Impact of socioeconomic risk factors on the seroprevalence of cytomegalovirus infections in a cohort of pregnant Polish women between 2010 and 2011

Screening for TORCH Antibodies in Croatian Childbearing-Aged Women, 2014-2023

TORCH infections usually result in mild maternal morbidity, but may cause severe congenital abnormalities. Therefore, it is important to detect maternal infections, monitor the fetus after the disease has been recognized, and define the seronegative women who are at risk of primary infection during pregnancy. From 2014 to 2023, serum samples from 1032 childbearing-aged and pregnant women (16-45 years) were tested for IgM/IgG antibodies to the most common TORCH pathogens: Toxoplasma gondii, rubella virus (RUBV), cytomegalovirus (CMV), and herpes simplex viruses (HSV-1 and HSV-2). The overall IgG seroprevalence rates were 20.1% for T. gondii, 91.3% for RUBV, 70.5% for CMV, 66.8% for HSV-1, and 3.5% for HSV-2. Only HSV-2 seroprevalence was age-related, with a significant progressive increase in seropositivity from 0% in those aged less than 26 years to 9.3% in those older than 40 years. The seroprevalence of T. gondii was higher in residents of suburban/rural areas than in residents of urban areas (27.4% vs. 17.1%). In addition, participants from continental regions were more often toxoplasma-seropositive than those from coastal regions (22.2% vs. 15.3%). HSV-1 seroprevalence was also higher in suburban/rural areas (71.7% vs. 64.7%). Obstetric history was not associated with TORCH seropositivity. Univariate and multivariate risk analysis showed that suburban/rural areas of residence and continental geographic regions were significant risk factors for T. gondii seroprevalence. Furthermore, suburban/rural area of residence was a significant risk factor for HSV-1 seroprevalence, while older age was a significant risk factor for HSV-2 seroprevalence. A declining trend in the seroprevalence of all TORCH pathogens was observed compared to previous Croatian studies (2005-2011). Similarly, the proportion of women simultaneously IgG-seropositive to two or three pathogens decreased over time. The maternal serology before pregnancy could potentially reduce the burden of congenital TORCH infections.

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.

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.

Seroepidemiology study of Cytomegalovirus and Rubella in pregnant women in Luanda, Angola: geospatial distribution and its association with socio-demographic and clinical-obstetric determinants

BACKGROUND

Both CMV and Rubella virus infections are associated with the risk of vertical transmission, fetal death or congenital malformations. In Angola, there are no reports of CMV and Rubella studies. Therefore, our objectives were to study the seroprevalence of anti-CMV and anti-Rubella antibodies in pregnant women of Luanda (Angola), identify the risk of primary infection during pregnancy and evaluate the socio-demographic risk factors associated with both infections.

METHODS

A prospective cross-sectional study was conducted from August 2016 to May 2017. Specific anti-CMV and anti-Rubella antibodies were quantified by electrochemiluminescence and demographic and clinical data were collected using standardized questionnaire. Bivariate and multivariate logistic regression analysis were used to quantify the effect of clinical and obstetric risk factors on virus seroprevalence.

RESULTS

We recruited 396 pregnant women aged from 15 to 47. Among them, 335 (84.6%) were immune to both CMV and Rubella virus infections, while 8 (2.0%) had active CMV infection and 4 (1.0%) active RV infection but none had an active dual infection. Five women (1.2%) were susceptible to only CMV infection, 43 (10.9%) to only RV infection, and 1 (0.3) to both infections. Multivariate analysis showed a significant association between Rubella virus infection and number of previous births and suffering spontaneous abortion.

CONCLUSIONS

Overall, this study showed that there is a high prevalence of anti-CMV and anti-Rubella antibodies in pregnant women in Luanda. It also showed that a small but important proportion of pregnant women, about 11%, are at risk of primary infection with rubella during pregnancy. This emphasizes the need for vaccination.

