Mission, Organization, and Future Direction of the Serological Sciences Network for COVID-19 (SeroNet) Epidemiologic Cohort Studies.

Background: Global efforts are needed to elucidate the epidemiology of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the underlying cause of coronavirus disease 2019 (COVID-19), including seroprevalence, risk factors, and long-term sequelae, as well as immune responses after vaccination across populations and the social dimensions of prevention and treatment strategies. Methods: In the United States, the National Cancer Institute in partnership with the National Institute of Allergy and Infectious Diseases, established the SARS-CoV-2 Serological Sciences Network (SeroNet) as the nation's largest coordinated effort to study coronavirus disease 2019. The network comprises multidisciplinary researchers bridging gaps and fostering collaborations among immunologists, epidemiologists, virologists, clinicians and clinical laboratories, social and behavioral scientists, policymakers, data scientists, and community members. In total, 49 institutions form the SeroNet consortium to study individuals with cancer, autoimmune disease, inflammatory bowel diseases, cardiovascular diseases, human immunodeficiency virus, transplant recipients, as well as otherwise healthy pregnant women, children, college students, and high-risk occupational workers (including healthcare workers and first responders). Results: Several studies focus on underrepresented populations, including ethnic minorities and rural communities. To support integrative data analyses across SeroNet studies, efforts are underway to define common data elements for standardized serology measurements, cellular and molecular assays, self-reported data, treatment, and clinical outcomes. Conclusions: In this paper, we discuss the overarching framework for SeroNet epidemiology studies, critical research questions under investigation, and data accessibility for the worldwide scientific community. Lessons learned will help inform preparedness and responsiveness to future emerging diseases.

Virological Characteristics of Hospitalized Children With SARS-CoV-2 Infection.

BACKGROUND AND OBJECTIVES: In children with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, virological characteristics and correlation with disease severity have not been extensively studied. The primary objective in this study is to determine the correlation between SARS-CoV-2 viral load (VL) in infected children with age, disease severity, and underlying comorbidities. METHODS: Children <21 years, screened for SARS-CoV-2 at the time of hospitalization, who tested positive by polymerase chain reaction were included in this study. VL at different sites was determined and compared between groups. RESULTS: Of the 102 children included in this study, 44% of the cohort had asymptomatic infection, and children with >1 comorbidity were the most at risk for severe disease. VL in children with symptomatic infection was significantly higher than in children with asymptomatic infection (3.0 × 105 vs 7.2 × 103 copies per mL; P = .001). VL in the respiratory tract was significantly higher in children <1 year, compared with older children (3.3 × 107 vs 1.3 × 104 copies per mL respectively; P < .0001), despite most infants presenting with milder illness. Besides the respiratory tract, SARS-CoV-2 RNA was also detectable in samples from the gastrointestinal tract (saliva and rectum) and blood. In 13 children for whom data on duration of polymerase chain reaction positivity was available, 12 of 13 tested positive 2 weeks after initial diagnosis, and 6 of 13 continued to test positive 4 weeks after initial diagnosis. CONCLUSIONS: In hospitalized children with SARS-CoV-2, those with >1 comorbid condition experienced severe disease. SARS-CoV-2 VL in the respiratory tract is significantly higher in children with symptomatic disease and children <1 year of age.

Comparing Nasopharyngeal and Midturbinate Nasal Swab Testing for the Identification of Severe Acute Respiratory Syndrome Coronavirus 2.

Testing of paired midturbinate (MT) nasal and nasopharyngeal (NP) swabs, collected by trained personnel from 40 patients with coronavirus disease 2019 (COVID-19), showed that more NP (76/95 [80%]) than MT swabs tested positive (61/95 [64%]) (P = .02). Among samples collected a week after study enrollment, fewer MT than NP samples were positive (45% vs 76%; P = .001).

Viral shedding, and distribution of cytomegalovirus glycoprotein H (UL75), glycoprotein B (UL55), and glycoprotein N (UL73) genotypes in congenital cytomegalovirus infection.

