Africa: Cmv Infection Can Pass From Mother to Baby During Pregnancy. Here's How to Prevent It

Cytomegalovirus (CMV) is a common infection that can pass from a pregnant mother to her baby during pregnancy. CMV is a preventable cause of childhood disability, making it crucial to raise awareness and take preventative measures. Pregnant women are often advised to avoid certain foods and handle cat litter carefully due to infection risks, but fewer are warned about sharing food, drinks, or utensils with young children. Washing hands after changing diapers or wiping noses can also significantly reduce CMV infection.

CMV spreads through direct contact with body fluids like saliva, nasal mucus, and urine of young children. While it may cause mild flu-like symptoms or no noticeable signs in infected individuals, young children can shed high levels of the virus in their body fluids for extended periods while being asymptomatic. Parents, caregivers, and childcare workers face an increased risk of infection.

In rare cases, a pregnant woman acquiring CMV can transmit the virus to her fetus through the placenta, resulting in congenital CMV infection in about one in 200 babies born to infected mothers. While most babies remain well, the infection can interfere with fetal development, leading to microcephaly, hearing loss, developmental delays, and cerebral palsy.

Diagnosing a CMV infection in pregnant women involves a simple blood test, but until recently, routine testing was not recommended due to a lack of proven treatments to reduce transmission. In 2020, a randomized trial demonstrated that early treatment with the antiviral drug valaciclovir during a woman's first trimester could reduce the risk of fetal CMV infection from 48% to 11%.

Valaciclovir is now offered to women with primary CMV infections in the first trimester to minimize the risk of fetal transmission, ideally beginning within six weeks of infection and by 14 weeks of pregnancy. Although valaciclovir treatment is currently available off-label in Australia, further research is needed to fully understand its benefits and risks, including long-term outcomes for both mothers and babies.

Australian guidelines now recommend early CMV testing for women at greater risk of exposure, particularly those who work with or care for young children. Testing can identify women who have never previously contracted CMV, leaving them susceptible to primary infections during pregnancy with the highest risk to the baby. While Australian guidelines do not yet advocate for universal screening, further research is needed to determine the cost-effectiveness and feasibility of implementing such measures, considering the availability of healthcare resources and workforce capacity in Australia.

In the meantime, pregnant women should receive information on simple hygiene precautions, such as avoiding the sharing of food, drinks, or utensils with children and practicing good hand hygiene after changing diapers or wiping noses, to reduce their risk of CMV infection.