Puerto Rico Looks East for Help With Zika Mosquito
March 17, 2016 -- San Juan, P.R. -- In Puerto Rico, they’re trying to figure out once again how to kill the mosquitoes.
The island U.S. territory has been fighting Aedes aegypti mosquitoes and the diseases they spread -- including dengue fever, chikungunya, yellow fever, and now Zika -- for over a century. But Aedes are hardy and adaptable. They’ve thrown public health experts some curveballs that are forcing them to rewrite the mosquito-fighting playbook here.
And they’re looking halfway around the world for help.
“Nobody, except for Singapore, has been able to give Aedes aegypti the good fight,” says Brenda Rivera Garcia, DVM, state epidemiologist for the Puerto Rico Department of Health.
Singapore's natural features and population are a lot like Puerto Rico's. Both islands have tropical climates, which means mosquitoes are a year-round problem. Both have higher-than-average numbers of people per square mile. Both have been battling epidemics of dengue fever for decades.
In the 1960s, Singapore carried out an extensive public health campaign using an army of inspectors, who scoured homes and residential areas for potential breeding sites, Rivera says.
The campaign was effective. By the early 1970s, the country had tamped down dengue so well that experts think most people in Singapore lost their immunity to the virus. That has allowed dengue to return there full force in recent years.
Puerto Rico doesn’t have the money to roll out a full Singapore-style campaign, but health department officials are hoping to borrow some of the main strategies used there to head off Zika.
The first step in fighting Aedes mosquitoes is always getting rid of even tiny amounts of water that may collect in and around a house.
In Singapore, an ad campaign prompts residents to “Do the 5-step Mozzie Wipeout.” The five steps target the most common mosquito breeding sites around homes -- urging people to empty vases and flower pot plates every other day, cover bamboo pole holders, turn over water-holding containers like buckets, and regularly treat roof gutters with insecticides.
Puerto Rico is working on a similar public awareness campaign. They don’t exactly know how it will look yet, but Rivera says they’re honing in on the idea of “herd immunity” to protect the most vulnerable residents on the island: pregnant women. Zika virus has been strongly linked to serious birth defects of the brain and nervous system in babies of infected women.