Zika virus is carried by mosquitoes, and the symptoms of Zika infection are usually mild in adults. A single mutation could make Zika virus a lot more dangerous. However, the virus can infect a developing fetus, resulting in birth defects such as microcephaly.
Zika virus and dengue virus overlap in many countries worldwide. Like Zika, dengue virus is a mosquito-borne flavivirus, and thus shares many biological properties. In fact, the viruses are similar enough that the immune response sparked by prior dengue exposure can offer protection against Zika.
“In areas where Zika is prevalent, a vast majority of people have already been exposed to dengue virus and have both T cells and antibodies that cross-react,” says Shresta.
Unfortunately, both viruses are also quick to mutate. “Dengue and Zika are RNA viruses, which means they can change their genome,” explains Shresta. “When there are so many mosquitoes and so many human hosts, these viruses are constantly moving back and forth and evolving.”
Zika virus risk for a country list 2022
To determine the Zika risk for a country or area of travel, use the A to Z and follow the links to country specific travel advice from NaTHNaC.
Read also: The Omicron offshoot BA.2 is now the dominant variant
Note: This list will be subject to change as the Zika virus outbreak situation in each area continues to evolve. It is strongly advised to continuously refer back to this list (which will be kept updated) and not rely on printed copies.