Prepared by Stanton E. Cope, Ph.D., Director, Entomology and Regulatory Services for Terminix and President, American Mosquito Control Association
Where did Zika virus come from?
ANSWER: The word ‘Zika’ means ‘overgrown’. The virus was first isolated in Uganda in 1947 from monkeys in the Zika Forest. The first isolation from humans was 1952 in Uganda and Tanzania.
How did Zika virus get here?
ANSWER: Zika virus moves around the world in infected travelers. Airline travel now allows a person to be anywhere in the world in 24 hours.
How is Zika virus transmitted?
ANSWER: Zika virus is transmitted primarily by the bite of an infected mosquito. Aedes aegypti, the Yellow Fever mosquito, is the primary mosquito. Aedes albopictus, the Asian tiger mosquito, is considered a secondary transmitter. To see maps of the potential distribution of these two species in the United States, go to http://www.cdc.gov/zika/vector/index.html. Both species breed in close association with humans in artificial containers such as tires, children’s toys, drainage dishes for plants, neglected fountains, etc. Basically, anything that will hold water. The mosquito life cycle can take as little as 5-7 days to complete. The virus can also be transmitted from a pregnant mother to her fetus during pregnancy or around the time of birth. Zika virus can also be transmitted sexually by a man to his sex partners.
Who gets sick and why?
ANSWER: After a person is bitten by an infected mosquito, Zika virus incubates in the blood for about 3-7 days. During this time, mosquitoes may acquire the virus by biting. Only about 20% of those infected actually will develop clinical illness.
Does Zika virus infect other animals?
ANSWER: Zika virus is only known to infect humans and higher primates (monkeys). Unlike West Nile virus, it does not infect birds. So, humans and primates are the only known reservoir for Zika virus.
What happens to a person who gets sick from Zika virus?
ANSWER: Zika is a mild, self-limiting disease with most patients recovering after about one week. The most common symptoms are fever, rash, joint pain, and conjunctivitis (pink eye). There is no vaccine and no specific medicines to treat Zika infection.
How many cases of Zika virus have occurred in the United States?
ANSWER: According to the Centers for Disease Control and Prevention, as of June 8, there have been 691 travel-associated cases reported in the United States. To date, there have been no locally-acquired cases from mosquito bites. Eleven cases have been sexually transmitted.
Will Zika virus establish in the United States such as West Nile virus has?
ANSWER: We do not think so. Unlike West Nile virus, which infects a wide range of birds, Zika does not infect other animals except primates so there will be no established animal reservoir. However, it is likely that Zika virus will continue to be introduced into the United States in infected travelers. This could result in domestic mosquitoes becoming infected, perhaps resulting in a few cases of local Zika virus transmission by mosquitoes in the United States.
What is different about the Zika mosquitoes and why are they so hard to control?
ANSWER: The mosquitoes that transmit the Zika virus are highly adapted to human environments, often being found within homes. They will breed in almost any type of container that will hold a small amount of water. Also, they tend to feed primarily during the daytime, when people are less likely to use repellents. Traditional mosquito control methods are mostly ineffective, as they are targeted toward mosquitoes, such as those that transmit West Nile virus, that bite in the evening and at night.
What can you do?
ANSWER: First and foremost, get rid of any standing water in your garden and yard. Look especially hard for small amounts of water that have accumulated. This should be done once a week. For gardeners, it is especially important to regularly empty the drip saucers under plants. If mosquitoes are present, wear long-sleeved shirts and long pants, and use an EPA-registered insect repellent. Finally, ensure that the door and window screens on your home are in good repair.
For more information on Zika virus, contact your state health department or visit http://www.cdc.gov.
For information on pest control, visit Terminix.com.
All articles are copyrighted and remain the property of the author.