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Zika Virus Poses Risk for Pregnant Women

Most People Infected Have No Symptoms

The mosquito-borne Zika virus has become a concern in the United States, particularly for pregnant women whose infants can suffer serious Zika-related birth defects. The Zika virus is mainly transmitted to people by Aedes mosquitoes, which are not native to California; however since 2011 they have been detected in several counties including Alameda, according to the California Department of Public Health (CDPH).

The vast majority of Zika cases in the U.S. have been travel-associated, meaning those infected contracted the virus in another country where the Aedes mosquitoes are more prevalent, according to the U.S. Centers for Disease Control and Prevention (CDC). The virus can also be sexually transmitted, but that accounts for a small number of cases as well.

Since January 2015, there have been 2,722 cases of Zika in the U.S, the CDC reported on August 31. Of those, 2,686 were travel-related and 23 were sexually transmitted. According to the CDPH, there were 241 cases in California as of September 2, all travel-related except one, which was sexually transmitted. Sixteen of those cases were in Alameda County.

“About 80 percent of people who are infected with the Zika virus don’t have any symptoms,” said Dr. Dianne Martin, a Washington Township Medical Foundation physician and member of the Washington Hospital medical staff who specializes in internal medicine and infectious diseases. “But the virus can be devastating for pregnant women because it puts their babies at risk for microcephaly, which causes an abnormally small head and brain and other birth defects. There have been two cases of Zika-related microcephaly in California.”

She said the Zika virus has also been associated with Guillain-Barré syndrome, a rare nervous system disorder that can cause muscle weakness and paralysis. There have been seven cases of Zika-related Guillain-Barré syndrome, according to the CDC.

A new study out of the United Kingdom shows that the Zika virus may harm adult brains as well. The study was conducted with mice and researchers are trying to determine how the findings might apply to humans.

“Right now the results are just too preliminary to draw any conclusions about the human brain,” Dr. Martin said. “We just don’t know what it means yet. The best thing to do at this point is protect yourself from mosquito bites.”

So far what we know is that for the vast majority of people who get the Zika virus and actually experience symptoms, they are generally not serious, Dr. Martin said. Most common are fever, rash, joint pain, and conjunctivitis or pink eye. Symptoms usually appear a few days to a week after being bitten by an infected mosquito or having unprotected sex with an infected partner, she added.

“You generally feel achy and tired,” Dr. Martin said. “Very few people require medical attention, but you should contact your doctor if symptoms are severe.”

Take Precautions

Women who are pregnant or planning to become pregnant should take precautions, according to Dr. Martin. They should avoid traveling to any areas where there are cases of locally transmitted Zika virus, meaning those infected contracted the disease from a mosquito bite they received there.

Women who have traveled to those areas should wait at least eight weeks after returning before trying to become pregnant, she explained. Because the Zika virus can be sexually transmitted, men who have traveled to these areas should also wait eight weeks before trying to conceive. However, men who have contracted the Zika virus should wait six months before having unprotected sex with their partner, she added.

While there is no evidence that mosquitoes are transmitting the Zika virus in California, it’s still important to protect yourself against mosquito bites, especially if you are pregnant or are trying to conceive, or travel to areas where mosquitoes are transmitting the virus, Dr. Martin said. Taking precautionary steps to avoid mosquito bites can also help you avoid West Nile virus, another mosquito-borne illness.

When you are outside, particularly in wooded areas where there tend to be more mosquitoes, Dr. Martin recommends wearing bug repellent that contains DEET, picaradin, oil of lemon eucalyptus, or IR3535. DEET can be used safely on infants and children 2 months old and older. Wear long sleeves and pants when possible.

To keep mosquitoes from coming inside, be sure screens on doors and windows have no tears or holes. It’s also important to get rid of any standing water, where mosquitoes lay their eggs. Drain all sources of standing water in your yard, including buckets, old car tires, rain gutters, birdbaths, flower planters and pet bowls.

Dr. Martin said there is still a lot that is not known about the Zika virus. It is much more prevalent in areas where Aedes mosquitoes are more common such as South America and the Pacific Islands. There has also been an outbreak of locally transmitted Zika in Florida. She encourages pregnant women to check the CDC website to see where the Zika virus is present before traveling.

“Pregnant women are being advised not to travel to those areas,” she added. “We don’t think Zika is a major threat for most people, but we’ll have to see what further research tells us.”

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