Awareness of cytomegalovirus and risk factors for susceptibility among pregnant women, in Montreal, Canada

Estimated cytomegalovirus seroprevalence in the general population of the United States and Canada

Seroprevalence data for cytomegalovirus (CMV), a widespread virus causing lifelong infection, vary widely, and contemporary data from the United States (US) and Canada are limited. Utilizing a modeling approach based on a literature review (conducted August, 2022) of data published since 2005, we determine age-, sex-, and country-specific CMV seroprevalence in the general US and Canadian populations. Sex-specific data were extracted by age categories, and a random-effects meta-regression model was used to fit the reported data (incorporating splines for the US). Seven studies reported US CMV seroprevalence (both sexes, aged 1‒89 years); all used National Health and Nutrition Examination Survey data. Due to limited population-based studies, Canadian estimates were modeled using other limited country data. In both countries, modeled seroprevalence estimates increased with age and were higher in females versus males (US: 49.0% vs. 41.6% at 18‒19 years; 61.5% vs. 50.0% at 38‒39 years; Canada: 23.7% vs. 13.7% at 18‒19 years; 32.6% vs. 22.6% at 38‒39 years). Notably, by young adulthood, one-half of US and one-quarter of Canadian females have acquired CMV. The observed differences in CMV seroprevalence in the US and Canada may partially reflect variations in general population characteristics.

Seroprevalence of Anti-Cytomegalovirus Antibodies in Pregnant Women from South-West Romania

Cytomegalovirus (CMV), in addition to other agents, is part of the TORCH complex (Toxoplasma gondii, Rubella virus, Cytomegalovirus, Herpes simplex viruses, and other agents). CMV infection is the most frequent cause of congenital malformations. This study aimed to establish the variation of prevalence of anti-CMV antibodies in pregnant women from the South-West region of Romania, according to demographic factors, such as age and area of residence, in two separate time periods (2013-2016 and 2019-2022). We collected from the hospital records the age, place of residence, and anti-CMV antibody test results using immune electrochemiluminescence and chemiluminescence. This study found that the seroprevalence of anti-CMV IgM antibodies increased slightly from 2013-2016 to 2019-2022, from 1.92% to 2.26%, and for IgG antibodies from 93.68% to 94.96%. In both groups was observed a descending trend of anti-CMV IgM seroprevalence with an increase in age, showing a decrease in seroprevalence from 3.57% to 1.09% in pregnant women from rural areas in the 31-35 years age group, while in urban areas, we observed a decrease in seroprevalence from 11.11% to 3.06% in the <20 years age group. The IgG seroprevalence showed an increase both in rural areas (from 93.97% to 95.52%) and urban areas (from 93.52% to 94.27%). In both groups, seroprevalence was higher in rural areas compared to urban regions. These results show a high rate of immunization against CMV in pregnant women in South-West Romania, which led to a low risk of acquiring the primary infection during pregnancy. However, the increase in the rate of primary CMV infections in pregnancy suggests the need for prioritizing screening programs and improving the existing protocols to enhance maternal and child healthcare.

Knowledge of cytomegalovirus and available prevention strategies in pregnancy: a cross-sectional study in Portugal

OBJECTIVE

Maternal and fetal congenital infection by cytomegalovirus (CMV) during pregnancy is the leading infectious cause of neurologic impairment and hearing loss. Efforts at limiting CMV exposure are based on hygienic measures. This study assessed the relationship between CMV knowledge and pregnant women's time perspective as per the Zimbardo Time Perspective Inventory (ZTPI) scale.

METHODS

We conducted a prospective descriptive study at a secondary-care Portuguese hospital between October to November 2021. All consecutive pregnant women in antenatal third-trimester appointments were included. The questionnaire included: sociodemographic data, knowledge about CMV, and the ZTPI scale, validated to our population. The number of correct answers in the knowledge section of the questionnaire was tallied to determine the individual knowledge score (KS). We investigated patients subjective perceptions of CMV infection during pregnancy, CMV knowledge, and CMV serologic status of pregnant women.

RESULTS

We enrolled 96 pregnant women. 81.0% had not previously heard about CMV and only 8.8% had heard about it through their obstetrician. No significant association between awareness of CMV and education level was detected. 16.0% of pregnant women declared that they were aware of the hygienic measures for CMV. The CMV serology was performed in 21.3% of those enrolled in the preconception assessment, and 13.8% proved to be immune. From the time perspective, half of the women displayed a future-oriented attitude. Future-oriented women had significantly higher KS. No significant association was found between KS and education level, age, or previous pregnancy. There was a significant association between KS and women that work in health care.

CONCLUSIONS

Most patients had no knowledge of CMV. Being a medical professional and having a future-oriented outlook increases knowledge about CMV. Primary health care and obstetrics doctors may play a crucial role in informing pregnant women of antenatal appointments. The CMV serology coverage is scarce in this sample. This study constitutes a first step toward raising the awareness of the general population about CMV.

