At the Humacao cemetery on Puerto Rico's east coast, an elderly woman arranges artificial flowers at a gravestone, talking to herself or perhaps to a departed loved one. Though colorful, the plastic flowers are a pale imitation of the real thing. Yet they're the only flowers authorities allow in the island's cemeteries, as part of efforts to clean up breeding sites for Aedes aegypti, the mosquito that transmits Zika, dengue and chikungunya.
On Feb. 5, 2016, Puerto Rico declared the spread of Zika to be a public health emergency and began stepping up action to eliminate potential mosquito breeding sites, which include the vases and flower pots that adorn headstones in Puerto Rico's 78 municipal and 32 private cemeteries.
Requiring that all flowers be artificial, however, is only a partial solution. Unlike real flowers, artificial flowers do not need watering. But the vases and flowerpots they come in must be filled with dirt or rocks to prevent them from collecting water.
"We are placing priority on cemeteries because people put artificial flowers in pots without dirt or rocks, and those can collect rain water and become prime breeding spots for mosquitoes," says José Luis Dalmau, president of the Health Commission of the Puerto Rican Senate.
Across Puerto Rico, cemeteries lie within communities' perimeters, and mosquitoes born in those cemeteries can fly just a few meters to reach human housing.
"Most of the people buried here have been here more than 100 years, and many no longer have any family left. So we have to take care of any containers and also maintain and protect any broken gravestones from collecting rainwater," says José Baéz, director of the Office of Emergency Management in Humacao.
Authorities are also fumigating cemeteries and treating water receptacles with larvacide to kill larvae before mosquitoes can be born.
These anti-Zika actions are being implemented by the Government of Puerto Rico, the Department of Health, mayors, communities and the private sector, which together have formed a national alliance to fight the mosquito vector.
"We have to be sure we are eliminating mosquito breeding sites in a systematic way," says Johnny Rullán, an epidemiologist and former secretary of health of Puerto Rico. He said the goal is to ensure that, by April 1, breeding sites in every community are under control, to protect pregnant women from a virus that is suspected of causing microcephaly and other birth defects in newborns.
"We have 100 newly pregnant women every day in Puerto Rico," adds Rullán, adding that it's essential to eliminate Aedes breeding sites in homes, workplaces and schools, and to ensure that people use repellent and mosquito netting so that by October 2016, the island "can declare that no pregnant woman has transmitted Zika to her baby."
Aedes mosquitoes breed primarily in and around people's homes. Eliminating, covering, treating or inverting containers or other items that can collect water is key to controlling the mosquito and reducing the risk of infection with Zika, dengue and chikungunya. As of Feb. 18, 2016, Puerto Rico had reported 63 confirmed cases of Zika, three of them pregnant women and one diagnosed with Guillain-Barré syndrome, according to official data.
Discarded tires, which also collect water, are another main breeding site for mosquitoes. Josué Figueroa, who manages an auto shop in Humacao, says his staff changes some 800 tires every month. A few weeks ago, he says, municipal authorities hauled away around a thousand discarded tires from the premises. "Getting rid of them is good for all or us," Figueroa says.
"We are doing our part in the cemeteries, with tires, and in vacant lots, but we also need members of the community to do their part in their homes and patios," says Dalmau. "Fighting Zika is everyone's responsibility."
The Pan American Health Organization (PAHO), regional office for the Americas of the World Health Organization (WHO), is providing technical cooperation on vector control to health authorities in Puerto Rico. Since before WHO's declaration of an international health emergency due to suspected links between Zika and microcephaly in newborns, PAHO has been providing assistance to countries throughout the Americas to fight Zika as well as dengue and chikungunya.