Seroprevalence of Cytomegalovirus Antibodies by Electrochemiluminescence Method in Young Women Referred to the Clinical Laboratory, Sanandaj, Iran

Background and aims: Maternal primary and recurrent infection of cytomegalovirus (CMV) may be transmitted to the fetus during pregnancy and may have complications such as death or growth, along with the development retardation of the fetus and infant. The aim of this study was to determine the prevalence of immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies against CMV in young women, Sanandaj, Iran. Methods: To this end, 90 women (15-40 years old) referring to a clinical laboratory were randomly selected and announced their informed consent to participate in this cross-sectional study. Demographic information and women’s data were collected, including pregnancy, history of abortion, and history of blood transfusion. Then, women’s sera were measured for CMV IgG and IgM antibodies using the electrochemiluminescence technique. Finally, the data were analyzed by SPSS statistical software. Results: The prevalence of IgG and IgM antibodies against CMV in women was 92.2% (95% CI = 86.5-97.8) and 0%, respectively. In addition, the average CMV IgG antibody level was about 137.52 ± 85.215 SD IU/mL. The results revealed a significant statistical association between IgG antibody and pregnancy (P value = 0.012) while there was no association between CMV IgG antibody and other demographic data. Conclusions: In general, high percentages of women had CMV IgG antibody whereas 7.8% of them were susceptible. They are expected to acquire CMV primary infection, and therefore, the screening of antibodies to CMV is suggested for prenatal care.

Seroprevalence of human cytomegalovirus among pregnant women who had undergone abortion(s) attending El-Damazin Hospital for Obstetrics and Gynecology, Sudan: A cross-sectional study

Background: Human cytomegalovirus (HCMV) is a major cause of congenital infections. It is more widespread in developing countries and communities with low socioeconomic status. The infection can cause pregnancy loss or spontaneous abortion. Tests are available for the detection of HCMV IgG and IgM antibodies. Many pregnant women in Blue Nile State, Sudan, have suffered from recurrent pregnancy loss, and currently there is no available data concerning the prevalence of HCMV in Blue Nile state. This study aimed to determine HCMV antibodies (IgG and IgM) among pregnant women, who had undergone abortion(s), attending El-Damazin Hospital for Obstetrics and Gynecology.   Methods: This was a descriptive, cross-sectional hospital-based study. 270 pregnant women, who had undergone abortion(s) and who attended El-Damazin Hospital for Obstetrics and Gynecology, were included in the study from September to December 2018. Personal and clinical data were collected directly from each participant into a predesigned questionnaire. Serum samples were separated and stored at -20˚C until used. Samples were analyzed for HCMV IgG and IgM using enzyme-linked immune-sorbent assay (ELISA). Results: Participants were categorized into three age groups: 15-25 years (33.7%; 91/270); 26-40 years (62.2%; 168/270); and >41 years (4.1%; 11/270). The majority of the participants had IgG antibodies to HCMV (74.8%; 202/270), while only 13.3% (36/270) had IgM antibodies to HCMV. Most abortion cases were documented in the first trimester (85.6%; 231/270) and this had a significant relationship with IgG level (P=0.003). Low socioeconomic status was recorded in 84.8% (229/270) of participants and showed significant correlation with IgG level (P=0.025), whereas illiteracy was reported in 41.9% (113/270) of participants and did not have a significant relationship.   Conclusions: Seroprevalence of HCMV in this study population was 74.8% for IgG antibodies. There was an association between HCMV IgG level and first trimester abortion and low socioeconomic status among the studied women.

Seroprevalence of Rubella and Cytomegalia in Young Women from Biała Podlaska District

The aim of this study was to analyze the seroprevalence of rubella and cytomegalia among young women. The study included 175 healthy women from the Biała Podlaska District, aged 16 to 35 years. Anti-rubella and anti-CMV IgG were determined by ELISA. 172 (98.3%) study subjects tested positive for rubella antibodies, 1 (0.6%) was seroindeterminate and 2 (1.1%) were seronegative. CMV antibodies were detected in 119 (68.0%) participants; the series included also 1 (0.6%) seroindeterminate and 55 (31.4%) seronegative women. The levels of rubella and CMV antibodies were not significantly affected by age, place of residence and educational level of the study subjects.

Blood donor safety, prevalence and associated factors for cytomegalovirus infection among blood donors in Minna-Nigeria, 2014

Introduction

human cytomegalovirus (CMV) has remained a cause of morbidity and mortality in pregnancy and immunocompromised patients. CMV is transmissible through blood transfusion. We conducted a descriptive, cross-sectional study to assess blood donor safety and to determine the prevalence and associated factors for CMV infection among blood donors in Minna, Nigeria.

