Lassa fever is one of the lethal viral haemorrhagic fevers, apart from Ebola, Dengue and some others. It’s predominantly a disease of West Africa that was first discovered in 1969 in a Nigerian town called Lassa where two missionary nurses died from the disease. Since then, there have been periodic epidemic outbreaks of the disease in different parts of Nigeria and the West African subcontinent. Furthermore, it is instructive to note that there is even an ongoing outbreak of this viral illness that has affected no less than 150 people in seven states of Nigeria namely Taraba, Kano, Rivers, Bauchi, Oyo, Niger and Nasarawa. This is according to Dr Abdulsalami Nasidi, Director of the Nigerian Centre for Disease Control in a recent interview with BBC Hausa. Sadder still, 7 people have since died from the disease in Taraba, Kano and Rivers states. Arguably, a low level of awareness on the part of the public is a major contributor to the rapid spread of this scourge.
In this light, this article seeks to enlighten you on general facts you need to know as far as Lassa virus is concerned.
- Lassa fever is a viral illness
It’s an acute viral illness caused by Lassa virus which was first discovered in Nigeria. Lassa virus is a single-stranded RNA virus that belongs to a family called Arenaviridae. The natural host or reservoir of this virus is a rodent known as the ‘multimammate’ rat that belongs to the mastomys genus. It’s been observed that mastomys rats breed very frequently and readily colonise homes, hence the easy spread of this zoonotic virus from infected rodents to unsuspecting humans.
- Lassa fever is quite common in West Africa
Lassa virus infections are common enough in West Africa to warrant public health concern. Averagely, about 300000 cases are recorded each year with 5000 deaths. Unfortunately, the present Lassa epidemic in Nigeria has already spanned 7 states and affected at least 150 people with 7 casualties already reported.
- How is Lassa virus spread to humans?
Humans can contract the virus when they come in contact, directly or indirectly with the urine and droppings from infected rats or by breathing in tiny particles from air that has been contaminated with rodent excretions. Some humans who eat infected rodents can equally contract the virus. Lastly, if adequate precautions are not taken, care givers who handle or treat infected persons can contract the virus from contaminated blood, tissues, secretions or excretions of such patients. However, it cannot be spread through casual skin-to-skin contacts, provided there are no cuts or bruises.
- Lassa fever usually produces symptoms
Lassa virus has an incubation period of 1 – 3 weeks following which signs and symptoms of the infection emerge. Initially, non-specific symptoms such as fever, sore throat, cough, back pain, abdominal pain or pain behind the chest wall may be felt as well as vomiting, diarrhoea and facial swelling. As the disease progresses, mucosal bleeding and bleeding from body orifices may follow.
Lassa fever can be treated
Provided the affected person presents early enough and prompt diagnosis of Lassa fever is made, an antiviral agent called Ribavirin has been shown to be quite effective in reducing morbidity and mortality from the disease. In addition to ribavirin administration, supportive treatment may also be given to maintain fluid and electrolyte balance as well as the blood pressure.
Untreated Lassa fever often results in death
It was estimated that 15 – 30% of patients who are admitted for Lassa fever end up dying from the illness. Moreover, death rates are even higher for pregnant women, especially those in the third trimester and their unborn babies. Sadly, mortality rates in the latter group sometimes approach 95%. Furthermore, up to one-third of Lassa fever survivors may suffer from varying degrees of hearing loss which may be permanent.
Lassa fever is better prevented
Prevention is better than cure. Since no vaccine has been developed yet for Lassa virus infection, people must employ every possible means to avoid contact with rodents and infected people. Our homes must be kept clean and rodent-free, foods should be stored in rodent-proof containers. Health care givers must practise barrier nursing methods such as isolation of infected patients and consistent use of face masks, gloves, gowns and goggles when attending to such patients.