BACKGROUND: Children with congenital CMV infection (cCMV) shed virus in urine and saliva for prolonged periods of time. Outcome of cCMV varies from asymptomatic infection with no sequelae in most cases, to severe longterm morbidity. The factors associated with asymptomatic cCMV are not well defined. We evaluated the viral shedding in a cohort of infants with cCMV identified on newborn screening. In addition, we describe the distribution of viral genotypes in our cohort of asymptomatic infants and previous cohorts of cCMV children in the literature. METHODS: Study population consisted of 40 children with cCMV identified in screening of 19,868 infants, a prevalence of 2/1000. The viral shedding was evaluated at 3 and 18 months of age by real-time CMV-PCR of saliva and plasma, and CMV culture of urine. CMV positive saliva samples were analyzed for genotypes for CMV envelope glycoproteins gB (UL55), and gH (UL75) by genotype specific real-time PCR, and gN (UL73) by cloning and sequencing RESULTS: At 3 months age 40/40 saliva and urine samples, and 19/40 plasma samples were positive for CMV. At 18 months age all urine samples tested (33/33), 9/37 of saliva samples, and 2/34 plasma samples were positive for CMV. The genotype distribution did not differ from the published data CONCLUSIONS: The urinary virus shedding is more persistent than salivary shedding in children with cCMV. The genotype distribution was similar to previous literature and does not explain the low disease burden of cCMV in our population.

Cytomegalovirus Seroprevalence and Birth Prevalence of Congenital CMV Infection in Bosnia and Herzegovina: A Single-Center Experience.

BACKGROUND: Congenital cytomegalovirus infection (cCMV) is a leading cause of sensorineural hearing loss (SNHL) and neurodevelopmental disabilities in developed countries. Although high cCMV rates have been reported in populations with high seroprevalence, the cCMV prevalence in low/middle-income countries in Europe has not been defined. OBJECTIVE: To determine cytomegalovirus (CMV) seroprevalence and the cCMV prevalence in Bosnia and Herzegovina. METHODS: Between March 2010 and February 2019, 5222 sera samples from patients seen at the University Clinical Hospital Mostar were tested for CMV IgG. The cord blood samples collected from 2091 infants between July 2011 and January 2013 were analyzed for CMV IgG and CMV DNA. The cCMV prevalence was determined by testing saliva swabs from 1293 infants between November 2015 and October 2016. RESULTS: The overall CMV IgG prevalence was 81.4% (95% confidence interval: 0.8-0.82). Significantly higher prevalence was observed among females (84.9%) than in males (77.0%), and the rate increased from 50.8% in the 1 to 5 years group to 97.7% in the group > 65 years old. Most cord blood samples (2091/1925, 92.1%) were CMV IgG positive, and 2 (0.1%) were CMV DNA positive. Of the 1293 saliva swabs, 8 (0.62%; 95% confidence interval: 0.3-1.2) were CMV positive. All 8 infected infants had asymptomatic cCMV, and none had SNHL at 18 months of age. CONCLUSIONS: In a highly CMV seropositive population, the prevalence of cCMV was lower compared with that reported from other low/middle-income countries populations. None of the infected infants had symptomatic infection or SNHL at 18 months.

The Burden of Congenital Cytomegalovirus Infection: A Prospective Cohort Study of 20 000 Infants in Finland.