Methods

all consenting blood donors were screened for CMV antibodies (IgM and IgG) using ELISA kit and haematological indices using a haematological analyzer. We administered structured questionnaires to obtain socio-demographic and socio-economic data. Data were subjected to univariate, bivariate and multivariate statistical analyses using Epi Info version 3.5.4. Significant associations were presumed if p < 0.05.

Results

a total of 345 participantswere recruited, the majority were males 336 (97.4%). Monthly earnings of majority of the blood donors, 136 (40.6%) ranged from ₦18,000 to ₦35,000. The prevalence of CMV infection was 96.2%. The prevalence of anti-CMV IgG antibodies was 96.2% and that of IgM was 2.6%. Most of the study participants, 274 (79.4%) were family replacement donors. The majority of the blood donors 195 (56.5%) were anaemic (PCV < 36, Hb < 12g/dl). Those with positive CMV were more likely to be of high-income level (OR = 0.32, P = 0.04).

Conclusion

the seroprevalence of CMV was high with a significant proportion of donors capable of transmitting CMV infection to blood recipients. The majority of the blood donors were anaemic. High income level is associated with CMV infection. Quality of screening for anemia be improved.

The convergent epidemiology of tuberculosis and human cytomegalovirus infection

Although several factors are known to increase the risk of tuberculosis, the occurrence of tuberculosis disease in an infected individual is difficult to predict. We hypothesize that active human cytomegalovirus infection due to recent infection, reinfection or reactivation plays an epidemiologically relevant role in the aetiology of tuberculosis by precipitating the progression from latent tuberculosis infection to disease. The most compelling support for this hypothesis comes from the striking similarity in age-sex distribution between the two infections, important because the age-sex pattern of tuberculosis disease progression has not been convincingly explained. Cytomegalovirus infection and tuberculosis have other overlapping risk factors, including poor socio-economic status, solid organ transplantation and, possibly, sexual contact and whole blood transfusion. Although each of these overlaps could be explained by shared underlying risk factors, none of the epidemiological observations refute the hypothesis. If this interaction would play an epidemiologically important role, important opportunities would arise for novel approaches to controlling tuberculosis.

The convergent epidemiology of tuberculosis and human cytomegalovirus infection

Although several factors are known to increase the risk of tuberculosis, the occurrence of tuberculosis disease in an infected individual is difficult to predict. We hypothesize that active human cytomegalovirus infection due to recent infection, reinfection or reactivation plays an epidemiologically relevant role in the aetiology of tuberculosis by precipitating the progression from latent tuberculosis infection to disease. The most compelling support for this hypothesis comes from the striking similarity in age-sex distribution between the two infections, important because the age-sex pattern of tuberculosis disease progression has not been convincingly explained. Cytomegalovirus infection and tuberculosis have other overlapping risk factors, including poor socio-economic status, sexual contact, whole blood transfusion and solid organ transplantation. Although each of these overlaps could be explained by shared underlying risk factors, none of the epidemiological observations refute the hypothesis. If this interaction would play an epidemiologically important role, important opportunities would arise for novel approaches to controlling tuberculosis.

Seroepidemiology of Cytomegalovirus Infection in Pregnant Women in the Central Mexican City of Aguascalientes

Background

Infection with cytomegalovirus (CMV) during pregnancy may lead to congenital disease. Very little is known about the seroepidemiology of CMV infection in pregnant women in Mexico. We sought to determine the seroprevalence and correlates of CMV infection in pregnant women in Aguascalientes City, Mexico.

Methods

Through a cross-sectional study design, 289 pregnant women were examined for anti-CMV IgG and IgM antibodies in Aguascalientes City, Mexico. A standardized questionnaire was used to obtain the socio-demographic, clinical and behavioral characteristics of the pregnant women. The association between CMV infection and the characteristics of the pregnant women was assessed by bivariate and multivariate analyses.

