Transient Decrease in Incidence Rate of Maternal Primary Cytomegalovirus Infection during the COVID-19 Pandemic in...

Area of Science:

• Virology
• Maternal Health
• Epidemiology

Background:

• Cytomegalovirus (CMV) is a common virus that can cause complications during pregnancy.
• The COVID-19 pandemic led to widespread implementation of public health and hygiene measures.
• The impact of the pandemic on maternal primary CMV infection rates was previously unevaluated in Japan.

Purpose of the Study:

• To assess the effect of the COVID-19 pandemic on the incidence of maternal primary CMV infection in Japan.
• To compare CMV seroconversion rates in pregnant women before and during the pandemic.

Main Methods:

• A nested case-control study was conducted using data from the Cytomegalovirus in Mother and infant-engaged Virus serology (CMieV) program in Mie, Japan.
• Pregnant women with initial negative IgG antibodies at ≤20 weeks gestation, retested at ≥28 weeks, were analyzed.
• Maternal IgG seroconversion incidence was compared between the pre-pandemic (2015-2019) and pandemic (2020-2022) periods.

Main Results:

• A total of 7008 women were enrolled in the pre-pandemic period, with 61 cases of IgG seroconversion.
• During the pandemic, 1283 women in 2020, 1100 in 2021, and 398 in 2022 were enrolled, with 5, 4, and 5 seroconversions, respectively.
• The incidence rates of maternal IgG seroconversion in 2020 and 2021 were significantly lower (p < 0.05) than in the pre-pandemic period.

Conclusions:

• The study suggests a transient decrease in maternal primary CMV infection incidence in Japan during the COVID-19 pandemic.
• Population-level prevention and hygiene measures implemented during the pandemic may have contributed to the observed reduction in CMV transmission.