Lassa fever, a viral hemorrhagic fever, is an acute disease which spans from one to four weeks. This illness is affecting several areas in West Africa. It was first portrayed around the year 1950s. Lassa fever virus that was causing the illness was fully identified in the year 1969. It is a virus of single strand RNA from the Arenaviridae virus family.
Lassa fever was widely known to be prevalent in areas of Liberia, sections of Nigeria, Sierra Leone, Guinea or Conarky. Although the disease is believed to certainly exist in other countries in the West Africa as well.
Symptoms of Lassa Fever
About eighty percent of the infections recorded showed little to no symptoms at all while the remaining percentage manifested a serious multi-system illness wherein the virus modifies a number of internal organs in the body like the kidneys, spleen and liver. The period of incubation of the Lassa fever begins at six to twelve days. The illness progresses slowly and starts with a fever followed by weakness of the body and malaise. Few days after that, a range of aches will follow, mostly in the abdominal area. Coughing, diarrhea, vomiting, nausea, chest pain, muscle pain, sore throat and headache are also displayed. In serious cases the pains may progress into swelling of the face, fluid presence in the lung cavity, bleeding from the gastrointestinal tract, vagina, nose or mouth accompanied with low blood pressure. There may be protein presence in the urine. In later stages of the illness, coma, disorientation, tremor, seizures and shock may ensue. Twenty-five percent of the patients lose their hearing, of which about half recover some of their auditory functions after one to three months. Gait disturbance and transient loss of hair may follow within the duration of recovery.
Certain studies showed that every year across West Africa, patients with Lassa fever amounts between 300,000 and 500,000 with 5000 mortality. Overall, the fatality rate of the case is one percent to fifteen percent among the number of patients hospitalized. Death commonly happens within fourteen days of the start of the fatal cases. Likewise, the illness can be pretty serious during late pregnancy.
Where does Lassa fever virus originate from
The virus comes from infected animals which mean that Lassa fever is considered a zoonotic disease. Humans who had contact with animals infected with the virus are infected with Lassa fever. The host of the virus or its animal reservoir is a rodent belonging to the genus Mastomys, another term for multimammate rat. The Mastomys are not affected nor do they become sick with the virus. The virus is expelled from the rodent’s body by urine of feces.
Lassa fever risk factors
The fever affects both men and women in all age groups and the virus are highly present at rural areas where these infected rodents are commonly found particularly on areas that have crowded occupants or poor sanitation. Workers in health care services are also at risk of being infected if they are not maintaining the practice of infection control and proper barrier nursing.
Exposure to the excreta of the infected rodents is the start of the development of the Lassa virus. A person can also be infected with direct contact to the secretions of an infected individual. There is no solid evidence pertaining to the virus being air-borne although strong cases note the person to person transmission. It is also noted that sexual contact can be a means to infect as well.
Diagnosis of Lassa fever
Clinical diagnosis of the Lassa virus can be quite difficult because its symptoms are not specified and varied particularly during the early stages of the development of the disease. It is also difficult to identify the Lassa fever apart from other illness that causes fever such as the malaria, yellow fever, typhoid fever and shigellosis. It requires thorough evaluations and tests to help pinpoint that the virus is causing the fever. These tests are available in laboratories and facilities that are highly specialized. The diagnosis of the Lassa fever is through detection of the anti-Lassa antibodies and Lassa antigen. Other virus isolation practices are applied as well.
Treatment and prevention of Lassa Fever
The ribavirin is an antiviral medicine that is effective against Lassa fever only when it is given to the patient on the early stages of the illness.
In order to prevent the Lassa fever from spreading, it is essential to practice good hygiene. It is imperative that the infected rodents be prevented from infesting the house or the surrounding area. In this regard, food and perishables that attract these rodents should be kept in tightly sealed containers, trash should be kept and properly disposed of far from the house, keeping the house clean and bringing in cats are some effective ways to drive away rats. Remember though, that it is not possible to completely eliminate them from the area.