Sometimes ago, I received a call from some media consultants that they would like to come and interview me on Lassa fever. And my reaction was wow, Lassa fever again! Why Lassa fever? There is a possible resurgence of the fever in Nigeria. We even play “politics” with our lives.

Lassa fever had been with us so if there is resurgence now, we have ourselves to blame. This is because, more than anything, Lassa fever is primarily a disease of hygiene. How clean is our environment? What is our personal hygiene? What do we feed on? What type of health policies do we have, and how functional are they? Our problem is Nigeria is more of a problem of implementation.

Lassa fever is caused by a single-stranded RNA virus that is animal borne (zoonotic). It can cause a potentially fatal illness that can rapidly spread.  The virus is spread by a particular type of rat known as the 'multimammate rat'(Mastomys natalensis) that lives in large numbers in west, central, and east Africa.

While we are what we eat, our living conditions have direct impact on our health. People can get Lassa fever, also known as Lassa haemorrhagic fever (LHF) through contact with the urine or droppings of an infected rat; catching and preparing infected rats as food; inhaling tiny particles in the air contaminated with infected rat urine or droppings; and rarely, direct contact with a sick person’s blood or body fluids, through mucous membranes, like eyes, nose, or mouth. However, It should be noted that people with Lassa fever are not believed to be contagious before they have symptoms. Lassa fever is not spread through casual contact (like hugging, shaking hands, or sitting near someone).
Once infected, "multimammate rat" (Mastomys natalensis), the reservoir or host of Lassa virus, is able to excrete virus in urine for an extended time period, maybe for the rest of its life. The rodents breed frequently, produce large numbers of offspring. Also they readily colonize human homes and areas where food is stored.

According to Centre for Disease Control and Prevention (CDC), “Transmission of Lassa virus to humans occurs most commonly through ingestion or inhalation. Mastomys rodents shed the virus in urine and droppings and direct contact with these materials, through touching soiled objects, eating contaminated food, or exposure to open cuts or sores, can lead to infection. Because Mastomys rodents often live in and around homes and scavenge on leftover human food items or poorly stored food, direct contact transmission is common. Mastomys rodents are sometimes consumed as a food source and infection may occur when such infected rodents are caught and prepared. Contact with the virus may also occur when a person inhales tiny particles in the air contaminated with infected rodent excretions. This aerosol or airborne transmission may occur during cleaning activities, such as sweeping.
Direct contact with infected rodents is not the only way in which people are infected; person-to-person transmission may occur after exposure to virus in the blood, tissue, secretions, or excretions of a Lassa virus-infected individual. Person-to-person transmission is common in health care settings (called nosocomial transmission) where proper personal protective equipment (PPE) is not available or not used. Lassa virus may be spread in contaminated medical equipment, such as reused needles.”
The signs and symptoms of Lassa fever typically occur 1-3 weeks after the patient comes into contact with the virus. Mild symptoms include slight fever, general malaise and weakness, and headache. More serious symptoms include hemorrhaging (in gums, eyes, or nose, as examples), respiratory distress, repeated vomiting, facial swelling, pain in the chest, back, and abdomen, and shock. Neurological problems have also been described, including hearing loss, tremors, and encephalitis. Death may occur within two weeks after symptom onset due to multi-organ failure (CDC).
Lassa fever is most often diagnosed by using enzyme-linked immunosorbent serologic assays (ELISA), which detect IgM and IgG antibodies as well as Lassa antigen. Reverse transcription-polymerase chain reaction (RT-PCR) can be used in the early stage of disease. The virus itself may be cultured in 7 to 10 days, but this procedure should only be done in a high containment laboratory with good laboratory practices. Immunohistochemistry, performed on formalin-fixed tissue specimens, can be used to make a post-mortem diagnosis.
Because prevention is better than treatment and cure, there is need for efficient and effective prevention of Lassa fever. “Primary transmission of the Lassa virus from its host to humans can be prevented by avoiding contact with Mastomys rodents, especially in the geographic regions where outbreaks occur. Putting food away in rodent-proof containers and keeping the home clean help to discourage rodents from entering homes. Using these rodents as a food source is not recommended. Trapping in and around homes can help reduce rodent populations.
When caring for patients with Lassa fever, further transmission of the disease through person-to-person contact or nosocomial routes can be avoided by taking preventive precautions against contact with patient secretions (called VHF isolation precautions or barrier nursing methods). Such precautions include wearing protective clothing, such as masks, gloves, gowns, and goggles; using infection control measures, such as complete equipment sterilization; and isolating infected patients from contact with unprotected persons until the disease has run its course.
Further, educating people in high-risk areas about ways to decrease rodent populations in their homes will aid in the control and prevention of Lassa fever. Other challenges include developing more rapid diagnostic tests and increasing the availability of the only known drug treatment, ribavirin. Research is presently under way to develop a vaccine for Lassa fever.” (CDC)
Above all, we should endeavour to improve our living conditions, make the environment conducive for disease prevention and health promotion while calling on the government to be more responsible and responsive. The poverty level is too high – and a combination of hunger and poverty can force people to scavenge and eat anything including shit, and if the situation is not remedied on time, cannibalism may become inevitable!