Lassa Fever in Nigeria

Warning - Level 3, Avoid Nonessential Travel
Alert - Level 2, Practice Enhanced Precautions
Watch - Level 1, Practice Usual Precautions

Key Points

  • Nigerian health officials have declared an outbreak of Lassa fever in Nigeria.
  • Lassa fever is a disease that is spread primarily by rats.
  • Travelers to Nigeria should avoid contact with rats, especially rat urine and feces, and keep their accommodations or campsites clean.
What is Lassa fever?

Lassa fever is a viral illness that occurs in West Africa. It is spread through contact with infected rodents or their droppings, or through close contact with a person who is sick with Lassa fever. It usually causes mild symptoms, including slight fever, weakness, and headache. However, in some people it can cause more serious symptoms, like bleeding in the gums, eyes, or nose; difficulty breathing; repeated vomiting; facial swelling; pain in the chest, back, and abdomen; shock; and even death.

What is the current situation?

The Nigeria Center for Disease Control has declared an outbreak of Lassa fever in Nigeria due to an increase in the number of cases reported across the country since the beginning of the year. Cases have been identified in several states. Most cases have been found in Edo and Ondo states.

How is Lassa fever virus spread?

Lassa fever is spread primarily by rats. Rats that carry the Lassa fever virus live in homes and areas where food is stored. People usually become ill with Lassa fever after accidentally eating or breathing in rat droppings or urine. This can happen through touching objects or eating food contaminated with rat droppings or urine, or after cleaning activities like sweeping. People who prepare or eat infected rats for food can also become ill with Lassa fever. Lassa fever may also spread when a person comes into contact with an infected person’s blood, tissue, or body fluids, especially when that person is seriously ill. 

What can travelers do to prevent Lassa fever?

Travelers to Nigeria should avoid contact with rats, especially rat urine and feces, and take precautions to keep their accommodations clean and free of rodents. . If you need to clean up after rodents, take the proper steps to avoid getting sick. Travelers should also wash hands often, and avoid contact with people who are sick.

Travelers who develop fever or other serious symptoms of Lassa fever during or after their trip should see a doctor right away. They should tell the doctor where they traveled in Nigeria and whether they had contact with a rodent or sick person. 

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