What is Lassa fever?
Lassa fever is one of the viral haemorrhagic fevers. Viral haemorrhagic fevers, also known as VHF, are infections caused by viruses that have fever and bleeding as prominent symptoms at some point during their course. Examples of VHF are Lassa, Yellow and Ebola virus diseases, among others. Lassa fever is endemic in West Africa and is quite common in Nigeria. It occurs all year-round, but the frequency increases during the peak of the dry season.
how transmission from the rat to a human occurs?
There are primary and secondary means of transmission. Primary transmission occurs when a person comes in contact with the body fluid or droppings of the multimammate rat, which is the vector of the disease. This can occur through trying to kill these rats or bush rats for food or if your foodstuffs are not well stored, and these roddents eat from them or leave droppings on them; direct contact with urine, faeces, saliva or blood of infected rodents; contact with objects, household items or surfaces contaminated with urine, faeces, saliva or blood of infected rats; consumption of the rats, these are the major methods of transmission. Secondary transmission occurs when a person comes in contact with the body fluids or secretions of another infected person, like being a caregiver to such a person.
What are the major signs and symptoms?
The signs and symptoms are usually non-specific, being poorly differentiated from many of the febrile illnesses like malaria or gastrointestinal illnesses. It is also important to state that many people who come in contact with the virus may not develop symptoms.
Can the virus be transmitted sexually?Studies have shown that sexual transmission of the virus can occur. This occurs because of the persistence of the virus in vaginal and seminal fluids of infected patients for a duration of time even after apparent recovery. The virus has been detected in vaginal fluid up to three months, and in seminal fluid in some cases more than six months after these patients recovered with implications for transmission of the virus. This is why confirmed infected cases are always advised to use protection during sexual intercourse for some months afterward. Transmission can also occur from an infected pregnant woman to her child.
What is the prevalence rate in Nigeria?
Going by antibody seroprevalence, which estimates the number of people who have come in contact with the virus, prevalence has been found to be around 21 per cent.
Is there a vaccine against Lassa fever?Presently, no, but a couple of candidate vaccines are in the works.
What are the most effective ways to prevent infection in communities?
If one has an unexplained fever, with any of the above symptoms, or they have unexplained bleeding from any body orifice, they should avoid self-medication, drink plenty of fluids and present at a hospital for review. There are effective medications that can be used for treatment, especially if patients present early. Lassa fever infection can be prevented by practising proper hand hygiene at all times – before and after using a toilet, before and after cooking, after being in crowded places, after dealing with animals and at other times.
Also, it is important to maintain a clean environment at all times, properly dispose of waste, rat-proof our homes, keep our foodstuffs in covered containers and find a way to eliminate rats from your homes; possibly keep cats. One should avoid bushmeat for now and, if possible, reduce or avoid bush burning.
