The mosquito-borne Zika virus is making headlines for its rapid spread through South and Central America, Mexico, Puerto Rico and parts of the Caribbean, including the United States Virgin Islands, since May 2015, as well as its potential link to neurological syndromes.
Also in early February, a Texas health department announced that a woman who had not travelled in the past three weeks has become infected with the Zika virus after having sexual contact with an infected person who had traveled to a Zika-endemic area. This refutes earlier reports that the virus most likely couldn’t be transmitted through person-to-person contact, according to WHO. The CDC has since confirmed that an infected male can pass the virus to his female or male sex partners.
UCHealth disease experts say prevention is paramount to avoiding the disease.
“Although we don’t know all the ways Zika virus disease can manifest, we do know it is largely transmitted by mosquitoes, so preventing mosquito bites when in Zika-endemic areas is very important,” said Dr. Daniel Pastula, neurologist, medical epidemiologist and arboviral disease expert with UCHealth.
The Feb. 2 confirmed case of Zika in the Texas women was the first U.S. case of Zika virus infection in a non-traveler in the continental U.S., according to CDC.
The Zika virus is usually a mild, self-limiting viral disease. Only one in five infected will experience fever, rash, joint pain and conjunctivitis (red eyes) lasting a few days to a week or more.
A major cause for concern with the virus arises from a possible correlation between the virus and neurological birth defects in babies born to infected mothers as well as Guillain-Barre syndrome in others.
Microcephaly is a birth defect in which the baby’s head is much smaller than expected.
“Microcephaly is usually associated with poor brain development; the brain and fetus don’t develop properly,” said UCHealth’s Dr. David Beckham, an associate professor of medicine in the Division of Infectious Diseases at University of Colorado School of Medicine. Beckham also directs the neurological infection fellowship program at CU. “It’s a syndrome, and one cause is infection — the cytomegalovirus being the most common. It’s a relatively rare birth defect, so having so many cases in Brazil, at the same time as this (Zika) outbreak, is why it’s concerning.”
Because of the possible connection, the CDC put out a level two alert, recommending travelers take enhanced precautions if traveling to areas where Zika virus transmission is ongoing. In addition, it recommends that pregnant women or those planning to become pregnant consider postponing travel to those areas. This recommendation includes the male sexual partners of these women because Zika can be sexually transmitted. Pregnant women or those planning to become pregnant should refrain from sex for several weeks, or use a condom, with a sexual partner who has traveled to a Zika-endemic area. Visit CDC.gov/zika for the most updated precautions.
“Currently, there are no disease modifying therapies or a vaccine for the virus, and therefore prevention is key,” Pastula said. “To prevent Zika and other mosquito-borne viral diseases such as dengue and chikungunya, you need to prevent mosquito bites.”
Pastula recommends that people:
- Wear insect repellent. Use EPA-registered repellents containing DEET, picaridin, oil of lemon eucalyptus or IR3535, according to the CDC. Most repellents, including DEET, can be used on children older than two months.
- Wear long sleeves and pants. Cover exposed skin by wearing long-sleeved clothing. The CDC also recommends using permethrin-treated clothing and gear, such as boots, pants, socks and tents.
- Use screens or close the windows and use air-conditioning while indoors.
- Visit CDC.gov for the most up-to-date guidelines and travel alerts.
The Zika virus is transmitted by only a few types of mosquitoes, found mostly in tropical and subtropical parts of the world. The Aedes species known to carry the virus are not known to live in Colorado, Pastula said.
The CDC recommends Zika virus testing — done by a blood draw — only for people who have traveled to one of the Zika-affected areas recently AND are feeling symptoms.
“Patients who are concerned should talk with their OB/GYN or primary care physician,” Pastula said.
UCHealth experts are currently in the process of working with several different groups, including the CDC, to develop models to study the potential link for fetal infections associated with Zika virus, Beckham said.
“Our goal is to understand how the virus — if it is invading the fetus — is getting there so that we can prevent that from happening,” he said. “We can do those studies much more easily in a lab and take treatment or vaccine approaches to see if we can stop the virus from getting to the fetus.”
Those doctors also are working with another group at Children’s Hospital that is studying a cohort of patients, including infected mothers in Guatemala, to learn more about the virus’ effects.