Brazil: Chikungunya in Rio de Janeiro state /update 1

Event

Transmission rates of the mosquito-borne disease chikungunya are high in the state of Rio de Janeiro. A total of 36,102 cases, including 16 fatalities, were reported between January 1 and November 13. During the same period, 2223 cases of the Zika virus and 13,886 cases of dengue fever were also reported in the state. These three diseases are all transmitted by the same type of mosquito, the Aedes aegypti. 

Context

Symptoms of chikungunya include high fever, joint and muscle pain, rash, headache, nausea, and fatigue. The virus is rarely fatal but lingering joint pain can last for several weeks, even months, after the initial recovery. No vaccine for the virus is currently available.

Symptoms of dengue fever include fever, headache, muscle and joint pain, fatigue, nausea, and rashes. Dengue Hemorrhagic Fever (DHF) is a potentially deadly complication that is characterized by high fever, the enlargement of the liver, and hemorrhaging.

Symptoms of Zika - fever, headache (behind the eyes), conjunctivitis, rash, vomiting, and muscle and joint pain - can appear two to seven days following contraction of the disease, although the virus is asymptomatic in approximately 80 percent of cases. Although the Zika virus is usually relatively benign, links between it and severe birth defects as well as the potentially fatal neurological disorder Guillain-Barre syndrome (GBS) have been established. Transmission of the virus is also possible via sexual intercourse.

Advice

Individuals present in Rio de Janeiro, and Brazil more generally, advised to take measures to protect themselves from mosquito bites (e.g. by wearing covering clothing, using insect repellent, and sleeping in screened-in or air-conditioned rooms).