Learning from the experiences of pregnant women participating in a research study investigating human cytomegalovirus shedding: A qualitative study

Transmission of human cytomegalovirus (CMV), from a pregnant woman to her fetus can cause congenital CMV infection, with life-long problems in some infected children. The presence of CMV in an infected individual's bodily fluid is known as shedding. An individual can become infected with CMV through contact with another individual who is shedding CMV in their bodily fluid, and the avoidance of contact with infected fluids may reduce the risk of infection. We explored the experiences of pregnant women taking part in a study investigating CMV shedding, to identify the potential facilitators and barriers towards engaging pregnant women with CMV risk-reduction measures. Twenty pregnant women participated in semi-structured, end-of-study, telephone interviews, analysed using thematic analysis. They participated in an observational study investigating CMV shedding in pregnant women previously infected with CMV living with young children. Participating women considered that CMV testing of themselves and their newborns was a benefit of participation, without raising additional concerns. They identified that their participation was contingent on a balance of convenience and inconvenience, and benefits and risks. Participation increased their awareness of their hygiene-based practices, leading to behavioural modifications that put them in contact with urine and saliva of their children without instructions to do so. These behavioural modifications might interfere with household routines. However, they recognised it to be a time-limited risk-reduction measure, and felt empowered by the knowledge they had gained through study participation and the support they had received from their partners. Participating women gained an increased awareness of their behaviour, resulting in behavioural modification without instructions to do this, in line with previous findings that trial participation can impact on participants' thinking about their behaviour with a possibility to influence change. Maternal research and risk-reduction measures should be centred around being informative, convenient, empowering, and supportive.

Congenital Cytomegalovirus and Hearing Loss: The State of the Art

In developed countries, congenital cytomegalovirus (cCMV) infection is the most common congenital viral infection, representing the leading non-genetic cause of sensorineural hearing loss (HL). Diagnosis of cCMV infection can be performed by detection of CMV DNA in urine or saliva within 2-3 weeks after birth, or later in dried blood samples on the Guthrie card. Currently, there are many controversies regarding the preventive, diagnostic, and therapeutic approaches to cCMV infection. HL secondary to cCMV is highly variable in onset, side, degree, audiometric configuration, and threshold changes over time. Therefore, it is of paramount importance to perform a long and thorough audiological follow-up in children with cCMV infection to ensure early identification and prompt treatment of progressive and/or late-onset HL. Early cochlear implantation appears to be a valid solution not only for children with bilateral profound HL, but also for those with single-sided deafness, improving localization ability and understanding speech in noisy environments. Moreover, the decision to apply a unilateral cochlear implant in children with cCMV is strengthened by the non-negligible possibility of hearing deterioration of the contralateral ear over time.

Cytomegalovirus seronegativity rate in pregnant women and primary cytomegalovirus infection during pregnancy in rural Germany

BACKGROUND

Congenital cytomegalovirus (CMV) infection is the most common congenital infection worldwide and one of the leading causes of congenital hearing loss in newborns. The aim of this study was to determine the seroprevalence rate for cytomegalovirus in pregnant women and the rate of CMV serological testing utilised during pregnancy in a rural region in Germany.

METHODS

Retrospective data on the prevalence of CMV IgG and IgM antibodies were obtained from 3,800 women, identified in the study group of 19,511 pregnant women from outpatient settings whose samples were collected between 1 and 2014 and 30 April 2018. In addition, the serological CMV status in regards to various billing methods was further analyzed.

RESULTS

Serological CMV tests were performed in 3,800 (19.5%) out of 19,511 pregnant women. 2,081 (54.8%) of these women were CMV seronegative. Among those, seroconversion rate of 0.37-1.42% was identified. A proportion of 2,710 (14.7%) of all 18,460 women with statutory health insurance made use of the CMV testing as an individual health service.

CONCLUSIONS

The low uptake of CMV serological testing in the study population covered indicates low risk awareness among pregnant women and their healthcare professionals. Presented seronegativity rates and routine seroconversion rate, demonstrate importance to improve intervention strategy to prevent feto-maternal CMV transmission.

Cross-sectional study to assess awareness of cytomegalovirus infection among pregnant women in Germany

BACKGROUND

Study aimed to assess awareness of congenital cytomegalovirus (CMV) infection and its determinants in pregnancy.

METHODS

Cross-sectional survey was conducted in five hospital-based maternity units in Germany. Pregnant women attending the maternity departments completed interviewer/self-administered survey questionnaire. High-risk group was defined according to contact with children under five years of age (at home or at work). Quantitative analyses using multivariable logistic regression were performed.

RESULTS

One thousand two hundred thirty-three pregnant women were included. 48.5% (n = 598) of women reported any knowledge about risk of CMV infection during pregnancy. CMV infection was less known than other infections or diseases (education about toxoplasmosis 95.5% (n = 1,177), listeriosis 60.5% (n = 746). 38% (n = 468) of participants received education about CMV. CMV awareness was associated with the level of education and employment in childcare or medical care. Only 32% (n = 394) of the women made use of serological screening for CMV during pregnancy (individual health service). 40.8% (n = 503) of pregnant women were classified as high-risk group. They had significantly higher knowledge and education about CMV, and msignificantlycant more often use of the serological screening.

CONCLUSIONS

Less than half of pregnant women surveyed were aware of potential risk associated with CMV infection during pregnancy. In our study,one-third third of pregnant women made use of the serological screening for CMV. Regarding the lack of current consensus on the role of serological CMV screening for pregnant women, hygiene preventive measures are the only evidence-based recommendation for pregnant women and knowledge increase could potentially have major public health impact.

