Lassa hemorrhagic fever is a contagious viral disease caused by the Lassa virus. In its acute form, it is characterized by malaise, fever, vomiting, muscle pain and headache, symptoms that are also associated with malaria and typhoid fever. With time, however, bleeding from the orifices begins, comparing it to Ebola, which is also a viral hemorrhagic fever. This disease leads to low-grade deaths occurring within two weeks of symptomatic disease and has no known vaccine. Lassa fever was first discovered in 1969 in West Africa, particularly in the state of Borno in Nigeria. Since then, infections have been noted in other West African nations such as Ghana, Liberia, Guinnea and Sierra Leone. THE’ The current epidemic of Lassa fever is considered surprising, due to its more rapid spread than normal, which is by far the cause of many deaths, including the death of medical personnel deployed to offer assistance to the victims. It is also characterized by a high mortality rate of around 22%.
Etiology of Lassa Fever
Rodents, particularly native multi-family mice, are implicated in the initiation and spread of this disease. They are the carriers of the Lassa virus that belongs to the wrapped bi-segmented single-stranded RNA viruses, collectively known as Arenaviridae. These rats expel the virus into their urine and feces during their lifetime. This, combined with its high percentage of descent, makes the exposure massive. Humans are infected when they come into contact with the excretory products of rats through the fecal-oral or inhalation route and from there the horizontal diffusion begins through contact with the skin and contact with infected bodily fluids. Poor hygiene is implicated both in the initiation and in the spread of the disease.
Signs and symptoms associated with Lassa Fever
Lassa fever has been known to take an uncomplicated course, which represents almost 80% cases, or complicated. It is the complicated course of Lassa fever that leads to fatal fever which is an important manifestation. This disease affects four major organ systems. The most commonly affected is the gastrointestinal system, in which signs and symptoms are vomiting, diarrhea, nausea, constipation and hepatitis. Lowered blood pressure, increased heart rate, high blood pressure and carditis are the main signs of the cardiovascular system. With the respiratory system, dyspnea and chest pain are the cardinal signs. In patients whose nervous system has been affected by Lassa fever, they present with meningitis, convulsions and hearing defects which are thought to be reduced over time.
To properly manage Lassa fever, a correct diagnosis is very vital. Laboratory tests are used to distinguish the disease from others who are believed to have similar signs and symptoms. Cell cultures are used to verify the presence of the Lassa virus, the polymerase chain reaction for viral RNA and the ELISA test to verify the presence of antibodies produced against viral RNA. Blood tests show lymphopenia and thrombocytopenia in infected people. High aspartate aminotransferase is diagnostic, as is the presence of the virus in the cerebrospinal fluid.
The treatment of Lassa fever begins with isolation. Ribavirin which has both an oral and intravenous formulation has been shown to be effective when applied synergistically with blood transfusion and fluid replacement therapy. This fever has a generally good prognosis if treated early, with being poorer in a pregnant woman whose mortality rate is 80%.
Considering that there is no known vaccine, the Center for Disease Control recommends these preventive measures; rodent control, use of personal protective equipment in the management of infected people and adequate hygiene.