Rio de Janeiro Brazil South America
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The Centers for Disease Control and Prevention has issued a Level 2 alert in multiple states of Brazil due to a large, ongoing outbreak of yellow fever.

A Level 2 alert means travelers should take extra precautions before going to infected areas, such as getting vaccinated against certain diseases.

According to the CDC, since the end of 2017, yellow fever has been reported in the states of Rio de Janeiro, Minas Gerais, and São Paulo, including areas close to the city. The organization strongly recommends travelers and locals be vaccinated before going to any of these areas.

The CDC goes into more detail for international travelers who have already visited Brazil in early 2018, especially those who went to the island of Ilha Grande in the state of Rio de Janeiro. “Since early 2018, a number of unvaccinated travelers to Brazil contracted yellow fever...Several have died. None were from the United States,” it says on the CDC website.

If you are unvaccinated, the organization suggests avoiding travel to these areas. If you plan on taking a trip to Brazil any time soon, it’s best to plan ahead, as there are few clinics in the U.S. that offer the yellow fever vaccine.

Yellow fever is a virus that is commonly spread by mosquitoes. Symptoms include a fever, chills, fatigue, aching — especially in the knees and back — pain in the abdomen and muscles, and loss of appetite. It takes about three to six days before symptoms begin to appear after infection.

Severe cases can also include bleeding, red or yellow eyes and skin, delirium, headaches and vomiting. About 20 to 50 percent of severe cases are fatal, according to the CDC. There is no specific treatment for it other than hospitalization and treatment for visible symptoms.

More information on the outbreak, including a map of affected areas, can be found on the CDC website.