A systematic literature review of the global seroprevalence of cytomegalovirus: possible implications for treatment, screening, and vaccine development

Background

Cytomegalovirus (CMV) is a common pathogen that affects individuals of all ages and establishes lifelong latency. Although CMV is typically asymptomatic in healthy individuals, infection during pregnancy or in immunocompromised individuals can cause severe disease. Currently, treatments are limited, with no prophylactic vaccine available. Knowledge of the current epidemiologic burden of CMV is necessary to understand the need for treatment and prevention. A systematic literature review (SLR) was conducted to describe the most recent epidemiologic burden of CMV globally.

Methods

Medline, Embase, and LILACS were searched to identify data on CMV prevalence, seroprevalence, shedding, and transmission rates. The SLR covered the time period of 2010–2020 and focused geographically on Australia, Europe, Israel, Japan, Latin America (LATAM), and North America. Studies were excluded if they were systematic or narrative reviews, abstracts, case series, letters, or correspondence. Studies with sample sizes < 100 were excluded to focus on studies with higher quality of data.

Results

Twenty-nine studies were included. Among adult men, CMV immunoglobulin G (IgG) seroprevalence ranged from 39.3% (France) to 48.0% (United States). Among women of reproductive age in Europe, Japan, LATAM, and North America, CMV IgG seroprevalence was 45.6-95.7%, 60.2%, 58.3-94.5%, and 24.6-81.0%, respectively. Seroprevalence increased with age and was lower in developed than developing countries, but data were limited. No studies of CMV immunoglobulin M (IgM) seroprevalence among men were identified. Among women of reproductive age, CMV IgM seroprevalence was heterogenous across Europe (1.0-4.6%), North America (2.3-4.5%), Japan (0.8%), and LATAM (0-0.7%). CMV seroprevalence correlated with race, ethnicity, socioeconomic status, and education level. CMV shedding ranged between 0% and 70.2% depending on age group. No findings on CMV transmission rates were identified.

Conclusions

Certain populations and regions are at a substantially higher risk of CMV infection. The extensive epidemiologic burden of CMV calls for increased efforts in the research and development of vaccines and treatments.

Trial registration

N/A.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-13971-7.

Congenital cytomegalovirus awareness and knowledge among health professionals and pregnant women: an action towards prevention

INTRODUCTION

Cytomegalovirus (CMV), is a major cause of childhood disabilities and consensus recommendations emphasize the importance of hygienic measures to reduce perinatal infection.

OBJECTIVE

To evaluate the level of awareness about CMV among health professionals and pregnant women.

METHODS

We submitted a 20-item online survey regarding CMV perinatal infection to all obstetricians and midwives in Catalonia (Spain) and a 7-item lay-version of the questionnaire to 700 pregnant women. Levels of knowledge were compared among groups.

RESULTS

Of the 1449 health professionals approached, 338 surveys were answered. 72% of professionals considered CMV a relevant problem. 47% of obstetricians and 28% of midwives (p=<0.001) routinely informed pregnant women, and less than half knew the risk of fetal transmission. We observed significant differences in knowledge between obstetricians and midwives concerning the risks of recurrent infections, risk of transmission, and risk of severe infection (60.7% vs 45.6%, p=0.006 and 50.6% vs 22.5% p=<0.001); and regarding maternal and neonatal symptoms, and newborn sequelae (23% vs. 8.8% p=<0.001). Of the 700 women approached, we obtained a response rate of 72%. Only 23% had previously heard about CMV; 22% identified transmission routes, and 15% preventive measures. Compared to women without risk factors for CMV infection women at greater risk had heard more about CMV [mothers of children <3 years: 36% vs. 20% p< 0.001; occupational exposure: 43% vs. 20% p=<0.001] and had received more information (mothers of children <3 years: 18% vs. 9.5% p=<0.001; occupational exposure: 23% vs. 9.3% p=0.001).

CONCLUSIONS

Health care professionals have limited knowledge about CMV and may fail to enforce preventive measures. While pregnant women have limited awareness about CMV infection, they recognize the need for information. Health campaigns should be promoted to enhance awareness about this perinatal infection.

Experiences of pregnant women and healthcare professionals of participating in a digital antenatal CMV education intervention

Objective

The study aimed to explore the perspectives of participating pregnant women and Health Care Professionals (HCPs) towards receiving and providing cytomegalovirus (CMV) education so that barriers and facilitators towards incorporating CMV in routine antenatal care could be better understood.

Design

This process evaluation phase employed a qualitative design using individual, semi-structured, face-to-face interviews.

Setting

Recruitment and interviews took place within a large teaching hospital from an ethnically diverse area of South-west London

Participants

The study sample included 20 participants: 15 pregnant women, and five HCPs. All participants were involved in a single centre randomized controlled trial of a digital CMV educational intervention in pregnancy.

Findings

Pregnant participants expressed a strong desire to receive information about CMV as part of routine antenatal care. Although HCPs were accepting of the need for CMV education, it was evident that they felt unequipped to provide this; reasons included lack of time, uncertainty about clinical pathways and concern about the potential emotive impact of CMV education. Pregnant women suggested that expressing behaviour changes as risk reduction rather than prevention, made the behaviours feel more achievable and realistic. The support of partners was considered a key factor in the successful adoption of behavioural changes by pregnant women.

