A teenager gets a vaccine against yellow fever at an outpatient clinic in Sao Paulo, Brazil. (Miguel Schincariol/AFP/Getty Images)

Travelers headed to Brazil should add one more item to their trip prep list: Make an appointment for a yellow fever vaccination.

The Centers for Disease Control and Prevention recently raised the level of concern for Brazil, in response to a yellow fever outbreak. The agency expanded its warning to travelers after a number of unvaccinated tourists contracted the mosquito-borne virus in newly identified hot spots. For example, several people became ill on Ilha Grande, a beachy island in the Rio de Janeiro state, and in the forested outskirts of Sao Paulo. The agency and travel medical specialists are urging vacationers to get vaccinated — or skip the trip.

“If you are going for tourism, you should definitely get the vaccine,” said Ernesto Marques, an infectious disease epidemiologist and vaccine researcher with the University of Pittsburgh Graduate School of Public Health and the Oswaldo Cruz Foundation in Brazil.

During a phone briefing Friday, Marty Cetron, director of CDC’s Division of Global Migration and Quarantine, said, “Don’t travel to these hot spots without the vaccination.”

The CDC heightened its warning to Level 2: Practice Enhanced Precautions and flagged a new swath of affected areas on its color-coded map. A peach hue now covers several east coast destinations, including Espirito Santo state; Sao Paulo state and city and coastal islands; Rio de Janeiro state, including the city of Rio and all coastal islands; and several cities in Bahia state. Only a small section along the upper east coast and near the southern border with Uruguay are considered fever-free.

More generally, Marques pointed out remote beaches, farms, forests, ecotourist retreats and the Atlantic Forest outside Sao Paulo and Rio as potentially hazardous zones.

In addition to the new areas of risk, CDC is alerting travelers to the intensity of the transmission. Typically, individuals experience such flulike symptoms as fever, chills and an achy head, back and muscles. However, 15 percent of patients suffer life-threatening symptoms, such as shock and organ failure, and many never recover. Between July 1 and Jan. 14, the World Health Organization documented 35 cases of yellow fever in Brazil, including 20 deaths. The number of reports tripled in the states of Sao Paulo (20, with 11 deaths) and Minas Gerais (11, with seven deaths).

To stay healthy, CDC recommends the vaccine to travelers who have never received it before or were last poked more than 10 years ago. Marques said the vaccine’s potency diminishes over time. Schedule an appointment for at least 10 days before your departure date.

Previously, travel clinics and physicians administered the vaccine, YF-Vax, which is licensed in the United States. However, because of high demand, the supply has run dry and will not become available until the end of the year. As an alternative, CDC suggests Stamaril, which travelers can find at about 250 locations around the country. An online locator map provided by CDC lists five locations in Washington, including the Washington Travel Clinic, Travelers Medical Service and Georgetown University Hospital. Prices vary. For instance, the Washington Travel Clinic charges a $40 visit fee, plus $190 for the vaccination; Travelers Medical Service costs slightly more, at $55 for the office fee and $190 for the shot.

For an extra layer of protection, stock up on insect repellent and wear long-sleeve shirts and pants for outdoor excursions. Also, when booking your accommodations, make sure your room has such mosquito-deterring features as air-conditioning, screens and insecticide-treated bed nets.

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