All you need to know about Lassa fever

Lassa fever is an acute viral infection caused by the Lassa virus.

Nigerians must take special care as Lassa fever is common to West Africa and it is an endemic disease in Nigeria.

The United States Centers for Control and Prevention states that the viral disease was first discovered in 1969 when two missionary nurses died in a village in Nigeria.

The agency states that the virus is named after the town in Nigeria where the first cases occurred.

There is an outbreak of Lassa fever in the country which has killed 43 people and it will be advisable for people to know its symptoms.

Symptoms

As in Ebola, the symptoms of Lassa fever occur one to three weeks after the patient comes into contact with the virus. Its general symptoms may include general malaise, weakness, and headache in mild cases but quickly adds that when untreated, the infection may progress to respiratory distress, bleeding in the gums, repeated vomiting, facial swelling, pain in the chest, back and abdomen as well as shock.

Neurological problems such as hearing loss, tremours, and encephalitis are symptoms of severe cases and if left untreated, death may occur within two weeks after symptom onset due to multi-organ failure in an infected person.

The most common complication of Lassa fever is deafness. Various degrees of deafness occur in approximately one-third of infections, and in many cases hearing loss is permanent. As far as is known, severity of the disease does not affect this complication: deafness may develop in mild as well as in severe cases.

Death usually occurs within 14 days of onset in severe cases. The disease is worse in pregnant women and nursing mothers.

Prevention

Preventing Lassa fever is first about knowing the source.

The disease is spread by exposure to and eating of food contaminated with rat dropping or urine.

The reservoir, or host, of Lassa virus is a rodent known as the multimammate rat of the genus Mastomys. It is not certain which species of Mastomys are associated with Lassa; however, at least two species carry the virus in some countries.

It is also spread by direct contact with the blood, urine, faeces or other bodily secretions of a person with Lassa fever. In short, those who contract this virus must have touched or eaten something that had been touched by an infected rat

Humans usually become infected with Lassa virus from exposure to urine or faeces of infected Mastomysrats. Lassa virus may also be spread between humans through direct contact with the blood, urine, faeces, or other bodily secretions of a person infected with Lassa fever.

There is no scientific evidence supporting airborne spread between humans.

Person-to-person transmission occurs in both community and health-care settings, where the virus may be spread by contaminated medical equipment, such as re-used needles.

Sexual transmission of Lassa virus has been reported.

Lassa fever occurs in all age groups and both sexes.

Persons at greatest risk are those living in rural areas where Mastomys are usually found, especially in communities with poor sanitation or crowded living conditions.