Key conclusions and implications for practice

There is an onus on HCPs to consider how CMV can be included as part of antenatal education, with messaging framed as risk reducing rather than prevention.

Knowledge of congenital CMV, risk behaviours for CMV acquisition, and acceptance of an educational infographic among postpartum women: a pilot study

Congenital cytomegalovirus (cCMV) infection in the newborn can present with sensorineural hearing loss and microcephaly. The objectives of this study were to determine baseline knowledge of cCMV and the acceptability of an infographic about cCMV among a group of postpartum women. Participants completed a questionnaire assessing their perceptions of an infographic as well as their knowledge and risk behaviours for acquisition of CMV. Of all 140 respondents, 119 (85%) had no prior knowledge of cCMV, and all 12 women (8.6%) who viewed the infographic indicated that it was helpful. Our study also demonstrated that passive dissemination of an infographic in clinics results in limited viewership.

Guideline No. 420: Cytomegalovirus Infection in Pregnancy

OBJECTIVE

To provide an update on current recommendations for cytomegalovirus (CMV) infection during pregnancy. The objectives of this guideline are: TARGET POPULATION: Patients of child-bearing age, pregnant patients, and patients planning a pregnancy.

BENEFITS, HARMS, AND COSTS

The patient partners urged us to make awareness of preventive strategies a high priority, despite concern that discussing CMV with patients could cause unnecessary anxiety. CMV educational interventions have shown benefits from increased awareness of cCMV prevalence and preventive strategies among providers, patients, and families.

EVIDENCE

We searched MEDLINE, EMBASE, and CENTRAL databases for CMV in pregnancy. The search terms were developed using MeSH terms and keywords (Appendix). The results were filtered for articles published between January 2010 and October 2020 and systematic reviews, meta-analyses, clinical trials, and observational studies. The main inclusion criteria were pregnant patients and infants, as the target population, and CMV infection, as the diagnosis of interest. Recommendations are graded according to the U.S. Preventive Services Task Force grade of recommendations and level of certainty.

VALIDATION METHODS

We collaborated with patient partners, including members of CMV Canada (cmvcanada.com). In formulating our recommendations, we included patients' voices to add a unique and valuable perspective, thus ensuring that our recommendations are relevant to the patient-provider partnership.

INTENDED AUDIENCE

All perinatal health care providers. RECOMMENDATIONS (GRADE AND LEVEL OF CERTAINTY IN PARENTHESES).

Characteristics and serology of pregnant women with cytomegalovirus immunoglobulin G seroconversion during pregnancy in Japan

OBJECTIVE

Investigate the characteristics and serology of pregnant women with cytomegalovirus (CMV) immunoglobulin (Ig)G seroconversion during pregnancy to understand the risk factors associated with primary CMV infection and the occurrence of fetal congenital CMV infection.

MATERIALS AND METHODS

We retrospectively studied 3202 pregnant women who were CMV IgG-negative in early pregnancy and were retested for IgG in late pregnancy. Characteristics were compared between participants with and without IgG seroconversion, and serological parameters were compared between participants with and without fetal congenital CMV infection.

RESULTS

Twenty-six participants showed CMV IgG seroconversion and fifteen showed fetal congenital CMV infection. Seroconversion rates were significantly higher in teens (5.0%) than in older women (20s: 0.8%; 30s and over: 0.6%) (p < 0.001). Titers of CMV IgM at IgG seroconversion were higher in women without (median 8.66) than with (median 6.54) congenital infection (p = 0.045). The congenital infection rate was high when IgM titers at IgG seroconversion were low (47.1% with 4.00-12.00 titers and 100% with 1.21-3.99 IgM titers) (p = 0.048).

CONCLUSIONS

Nulliparous pregnant teenagers have a high risk of CMV IgG seroconversion and the CMV IgM titer at IgG seroconversion may help predict the occurrence of fetal congenital CMV infection.

Frequency, timing and risk factors for primary maternal cytomegalovirus infection during pregnancy in Quebec

INTRODUCTION

Maternal Cytomegalovirus (CMV) infection in the first trimester (T1) of pregnancy is a public health concern, as it increases the risk of severe neurodevelopmental outcomes associated with congenital infection compared to infections occurring later during pregnancy.

OBJECTIVES

To determine CMV seroprevalence in T1 of pregnancy, its trend, risk factors and the incidence rate of primary infection during pregnancy.

METHODS

Using the biobank of the prospective cohort "Grossesse en Santé de Québec" collected between April 2005 and March 2010 at the Québec-Laval Hospital, Québec, Canada, maternal CMV serology was determined using Abbott Architect Chemiluminescence microparticle immunoassays for immunoglobulin G(IgG), immunoglobulin M(IgM) titration and IgG avidity testing. Changepoint detection analysis was used to assess temporal trends. Risk factors associated with seropositivity were determined by multivariable logistic regression.

