deaths were reported (lethality 83%). A transmission tree was constructed from a sample collected by a medical team. This outbreak was remarkable by its short duration and limited size. Increased awareness among these previously affected populations and the rapid response of the healthcare system probably contributed to its extinction.

Lessons learned during active epidemiological surveillance of Ebola and Marburg viral hemorrhagic fever epidemics in Africa.

OBJECTIVE: To review epidemiological surveillance approaches used during Ebola and Marburg hemorrhagic fever epidemics in Africa in the past fifteen years. Overall, 26 hemorrhagic epidemic outbreaks have been registered in 12 countries; 18 caused by the Ebola virus and eight by the Marburg virus. About 2551 cases have been reported, among which 268 were health workers (9,3%). METHODS: Based on articles and epidemic management reports, this review analyses surveillance approaches, route of introduction of the virus into the population (urban and rural), the collaboration between the human health sector and the wildlife sector and factors that have affected epidemic management. FINDINGS: Several factors affecting the epidemiological surveillance during Ebola and Marburg viruses hemorrhagic epidemics have been observed. During epidemics in rural settings, outbreak investigations have shown multiple introductions of the virus into the human population through wildlife. In contrast, during epidemics in urban settings a single introduction of the virus in the community was responsible for the epidemic. Active surveillance is key to containing outbreaks of Ebola and Marburg viruses CONCLUSIONS: Collaboration with those in charge of the conservation of wildlife is essential for the early detection of viral hemorrhagic fever epidemics. Hemorrhagic fever epidemics caused by Ebola and Marburg viruses are occurring more and more frequently in Sub-Saharan Africa and only an adapted epidemiological surveillance system will allow for early detection and effective response.