Results

Anti-CMV IgG antibodies were detected in 259 (89.6%) of the 289 pregnant women studied. None of the 289 pregnant women were positive for anti-CMV IgM antibodies. Seroprevalence of CMV infection was significantly lower (P = 0.03) in pregnant women with reflex impairment (5/8: 62.5%) than in those without this clinical feature (246/272: 90.4%). Seroprevalence of CMV infection was significantly higher (P = 0.03) in pregnant women with 2 - 9 pregnancies (140/150: 93.3%) than in those with only one pregnancy (119/139: 86.2%). Logistic regression analysis of socio-demographic and behavioral variables showed that seropositivity to CMV was associated with contact with children (odds ratio (OR) = 3.56; 95% confidence interval (CI): 1.17 - 10.84; P = 0.02), whereas high (> 150 AU/mL) anti-CMV antibody levels were negatively associated with washing hands before eating (OR = 0.17; 95% CI: 0.05 - 0.63; P = 0.007).

Conclusions

We found a high endemicity of CMV infection in pregnant women in Aguascalientes City, Mexico. Factors associated with CMV infection found in this study may be useful for an optimal planning of preventive measures against CMV exposure in pregnant women.

Toll-like receptors genes polymorphisms and the occurrence of HCMV infection among pregnant women

Background

Human cytomegalovirus (HCMV) is the most common cause of intrauterine infections worldwide. The toll-like receptors (TLRs) have been reported as important factors in immune response against HCMV. Particularly, TLR2, TLR4 and TLR9 have been shown to be involved in antiviral immunity. Evaluation of the role of single nucleotide polymorphisms (SNPs), located within TLR2, TLR4 and TLR9 genes, in the development of human cytomegalovirus (HCMV) infection in pregnant women and their fetuses and neonates, was performed.

Methods

The study was performed for 131 pregnant women, including 66 patients infected with HCMV during pregnancy, and 65 age-matched control pregnant individuals. The patients were selected to the study, based on serological status of anti-HCMV IgG and IgM antibodies and on the presence of viral DNA in their body fluids. Genotypes in TLR2 2258 A > G, TLR4 896 G > A and 1196 C > T and TLR9 2848 G > A SNPs were determined by self-designed nested PCR-RFLP assays. Randomly selected PCR products, representative for distinct genotypes in TLR SNPs, were confirmed by sequencing. A relationship between the genotypes, alleles, haplotypes and multiple variants in the studied polymorphisms, and the occurrence of HCMV infection in pregnant women and their offsprings, was determined, using a logistic regression model.

Results

Genotypes in all the analyzed polymorphisms preserved the Hardy-Weinberg equilibrium in pregnant women, both infected and uninfected with HCMV (P > 0.050). GG homozygotic and GA heterozygotic status in TLR9 2848 G > A SNP decreased significantly the occurrence of HCMV infection (OR 0.44 95% CI 0.21–0.94 in the dominant model, P ≤ 0.050). The G allele in TLR9 SNP was significantly more frequent among the uninfected pregnant women than among the infected ones (χ² = 4.14, P ≤ 0.050). Considering other polymorphisms, similar frequencies of distinct genotypes, haplotypes and multiple-SNP variants were observed between the studied groups of patients.

Conclusions

TLR9 2848 G > A SNP may be associated with HCMV infection in pregnant women.

Electronic supplementary material

The online version of this article (doi:10.1186/s12985-017-0730-8) contains supplementary material, which is available to authorized users.

The role of single nucleotide polymorphisms, contained in proinflammatory cytokine genes, in the development of congenital infection with human cytomegalovirus in fetuses and neonates

PURPOSE

The research project targeted the distribution of genotypes, alleles and haplotypes in single nucleotide polymorphisms (SNPs) within the interleukin (IL) 1A, IL1B, IL6, IL12B and TNFA genes, in fetuses and neonates, congenitally infected with human cytomegalovirus (HCMV), and among uninfected controls.

METHODS

The study included 20 fetuses and neonates with congenital HCMV infection and 31 control individuals. The genotypes in SNPs of the studied cytokine genes were identified by a self-designed nested PCR-RFLP assays. Selected genotypes, representing distinct variants in analyzed polymorphisms, were confirmed by sequencing. The relationship between the genetic status of the studied polymorphisms and congenital infection development was estimated, using a logistic regression model.

