Puerto Rico reported its first case of a mosquito-borne disease that was recently introduced to the Americas and is possibly linked to a birth defect that causes newborns to have abnormally small heads.
Known as the Zika virus disease, its most common symptoms are fever, rash, joint pain and red eyes, but can also include muscle pain, headache, pain behind the eyes and vomiting.
Zika’s symptoms are generally milder than dengue fever’s and hospitalization is uncommon. To date, the Zika virus has not caused any deaths.
The newly confirmed case prompted the CDC to issue a travel notice advising people traveling to the Virgin Islands and Puerto Rico to take precautions to protect themselves from mosquito bites. (See link to Travel Notice in Related Links below)
“No cases have been diagnosed in the territory as of yet; however, we are taking every precaution to prevent an outbreak here in the territory,” acting Commissioner Juan Figueroa-Serville of The Virgin Islands Department of Health stated.
The spread of the disease has caused recent alarm in Brazil, due to the possible link between infected pregnant women and microcephaly, a birth defect that causes children to be born with smaller than average heads and brains, usually resulting in an intellectual disability.
“Since there are many causes of microcephaly in babies, it will take some time to determine the cause of these cases. The investigation looking into the correlation is ongoing,” said Dr. Esther Ellis, the territorial epidemiologist for the DOH.
The Puerto Rican case was locally transmitted, meaning the infected person had not recently traveled, so the disease is present in mosquitoes on the island. Because of Puerto Rico’s proximity to the V.I., the virus could easily be spread to the territory just like chikungunya did less than two years ago.
“The threats are similar to what we experienced with past dengue and chikungunya outbreaks. Microbes know no boundaries, and neither do mosquitoes,” Ellis said.
Ellis added that the Zika virus is spread by the same type of mosquitoes as dengue and chikungunya, but that it stays present in the blood for a shorter time that the other two. That means there’s less time for the mosquito to bite an infected person and spread the Zika virus to others.
“There’s no way to predict when or if it will appear in the V.I.; however, we are preparing now through education of providers and the public, as well as submitting any suspected cases to the CDC for laboratory testing,” Ellis said.
In order for the Zika virus to cause an outbreak in the V.I., first a person with the virus would need to enter the territory. Then the type of mosquito that carries the virus would need to bite the infected person during the short window that the virus is circulated in the blood. If the mosquito lives long enough, it can bite another person and infect them.
Puerto Rico is the first Caribbean island to report a case of Zika virus, while in 2014 Easter Island became the first place in the Americas to report a locally-contracted case of Zika, which was related to other outbreaks in the Pacific Islands.
Ellis said the Zika virus could potentially be present on other Caribbean islands, but there haven’t been any suspected cases yet outside of Puerto Rico.
Brazil reported its first local case of Zika virus disease in May. Since then 12 other countries and territories, mostly in Central America and along South America’s Caribbean coast, have reported cases. There is no vaccine for the Zika virus or medicine to treat it, as is the case for dengue and chikungunya.
First identified in Uganda’s Zika Forest in 1947, outbreaks have been reported in tropical Africa, Southeast Asia and the Pacific Islands, and experts expected that it is likely to spread to other areas.
Ellis noted that climate change plays a role in the geographic spread of some vector-borne diseases. For example, changes in rainfall patterns and temperature ranges can affect the reproductive cycles of vectors such as mosquitoes.
The CDC is testing all recent samples for Zika that were previously confirmed negative for dengue and chikungunya.
To help prevent the spread of mosquito-borne viruses, the CDC recommended that people wear insect repellent, use screens to keep mosquitoes outside, wear long pants and long-sleeved shirts when possible and empty standing water near the home.
The V.I. DOH recommended that anyone experiencing the symptoms of Zika seek care from a medical provider. If the provider suspects the patient has Zika, he or she can call Ellis in order to submit a specimen for laboratory testing at 340-718-1311 ext. 3241.