Lassa Fever: another infectious menace

Nigeria is presently suffering from another Lassa fever epidemic. This was confirmed in the statement of the Minister of Health of the Federation in which he said; ""There has been an upsurge in the reported cases of Lassa fever since the beginning of this year; especially in the Federal Capital Territory and its environs. Within two weeks; 12 cases with five deaths due to the disease were recorded. 25 contacts are confirmed by laboratory investigations to have been infected; including 4 health staff working in the National Hospital; Abuja.""1 Lassa fever is an acute viral haemorrhagic fever first described in 1969 in the town of Lassa in Borno state; Nigeria.2 It is endemic in West African countries; and causes 300;000 cases annually with 5000 deaths.3 Lassa fever epidemics occur in Nigeria; Liberia; Sierra Leone; Guinea and the Central African Republic.4 Lassa virus; the agent of the disease is a member of the Arenaviridae family. The virus is pleomorphic with single-stranded and bisegmented RNA genome.3 Its primary host is Natal Multimammate Mouse (Mastomys natalensis). Transmission to man occurs via exposure to the rat excrement through respiratory or gastrointestinal tracts5; exposure of broken skin or mucus membrane to infected material; direct contact; sexually and transplacentally. The prevalence of antibodies to the virus is 8-229 in Sierra Leone; 4-55in Guinea;12 and 21in Nigeria.13 The disease is mild or asymptomatic in 80of infected people; but 20have a severe multisystemic disease. Clinical features are difficult to differentiate from that of other viral haemorrhagic fevers and common febrile illness such as Malaria; Typhoid fever and so on. Definitive diagnosis is by viral isolation; Antigen and Antibody detection and Reverse Transcriptase PCR. Treatment is with Ribavirin; an antiviral agent. No vaccine is currently available. Prevention is by keeping rats away from homes

Lassa fever in West African sub-region: an overview.

Lassa fever is an acute viral zoonotic illness caused by Lassa virus, an arenavirus known to be responsible for a severe haemorrhagic fever characterised by fever, muscle aches, sore throat, nausea, vomiting and, chest and abdominal pain. The virus exhibits persistent, asymptomatic infection with profuse urinary virus excretion in the ubiquitous rodent vector, Mastomys natalensis. Lassa fever is endemic in West Africa and has been reported from Sierra Leone, Guinea, Liberia, and Nigeria. Some studies indicate that 300,000 to 500,000 cases of Lassa fever and 5000 deaths occur yearly across West Africa. Studies reported in English, that investigated Lassa fever with reference to West Africa were identified using the Medline Entrez-PubMed search and were used for this review. The scarcity of resources available for health care delivery system and the political instability that characterise the West African countries would continue to impede efforts for the control of Lassa fever in the sub-region. There is need for adequate training of health care workers regarding diagnostics, intensive care of patients under isolation, contact tracing, adequate precautionary measures in handling infectious laboratory specimens, control of the vector as well as care and disposal of infectious waste.