Context

• One of the three persons diagnosed with Lassa fever in the UK died recently.

What is Lassa fever and how does it spread?

• The Lassa fever-causing virus is found in West Africa and was first discovered in 1969 in Lassa, Nigeria. 
• The fever is spread by rats and is primarily found in countries in West Africa including Sierra Leone, Liberia, Guinea, and Nigeria where it is endemic.
• A person can become infected if they come in contact with household items of food that is contaminated with the urine or feces of an infected rat. 
• It can also be spread, though rarely, if a person comes in contact with a sick person’s infected bodily fluids or through mucous membranes such as the eyes, nose or the mouth. Person-to-person transmission is more common in healthcare settings.

Symptoms

• Symptoms typically appear 1-3 weeks after exposure. Mild symptoms include slight fever, fatigue, weakness and headache and more serious symptoms include bleeding, difficulty breathing, vomiting, facial swelling, pain in the chest, back, and abdomen and shock.
• Death can occur from two weeks of the onset of symptoms, usually as a result of multi-organ failure. 
• The death rate associated with this disease is low, at around one per cent. But the death rate is higher for certain individuals, such as pregnant women in their third trimester.
• The best way to avoid getting infected is to avoid contact with rats. This means avoiding contact with rats not only in places where the disease is endemic, but also maintaining hygiene in other areas to prevent rats from entering the house, keeping food in rat-proof containers and laying down rat traps.

Reference:

1. https://indianexpress.com/article/explained/explained-what-is-lassa-fever-and-what-are-its-symptoms-7773656/