By Robert J. Novak and Paul Driesssen
The Zika virus is raising alarms. It can cause serious neurological complications for women and babies, and microcephaly in newborns: smaller than normal heads and brains, and severe debilities requiring expensive care throughout a person’s life.
Although Zika can be transmitted via sexual contact, its primary carrier is Aedes aegypti. Known as the Yellow Fever mosquito, this flying killer has rebounded from near eradication in the 1960s to being a dangerous scourge in Brazil, other South and Central American countries, Puerto Rico, Caribbean islands, Africa, and Asia.
Found in Hawaii and some southern U.S. states and European nations, as well, they also carry other dangerous diseases. Yellow fever causes fevers, chills, nausea, muscle pains, and liver and kidney damage when these symptoms recur. A vaccine exists, but it still kills up to 30,000 people annually.
Equally painful and debilitating, dengue fever can recur for years; there is no vaccine, and it sickens nearly 100 million people a year, killing some 25,000. Chikungunya causes often severe fever, headaches, muscle and joint pain, rashes, and other non-lethal problems.
All these diseases also infect blood supplies, making transfusions risky and requiring blood from safe locales that often lack sufficient supplies themselves.
The prospect that Summer Olympics fans and athletes could get infected and carry these diseases from Brazil back to their home countries has health officials worried. So does the likelihood that thousands of other travelers will also spread these diseases.
Rarely flying farther than 80 feet from where they hatch, Ae. aegypti love people and houses, bite during the day, and hatch from eggs laid in tires, cans, jars, flower pots, vases, bromeliads, holes in trees, and almost any other container holding water around homes, indoors and outdoors, in backyards and junkyards.
A promising high-tech solution involves releasing male mosquitoes that have been sterilized by radiation, so they cannot mate successfully — or genetically modified so their progeny die before reaching maturity. Since male mosquitoes don’t bite, releasing them into urban areas poses few health risks.
At least one experimental GMO effort has been field-tested, somewhat successfully, with gradual but noticeable reductions in mosquito populations in test areas. Some politicians, disease control experts and researchers would like the program’s funding expanded.
However, field tests are just that: tests. The experimental programs must still survive long U.S. Food and Drug Administration and Agriculture Department approval processes, budgetary constraints, anti-biotechnology and anti-radiation activism, and international concerns.
It is thus highly unlikely that either program can be ramped up sufficiently to help in the near-term across the sprawling Rio de Janeiro Olympics venues, urban areas and shantytowns — much less across millions of square miles in Latin America, Africa, Asia, and beyond.
Until the sterilized or GMO methods can be approved and implemented on a large scale at reduced costs, other strategies must be employed to eliminate the mosquitoes and the diseases they spread.
Fortunately, the World Health Organization, national health ministries, neighborhoods, and individual families can undertake simple, low-cost actions that will bring rapid, significant returns with the limited time, money and resources available — by eliminating mosquitoes and keeping them away from people. They need to do so, now.
1) Destroy mosquito-producing sites. Empty containers every week; punch holes in cans and tires, so they cannot collect water; fill in other standing water areas with dirt. Where this is not possible, use chemicals.
2) Used properly, today’s larvicides and insecticides are safe — especially compared to the misery and devastation spread by mosquitoes. Centers for Disease Control, National Institutes of Health, and other studies have concluded that the most commonly used larvicides (BTI and Temephos, aka Abate) are safe for humans and mammals, even in drinking water.
3) Use personal insect repellants, preferably those containing DEET, even while indoors, and keep skin covered with clothing. To keep mosquitoes out of homes, screens, spatial repellents like DDT can be sprayed on walls and doorways.
4) Educate politicians, local leaders, teachers, neighborhood organizations and citizens about the dangers posed by mosquitoes and the diseases they carry — and what they can do to help. Launch and coordinate home and neighborhood programs, and emphasize why they must continue well into the future.
5) Employ cellphone GPS systems to locate and monitor mosquito populations, biting incidences, and disease outbreaks. Tie these efforts into local or national databases and monitoring and surveillance programs that can dispatch response teams.
Preventing mosquito bites breaks the disease transmission cycle and is especially important for people attending the Olympics or vacationing where problems exist, so they don’t take diseases home.
6) Test people for antibodies, especially pregnant women, to determine whether they have Zika or other mosquito-transmitted diseases. The RT-PCR test can find Zika proteins and genetic material in people and in the brains and placentas of infants and miscarried fetuses, and can rule out Dengue, Yellow, and Chikungunya fever viruses.
This arsenal of potential weapons represents truly integrated vector and disease control.
It’s not as sexy as irradiated or GMO bugs. But, history shows it will save lives now — in time for the Olympics, and before these awful, preventable diseases claim more victims.
• Robert J. Novak is professor of medicine and infectious diseases at the University of South Florida in Tampa and a member of CFACT’s Board of Advisors. Paul Driessen is senior policy analyst for the Committee For A Constructive Tomorrow and a veteran of anti-malaria campaigns.