Zika Virus Infection and Pregnancy

Definition

A Zika infection is caused by a virus. It is often passed from an infected mosquito. It may cause flu like symptoms in some, but does not cause symptoms in most people. It can cause serious problems and birth defects in babies who are still in the womb.

Causes

A specific type of mosquito can pick up Zika when it bites a person with the infection. The mosquito can then pass the virus to the next person it bites. Most Zika infections pass this way.

Zika can also pass from person to person. It may pass:

• During sex when one partner has an active Zika infection
• To an unborn baby if the mother had Zika during or just before pregnancy

Risk Factors

The risk is greater in those who have spent time in a high risk place without mosquito protection. Zika happens in:

• South America, mostly Brazil; Colombia, Bolivia, Ecuador, French Guiana, Guyana, Paraguay, Suriname, and Venezuela
• Mexico and Central America, mostly Guatemala, El Salvador; Honduras, and Panama
• The Caribbean, mostly Barbados, Dominican Republic, Guadeloupe, Haiti, Martinique, Puerto Rico, and Saint Martin
• Southeast Asia and the Pacific Islands
• Africa

Symptoms

Symptoms do not always happen. If they do, they may show up a few days after the bite. These problems may last a few days to a week:

• Fever
• Rash
• Eye redness and irritation
• Headache
• Joint and muscle pain

Zika infection in pregnant women may cause these problems for the baby:

• Microcephaly—a small head due to poor growth of the brain
• Brain defects
• Eye problems
• Hearing loss
• Slow growth
• Muscle stiffness and spasms
• Seizures
• Joints that are not normal

Diagnosis

The doctor will ask about any recent exposure to Zika from travel or sex.

Blood and urine tests may be done to confirm Zika. Tests will look for the virus or signs that the body has fought the virus. It may be given to pregnant women who:

• Are at risk and have symptoms of Zika
• Have not had symptoms of Zika but who are at risk
• May have been exposed and have had abnormal ultrasounds during pregnancy

A woman with a positive test may be referred to a maternal fetal medicine or an infectious diseases specialist. Those with an abnormal ultrasound will be referred to a maternal fetal specialist.

Treatment

Medicine cannot treat Zika. Symptoms should pass on their own in a week. Rest and fluids can help.

Acetaminophen may be given to ease fever or pain. Nonsteroidal anti-inflammatory drugs (NSAIDs) and aspirin can cause problems in women who may also have dengue infection. NSAIDs should not be used until dengue infection is ruled out.

If a mosquito bites a person who is infected, it can pass the infection to someone else. Steps will be needed to avoid mosquito bites for about a week.

Family Planning

The Zika virus may stay in the body or in sperm for a short time even after symptoms go away. To lower the risk of passing the virus to a new fetus:

• Women who have been infected or suspect an infection should wait at least 8 weeks before trying to get pregnant.
• Men who have been infected or had possible exposure to Zika should wait at least 3 months before trying to have a child with their partner.

Prevention

People who are pregnant or trying to become pregnant should not travel to places where Zika is spreading.

Those who are pregnant and live in areas with ongoing Zika transmission should:

• Take steps to avoid mosquitoes
• Not have sex, OR
• Correctly use condoms with each act of vaginal, anal, or oral sex