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CMV IgG

CMV IgG: antibodies against a virus passed on through body fluids, including semen

According to the RIVM, cytomegalovirus (CMV) is passed on through contact of mucous membranes with infected body fluids, such as saliva, urine, semen, cervical mucus (mucus from the cervix), blood and breast milk. According to MedlinePlus, antibodies are proteins the immune system makes to fight germs such as viruses, and the body keeps remembering the IgG kind against CMV after the infection.

IgG antibodies against CMV remain detectable for life according to the RIVM, so CMV IgG in the blood points to a past infection. According to the RIVM, someone is contagious during the first infection, with a reinfection and in periods when the virus is active again without symptoms. Whether there is CMV IgG in the blood, only a blood test can show.

Star-SHL and Diagnostiek voor U give 'negative' as the reference value for CMV antibodies, and Unilabs lists 'n.v.t.' (not applicable) as the reference value for CMV IgG.

Doctor's Assessment Included

CMV IgG are antibodies against cytomegalovirus, a herpesvirus that stays latent in the body after an infection. According to the RIVM, IgG stays detectable for life, so a positive result fits a past infection.

Star-SHL and Diagnostiek voor U give "negative" as the reference value for CMV antibodies, without a unit; Unilabs lists "n.v.t." (not applicable) as the reference value for CMV IgG.
According to the RIVM, CMV antibodies formed earlier do not protect against the virus becoming active again or against another type of CMV.
According to the RIVM, pregnant women in the Netherlands are not routinely screened for CMV.

CMV IgG: what this test measures

A CMV IgG test looks for IgG antibodies against CMV in the blood and so says something about a past infection; according to the RIVM, IgM antibodies are detectable for 4 to 6 months after an infection.

CMV IgG: why this value matters

A positive CMV IgG shows that someone has caught cytomegalovirus at some point, even though according to the RIVM a CMV infection usually runs without symptoms. Because the infection usually runs without symptoms, a large part of the population sheds the virus from time to time and no measures are possible, a duty to report CMV makes no sense, according to the RIVM.

CMV IgG: how the blood test works

Referral: No GP referral needed. After the order we arrange the referral through ZorgDomein, within one business day; orders after 17:00 or at the weekend start on the next business day. ZorgDomein emails a barcode, and that barcode is what the draw site needs.
The draw: A blood draw from a vein in the arm, at a partner laboratory's draw site. No home kit, no finger prick.
Where: 650+ draw sites run by independent laboratories across the Netherlands. Draw sites

CMV IgG: when is testing worthwhile?

According to the RIVM, a CMV IgG test is done together with an IgM test to establish a recent first CMV infection in an immunocompetent person, someone whose immune system works normally, and according to the RIVM the disease can be established by a blood test.

CMV IgG: symptoms of a high or low value

Low Levels

According to the RIVM, without detectable CMV IgG an infection can still be in the early, seronegative phase: the period before the antibodies can be found in the blood.

High Levels

A positive CMV IgG points to an infection someone has had at some point; CMV stays latent in the body afterwards, according to the RIVM, and can become active again, with renewed shedding of the virus, which according to the RIVM mostly runs without symptoms with a good immune system.

CMV IgG: causes of a low or high value

What lowers the value

Early phase of an infection

In the early, seronegative phase of a CMV infection, IgG can still be negative.

What raises the value

Past CMV infection

IgG antibodies against CMV appear shortly after the IgM antibodies and then stay detectable for life.
Close contact with young children

Young children in particular shed CMV in large amounts in urine and saliva for a long time, and adults in close contact with young children have a higher risk of becoming infected after all.

CMV IgG: lifestyle and this value

A CMV IgG result is one to talk over with your GP. The RIVM advises avoiding contact with body fluids such as saliva, semen and vaginal mucus and washing the hands after any contact; according to the RIVM, no vaccination against CMV exists.

CMV IgG: frequently asked questions

Is CMV also in semen and vaginal fluid?

Yes, according to the RIVM CMV is in body fluids of people who carry the virus, including semen and vaginal mucus, besides saliva, blood, urine and breast milk.

CMV IgG: sources

RIVM, LCI-richtlijn CMV-infectie, vastgesteld 27 januari 2015, wijzigingen tot 18 maart 2025, lci.rivm.nl, geraadpleegd 2026-10-14 (retrieved 2026) lci.rivm.nl