BACKGROUND: Congenital cytomegalovirus (cCMV) infection is the most common congenital infection and causes significant morbidity. This study was undertaken to evaluate the benefits of screening newborns for cCMV and to understand the cCMV disease burden in Finland. METHODS: Infants born in Helsinki area hospitals were screened for CMV by testing their saliva with a real-time polymerase chain reaction assay. The CMV-positive infants and matched controls were monitored to determine their neurodevelopmental, audiological, and ophthalmological outcomes at 18 months of age. Griffiths Mental Development Scales, otoacoustic emission and sound field audiometry, and ophthalmologic examination were performed. RESULTS: Of the 19868 infants screened, 40 had confirmed cCMV infection (prevalence, 2 in 1000 [95% confidence interval, 1.4-2.6 in 1000]). Four (10%) infants had symptomatic cCMV. Griffiths general quotients did not differ significantly between the CMV-positive (mean, 101.0) and control (mean, 101.6) infants (P = .557), nor did quotients for any of the Griffiths subscales (locomotion, personal-social, hearing and language, eye and hand, performance) (P = .173-.721). Four of 54 CMV-positive ears and 6 of 80 CMV-negative ears failed otoacoustic emission testing (P = 1.000). The mean minimal response levels over the frequencies 500 Hz to 4 kHz in the sound field audiometry did not differ between CMV-positive (mean, 34.31-dB hearing level) and control (mean, 32.73-dB hearing level) infants (P = .338). No CMV-related ophthalmologic findings were observed. CONCLUSIONS: The prevalence of cCMV was low, and outcomes at 18 months of age did not differ between the infected infants and healthy control infants. With such a low burden in Finland, universal newborn screening for cCMV seems unwarranted.

Nonprimary Maternal Cytomegalovirus Infection After Viral Shedding in Infants.

BACKGROUND: Most infants with congenital Cytomegalovirus (CMV) infection are born to seropositive women as a result of maternal CMV nonprimary infection (reinfection or reactivation). Although infected children are known to transmit CMV to their seronegative mothers, the frequency and magnitude of nonprimary maternal CMV infection after exposure to viral shedding by children in their household have not been characterized. METHODS: A cohort of Ugandan newborns and their mothers were tested weekly for CMV by quantitative polymerase chain reaction of oral swabs. Infant primary infection and maternal nonprimary infection were defined by the onset of persistent high-level oral CMV shedding. Strain-specific antibody testing was used to assess maternal reinfection. Cox regression models with time-dependent covariates were used to evaluate risk factors for nonprimary maternal infection. RESULTS: Nonprimary CMV infection occurred in 15 of 30 mothers, all after primary infection of their infants by a median of 6 weeks (range: 1-10) in contrast to none of the mothers of uninfected infants. The median duration of maternal oral shedding lasted 18 weeks (range: 4-42) reaching a median maximum viral load of 4.69 log copies/mL (range: 3.22-5.64). Previous-week infant CMV oral quantities strongly predicted maternal nonprimary infection (hazard ratio: 2.32 per log10 DNA copies/swab increase; 95% confidence interval: 1.63-3.31). Maternal nonprimary infections were not associated with changes in strain-specific antibody responses. CONCLUSIONS: Nonprimary CMV infection was common in mothers after primary infection in their infants, consistent with infant-to-mother transmission. Because infants frequently acquire CMV from their mothers, for example, through breast milk, this suggests the possibility of "ping-pong" infections. Additional research is needed to characterize the antigenic and genotypic strains transmitted among children and their mothers.

Breast Milk Human Cytomegalovirus (CMV) Viral Load and the Establishment of Breast Milk CMV-pp65-Specific CD8 T Cells in Human CMV Infected Mothers.

The role of human cytomegalovirus (HCMV)-specific T-cell responses in breast milk of HCMV-seropositive mothers is not well defined. In these studies, we demonstrate that the frequency of cytomegalovirus (CMV)-pp65-specific T-cell responses in peripheral blood mononuclear cells (PBMCs) and breast milk cells (BMCs) is increased for CD8+ T cells in both sample sources when compared with CD4+ T cells. The frequency of pp55-specific CD8 T cells producing interferon γ (IFN-γ) alone or dual IFN-γ/granzyme rB producers is increased in breast milk compared with PBMCs. Lastly, we observed a positive correlation between breast milk viral load and the CD8 pp65-specific response, suggesting that local virus replication drives antigen-specific CD8 T cells into the breast.

