This article originally appeared on the Fort Worth Moms Blog on February 8, 2016. Since then, the CDC released more information about the Zika virus and its effects on pregnancy. Dr. Catherine Bevan, local mom and OBGYN, shared the following updated information with the Fort Worth Moms Blog so that our readers can be in the know and aware of safety precautions this summer.
The fervor over Zika virus is at an all-time high. As we get closer to the upcoming Summer Olympic Games in Rio de Janeiro, we are also dealing with the inevitability of the first locally transmitted case here in the United States. Pregnant women, their partners, and couples attempting to conceive are especially concerned given the recent announcement that there is enough evidence to conclude that Zika virus infection in the fetus can lead to poor pregnancy outcomes including microcephaly and pregnancy loss. Just this week, new research down I-30 at UT Southwestern in Dallas showed that Zika virus directly infects the premature brain of the fetus, where it evades immune system detection, and replicates in the developing neurons.
Meanwhile, the Centers for Disease Control and Prevention (CDC) recently issued its “Zika – CDC Draft Interim Response Plan,” a document outlining how states and the nation should prepare and respond to Zika virus within the United States. As of June 9, the most recent date data were reported, 234 pregnant women in the U. S. have shown laboratory evidence of Zika infection. Of these, there have been six reported poor outcomes (three cases of microcephaly and three cases of pregnancy loss).
Currently, all local cases of Zika virus infection have been acquired abroad (primarily from Latin America and the Caribbean), but most experts believe that it is only a matter of time before the virus is transmitted locally. Since the mosquito that transmits Zika virus, Aedes aegypti, is widespread across Texas, it’s possible that local transmission could occur here.
The CDC has several recommendations for pregnant women and for women who may become pregnant.
If you are pregnant:
- Avoid travel to an area with Zika – if you must travel to an area with Zika virus, strictly follow point #2.
- Take steps to prevent mosquito bites – long-sleeved shirts and pants, air conditioning, insect repellants.
- Take steps to prevent getting Zika through sex – use a condom or abstain from sex if your male sex partner is at risk of Zika virus infection.
- See a doctor or other healthcare provider – especially if you travel to an area with Zika virus.
- Zika Prevention Kit – The CDC has released a document (http://www.cdc.gov/zika/pdfs/zika-kit-flyer.pdf) to help women prepare a “Zika Prevention Kit.”
In February 2016, Fort Worth Moms Blog owner Emily Y interviewed Dr. Catherine Bevan, about the cranial deformity known as microcephaly. This developmental issue is a hot topic thanks to its connection with the Zika virus. Dr. Bevan not only answered our questions about microcephaly and its relationship with Zika, but she also addressed other known causes, detection, and treatment.
1. What is microcephaly?
Microcephaly, which literally means “small head,” is loosely defined as a head circumference more than two standard deviations (SD) below the mean for a given age, sex, and gestational age. Most doctors classify microcephaly as “borderline,” “moderate,” or “severe” based on how far the head circumference falls below the mean, and as “congenital” or “postnatal” based on if it is present at birth or develops later in life. It is important to note that microcephaly is not a diagnosis, but rather, a sign that may or may not be indicative of abnormal brain development. Many individuals with microcephaly have normal brain development and live normal lives. For example, about 2 percent of the population would be classified as microcephalic just because their heads are at the low end of the normal population distribution.
2. How does a person acquire microcephaly?
As previously stated, microcephaly is not a specific diagnosis, and therefore, has a myriad of causes. Both genetic abnormalities and a variety of environmental insults can affect brain development, resulting in microcephaly. There are several rare genetic abnormalities that can affect brain development, and their discussion is probably beyond the scope of this question. Of more interest are the environmental factors that may cause microcephaly. Infections acquired during pregnancy may affect the fetus’ central nervous system. Examples include bacteria such as syphilis and viruses such as HIV and herpes. Zika virus infections have been confirmed in several infants with microcephaly, but the connection between the two isn’t fully understood. Other environmental factors include in utero drug or toxin exposure, malnutrition, or insults that cause a lack of oxygen delivery to the brain. Approximately 40 percent of cases of microcephaly have an unknown origin.