RESULTS

CMV seroprevalence in T1 of pregnancy was 23.4% (965/4111, 95% CI, 22.1-24.7%). The incidence rate for CMV primary infection during pregnancy was 1.8 (95% CI, 1.2-2.6) per 100 person-years. No changepoint was identified in the maternal CMV-seroprevalence trend. Multivariable analyses showed that T1 maternal CMV seropositivity was associated with having one child OR 1.3 (95% CI, 1.10-1.73) or two or more children OR 1.5 (95%CI, 1.1-2.1), ethnicity other than Caucasian OR 2.1 (95% CI, 1.1-3.8) and country of birth other than Canada and the USA OR 2.8 (95% CI, 1.5-4.9).

CONCLUSIONS

In this cohort, maternal seroprevalence in T1 of pregnancy and seroconversion rate were low. This information and identified risk factors could help guide the development and implementation of preventive actions and evidence-based health policies to prevent CMV infection during pregnancy.

Hypomanic symptoms in early pregnancy: prevalence and associated factors

Given that the perinatal period is a time of increased risk for pregnant women to manifest mental health problems, the identification of antenatal hypomanic symptoms is particularly important. However, data on antenatal hypomanic symptoms is lacking. The present study was aimed at filling this research gap by investigating the prevalence of hypomanic symptoms, including the "active-elated" and "irritable/risk-taking" sides of hypomanic symptoms at the first trimester, and examining their associations with anxiety and depressive symptoms at the following time points: the first trimester, the second trimester, and up to 6-week postpartum. A prospective longitudinal design with a quantitative approach was adopted. A consecutive sample of 229 pregnant Chinese women in Hong Kong was assessed. Hypomanic symptoms were assessed with the Hypomania Checklist-32 (HCL-32). Of the sample, 43.6% had elevated levels of hypomanic symptoms in the first trimester. Multiple regression analysis showed that after adjusting for potential confounding factors, irritable/risk-taking symptoms were independently associated with higher anxiety symptoms in the first and second trimesters and in the 6-week postpartum period. Primary healthcare practitioners should be made aware of antenatal hypomanic symptoms in pregnant women to facilitate early identification and intervention for anxiety and depression to improve the well-being of both mothers and infants.

Congenital cytomegalovirus infection: do pregnant women and healthcare providers know enough? A systematic review

BACKGROUND

Cytomegalovirus (CMV) is the most frequent cause of congenital infection worldwide causing serious morbidity in newborns, infants, and children. Despite the clinical importance of congenital CMV (cCMV), studies conducted so far conclude that there is limited awareness in both the medical community and public of cCMV infection. The aim of this systematic review was to assess the knowledge and awareness of cCMV among pregnant women and healthcare providers during the last decade.

METHODS

A literature search was performed in PubMed and Scopus, including studies published between 2011 and 2020. Eligibility criteria included articles focusing on either pregnant women or healthcare providers and reporting data about cCMV awareness. We included cross-sectional and interventional studies. Study quality was assessed using the Study Quality Assessment Tools by National Institute of Health.

RESULTS

Overall, 23 studies fulfilled the inclusion criteria, 13 studies referred to pregnant women and 10 to healthcare providers. A total of 6521 pregnant women and 3609 healthcare providers were included. The level of awareness of pregnant women about cCMV was low to moderate. However, pregnant women showed willingness to adopt hygiene strategies following interventional-educational practices. Concurrently, awareness among healthcare providers varied depending on the specialty. Nonetheless, a great proportion admitted feeling inadequate in advising pregnant women for cCMV screening and prevention.

CONCLUSION

The role of healthcare providers in growing awareness among pregnant women is of paramount importance. Due to the lack of an effective vaccine as yet, education of women regarding hygiene measures is currently the best strategy to prevent cCMV disease.

Cytomegalovirus (CMV) Shedding in French Day-Care Centers: A Nationwide Study of Epidemiology, Risk Factors, Centers' Practices, and Parents' Awareness of CMV

BACKGROUND

Congenital cytomegalovirus (CMV) remains an important healthcare burden, resulting from primary or secondary infection in pregnant women. Exposure to young children's saliva is a major risk factor, as prevalence of CMV shedding can reach 34%.

METHODS

This cross-sectional, multicenter, nationwide study was conducted in randomly selected day care centers (DCCs), and complemented with a survey among parents and DCCs. All children aged >3 months were eligible. The study measured the CMV shedding prevalence in children's saliva and described CMV genotypes epidemiology. The risk factors for CMV shedding and high viral load were evaluated using multivariable models.

RESULTS

A total of 93 DCCs participated. Among the 1770 enrolled children with evaluable samples, the CMV shedding prevalence was 40% (713/1770, 95% confidence interval, 34.6-46.1), independently associated with children aged between 12 and 18 months, history of CMV infection in ≥1 parents, a mid-level income. Prevalence increased with DCC staff workload and attending children number. Viral load was ≥5 log-copies CMV/mL in 48% (342/713). Risk factors for higher viral load included children aged between 12 and 18 months, and still being breastfed. The most frequent genotype combinations were gB1-gN4c-gH2 (6.9%), gB1-gN2-gH2 (6.3%), gB4a-gN3a-gH1 (6.3%), and gB1-gN3b-gH2 (5,7%). CMV awareness was low in parents: their serological status was unknown by 72% of mothers and 82% of fathers. Only 41% knew something about CMV.

CONCLUSIONS

CMV shedding was independently associated with risk factors related to the children, family and DCC. Some of these risk factors may influence prevention strategies, including through an improved information provided to parents.

CLINICAL TRIALS REGISTRATION

NCT01704222.

