Cytomegalovirus (CMV) seroprevalence among US children aged 1–5 years was 28.2% during 2017–2018 in the National Health and Nutrition Examination Survey (NHANES) [1]. Here, we provide updated estimates of CMV immunoglobulin G (IgG) seroprevalence using the larger NHANES 2017–March 2020 pre-pandemic dataset.

A multiplex real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) assay for detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was developed based on the same primer and probe sequences of an existing U.S. CDC Emergency Use authorized test panel, targeting SARS-CoV-2 N1, N2 and human RNase P genes in singleplex. Both singleplex and multiplex assays demonstrated linear dynamic ranges of 8 orders of magnitude and analytical limits of detection of 5 RNA transcript copies/reaction. Both assays showed 100% agreement with 364 previously characterized clinical specimens (146 positive and 218 negative) for detection of SARS-CoV-2 RNA. To further increase testing throughput, 40 positive and 20 negative four-specimen pools were tested by the multiplex assay and showed 97.75% and 100% congruence with individual specimen tests, respectively. rRT-PCR assay multiplexing and sample pooling, individually or in combination, can substantially increase throughput of SARS-CoV-2 testing.

Dear Editor, Petersen et al reported that cytomegalovirus (CMV) seroprevalence among U.S. children aged 1–5 years in the National Health and Nutrition Examination Survey (NHANES) increased from 20.7% in 2011–2012 to 28.2% in 2017–2018, with significant increases among 1-year-olds, non-Hispanic White children, those living at or above the poverty level, and being the only child ≤5 years in the household [1]. As we previously reported, 2011–2012 NHANES results indicated that these groups had significantly lower CMV seroprevalence in comparison to children that were older, Hispanic, living below the poverty level, and living with another child ≤5 years in the household, respectively [2, 3].

Cytomegalovirus (CMV) seroprevalence among U.S. children 1-5 years-old was assessed in the National Health and Nutrition Examination Survey 2011-2012. Overall seroprevalence (95% confidence interval) of IgG was 20.7% (14.4-28.2%), IgM 1.1% (0.4-2.4%), and low IgG avidity 3.6% (1.7-6.6%), corresponding to a 17.3% (10.1-26.7%) prevalence of recent infection among IgG-positive children.