ON LASSA FEVER:
Lassa Fever Epidemic is with us again. About ten states have reported about 91 cases with mortality of 40%. This necessitates this fact sheet on d disease for everyone.
Lassa Fever is an Acute Febrile disease caused by d Lassa virus belonging to d arena virus group. It was first described in d 50s & d virus was isolated in 1969 in Lassa, Nigeria.
Lassa Fever occurs more often in d dry season, rather than d rainy season.
D multimammate rat (Mastomys natalensis) is d reservoir host of Lassa fever.
Deafness is a common sequela in up to 1/3 of cases.
Case fatality rate varies from as low as 1%-25% to as high as 50%.
D death rates are particularly high for women in d third trimester of pregnancy & for fetuses, about 95% of which die in d uterus of infected pregnant mothers.
Cases have been reported January 2016 in Bauchi, Kano, Nassarawa, Niger, Rivers, Edo, Lagos, Taraba and FCT
Humans usually become infected from exposure to excreta of infected rats (Mastomys) via direct exposure to their excreta.
Lassa virus may also be spread b/w humans through direct contact with d blood, urine, faeces or other bodily secretions of a person with Lassa Fever.
There is no epidemiological evidence supporting airborne spread between humans.
Person-to-person transmission occurs in both community & health care settings where d virus may be spread by contaminated medical equipment such as re-used needles.
Sexual transmission of Lassa virus has been reported.
Incubation Period is usually 10 days but can range from 6-21 days.
a) Suspected case: Illnesses with onset of fever, with or without sore throat & at least one of d following signs: bloody diarrhea, bleeding from gums, bleeding into skin (purpura), bleeding into eyes & urine.
b) Confirmed case: A suspected case with laboratory confirmation (positive IgM antibody or viral isolation) or epidemiological link to confirm cases or outbreaks.