Lower prevalence of congenital cytomegalovirus infection in Portugal: possible impact of COVID-19 lockdown?

Universal and Expanded Screening Strategy for Congenital Cytomegalovirus Infection: Is Pool Testing by a Rapid Molecular Test in Saliva a New Choice in Developing Countries?

BACKGROUND

Several screening strategies for identifying congenital CMV (cCMV) have been proposed; however, the optimal solution has yet to be determined. We aimed to determine the prevalence of cCMV by universal screening with saliva pool testing and to identify the clinical variables associated with a higher risk of cCMV to optimize an expanded screening strategy.

METHODS

We carried out a prospective universal cCMV screening (September/2022 to August/2023) of 2186 newborns, analyzing saliva samples in pools of five (Alethia-LAMP-CMV®) and then performed confirmatory urine CMV RT-PCR. Infants with risk factors (small for gestational age, failed hearing screening, HIV-exposed, born to immunosuppressed mothers, or <1000 g birth weight) underwent expanded screening. Multivariate analyses were used to assess the association with maternal/neonatal variables.

RESULTS

We identified 10 infants with cCMV (prevalence: 0.46%, 95% CI 0.22-0.84), with significantly higher rates (2.1%, 95% CI 0.58-5.3) in the high-risk group (p = 0.04). False positives occurred in 0.09% of cases. No significant differences in maternal/neonatal characteristics were observed, except for a higher prevalence among infants born to non-Chilean mothers (p = 0.034), notably those born to Haitian mothers (1.5%, 95% CI 0.31-4.34), who had higher odds of cCMV (OR 6.82, 95% CI 1.23-37.9, p = 0.04). Incorporating maternal nationality improved predictive accuracy (AUC: 0.65 to 0.83).

CONCLUSIONS

For low-prevalence diseases such as cCMV, universal screening with pool testing in saliva represents an optimal and cost-effective approach to enhance diagnosis in asymptomatic patients. An expanded screening strategy considering maternal nationality could be beneficial in resource-limited settings.

Congenital Cytomegalovirus Testing Outcomes From the ValEAR Trial

OBJECTIVE

To determine the positivity rate of congenital cytomegalovirus (cCMV) testing among universal, hearing-targeted CMV testing (HT-cCMV) and delayed targeted dried blood spot (DBS) testing newborn screening programs, and to examine the characteristics of successful HT-cCMV testing programs.

STUDY DESIGN

Prospective survey of birth hospitals performing early CMV testing.

SETTING

Multiple institutions.

METHODS

Birth hospitals participating in the National Institutes of Health ValEAR clinical trial were surveyed to determine the rates of cCMV positivity associated with 3 different testing approaches: universal testing, HT-cCMV, and DBS testing. A mixed methods model was created to determine associations between successful HT-cCMV screening and specific screening protocols.

RESULTS

Eighty-two birth hospitals were surveyed from February 2019 to December 2021. Seven thousand six hundred seventy infants underwent universal screening, 9017 infants HT-cCMV and 535 infants delayed DBS testing. The rates of cCMV positivity were 0.5%, 1.5%, and 7.3%, respectively. The positivity rate for universal CMV screening was less during the COVID-19 pandemic than that reported prior to the pandemic. There were no statistically significant drops in positivity for any approach during the pandemic. For HT-cCMV testing, unique order sets and rigorous posttesting protocols were associated with successful screening programs.

CONCLUSION

Rates of cCMV positivity differed among the 3 approaches. The rates are comparable to cohort studies reported in the literature. Universal CMV prevalence decreased during the pandemic but not significantly. Institutions with specific order set for CMV testing where the primary care physician orders the test and the nurse facilitates the testing process exhibited higher rates of HT-cCMV testing.

Indirect impact of SARS-CoV-2 pandemic on incidence of maternal primary cytomegalovirus and Toxoplasma gondii infection in pregnancy

OBJECTIVE

Public health interventions promoted during the SARS-CoV-2 pandemic to control viral spread have impacted the occurrence of other communicable disease. Yet no studies have focused on perinatal infections with the potential for neonatal sequelae, including cytomegalovirus (CMV) and Toxoplasma gondii (TG). Here we investigate whether incidence rates of maternal primary CMV and TG infection in pregnancy were affected by the implementation of pandemic-related public health measures.

