Serologic Survey among Hospital and Health Center Workers during the Ebola Hemorrhagic Fever Outbreak in Kikwit, Democratic Republic of the Congo, 1995

Abstract

From May to July 1995, a serologic and interview survey was conducted to describe Ebola hemorrhagic fever (EHF) among personnel working in 5 hospitals and 26 health care centers in and around Kikwit, Democratic Republic of the Congo. Job-specific attack rates estimated for Kikwit General Hospital, the epicenter of the EHF epidemic, were 31% for physicians, 11% for technicians/room attendants, 10% for nurses, and 4% for other workers. Among 402 workers who did not meet the EHF case definition, 12 had borderline positive antibody test results; subsequent specimens from 4 of these tested negative. Although an old infection with persistent Ebola antibody production or a recent atypical or asymptomatic infection cannot be ruled out, if they occur at all, they appear to be rare. This survey demonstrated that opportunities for transmission of Ebola virus to personnel in health facilities existed in Kikwit because blood and body fluid precautions were not being universally followed.

The 1995 Kikwit Ebola outbreak: lessons hospitals and physicians can apply to future viral epidemics

“…In late April/early May, additional health warnings were initiated after several health care providers at Kikwit General Hospital died. The deaths were traced back to a laboratory technician, who had undergone an operation at the facility for what was initially thought to be a surgical abdomen [2,5,6,9]. After some of the hospital staff involved in the operation and their family members developed Ebola, general panic occurred in the city.…”

“…After May 11, with the implementation of better disease isolation and barrier protective measures, only three new cases were reported in health care providers and Red Cross volunteers. Of the 316 suspected cases of Ebola identified during the 7-month outbreak, 252 people died [6,9,18,21]. Overall, 20-25% of the victims were health care workers [6,10,18].…”

“…Overall, 20-25% of the victims were health care workers [6,10,18]. Of the hospital staff infected, physicians had the highest rate of infection at 31% (4/13), followed by technicians/room attendants at 11% (7/62) and nurses at 10% (22/212) [9].…”

Viral Hemorrhagic Fevers: Differentiation of Natural Disease from Act of Bioterrorism

“…Asymptomatic or minimally symptomatic infections have, however, been suggested by serosurveys after Ebola virus outbreaks. A study using an ELISA method after a 1995 Zaire Ebola outbreak suggested there were other outcomes besides death or severe disease after infection [37,38]. Serum collected from close contacts of subjects after an Ebola outbreak in Gabon contained high levels of both circulating cytokines and Ebolaspecific antibody, further suggesting infection may occur without overt disease [39].…”

Ebola Virus Ecology

“…The Cameroon forest is also on the same latitude as southern Sudan, where the lessvirulent Sudan strain of Ebola virus circulates. We do know that some humans with high-titer antibody to Ebola virus survive infection during known outbreaks or single infections [17][18][19][20][21][22]. The Cameroon chimpanzees might, therefore, be survivors of an unknown local or regional epizootic.…”