CHICAGO — It’s a common, usually harmless virus. But in a rare, unlucky set of circumstances, it can be devastating for infants whose mothers become infected during pregnancy.
Brain damage, deafness, and other birth defects are among potential problems when women inadvertently transmit the virus in the womb. Because those complications are so rare, most people have never heard of CMV — short for cytomegalovirus.
Infectious-disease specialists, parents of affected children and, now, some legislators, are trying to spread awareness about the virus.
Erica Steadman learned about CMV when her daughter Evelyn was born with a small head and probable brain damage last year. Evelyn is deaf and potentially faces developmental problems.
‘‘It’s pretty devastating to us. I did everything I was supposed to do when I was pregnant to make sure she was healthy and I didn’t know about this one thing,’’ said Steadman. ‘‘We have to face the consequences of that.’’
CMV is related to germs that cause genital herpes, cold sores, and chickenpox. It spreads by exposure to body fluids from an infected person. Infections are usually silent but can also cause sore throats and fatigue.
However, the virus can be serious for people with weakened immune systems, including HIV-infected patients and organ transplant recipients. It can also interfere with prenatal brain growth.
The chances of getting infected while pregnant are small, and the chances of passing along the virus in utero are even smaller. Of about 4 million annual US births, about 30,000 babies — less than 1 percent — are born with a CMV infection. About 5,000 of those babies will have CMV-related permanent problems.
The first law in the nation to require a CMV awareness campaign took effect last July in Utah. It requires urine or saliva tests in newborns who fail already required hearing tests. Studies suggest early treatment with antiviral medicine may limit hearing loss and may benefit the child’s development.
Lawmakers in Illinois and Connecticut introduced similar bills this year. These efforts signal ‘‘a very exciting potential shift’’ in thinking about congenital CMV, said Dr. Gail Demmler-Harrison, a CMV specialist at Texas Children’s Hospital in Houston.
Evidence indicates doctors do not often mention CMV to pregnant patients; that gap led to Utah’s law. It was sponsored by state Representative Ronda Menlove, whose 3-year-old granddaughter has CMV-caused deafness.
About 50 Utah newborns have had CMV tests so far; nine tested positive, said Stephanie McVicar, director of newborn hearing screening for Utah’s health department.
Farah Armstrong of Katy, Texas, joined advocates for Connecticut’s proposed law after her 2-week-old daughter, Maddie, died from severe CMV complications in February.
‘‘This is something that no mother should ever have to face,’’ Armstrong wrote in testimony supporting th e bill, which did not get approved before the legislative session ended this month.
The Illinois measure stalled this year because of opposition from the Illinois State Medical Society, which called newborn CMV testing a bid to legislate doctors’ jobs. State Representative Elaine Nekritz, the bill’s sponsor, declared partial win because ‘‘we got the word out.’’
The CDC recommends hygiene measures that may reduce the chances of getting
infected. These include not sharing food, utensils, or toothbrushes used by young children.