Genotypic diversity and mixed infection in newborn disease and hearing loss in congenital cytomegalovirus infection.

BACKGROUND: Congenital cytomegalovirus (cCMV) is a common congenital infection and a leading nongenetic cause of sensorineural hearing loss (SNHL). CMV exhibits extensive genetic variability, and infection with multiple CMV strains (mixed infection) was shown to be common in congenital CMV. The role of mixed infections in disease and outcome remains to be defined. METHODS: Genotyping of envelope glycoproteins, UL55 (gB), UL73 (gN) and UL75 (gH), was performed on saliva specimens of 79 infants from the ongoing CMV and Hearing Multicenter Screening (CHIMES) Study and on blood and urine specimens of 52 infants who participated in natural history studies at the University of Alabama at Birmingham. Genotyping of UL144 and US28 was also performed in the CHIMES cohort. The association of individual genotypes and mixed infection with clinical findings at birth and SNHL was examined. RESULTS: Thirty-seven of 131 infants (28%) were symptomatic at birth and 26 (20%) had SNHL at birth. All known genotypes of UL55, UL75, UL73 and US28 were represented, and no particular genotype was associated with symptomatic infection or SNHL. UL144 subtype C was more common in symptomatic infants but not associated with SNHL. Mixed infection was observed in 59 infants (45%) and not associated with symptoms (P = 0.43) or SNHL at birth (P = 0.82). In the cohort of 52 infants with long-term hearing outcome, mixed infection at birth was not predictive of SNHL. CONCLUSIONS: Mixed infection is common in infants with congenital CMV but is neither associated with symptomatic infection nor associated with SNHL.

Strain-specific neutralizing antibody responses against human cytomegalovirus envelope glycoprotein N.

The human cytomegalovirus (HCMV) gM-gN complex is a major target of virus-neutralizing activity, and gN subtypes induce strain-specific antibodies. However, the biological significance of HCMV gN polymorphisms is not known. Neutralizing antibody responses against HCMV gN recombinant viruses were investigated at study entry in 80 healthy HCMV-seropositive women who were monitored for the appearance of new antibody specificities against linear strain-specific epitopes on glycoproteins gH and gB as evidence of HCMV reinfection. Neutralizing activity against all four gN recombinant viruses was seen in 74% of subjects, and 61% of subjects had strain-specific responses. Significantly fewer women (9/39 subjects [23%]) with serological evidence of reinfection had strain-specific neutralizing responses than the women without reinfection (21/41 subjects [51%]). Women with antibodies against at least one of the four linear gB and gH antigens at study entry had higher neutralizing titers against gN-1 (P = 0.006) and gN-2 (P = 0.007). Neutralizing titers of ≥400 against gN-3 (P = 0.043) and gN-4 (P = 0.049) at study entry were associated with longer times to serological evidence of reinfection. The findings demonstrate that HCMV gN elicits strain-specific neutralizing antibody responses and that broader anti-gN neutralizing activity may provide some protection from reinfection with a different virus strain.

Mixed infection and strain diversity in congenital cytomegalovirus infection.

BACKGROUND: Cytomegalovirus (CMV), the most common cause of congenital infection, exhibits extensive genetic variability. We sought to determine whether multiple CMV strains can be transmitted to the fetus and to describe the distribution of genotypes in the saliva, urine, and blood. METHODS: Study subjects consisted of a convenience sampling of 28 infants found to be CMV-positive on newborn screening as part of an ongoing study. Genotyping was performed on saliva specimens obtained during newborn screening and urine, saliva, and blood obtained at a later time point within the first 3 weeks of life. RESULTS: Six (21.4%) of the 28 saliva samples obtained within the first 2 days of life contained >1 CMV genotype. Multiple CMV genotypes were found in 39% (5/13) of urine, saliva, and blood samples obtained within the first 3 weeks of life from 13 of the 28 newborns. There was no predominance of a CMV genotype at a specific site; however, 4 infants demonstrated distinct CMV strains in different compartments. CONCLUSIONS: Infection with multiple CMV strains occurs in infants with congenital CMV infection. The impact of intrauterine infection with multiple virus strains on the pathogenesis and long-term outcome remains to be elucidated.

