The Lassa fever was discovered in 1969.
For a world grappling with the coronavirus disease (Covid-19), the news of a fresh virus has spared concern. The Lassa fever has claimed three lives in the United Kingdom, and the country's health officials have said that it has “pandemic potential”. Eight cases of the Lassa fever have been reported in the UK since the 1980s, with the last two coming in 2009.
What is Lassa fever?
According to United States' Centers for Disease Control (CDC), it is an animal-borne, or zoonotic, acute viral illness.
The haemorrhagic illness is caused by Lassa virus, a member of the arenavirus family of viruses.
How does it infect the humans?
According to World Health Organization (WHO), humans usually become infected with Lassa virus through exposure to food or household items contaminated with urine or faeces of infected Mastomys rats. The disease is endemic in the rodent population in parts of West Africa.
Person-to-person infections and laboratory transmission can also occur, particularly in health care settings in the absence of adequate infection prevention and control measures, according to further information about the disease from WHO.
When was the first case of Lassa virus reported?
The illness was discovered in 1969 and is named after the town in Nigeria where the first cases occurred.
According to CDC, an estimated 100,000 to 300,000 infections of Lassa fever occur annually, with approximately 5,000 deaths.
Signs and symptoms
The incubation period of Lassa fever ranges from 2-21 days. According to WHO, majority of Lassa fever symptoms are mild and undiagnosed.
It starts gradually with fever, general weakness and malaise. As the infection progresses, the patients may also experience headache, sore throat, muscle pain, chest pain, nausea, vomiting, diarrhoea, cough, and abdominal pain, according to WHO.
In severe cases facial swelling, fluid in the lung cavity, bleeding from the mouth, nose, vagina or gastrointestinal tract and low blood pressure may develop, the WHO further said, adding that death usually occurs within 14 days in fatal cases.
Due to varied and non-specific, the Lassa fever is hard to diagnose, especially early in the course of the disease. According to WHO, Lassa fever is difficult to distinguish from other viral haemorrhagic fevers such as Ebola virus disease, malaria, shigellosis, typhoid fever and yellow fever.
Ribavirin, an antiviral drug, has been used with success in Lassa fever patients, said the CDC. The drug has been shown to be most effective when given early in the course of the illness, it further said.
A supportive care is also advised by the CDC, consisting of maintenance of appropriate fluid and electrolyte balance, oxygenation and blood pressure.