John Elflein
Research expert covering health and health care
Zika virus - Statistics & Facts
The Zika virus is spread mostly by bites from infected Aedes aegypti or Aedes albopictus mosquitoes, but mother-to-child and sexual transmissions are also possible. Infected persons often have symptoms such as a low-grade fever, red eyes, joint pain, rash, and sometimes muscle pain and headache. As there are many other diseases with similar symptoms, there was no special attention paid to Zika until more recently. This rapidly changed after the latest outbreak in Brazil which began in early 2015 and ended in November of 2016 with an offical declaration from the World Health Organization. In 2015, increased evidence pointed to infections with this virus which could cause serious birth defects and neurological problems, the most well-known of which was microcephaly.
Brazil was by far the country most affected by this epidemic, reporting the most cases of people infected with the Zika virus worldwide. In 2016, Brazil reported almost 274 thousand Zika virus infections. However, by 2017, this number had already dropped significantly, with only 31,750 cases reported. In the year 2023, there were around 35 thousand cases of Zika virus in Brazil. In 2022, the northeastern state of Rio Grande do Norte was by far the Brazilian state most impacted by the Zika virus.
The 2015-2016 Zika virus epidemic
The latest outbreak began in early 2015 in Brazil, although the first cases seemed to have already appeared in 2014. One theory is that the virus arrived during the 2014 Football World Cup. Zika virus infections were reported on all continents, however, the Americas were the most at-risk-part of the world. In 2017, it was estimated that over 120 million people in Brazil were at risk of Zika virus infections, compared to 32 million people in Mexico and 29.5 million in Columbia. At the height of the epidemic in 2016, there were over 522 thousand cases of Zika virus in Latin America and the Caribbean. However, in the year 2023 there were only around 36.7 thousand cases in this region.Brazil was by far the country most affected by this epidemic, reporting the most cases of people infected with the Zika virus worldwide. In 2016, Brazil reported almost 274 thousand Zika virus infections. However, by 2017, this number had already dropped significantly, with only 31,750 cases reported. In the year 2023, there were around 35 thousand cases of Zika virus in Brazil. In 2022, the northeastern state of Rio Grande do Norte was by far the Brazilian state most impacted by the Zika virus.
The Zika virus in the United States
In the United States, there were 62 Zika virus infections reported in 2015, then over 5,000 reported in 2016, and only five in 2022. Florida was the state with the highest number of reported Zika virus cases in 2016, with 1,115. However, provisional data shows that there were no Zika cases in Florida in 2019 or 2020. As of 2022, only around 22 percent of U.S. adults stated they were "very concerned" or "somewhat concerned" about the Zika virus in the United States.
