Transmission of Ebola hemorrhagic fever: A study of risk factors in familymembers, Kikwit, Democratic Republic of the Congo, 1995

The surviving members of 27 households in which someone had been infected w ith Ebola virus were interviewed in order to define the modes of transmissi on of Ebola hemorrhagic fever (EHF). Of 173 household contacts of the prima ry cases, 28 (16%) developed EHF. All secondary cases had direct physical c ontact with the ill person (rate ratio [RR], undefined; P < .001), and amon g those with direct contact, exposure to body fluids conferred additional r isk (RR, 3.6; 95% confidence interval [CI], 1.9-6.8). After adjusting for d irect contact and exposure to body fluids, adult family members, those who touched the cadaver, and those who were exposed during the late hospital ph ase were at additional risk. None of the 78 household members who had no ph ysical contact with the case during the clinical illness were infected (upp er 95% CI, 4%). EHF is transmitted principally by direct physical contact w ith an ill person or their body fluids during the later stages of illness.