With transmissions between family members accounting for most infections during the 2014-2016 West Africa Ebola outbreak, the virus spread to other members in one out of three households that was home to an infected person, a study in one Sierra Leone community found. In half of those households experiencing transmissions, the initial case led to two or more infections.
The study examined histories gathered from 94 households that were home to survivors who had been treated at the one of the local Ebola treatment centers. Altogether those households held 937 people, 427 people of whom had been infected during the outbreak, and 238 of whom had died. Households ranged in size from one person to 27, with as many as 21 people becoming infected in a single household. In all of the 25 households in which the first person to become infected died at home, other household members subsequently became infected, researchers found. The virus was less likely to spread in households with members working in healthcare, and household transmissions declined later in the epidemic, indicating that as the outbreak continued, knowledge of how the virus spread enabled household members to avoid infection. In addition, the authors note, household transmissions decreased as the numbers of beds at Ebola treatment centers increased.
The researchers note that as household transmissions exceed transmissions in healthcare settings and funerals, more needs to be known about factors increasing the risks transmissions in homes. The study, reported in The Journal of Infectious Diseases, was led by Judith R. Glynn of the London School of Hygiene and Tropical Medicine.