Using blood donors and solid organ transplant donors and recipients to estimate the seroprevalence of cytomegalovirus and Epstein-Barr virus in Canada: A cross-sectional study

BACKGROUND

Cytomegalovirus (CMV) and Epstein-Barr virus (EBV) infections are common, causing significant morbidity in pregnancy (congenital CMV) and transplant recipients (CMV, EBV). Canadian prevalence data are needed to model disease burden and develop strategies for future vaccines. We estimated prevalence using screening data from blood donors and solid organ transplant (SOT) donors and recipients.

METHODS

We retrospectively analyzed CMV and EBV serology from Alberta SOT donors (n = 3,016) and recipients (n = 4,614) (1984-2013) and Canadian Blood Services blood donors (n = 1,253,350) (2005-2014), studying associations with age, sex, organ, year, and geographic region.

RESULTS

CMV seroprevalence rises gradually with age. By age 70, CMV seropositivity ranged from 67% (blood donors) to 73% (SOT recipients). Significant proportions of women of child-bearing age were CMV-seronegative (organ donors, 44%; SOT recipients, 43%; blood donors, 61%). Blood donor CMV seroprevalence decreased from 48% in Western Canada to 30% in Eastern Canada. Women were more likely to be CMV-seropositive (ORs = 1.58, 1.45, and 1.11 for organ donors, SOT recipients, and blood donors, respectively) and EBV-seropositive (ORs = 1.87 and 1.46 for organ donors and SOT recipients, respectively). EBV prevalence rises rapidly, and by age 17-29 years, 81% of SOT recipients and 90% of organ donors were seropositive.

CONCLUSIONS

Canada has relatively low and perhaps decreasing age-specific EBV and CMV prevalence, making Canadians vulnerable to primary infection-associated morbidity and suggesting benefit from future vaccines. Collection and analysis of routine serology screening data are useful for observing trends.

Hygiene promotion might be better than serological screening to deal with Cytomegalovirus infection during pregnancy: a methodological appraisal and decision analysis

BACKGROUND

Cytomegalovirus infection is the most frequent viral congenital infection, with possible consequences such as deafness, or psychomotor retardation. In 2016, the French High Council of Public Health was mandated to update recommendations regarding prevention of cytomegalovirus infection in pregnant women. We summarize a critical appraisal of knowledge and deterministic decision analysis comparing the current no-screening situation to serological screening during pregnancy, and to hygiene promotion.

METHODS

Screening was defined as systematic serological testing, during the first trimester, with repeated tests as needed, to all pregnant women. Outcomes were: 1) severe sequela: intellectual deficiency with IQ ≤ 50 or hearing impairment < 70 dB or sight impairment (≤ 3/10 at best eye); 2) moderate sequela: any level of intellectual, hearing or sight deficiency; and 3) death or termination of pregnancy. We simulated the one-year course of cytomegalovirus infection in a cohort of 800,000 pregnant women. We developed a deterministic decision model, using best and min-max estimates, extracted from systematic reviews or original studies.

RESULTS

Relevant data were scarce or imprecise. We estimated that 4352 maternal primary infections would result in 1741 foetal infections, and an unknown number of maternal reinfections would result in 1699 foetal infections. There would be 788 cytomegalovirus-related consequences, including 316 foetal deaths or terminations of pregnancy, and 424 moderate and 48 severe sequelae. Screening would result in a 1.66-fold increase of poor outcomes, mostly related to a 2.93-fold increase in deaths and terminations of pregnancy, not compensated by the decrease in severe symptomatic newborns. The promotion of hygiene would result in a 0.75-fold decrease of poor outcomes, related to both a decrease in severe sequelae among symptomatic newborns (RR = 0.75; min-max: 1.00-0.68), and in deaths and terminations of pregnancy (RR = 0.75; min-max: 0.97-0.68).

CONCLUSIONS

Prevention of cytomegalovirus infection during pregnancy should promote hygiene; serological screening should not be recommended.

The MRI spectrum of congenital cytomegalovirus infection

Human cytomegalovirus (CMV) is an ubiquitous pathogen, with a high worldwide seroprevalence. When acquired in the prenatal period, congenital CMV (cCMV) is a major cause of neurodevelopmental sequelae and hearing loss. cCMV remains an underdiagnosed condition, with no systematic screening implemented in pregnancy or in the postnatal period. Therefore, imaging takes a prominent role in prenatal diagnosis of cCMV. With the prospect of new viable therapies, accurate and timely diagnosis becomes paramount, as well as identification of fetuses at risk for neurodevelopmental sequelae. Fetal magnetic resonance imaging (MRI) provides a complementary method to ultrasound (US) in fetal brain and body imaging. Anterior temporal lobe lesions are the most specific finding, and MRI is superior to US in their detection. Other findings such as ventriculomegaly, cortical malformations and calcifications, as well as hepatosplenomegaly, liver signal changes and abnormal effusions are unspecific. However, when seen in combination these should raise the suspicion of fetal infection, highlighting the need for a full fetal assessment. Still, some fetuses deemed normal on prenatal imaging are symptomatic at birth or develop delayed cCMV-associated symptoms, leaving room for improvement of diagnostic tools. Advanced MR sequences may help in this field and in determining prognosis, but further studies are needed.

