Lassa fever outbreaks have recently occurred in some parts of Africa including Nigeria, making a pandemic-stricken world even more anxious. Caused by the Lassa virus, the disease has already claimed three lives in the United Kingdom.
Lassa fever is an animal-borne, or zoonotic, acute viral infection, according to the United States’ Centres for Disease Control (CDC). The virus can spread if a person comes in contact with the bodily fluids (blood, saliva, urine or semen) of an infected person. A rodent of the genus Mastomys, sometimes known as the “multimammate rat,” is the animal reservoir or host of the Lassa virus. Mastomys rats infected with the Lassa virus do not get sick, but the virus can be passed on through their urine and feces. The virus has also been called the ‘cousin’ of Ebola due to the similarities shared by both diseases.
The Lassa virus is spread by food and household objects contaminated with the urine or feces of infected rats, which can be found in a number of West African nations where the disease is endemic. The virus can also be passed from one person to another by infected bodily fluids. Secondary human-to-human transmission may occur, though to a lesser extent, by close contact with infected patients’ blood, saliva, organs, or other body fluids, particularly in healthcare settings, as per the WHO. There is no epidemiological evidence to suggest that the disease spreads through the air. Person-to-person transmission can occur in both health care and community settings, where infected medical supplies, such as re-used syringes, can spread the virus. The Lassa virus has also been linked to sexual transmission.
The majority of those who contract Lassa fever, according to the UK health ministry, will recover completely. Severe illness, on the other hand, can strike some people. Lassa fever is uncommon in the UK, and it is difficult to transfer between people, according to Dr. Susan Hopkins, UKHSA’s chief medical advisor, who also stated that the overall risk to the community is very low.
The incubation period of Lassa fever ranges from 6–21 days. When the disease is symptomatic, the onset is usually gradual, with fever, general weakness, and malaise as the first signs. Headache, sore throat, muscle discomfort, chest pain, nausea, vomiting, diarrhea, cough, and stomach pain may occur within a few days. Swelling of the face, fluid in the lungs, bleeding from the mouth, nose, vaginal or gastrointestinal tract and low blood pressure can all occur in severe cases.
The antiviral medicine ribavirin, according to the WHO, appears to be an effective cure for Lassa fever when given early in the course of clinical illness. Ribavirin’s use as a post-exposure prophylactic therapy for Lassa fever has not been proven.
Currently, there is no vaccination available to protect against Lassa fever.
