Investigation and Epidemiological Surveillance of Contact persons during an Outbreak of Lassa Fever
METHODS: We reviewed hospital records from July-August 2012, interviewed health workers and conducted active case search and environmental assessment including rodents search. Blood samples were obtained from high risk contacts; including household contacts, bakery staff and health workers for serological tests. A suspected case was defined as any person resident in Ibadan or reported sick at the health facility between July and August 2012 with fever >38◦C (101◦F) and one or more of following: bleeding, chest pain, and not responding to appropriate anti-malarial or antibiotics treatment within 24-72hours of treatment. A confirmed case was a suspected case with positive ELISA IgM.
RESULTS: Two cases were identified; one confirmed case and a suspected case with one death (case fatality rate of 50%). There was no epidemiological linkage between the two cases, and serological test for all high risk contacts were negative. There was evidence of rat infestation in the home and bakery surroundings. There were no standardized protocols for the case detection and management of LF in all health facilities visited.
CONCLUSIONS: The possible mode of spread was rodent to human. We conducted public health education and assessed health facilities epidemic preparedness response capacity. We recommended further research into prevalence of infected Mastomys rat in this locality, and training of health workers on early detection and case management.