An Aedes aegypti mosquito is photographed through a microscope in Recife, Brazil, on Jan. 27. (Felipe Dana/Associated Press)

EVIDENCE IS mounting that the mosquito-borne Zika virus is a potentially serious health threat. While symptoms are typically mild, the consequences can be severe, such as microcephaly in infants born to women with the virus. The condition is characterized by a small head and damaged brain. According to Francis Collins, director of the National Institutes of Health, an NIH-funded study showed that the virus can infect and kill human neural progenitor cells that give rise to the cerebral cortex, a crucial portion of the brain. Another study, involving women diagnosed with Zika during their pregnancies in Rio de Janeiro, suggests the attack rate is “disturbingly high,” and microcephaly is just one of many risks. So far, Central and South America have been hardest hit, but the United States’ Gulf Coast is vulnerable, too.

There is no quick fix. The virus is primarily transmitted by the bite of an infected Aedes aegypti mosquito, the species that also spreads the dengue and chikungunya viruses.

The most direct response is vector control, or fighting the disease-carrying mosquito population. But spraying pesticide can be labor-intensive and difficult. As Post reporters Nick Miroff and Brady Dennis pointed out, a much-heralded international effort in the 1940s and 1950s eliminated Aedes aegypti from 18 countries in Central and South America, but that success was reversed by years of fading political will and rapid urbanization. The crowded, poverty-stricken sections of cities in Latin America are a perfect setting for Zika’s spread. The mosquitoes breed in small amounts of water and hide in the shadows of homes. Many of the most vulnerable people to Zika infections are the poor, who have less protection in screens or air conditioning. In the United States, mosquito control is the responsibility of a crazy-quilt of local districts, which may not be up to the task of battling a major outbreak.

Aside from spraying, there are other approaches, such as irradiating male mosquitoes to sterilize them, leading a population of insects eventually to die off. And the age of genetic engineering has brought new possibilities: The tiny building blocks of life can be manipulated to impede the disease. So far, laboratory trials have shown that genetic material can be altered to suppress mosquito populations or make them less likely to ferry disease. More recent science has suggested that a mosquito gene “drive” could be created that would pass down to generations of mosquitoes the characteristic of resisting a disease such as malaria. This technique has enormous implications for entire ecosystems, and research ought to be carried out with the utmost care. It may not be the answer to this epidemic, but it is important to explore. Would the world be worse off if Aedes aegypti were genetically altered, now and forever? A lot of human babies might have a better chance to be born healthy.