Zika
What mosquitoes can carry and transmit Zika virus?
The mosquito primarily responsible for Zika virus transmission in the Americas is Aedes aegypti, the yellow fever mosquito. Aedes albopictus, the Asian tiger mosquito, has also been shown to transmit Zika virus in Africa and in laboratory studies.
Where do they live?
Both the yellow fever mosquito and the Asian tiger mosquito are found throughout much of the United States. They are also globally distributed in tropical and subtropical areas. The mosquito life cycle is defined by four major life stages: 1) egg, 2) larva, 3) pupa, and 4) adult.
The adult is the life stage people are likely the most familiar with. In the adult stage, mosquitoes fly around, and the females try to feed on our blood.
However, people may be less familiar with larvae and pupae, or the immature stages of mosquitoes that live in the water. More specifically, the yellow fever mosquito and the Asian tiger mosquito live in artificial and natural containers around human dwellings. These containers can potentially be anything that holds water including a tree hole, bird bath, clogged rain gutter, children’s toys, garbage, tires, and a range of other items.
Unlike many other nuisance mosquito species, as adults, both the yellow fever mosquito and the Asian tiger mosquito are primarily looking to feed on human blood during the day, when people are the most active. It is important to note that only the female mosquito feeds on blood.
What can I do to prevent infection?
KEEP EMPTY
Eliminating Immature Mosquito Habitats
The immature stages of these two species inhabit containers that are found around our homes. Eliminating immature mosquito habitats is an excellent way to prevent mosquitoes from completing their life cycle. This practice is known as source reduction.
To do this, simply go around your home and identify any containers that are holding water. Trash items can be discarded. For containers that will regularly refill with water, dumping out the water every five days will prevent immature mosquitoes from being able to reach adulthood. As an extra step, scrub the interior surfaces of the container with a sponge to dislodge any remaining mosquito eggs and rinse them off. If you have tires on your property, check with your local mosquito control or waste management company to find out if there are any programs in place to help you dispose of the tires on your property. For decorative ponds that cannot be emptied out regularly, consider stocking it with mosquito fish (ex: Gambusia affinis, Gambusia holbrooki) or utilizing a biological control agent, such as products with the active ingredient Bti (Bacillus thuringiensis subspecies israelensis).
Using Repellents
In addition to regularly practicing source reduction, using repellants when outdoors and wearing long sleeves and pants can prevent mosquitoes from feeding on you. When using repellents, make sure to choose from the list of CDC-recommended repellents.
Protecting Your Home
Preventing mosquitoes from entering the home is also important in preventing mosquito bites. This includes ensuring that all windows are covered with screens and that the doors to the home remain closed. Essentially, all entry points to the home should be sealed or covered by a screen. These screens should be checked regularly to ensure that there are no holes that would allow a mosquito to slip through. Damaged screens can be repaired or replaced to prevent mosquitoes from entering the home.
What are the symptoms of Zika virus infection?
The most common symptoms of an illness due to Zika virus are fever, rash, headache, joint pain, red eyes, and muscle pain. These symptoms are often mild and may last several days to a week. Of the individuals infected with Zika virus, only 20% exhibit symptoms. Symptoms will usually begin two to seven days after being bitten by an infected mosquito.
What does the Zika virus transmission cycle look like?
In urban settings, Zika is transmitted primarily by mosquito bite, although it can also be transmitted through sexual intercourse, blood transfusion, and from a mother to her fetus.
A female mosquito can become infected with Zika virus after feeding on an infected person. Once she finishes taking the bloodmeal, she cannot immediately transmit the virus to another person. The virus incubates and multiplies within the mosquito. During this time, she will lay her eggs and eventually look for another bloodmeal. It is during these future bloodmeals that she may be capable of transmitting Zika virus to a new person. That person then becomes infected, which creates a cycle of virus transmission between humans and mosquitoes.
