The Aedes aegypti mosquito is one of two types that can carry the zika virus.

The Aedes aegypti mosquito is one of two types of mosquito that could spread the Zika virus in the United States.

by James Hubbard, MD, MPH

Zika virus is in the news. It’s an infection you get from certain types of mosquitoes, and it’s linked to a sometimes devastating birth defect called microcephaly. More on that later. Here are the latest facts on the disease and why you should care.

Why Is Zika in the News Now?

The World Health Organization believes Zika has been prevalent in parts of Africa for a long time. It’s thought that once you get the virus, you’re immune.

Lately, Zika has been found in South America, Puerto Rico and Mexico. Since it’s a relatively new virus for people in these areas, they’re not immune, and more pregnant women are getting the disease.

Some people from the United States who have traveled to these areas have developed the virus. As of this writing, however, there have been no cases of mosquito-to-human Zika transfer in the U.S.

Other Than for Humanitarian Reasons, Why Should Preppers, Campers, and Hikers Care, in Particular?

Mosquitoes lay their eggs in even the smallest pools of water. With the usual debris after disasters, there are many more pools than normal in which they can do just that. More mosquitoes, more chance of disease.

And with stress, fatigue, and the possible scarcity of water and food, your immune symptom may become weak, making it harder to fight off the infection and, theoretically, more likely that a severe infection may occur.

How Is the Zika Virus Spread?

Once a human is infected, Zika stays in the blood for about a week. Mosquitoes can pick up the virus at any time during this week and then pass it on to more humans. Zika is also spread by sexual contact. Although it stays in the blood a relatively short time, it may remain in semen for months.

What Are the Symptoms of the Zika Virus?

Most people with Zika never have symptoms and don’t even know they’re infected. If symptoms occur, they start a few days after exposure and last about a week. Common symptoms include generalized muscle aches, fever, joint pain, and a rash. The rash is bumpy and red, and it lasts about three days. It starts on the face (the eyes get red and irritated also) and then spreads to the rest of the body.

Some Zika infections cause meningitis or, rarely, death. There is a test that can be done to see if you’re infected, but blood has to be sent to the Centers for Disease Control and Prevention.

What Are the Complications of Zika?

If a pregnant woman is infected, the virus can cause microcephaly—i.e., small head—during fetal development. Some cases are not severe, but in many others the microcephaly inhibits brain development and can cause other brain damage.

Not all microcephaly is due to Zika. In the U.S., it occurs in about 10 in 10,000, or 0.1 percent, of births, many times for unknown reasons. Zika can also cause miscarriages and eye problems.

Zika is just now getting serious study, so more complications may be found.

The Aedes albopictus is one of two mosquitoes that can carry the zika virus.

The Aedes albopictus, which lives in parts of the United States, can spread the Zika virus but is less likely to than the A. aegypti (which is shown in the first photograph).

Why Don’t U.S. Mosquitoes Spread It Right Now?

There are around 175 species of mosquitoes in the United States. Zika is one of several infections that can be spread by two of these species, A. aegypti and A. albopictus.

Both species are found in certain areas of the United States, and their range is slowly spreading. These mosquitoes are known to bite in the middle of day as much as or more than at night.

However, the mosquito must:

  1. Bite someone who has the virus in their bloodstream.
  2. Get the virus (not always the case).
  3. Bite another person, injecting the virus into them (not always the case).

In the United States, only a few people who have traveled to countries where the disease is prevalent have come down with the infection. So the odds are small, but possible, a mosquito will bite that person during an active infection and that mosquito spread it to another person.

In order for a widespread outbreak to happen, statistics tell us, a lot of people must already be infected.

What Are Some Zika Prevention Tips?

If you’re a woman, unless you have to, don’t go to countries where the virus is spreading if you could be pregnant or could become pregnant soon afterwards.

Men who travel there should not have sex without a condom with a pregnant woman or anyone who might become pregnant. So far, the Zika virus has been found in semen of men who have had a symptomatic infection for as long as three months. We’re not yet sure how long it can actually stick around. Current CDC recommendation is no sex without a condom for at least six months.

Right now it’s not known if the virus also stays around in men who are infected but never have symptoms. The current recommendation for them is condoms for eight weeks at least.

For further information, click here to read the CDC’s guidelines as of March 25, 2016.

When you’re in one of the affected countries, use mosquito nets if available, don’t open windows without adequate screening, and use mosquito repellants.

What’s the Treatment for the Zika Virus?

As with the vast majority of viruses, there is no cure for Zika other than to wait for the body’s immune system to fight the virus off. To help your body, drink plenty of fluids, rest, and eat healthy.

Remember, Zika virus is only one of many infections spread by mosquitoes. There’s also dengue fever, chikungunya, West Nile, and malaria, to name a few. Taking precautions to prevent bites is always a good idea.

What precautions have been effective for you, or do you just not worry about bites at all?

Next post—best mosquito repellents and how to use them.


Photo of A. aegypti courtesy CDC/ Prof. Frank Hadley Collins, Dir., Center for Global Health and Infectious Diseases, University of Notre Dame. Photo of A. albopictus courtesy CDC/James Gathany.