Six suspected Zika cases await results

Two imported cases were confirmed earlier this week

Public Health Department officials said Wednesday they are awaiting test results on six suspected cases of the Zika virus.

On Tuesday, health officials announced two imported cases of Zika on island. The mosquito-borne virus was contracted overseas by two female residents. Health officials did not name the countries where the women had traveled.

To date, there are no confirmed cases of locally transmitted Zika virus.

“Preventing local transmission is our main focus,” said Acting Medical Officer of Health Samuel Williams-Rodriguez. “We will continue to work with the [Mosquito Research and Control Unit] and other relevant agencies and local healthcare providers in order to reduce local transmission to the minimum.”

He noted that large outbreaks of dengue and chikungunya have been prevented in Cayman.

“I am confident that we will have the same degree of success with Zika,” Dr. Williams-Rodriguez said.

He said that when people in the Cayman Islands exhibit Zika symptoms, which include fever, rash and/or conjunctivitis, they are advised to “take all the necessary measures to avoid being bitten by mosquitoes” but are not quarantined.

“The WHO [World Health Organization] and the PAHO [Pan American Health Organization] do not recommend quarantine for patients diagnosed or with symptoms suggestive of [the Zika virus],” Dr. Williams-Rodriguez said.

MRCU action

When a patient in the Cayman Islands is suspected of having contracted the virus, the Mosquito Research and Control Unit is notified and takes immediate action to control the Aedes aegypti species in the area where the person lives.

The Aedes aegypti mosquito, which can breed in very small amounts of water, is the only species of mosquito that carries Zika. It can be difficult to control by conventional means, and has also become resistant to many types of insecticides.

“Normally, we control that mosquito by targeting the immature species,” MRCU Assistant Director Alan Wheeler said.

Crews are sent out daily to put down larvicides to target the immature Aedes aegypti, he said. When someone begins exhibiting symptoms of the Zika virus, the MRCU targets the adult species of the mosquito by spraying chemicals in specific areas on the ground and from aircraft.

“We don’t want to be spraying a chemical randomly. We wait until we’ve got a suspected case and then we apply it,” Mr. Wheeler said. That process might change if the virus gains a foothold in Cayman, he said, adding that the MRCU is “well prepared to be dealing with this.”

GM mosquitoes

The MRCU and U.K.-based biotech firm Oxitec are preparing to release millions of genetically modified Aedes aegypti mosquitoes in West Bay to help fight the species. The release is scheduled to begin sometime this month.

The use of GM mosquitoes to fight the spread of Zika has been approved by the World Health Organization, which issued a statement in February encouraging “affected countries and their partners to boost the use of both old and new approaches to mosquito control as the most immediate line of defense.”