The Hawaii Department of Health (DOH) has confirmed a travel-related case of Zika virus on Oahu, the state’s first in 2024.
A similar case was reported in May 2023, also on Oahu. According to DOH, travel-associated Zika cases were more common from 2015 to 2019, peaking at 25 in 2017, when the virus circulated globally. No locally acquired Zika cases have been reported in Hawaii to date.
Zika, like dengue, is primarily transmitted through the bite of an infected mosquito. While mosquito species capable of spreading Zika exist in Hawaii, the virus is not established in the state. Zika can also be transmitted sexually and from a pregnant person to a fetus, according to the Centers for Disease Control and Prevention (CDC). Infection during pregnancy can lead to serious birth defects and complications, including miscarriage, stillbirth, and preterm birth.
Common symptoms of Zika include fever, rash, headache, red eyes, and muscle or joint pain, though many people experience mild symptoms or none at all, the CDC said.
Separately, DOH confirmed another travel-related case of dengue on Oahu. That case will be counted among Hawaii’s 2025 dengue cases based on the onset of symptoms and marks the 15th such case for that year.
Symptoms of dengue include fever, rash, nausea, vomiting, and body aches, including pain behind the eyes.
The cases are unrelated, and the individuals were exposed while traveling in areas where the viruses circulate, DOH said.
“DOH teams have been deployed to conduct outreach, inspections and implement mosquito control measures in the affected areas,” the department said. “Because both Zika and dengue are transmitted by mosquitoes that exist locally, controlling mosquito populations in the affected areas is critical to preventing spread.”
DOH said it would continue monitoring mosquito levels but did not specify which areas of Oahu were affected.
The CDC recommends travelers review Zika and dengue risk information before departure. People who develop symptoms within two weeks of visiting affected areas should consult a doctor and report possible exposure. Health care providers and individuals who suspect infection are asked to call the Disease Reporting Line at 808-586-4586.
