Infectious diseases

Virology

Researchers at Roche in Penzberg have successfully developed a test to accurately detect whether a pregnant patient has recently contracted the CMV virus for the first time, or whether the infection is an old one.

Viral diseases represent an insidious and serious risk to health. In many cases, viruses are not detected early enough, allowing them to spread unchecked. Viruses are difficult to track and to treat due to their ability to change very rapidly.

CMV test – a reliable diagnosis for pregnant women

A cytomegalovirus (CMV) infection is usually harmless and generally goes unnoticed. Around 60 percent of all adults are carriers of CMV – without even knowing it.

However, it can be dangerous to contract a CMV infection for the first time during pregnancy. If CMV is passed from mother to child, it may cause severe abnormalities in the unborn. The Roche CMV IgM test detects whether the IgM antibodies in the blood of a pregnant woman are the result of a new or old infection. CMV only poses a risk to the baby if the infection is new. The CMV IgM test provides pregnant patients with a reliable diagnosis and eliminates the unnecessary worry that can be caused by false positive test results.

Immunoglobin M (IgM) is the first class of antibodies to be produced by the immune system in response to a pathogen. High concentrations of IgM therefore indicate an acute infection. These antibodies typically disappear once the acute phase has passed, and are replaced by IgG. In some cases, however, IgM molecules remain detectable in the blood for a long time, and can therefore provide a false indication of an acute infection.

The CMV IgM test developed by the researchers in Penzberg can distinguish between IgM produced at the start of infection and IgM persisting in the later stages, and can therefore specifically target early-phase IgM antibodies. To distinguish between early-phase and late-phase IgM in the blood, the test measures the avidity of the antibodies. This indicates the strength of the binding interactions between antigens and antibodies.