Understanding pregnant women's readiness to engage in risk-reducing measures to prevent infections during pregnancy

The aim of this study was to develop a conceptual understanding of women's readiness to engage in behaviours to reduce the risk of acquiring infections during pregnancy, using cytomegalovirus, the most common congenital infection as a case. Thirty-three pregnant women participated in semi-structured interviews. The findings illustrate that for behavioural change to become viable, it is necessary for individuals to consider barriers or facilitators at the individual, inter-personal and system levels. By widening the theoretical lens beyond individual cognitive determinants, the model places sufficient emphasis on factors, such as collective identity, support networks, interaction with the healthcare system and wider community, relevant to pregnant women.

[A review on the prevention and treatment of congenital cytomegalovirus infection in mothers and infants]

Human cytomegalovirus (HCMV) has a high infection rate worldwide, and 85%-90% of congenital cytomegalovirus (CMV) infections are asymptomatic at birth, with the clinical manifestations of hearing loss, psychomotor retardation, and learning disabilities, while 10%-15% are symptomatic infections. Some preterm infants develop CMV infection after birth, which can cause sepsis-like syndrome, thrombocytopenia, neutropenia, liver injury, and lung injury. However at present, women of childbearing age have a lack of awareness of CMV. CMV education and hygiene precautions for pregnant women can prevent CMV infections in themselves and congenital CMV infections in their infants. No definite results have been obtained from the studies on the effect of CMV vaccine and high-titer immunoglobulin in preventing congenital CMV infection in fetuses. Recent studies have confirmed that the specificity and sensitivity of urinary or salivary CMV-DNA detection have reached more than 98%, which contributes to the early diagnosis of congenital CMV infection. In addition to short-term treatment with ganciclovir, long-term treatment with oral valganciclovir is safe for symptomatic congenital CMV infection and appears to have a better clinical effect than the short-term treatment. In the future, it is necessary to strengthen the health education for pregnant women, enhance the mother-to-child management of CMV infection, conduct the research on CMV vaccine, and further standardize treatment regimens.

Differential expression of miRNA in Carassius auratus gibelio in response to cyprinid herpesvirus 2 infection

miRNAs (microRNAs), a small endogenous non-coding RNAs, play crucial roles in post-transcriptional regulator of genes expression in various biological processes. Cyprinid Herpesvirus-2 (CyHV-2) is a highly pathogenic member of the alloherpesviridae that causes acute mass mortalities in populations of Carassius auratus gibelio and Carassius auratus auratus. However, the molecular mechanisms underlying the pathogenicity of CyHV-2 have not been fully determined. Here, miRNA expression profiles were identified via high-throughput sequencing in the kidney of Carassius auratus gibelio infected or uninfected with CyHV-2. The results showed that a total number of 840 known miRNAs and 48 putative novel miRNAs were identified. Then we compared the expression patterns of miRNAs in the two groups, 23 miRNAs were significantly differentially expressed between the uninfected and infected groups. Further, the expressions of 23 miRNAs were validated by quantitative reverse transcription polymerase chain reaction (qRT-PCR), the results showed that the expression patterns were basically the same with the sequencing. Prediction of targets of differentially expressed miRNAs revealed that the miRNAs participated in the regulation of multiple immune-related signaling pathways, including Chemokine signaling pathway, Apoptosis, Jak-STAT signaling pathway and MAPK signaling pathway. Taken together, these data provide insight into the regulatory mechanisms of miRNA and highlight the function of miRNA in the regulation of the immune response during the interaction between host and virus pathogens.

Maternal and fetal cytomegalovirus infection: diagnosis, management, and prevention

Congenital cytomegalovirus infection is a major cause of central nervous system and sensory impairments that affect cognition, motor function, hearing, language development, vestibular function, and vision. Although the importance of congenital cytomegalovirus infection is readily evident, the vast majority of maternal and fetal infections are not identified, even in developed countries. Multiple studies of prenatal cytomegalovirus infections have produced a body of knowledge that can inform the clinical approach to suspected or proven maternal and fetal infection. Reliable diagnosis of cytomegalovirus infection during pregnancy and accurate diagnosis of fetal infection are a reality. Approaches to preventing the transmission of cytomegalovirus from mother to fetus and to the treatment of fetal infection are being studied. There is evidence that public health approaches based on hygiene can dramatically reduce the rate of primary maternal cytomegalovirus infections during pregnancy. This review will consider the epidemiology of congenital cytomegalovirus infection, the diagnosis and management of primary infection during pregnancy, and approaches to preventing maternal infection.

Integrated analysis of mRNA and viral miRNAs in the kidney of Carassius auratus gibelio response to cyprinid herpesvirus 2

MicroRNAs (miRNAs) are small, non-coding single stranded RNAs that play crucial roles in numerous biological processes. Vertebrate herpesviruses encode multiple viral miRNAs that modulate host and viral genes. However, the roles of viral miRNAs in lower vertebrates have not been fully determined. Here, we used high-throughput sequencing to analyse the miRNA and mRNA expression profiles of Carassius auratus gibelio in response to infection by cyprinid herpesvirus 2 (CyHV-2). RNA sequencing obtained 26,664 assembled transcripts, including 2,912 differentially expressed genes. Based on small RNA sequencing and secondary structure predictions, we identified 17 CyHV-2 encoded miRNAs, among which 14 were validated by stem-loop quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) and eight were validated by northern blotting. Furthermore, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of miRNAs-mRNA pairs revealed diverse affected immune signalling pathways, including the RIG-I-like receptor and JAK-STAT pathways. Finally, we presented four genes involved in RIG-I-like pathways, including host gene IRF3, RBMX, PIN1, viral gene ORF4, which are negatively regulated by CyHV-2 encoded miRNA miR-C4. The present study is the first to provide a comprehensive overview of viral miRNA-mRNA co-regulation, which might have a key role in controlling post-transcriptomic regulation during CyHV-2 infection.