3. How is microcephaly detected? How early can it be detected?
Most cases of microcephaly are detected after birth, during routine pediatric care visits. A single measurement of head circumference below two or three standard deviations of the mean should prompt further evaluation, especially when accompanied by abnormal development. The objective of further evaluation is to determine if the microcephaly is a sign of underlying brain developmental issues. The work-up is highly based on the patient’s history, but may include genetic testing or imaging studies of the brain, such as MRI.
Just as there are growth curves for newborns and toddlers, there are growth curves for the developing fetus. Ultrasound examination during pregnancy routinely measures the fetus’ head circumference and these measurements are compared to prenatal growth curves. This comparison is complicated by the accuracy limitations of ultrasound and the fact that the fetal growth curves are not as reliable as the postnatal growth curves. An obstetrician would carefully consider the entire case and all available data before deciding to perform any additional testing before birth.
4. Are there any treatments for microcephaly — in utero or out?
Treatment is highly dependent of the individual case. After birth, prompt detection and referral to a specialist (pediatric neurologist, pediatric infectious disease specialist, etc.) would be the most helpful. In the cases of microcephaly due to infections acquired during pregnancy or due to drugs/toxins, treating the infection and/or stopping the drug may allow the fetus’ brain to develop normally.
5. What disabilities does microcephaly cause after birth, throughout life?
As stated earlier, many individuals with microcephaly have normal brains and live normal lives. The disabilities caused depend on the type of underlying brain abnormality, if any. They could range from mild mental retardation, learning disability, etc. to severe neurologic issues. Unfortunately, some of the brain disorders lead to death early in life.
6. How can mothers protect children from microcephaly?
The best way to protect yourself from microcephaly is to receive prenatal care and follow the recommendations of your obstetrician. This includes avoiding drugs, alcohol, and smoking. As we continue to learn more about the Zika virus, the CDC and the American College of Obstetrics and Gynecology continue to update guidelines and recommendations. Currently, they recommend avoiding exposure to mosquitos. If possible, pregnant women should avoid traveling to areas where Zika outbreaks are ongoing. Precautions to avoid mosquito bites include using EPA-approved bug spray with DEET, covering exposed skin, staying in air-conditioned or screened-in areas, and treating clothes with permethrin. These are all considered safe in pregnancy. Also, because there have been reported cases of Zika virus that were spread through sexual transmission, men who have traveled to an area of active Zika virus should use condoms or abstain from intercourse with their pregnant partners.
Precautionary Steps
If you are planning on having children and have possibly been exposed to Zika via recent travel or sex without a condom, the CDC recommends waiting before trying to conceive:
- For women with or without symptoms of Zika virus infection, it is recommended to wait at least 8 weeks after exposure (or onset of symptoms) before trying to get pregnant.
- For men, if symptoms of Zika infection are present, it is recommended to wait at least 6 months after symptoms start (it is unknown how long the virus is present in sperm).
- For men without symptoms, wait at least 8 weeks after exposure before trying to get pregnant.
With the threat of Zika virus looming and the relative uncertainty over its public health impact, it is easy to get wrapped up in the media hype and fear-inducing headlines. It is important to remember that with a measured, logical approach, the risk to yourself and any potential fetus is still quite low. Address any questions or concerns that you may have with your healthcare provider, and as you enjoy another hot Texas summer, don’t forget to protect yourself and your partner from mosquitos.
Dr. Catherine Bevan is a board certified obstretician and gynecologist, who practices in Tarrant County, with offices in Fort Worth and Willow Park. She is a Fort Worth native and received her Bachelor of Arts degree from Washington University in St. Louis where she graduated cum laude, Phi Beta Kappa. She then returned to Texas to complete her medical degree at UT Southwestern as well as her residency training at Parkland Memorial Hospital. She also spent an additional year as an assistant professor at UT Southwestern, specializing in gynecologic surgery and emergency women’s care. Providing excellent service to her patients is a passion for her as she guides them to the best possible healthcare outcomes.
You can read more from Dr. Bevan on the Fort Worth Moms Blog archives.
Please visit her websites for more information: www.healthcareoftexas.com and www.txhealthcare.com.
You can contact Dr. Bevan at:
- 1250 8th Avenue, Ste 320 // Fort Worth, TX 76104 // (P) 817-924-2111 // (F) 817-564-3980
- 134 El Chico Trail, Suite 103 // Willow Park, TX 76087 // (P) 817-441-1644 // (F) 817-441-1626