RESULTS

The CT haplotype, composed of C allele determined in IL1A -889 C > T and T allele in IL1B +3954 C > T SNP, increased the risk of congenital HCMV infection, as well as the onset of disease related symptoms (P ≤ 0.0001). Considering disease outcome, the risk of development of symptoms, was increased among the CT heterozygotes in IL1A -889 C > T polymorphism (OR 2.86, 95% CI 0.24-33.90; P = 0.045). Moreover, multiple-SNP variants CCGAG in the range of all the SNPs, analyzed in the study, increased the risk of congenital infection with HCMV (OR 7.94, 95% CI 1.38-45.69; P = 0.026).

CONCLUSIONS

Polymorphisms within the proinflammatory cytokine genes may contribute to the development of congenital infection with HCMV.

Association of SNPs from IL1A, IL1B, and IL6 Genes with Human Cytomegalovirus Infection Among Pregnant Women

The study was aimed to estimate the role and prevalence rates of genotypes, haplotypes, and alleles, located within the single-nucleotide polymorphisms (SNPs) of interleukin (IL) 1A, IL1B, and IL6 genes, in the occurrence and development of human cytomegalovirus (HCMV) infection among pregnant women. A research was conducted in 129 pregnant women, out of whom, 65 were HCMV infected and 64 were age-matched control uninfected individuals. HCMV DNA was quantitated for UL55 gene by the real-time Q PCR in the body fluids. The genotypic statuses within the SNPs were determined by nested PCR-RFLP assays and confirmed, by sequencing for randomly selected representative PCR products. A relationship between the genotypes and alleles, as well as haplotypes and multiple variants in the studied polymorphisms, and the occurrence of HCMV infection in pregnant women, was determined using a logistic regression model. TT genotype within IL1A polymorphism significantly decreased the risk of HCMV infection (OR 0.32, 95% CI 0.09-1.05; p ≤ 0.050). Considering IL6 SNP, the prevalence rate of GC genotype was significantly decreased among the HCMV infected, compared to the uninfected control individuals (OR 0.45, 95% CI 0.21-0.99; p ≤ 0.050). Moreover, CC homozygotic status in IL6 SNP, found in pregnant women, significantly decreased the risk of congenital infection with HCMV in their offsprings (OR 0.12; p ≤ 0.050). In multiple SNP analysis, TC haplotype within the IL1 polymorphisms significantly decreased the risk of the infection in pregnant women (OR 0.38 95% CI 0.15-0.96; p ≤ 0.050). In addition, TTG complex variants for all the studied polymorphisms and TG variants for IL1B and IL6 SNPs were significantly more prevalent among the infected offsprings with symptomatic congenital cytomegaly than among the asymptomatic cases (p ≤ 0.050). In conclusion, the analyzed IL1A -889 C>T, IL1B +3954 C>T, and IL6 -174 G>C polymorphisms may be associated with the occurrence and development of HCMV infection among studied patients.

Seroepidemiology of cytomegalovirus infections in Croatia

BACKGROUND

Cytomegalovirus (CMV) is endemic worldwide, with marked differences in the seroprevalence rates between countries. The aim of this study was to analyze the seroprevalence of CMV infections in Croatia.

METHODS

During a 3-year period (2013-2015) 2438 consecutive serum samples collected from Croatian residents were tested for the presence of CMV IgM and IgG antibodies using enzyme-linked immunoassay. The IgM/IgG positive samples were further tested for IgG avidity.

RESULTS

The overall seroprevalence rates for CMV IgG and IgM antibodies were 74.4 % and 4.3 %, respectively. The IgG seroprevalence showed significant differences between population groups: children/adolescents 54.6 %, general adult population 77.2 %, hemodialysis patients 91.4 % (p < 0.001). Seropositivity of CMV was strongly age-dependent with prevalences ranging from 53.0 % in children less than 10 years old to 93.8 % in persons above 60 years (p < 0.001). There was no difference in the prevalence rate between women with normal pregnancy and women with poor obstetric history. Gender and place of residence were not associated with CMV seropositivity. Using IgG avidity, current/recent primary CMV infection was confirmed by a low/borderline avidity index (AI) in 46.7 % participants, while in 53.3 % a high AI indicated CMV reactivation or reinfection. Primary infections were detected mainly in children and adolescents (83.2 % and 70.5 %, respectively), while reactivation/reinfection was common in persons older than 40 (77.0-100 %). Reactivation/reinfection was most commonly detected in hemodialysis patients (92.3 %). Logistic regression showed that older age and being on hemodialysis were significant predictors of CMV seropositivity.