METHODS

A retrospective study including all pregnant women with confirmed primary CMV or TG infection in pregnancy, managed between 2018 and 2021 at two university centers. The incidence rate was calculated as the number of CMV and TG infections per 100 consultations with a 95% confidence interval (CI). Data were compared between pre-pandemic (2018-2019) and pandemic (2020 and 2021) years. The Newcombe Wilson with Continuity Correction method was employed to compare incidence rates.

RESULTS

The study population included 215 maternal primary CMV and 192 TG infections. Rate of maternal primary CMV infection decreased in 2021 compared with 2018-2019 (4.49% vs 6.40%, attributable risk [AR] 1.92, P = 0.019). By contrast, the rate of TG infection substantially increased in 2020 (6.95% vs 4.61%, AR 2.34, P = 0.006). Close contact with cats was more common among patients with TG infection in 2020 and 2021 than among pre-pandemic TG-infected women (26.3% and 24.4% vs 13.3%, P = 0.013).

CONCLUSION

Pandemic-related public health interventions and associated behavioral and lifestyle changes exerted a divergent effect on the incidence of primary CMV and TG infection in pregnancy, likely due to modulation of exposure to risk factors for these infections.

Pooling Saliva Sample as an Effective Strategy for the Systematic CMV Screening of Newborns-A Multicentric Prospective Study

BACKGROUND

Cytomegalovirus is the most common cause of congenital infections worldwide. Screening all newborns in the first 2 weeks of life is the only way to detect all cases of congenital infection, allowing the monitoring of children with asymptomatic infection at birth and early intervention.

AIM

In this multicenter study, we aimed to evaluate the feasibility of using a saliva pool strategy for mass screening in 7 Portuguese hospitals, and to estimate the current prevalence of this congenital infection in these hospitals.

METHODS

A total of 7033 newborns were screened between June 2020 and June 2022, and 704 pools of 10 saliva samples were analyzed by polymerase chain reaction (PCR).

RESULTS

Of the 704 pools analyzed, 685 were negative and 19 had positive PCR results for cytomegalovirus. After individual PCR testing, 26 newborns had positive saliva results, of which 15 were confirmed by urine testing. Thus, this study's prevalence of congenital infection was 0.21% (95% confidence interval: 0.12%-0.35%).

CONCLUSIONS

In this study, the pooling strategy proved to be effective for the systematic screening of newborns, although this low prevalence raises questions regarding the cost-effectiveness of implementing universal screening. However, this prevalence is probably the result of the control measures taken during the pandemic; therefore, the rates are expected to return to prepandemic values, but only a new study after the pandemic will be able to confirm this.

Congenital cytomegalovirus infection: the state of the art and future perspectives

Congenital cytomegalovirus (cCMV) infection is the most common congenital infection, with an estimated incidence of approximately one in 200 infants in high-income settings. Approximately one in four children may experience life-long consequences, including sensorineural hearing loss and neurodisability. Knowledge regarding prevention, diagnosis, and treatment increased in the recent years, but some challenges remain. In this review, we tried to summarize the current knowledge on both the obstetrical and pediatric areas, while also highlighting controversial aspects and future perspectives. There is a need to enhance awareness among the general population and pregnant women through specific information programs. Further research is needed to better define the classification of individuals at birth and to have a deeper understanding of the long-term outcomes for so defined children. Finally, the availability of valaciclovir medication throughout pregnancy, where appropriate, has prompted the assessment of a universal serological antenatal screening. It is recommended to establish a dedicated unit for better evaluation and management of both mothers and children.

Analysis of an Expanded Targeted Early Cytomegalovirus Testing Program

OBJECTIVE

Determine the detection rate from an expanded targeted early cytomegalovirus (CMV) testing program implemented from a large healthcare system (Intermountain Healthcare, IHC).

STUDY DESIGN

Retrospective review.

SETTING

Tertiary medical center.

METHODS

An electronic system was modified to include indications for testing whenever a provider placed an order for CMV testing. A retrospective analysis of this database was performed.

