LASSA FEVER

Lassa fever is an acute viral illness that occurs in west Africa. It was discovered in 1969 when two missionary nurses died in Nigeria, West Africa. The cause of it (Lassa Fever) was found to be Lassa Virus, named after the town in Nigeria were the first cases started.

          It is an endemic (constantly present) in the West African Countries like Guinea, Sierra Leone, Liberia as well as Nigeria this is because the rodent species which carry the virus are found throughout West Africa.

          Replication for Fever Virus is very rapid also demonstrating temporal control in replication. There are two genome segments. The first replication step is transcription of RNA copies of negative or minus-sense genome. This ensures an adequate supply of viral proteins for subsequent steps of replication, as proteins known as N and L are translated from the MRNA. The positive or plus-sense genome then makes viral complementary RNA (vc RNA) copies of itself, which are sense. The VcRNA is a template for producing – sense progeny but mRNA is also synthesized from it. The MRNA synthesized from VcRNA are translated to make the G (Spike) proteins and Z proteins. Thus with this temporal control, the spike proteins which are on the outside of the virus particle, are produced last, making the infection more difficult for the host immune system to detect.

It is very difficult to know when one contact this disease but the non specific symptoms include fever, facial swelling and muscle fatigue, as well as conjunctivitis and mucosal bleeding.

Lassa fever is treated with Ribauirin, an antiviral drug, it has been shown to be most effective when given early in the course of the illness. Again patients should also receive supportive cure consisting of maintenance of appropriate fluid and electrolyte balance, oxygenation and blood pressure, as well as treatment of any complicating infections.