As the threat of infected mosquitoes reaching the U.S. climbs, the Air Force continues to closely monitor the emergence of Zika virus infections to help inform and protect Airmen and their families. 

The World Health Organization declared Feb. 1 that the Zika virus is a public health emergency of international concern. According to the Centers for Disease Control and Prevention, all at-risk communities should prepare for possible Zika activity. 

Col. (Dr.) John Oh, the Air Force Medical Support Agency’s chief of preventative medicine, explains that Zika is primarily transmitted by Aedes mosquitoes. Unlike other mosquitoes, Aedes mosquitoes are aggressive day biters but can also bite at night. 

Almost all cases of Zika virus infection within the U.S. have come as a result of a mosquito vector obtained through living and traveling in Zika-infected areas, the colonel said. 

“The number of countries and territories with Zika transmitted locally is growing. There are over 45 now, including countries in Central America, South America, the Caribbean, Asia and Africa,” he said. 

It is also possible for the Zika virus to be sexually transmitted from males to females. Thus far, there have been no reported sexual transmissions from female to male. 

“The symptoms of Zika virus infection are similar to dengue, another mosquito born infection, and include fever, skin rashes, headaches and joint pain,” Oh said. “However, unlike dengue, Zika symptoms are usually mild, and many infected people don’t have any symptoms.

“Evidence now supports that there is a risk of birth defects from Zika virus,” he continued. “There is enough evidence that it is causal; however, there is still a lot we don’t know about birth defects and Zika. Eighty percent of cases are asymptomatic.” 

The colonel advises pregnant women to take every precaution to prevent mosquito bites, especially in the first trimester. 

In response, the Air Force has developed policy guidance for relocation of pregnant Air Force members and dependents from outside the continental U.S., in areas where there is active transmission of the virus. 

“When considering this policy, we really encourage pregnant women to consult with their health-care providers,” Oh said. “Health-care providers can help to assess individual risk of Zika infection, factoring in the home environment, for a shared decision between patients and their providers.” 

He also encourages pregnant women diagnosed with Zika to enroll in the U.S. Zika Pregnancy Registry. The registry follows those enrolled and data collected helps improve prevention of Zika virus infection during pregnancy and updates clinical care recommendations. 

“Everyone can help prevent Zika by getting rid of standing water where the mosquito vector can breed. We all need to pay careful attention to our surroundings,” Oh said. 

According to the Air Force Integrated Mosquito Management publication, any container that holds water for five to seven days can breed mosquitoes.

Breeding areas include:

• Discarded cans and plastic containers

• Glass bottles or any broken bottles

• Tires and tarps

• Obstructed roof gutters

• Plant pot saucers

• Holes in unused construction blocks or bricks

• Pipes

• Barrels (Rain barrels or other storm-water collection containers should be treated with mosquito larvicides or mosquito fish to prevent mosquito development)

Outdoor equipment tips:

• Bird baths should be drained and refilled at least weekly

• Pet food and water bowls should be emptied and filled daily

• Flower pots with bases that hold water should have excess water drained if left outdoors

• Yard equipment should be stored so as not to collect water 

Features of Aedes mosquitoes:

• Lives outdoors, but comes indoors

• Egg to larva to adult in one week or less

• May lay eggs indoors

• Rests in low, shaded areas such as under tables and chairs

• Silent flier, with no buzzing

Protection:

• Use Environmental Protection Agency-registered insect repellant, according to product label

• Treat clothing with permethrin insecticide

• Stay inside air-conditioned or screened buildings

• Wear long-sleeved shirts and long pants

• Empty containers of water weekly

Any beneficiary who has a question about travel health or Zika is encouraged to visit public health, even before a planned trip.