RESULTS

From March 1, 2021 to August 31, 2022, there were 3450 (8.8%) patients who underwent CMV testing out of 39,245 total live births within the IHC system. Since the formal implementation of this program in 2019, annual CMV testing has increased almost 10-fold: 2668 CMV tests were performed in 2021 compared to 289 CMV tests in 2015. The most frequent indication for congenital CMV (cCMV) testing was small for gestational age (SGA) (68.2%), followed by macrocephaly (13.5%), an abnormal hearing test (5.0%), and microcephaly (4.4%). Fourteen cCMV-infected infants were diagnosed all of them meeting the criteria for symptomatic cCMV. The most common indication resulting in a positive diagnosis was those who presented with SGA (n = 10 patients). The positivity rate would result in a prevalence of 35.7 symptomatic cCMV cases diagnosed per 100,000 live births, numbers comparable to those expected for universal cCMV screening.

CONCLUSION

An expanded targeted early cCMV testing program may improve detection rates of symptomatic cCMV cases and should be considered as a feasible alternative approach to universal or hearing-targeted early CMV testing.

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

This study evaluated the impact of the coronavirus disease 2019 (COVID-19) pandemic on the occurrence of maternal primary cytomegalovirus (CMV) infection in Japan. We performed a nested case-control study using data from maternal CMV antibody screening under the Cytomegalovirus in Mother and infant-engaged Virus serology (CMieV) program in Mie, Japan. Pregnant women with negative IgG antibodies at ≤20 weeks of gestation who were retested at ≥28 weeks were enrolled. The study period was divided into 2015-2019 as the pre-pandemic and 2020-2022 as the pandemic period, and the study site included 26 institutions conducting the CMieV program. The incidence rate of maternal IgG seroconversion was compared between the pre-pandemic (7008 women enrolled) and pandemic (2020, 1283 women enrolled; 2021, 1100 women; and 2022, 398 women) periods. Sixty-one women in the pre-pandemic period and five, four, and five women during 2020, 2021, and 2022, respectively, showed IgG seroconversion. The incidence rates in 2020 and 2021 were lower (p < 0.05) than that in the pre-pandemic period. Our data suggest a transient decrease in the incidence of maternal primary CMV infection in Japan during the COVID-19 pandemic, which could be due to prevention and hygiene measures taken at the population level.

A Prospective Study of Etiology and Auditory Profiles in Infants with Congenital Unilateral Sensorineural Hearing Loss

Congenital unilateral sensorineural hearing loss (uSNHL) is associated with speech-language delays and academic difficulties. Yet, controversy exists in the choice of diagnosis and intervention methods. A cross-sectional prospective design was used to study hearing loss cause in twenty infants with congenital uSNHL consecutively recruited from a universal neonatal hearing-screening program. All normal-hearing ears showed ≤20 dB nHL auditory brainstem response (ABR) thresholds (ABRthrs). The impaired ear median ABRthr was 55 dB nHL, where 40% had no recordable ABRthr. None of the subjects tested positive for congenital cytomegalovirus (CMV) infection. Fourteen subjects agreed to participate in magnetic resonance imaging (MRI). Malformations were common for all degrees of uSNHL and found in 64% of all scans. Half of the MRIs demonstrated cochlear nerve aplasia or severe hypoplasia and 29% showed inner ear malformations. Impaired ear and normal-hearing ear ABR input/output functions on a group level for subjects with ABRthrs < 90 dB nHL were parallel shifted. A significant difference in interaural acoustic reflex thresholds (ARTs) existed. In congenital uSNHL, MRI is powerful in finding a possible hearing loss cause, while congenital CMV infection may be relatively uncommon. ABRs and ARTs indicated an absence of loudness recruitment, with implications for further research on hearing devices.

Impact of the COVID-19 Pandemic on the Diagnosis of Congenital Cytomegalovirus Infection in Spain

We conducted an observational study performed within the Spanish Registry of Children with congenital cytomegalovirus (cCMV) to evaluate the impact of the COVID-19 pandemic on the diagnosis of new cases of cCMV. Our study suggest a significant decrease in the monthly rate of new cCMV diagnoses during the COVID-19 pandemic.