Zika Is the Next Front in the Mosquito Wars

 Based on damage from malaria and dengue, the spread of Zika will prove costly.

The Aedes aegypti mosquito weighs less than a grain of rice, lives only a few weeks, and doesn’t stray more than 100 yards from where it hatches. For a creature of such limited scope, it has an outsize influence on human health and global commerce. In 1793 a mosquito-carried epidemic of yellow fever in Philadelphia shut down trade and killed a 10th of the city’s residents. A century later, the same disease foiled France’s effort to build a canal across Panama.

Aedes aegypti is now spreading the Zika virus through Latin America. The virus, detected in Brazil for the first time last May, is suspected of causing an increase in babies born with abnormally small heads, a serious birth defect known as microcephaly. With no vaccine or cure for Zika, “the most effective protective measures are the control of mosquito populations and the prevention of mosquito bites,” Margaret Chan, director-general of the World Health Organization, told reporters on Feb. 1. Officials in Texas on Feb. 2 identified a case of sexual transmission of the disease.

“Mosquito-borne diseases are among the most preventable and yet the most expensive,” says Lawrence Gostin, a professor of global health law at Georgetown Law. He estimates that the costs of responding to the Zika epidemic will reach “well into the billions,” counting money spent on a vaccine. The pattern of other mosquito- borne illnesses suggests Zika will be costly in a variety of ways. The number of years lost due to ill health, disability, or early death, “not to mention the huge cost to health-care systems, is very substantial,” says Stephen Higgs, president of the American Society of Tropical Medicine & Hygiene and the director of the Biosecurity Research Institute at Kansas State University.

The WHO estimates there could be 3 million to 4 million cases of Zika in the Americas this year. In Brazil, President Dilma Rousseff’s administration has warned pregnant foreigners against traveling to Rio for the Olympics in August. Pregnant women across Brazil are scouring pharmacies for bug repellent. Many are canceling trips to northeast Brazil, the outbreak’s epicenter.