What is Lassa Fever, symptoms and more? Is this a sign of the new pandemic era?

New Delhi, Feb 15: As the Omicron variant of Covid-19 recede, a new virus is sparking concerns in the United Kingdom. At least three cases of Lassa Fever have been confirmed in the UK, of which one has died.

According to reports, all three cases of the virus have a travel history from West Africa.

There have been no cases detected in India so far and experts are watching the situation. The World Heath Organisation is also monitoring the situation in the UK.

Dr Anthony Fauci, chief medical advisor to the President of the United States, had warned in August 2020 that the world is entering a "new pandemic era".

But, as the acute phase of one epidemic finally appears to wane - at least for now - Lassa's re-emergence in Britain is a stark reminder that the world is entering a "new pandemic era", as

But the next pandemic may not look like Covid-19. Alongside Lassa fever, the WHO's list of priority pathogens with pandemic potential includes Crimean-Congo haemorrhagic fever (CCHF), Ebola and Marburg.

What is Lassa Fever?

Lassa fever is an animal-borne, or zoonotic, acute viral illness. It is endemic in parts of West Africa including Sierra Leone, Liberia, Guinea and Nigeria. Neighboring countries are also at risk, as the animal vector for Lassa virus, the "multimammate rat" (Mastomys natalensis) is distributed throughout the region.

The illness was discovered in 1969 and is named after the town in Nigeria where the first cases occurred.

An estimated 100,000 to 300,000 infections of Lassa fever occur annually, with approximately 5,000 deaths. Surveillance for Lassa fever is not standardized; therefore, these estimates are crude. In some areas of Sierra Leone and Liberia, it is known that 10-16% of people admitted to hospitals annually have Lassa fever, demonstrating the serious impact the disease has on the region.

Transmission

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.

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.

Casual contact (including skin-to-skin contact without exchange of body fluids) does not spread Lassa virus. 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.

Signs and Symptoms

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.

Serious symptoms including

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.

The most common complication of Lassa fever is deafness. Various degrees of deafness occur in approximately one-third of infections, and in many cases hearing loss is permanent. As far as is known, severity of the disease does not affect this complication: deafness may develop in mild as well as in severe cases.

Because the symptoms of Lassa fever are so varied and nonspecific, clinical diagnosis is often difficult.

Treatment

Ribavirin, an antiviral drug, has been used with success in Lassa fever patients. It has been shown to be most effective when given early in the course of the illness. Patients should also receive supportive care consisting of maintenance of appropriate fluid and electrolyte balance, oxygenation and blood pressure, as well as treatment of any other complicating infections.

Maintaining hygiene and cleanliness in the house and elsewhere is also important. Preventing rats from entering the house and keeping food in rat-proof containers can be a great step to protect yourself from the Lassa virus.