CONCLUSION

Infections with CMV are widespread in the Croatian population. Older age and being on hemodialysis appear to be the main risk factors for CMV infection.

Are female daycare workers at greater risk of cytomegalovirus infection? A secondary data analysis of CMV seroprevalence between 2010 and 2013 in Hamburg, Germany

Background: Close contact with asymptomatic children younger than three years is a risk factor for a primary cytomegalovirus (CMV) infection. In pregnant women, such primary infection increases the risk of CMV-induced feto- or embryopathy. Daycare providers have therefore implemented working restrictions for pregnant daycare workers (DCWs) in accordance with legislation and guidelines for maternity protection. However, little is known about the infection risk for DCWs. We therefore compared the prevalence of CMV antibodies of pregnant DCWs to that of female blood donors (BDs).

Method: In a secondary data analysis, the prevalence of anti-CMV IgG among pregnant DCWs (N=509) in daycare centers (DCCs) was compared to the prevalence of female first-time BDs (N=14,358) from the greater region of Hamburg, Germany. Data collection took place between 2010 and 2013. The influence of other risk factors such as age, pregnancies and place of residence was evaluated using logistic regression models.

Results: The prevalence of CMV antibodies in pregnant DCWs was higher than in female BDs (54.6 vs 41.5%; OR 1.6; 95%CI 1.3–1.9). The subgroup of BDs who had given birth to at least one child and who lived in the city of Hamburg (N=2,591) had a prevalence of CMV antibodies similar to the prevalence in pregnant DCWs (53.9 vs 54.6%; OR 0.9; 95%CI 0.8–1.2). Age, pregnancy history and living in the center of Hamburg were risk factors for CMV infections.

Conclusion: The comparison of pregnant DCWs to the best-matching subgroup of female first-time BDs with past pregnancies and living in the city of Hamburg does not indicate an elevated risk of CMV infection among DCWs. However, as two secondary data sets from convenience samples were used, a more detailed investigation of the risk factors other than place of residence, age and maternity was not possible. Therefore, the CMV infection risk in DCWs should be further studied by taking into consideration the potential preventive effect of hygiene measures.

TLR9 2848 GA heterozygotic status possibly predisposes fetuses and newborns to congenital infection with human cytomegalovirus

Background

Some single nucleotide polymorphisms (SNP), located in Toll-like receptor (TLR) genes, were reported to be associated with human cytomegalovirus (HCMV) infections. The study was aimed to assess the correlation of SNPs at TLR4 and TLR9 genes with the occurrence of congenital cytomegaly, based on available samples.

Methods

Reported case-control study included both HCMV infected and non-infected fetuses and newborns. The specimens were classified to the molecular analyses, based on serological features of the recent infection and HCMV DNAemia in body fluids. TLR SNPs were studied, using multiplex nested PCR-RFLP assay, and determined genotypes were confirmed by sequencing. Hardy-Weinberg equilibrium was assessed for the identified genotypes. The linkage disequilibrium was also estimated for TLR4 SNPs. A relationship between the status of TLR genotypes and congenital cytomegaly development was estimated, using a logistic regression model.

Results

Hardy Weinberg equilibrium was observed for almost all SNPs, both infected and non-infected patients, with exception of TLR4 896 A>G polymorphism in the control group (P≤0.050). TLR4 896 A>G and 1196 C>T SNPs were found in linkage disequilibrium in both study groups (P≤0.050). The CC genotype at TLR4 1196 SNP and the GA variant at TLR9 2848 G>A SNP were significantly associated with HCMV infection (P≤0.050). The risk of congenital cytomegaly was higher in heterozygotes at TLR9 SNP than in the carriers of other genotypic variants at the reported locus (OR 4.81; P≤0.050). The GC haplotype at TLR4 SNPs and GCA variants at TLR4 and TLR9 SNPs were significantly associated with HCMV infection (P≤0.0001). The ACA variants were more frequent among fetuses and neonates with symptomatic, rather than asymptomatic cytomegaly (P≤0.0001).

Conclusions

TLR4 and TLR9 polymorphisms may contribute to the development of congenital infection with HCMV in fetuses and neonates. The TLR9 2848 GA heterozygotic status possibly predisposes to HCMV infection, increasing the risk of congenital cytomegaly development.