Nuclear domain 10 components upregulated via interferon during human cytomegalovirus infection potently regulate viral infection

Human cytomegalovirus (HCMV) is a ubiquitous betaherpesvirus that causes life-threatening disease in immunocompromised and immunonaïve individuals. Type I interferons (IFNs) are crucial molecules in the innate immune response to HCMV and are also known to upregulate several components of the interchromosomal multiprotein aggregates collectively referred to as nuclear domain 10 (ND10). In the context of herpesvirus infection, ND10 components are known to restrict gene expression. This raises the question as to whether key ND10 components (PML, Sp100 and hDaxx) act as anti-viral IFN-stimulated genes (ISGs) during HCMV infection. In this study, analysis of ND10 component transcription during HCMV infection demonstrated that PML and Sp100 were significantly upregulated whilst hDaxx expression remained unchanged. In cells engineered to block the production of, or response to, type I IFNs, upregulation of PML and Sp100 was not detected during HCMV infection. Furthermore, pre-treatment with an IFN-β neutralizing antibody inhibited upregulation of PML and Sp100 during both infection and treatment with HCMV-infected cell supernatant. The significance of ND10 components functioning as anti-viral ISGs during HCMV infection was determined through knockdown of PML, Sp100 and hDaxx. ND10 knockdown cells were significantly more permissive to HCMV infection, as previously described but, in contrast to control cells, could support HCMV plaque formation following IFN-β pre-treatment. This ability of HCMV to overcome the potently anti-viral effects of IFN-β in ND10 expression deficient cells provides evidence that ND10 component upregulation is a key mediator of the anti-viral activity of IFN-β.

Congenital cytomegalovirus infection in pregnancy and the neonate: consensus recommendations for prevention, diagnosis, and therapy

Congenital cytomegalovirus is the most frequent, yet under-recognised, infectious cause of newborn malformation in developed countries. Despite its clinical and public health importance, questions remain regarding the best diagnostic methods for identifying maternal and neonatal infection, and regarding optimal prevention and therapeutic strategies for infected mothers and neonates. The absence of guidelines impairs global efforts to decrease the effect of congenital cytomegalovirus. Data in the literature suggest that congenital cytomegalovirus infection remains a research priority, but data are yet to be translated into clinical practice. An informal International Congenital Cytomegalovirus Recommendations Group was convened in 2015 to address these questions and to provide recommendations for prevention, diagnosis, and treatment. On the basis of consensus discussions and a review of the literature, we do not support universal screening of mothers and the routine use of cytomegalovirus immunoglobulin for prophylaxis or treatment of infected mothers. However, treatment guidelines for infected neonates were recommended. Consideration must be given to universal neonatal screening for cytomegalovirus to facilitate early detection and intervention for sensorineural hearing loss and developmental delay, where appropriate. The group agreed that education and prevention strategies for mothers were beneficial, and that recommendations will need continual updating as further data become available.

Prevalence and Social Risk Factors for Hearing Impairment in Chinese Children-A National Survey

Hearing impairment may affect children’s communication skills, social development, and educational achievement. Little is known about the prevalence of hearing impairment among Chinese children. Data were taken from the 2006 second China National Survey on Disability (CNSD). Hearing impairment was defined as moderate (41–60 dB HL), severe (61–80 dB HL), profound (81–90 dB HL), or complete (>91 dB HL). Logistic regression was used to estimate the odds ratio (OR) and 95% confidence intervals (CI). A weighted number of 567,915 hearing impairment children were identified, yielding a prevalence of 17.49 per 10,000 people (95% CI: 16.90–18.08), with prevention or treatment options possible for 64.6% of hearing impairment children. The main causes of hearing impairment were hereditary, tympanitis, and drug intoxication. Illiteracy in one or both parents (mother: OR = 1.388, 95% CI: 1.125–1.714, p < 0.0001; father: OR = 1.537, 95% CI: 1.152–2.049, p < 0.0001 relative to no school or primary school), annual family income lower than national average (OR = 1.323, 95% CI: 1.044–1.675, p = 0.0203, relative to higher than national average), household size larger than three people (OR = 1.432, 95% CI: 1.164–1.762, p = 0.0007, relative to smaller than three people) and single-mother family (OR = 2.056, 95% CI: 1.390–3.042, p = 0.0176, relative to intact family) were the independence risk factors for hearing impairment among Chinese children. Lower annual family income, male children, larger household size, single-mother family, and lower levels of maternal and paternal education were independent risk factors for hearing impairment for Chinese children. Further studies on hearing impairment prevention and the relationship between parental social factors and the risk of hearing impairment are needed.