Zika virus in South America

The Pan American Health Organization reports continued transmission of Zika virus in South American countries. From 1 January 2025 to 22 March 2025, affected countries are:

Argentina: 497 cases

Bolivia: 31 cases

Brazil: 5 517 cases

Colombia: 3 cases

Costa Rica: 4 cases

El Salvador: 12 cases

Guatemala: 11 cases

Honduras: 2 cases

Mexico: 1 case

Peru: 1 case

Puerto Rico: 1 case

Zika virus disease is caused by the Zika virus (ZIKV). It is spread by mosquito bites which in pregnancy may result in congenital zika syndrome, with severe consequences for the baby.

Advice to travellers

Aedes mosquitoes, which transmit ZIKV, are particularly persistent and aggressive biters. They bite between dawn and dusk. All travellers to countries that have reported ZIKV infection must consider:

• strict mosquito bite avoidance measures, especially pregnant travellers and those planning pregnancy
• using condoms and contraception if sexually active, to avoid the sexual transmission of ZIKV and the risk of ZIKV in pregnancy, during travel and on return for 2 months (if female) or 3 months (if male)
• travel insurance: before booking their trip, pregnant women should check with their travel insurance company that both they and their unborn baby are covered under their policy if travelling to a country with a risk of ZIKV, and be aware that the risk of ZIKV in any country may change during the time between planning the trip and travelling
• if there are any additional travel recommendations for pregnant travellers, those planning pregnancy and for preventing onward sexual transmission: these will be listed under the 'Emerging Health Risks' tab of TRAVAX country pages

See the Zika Virus infection page for further information.