Diagnostic consequences of cytomegalovirus glycoprotein B polymorphisms.

Failure of a cytomegalovirus (CMV) real-time PCR assay targeting glycoprotein B (gB) was investigated. A multiplex assay targeting gB and immediate-early 2 (IE2) genes showed discordant results (gB negative and IE positive or a >10-fold-higher viral load with IE primers) in saliva from 14.6% of CMV-infected newborns. Sequencing revealed 3 patterns of gB variations.

Enzyme-linked immunosorbent assay method for detection of cytomegalovirus strain-specific antibody responses.

Reliable methods for the detection of cytomegalovirus (CMV) strain-specific serological responses are lacking. We describe a simple and reliable enzyme-linked immunosorbent assay method developed to detect antibodies against the polymorphic epitopes within the two envelope glycoproteins of CMV, glycoproteins H and B. This assay is useful for the detection of serologic responses to CMV strains and the identification of CMV reinfections.

High frequency of parasitic and viral stool pathogens in patients with active ulcerative colitis: report from a tropical country.

OBJECTIVE: Diarrhoeal relapses in patients with ulcerative colitis (UC) may be associated with enteric infections and its diagnosis may lessen avoidable exposure to corticosteroids and/or immunosuppressants. The purpose of this study was to assess the frequency of stool pathogens (parasitic and viral) in patients with active UC. MATERIAL AND METHODS: This prospective cross-sectional study included 49 consecutive patients (32 M, 17 F, mean age 35.8+/-12 years) with active UC. Three stool samples were collected from each patient and examined for parasitic infection. Rectal biopsies were obtained during sigmoidoscopy to demonstrate cytomegalovirus (CMV) inclusion bodies and to conduct qualitative polymerase chain reaction (PCR) for CMV and herpes simplex virus (HSV) DNA detection. RESULTS: Median duration of illness was 3.9+/-3.7 years and 83.7% of the patients had moderate to severe disease. The prevalence of parasitic infections in UC was 12%. The organisms isolated were Strongyloides stercoralis in 4%, Ankylostoma duodenale in 4%, Cryptosporidium in 2% and Entamoeba histolytica in 2% of the patients. The prevalence of CMV and HSV in rectal biopsies using qualitative PCR was 8% and 10%, respectively. No predictive factor was identified with CMV superinfection in patients with active UC. CONCLUSIONS: In India there is a high prevalence of parasitic and viral infections in patients with active UC. The results of the study suggest that, in tropical countries with a known high prevalence of parasitic diseases, aggressive evaluation for parasitic and viral infections should be carried out, as early identification and prompt treatment of such infections can improve the clinical course of patients with active UC.

Congenital cytomegalovirus infection in a highly seropositive semi-urban population in India.

To determine the incidence and natural history of congenital cytomegalovirus (CMV) infection in a population of women with near universal serologic reactivity for CMV, a prospective study of 423 women attending the antenatal clinic of the Comprehensive Rural Health Center in northern India was conducted. All 9 (2.1%) CMV positive infants were born to mothers who were CMV seropositive at the first antenatal visit. One child had hepatosplenomegaly at birth and another child had mild unilateral hearing loss at 4 months of age.

Human papillomavirus-type distribution in women with and without cervical neoplasia in north India.

Our objective was to determine the human papillomavirus (HPV)-type prevalence in cervical samples in women with and without cervical neoplasia in an opportunistic hospital-based cancer-screening program. A cross-sectional study of 524 women presenting from January 2003 through June 2005 with symptoms of persistent vaginal discharge, intermenstrual bleeding, and postcoital bleeding or detected to have an unhealthy cervix underwent HPV genotyping by consensus polymerase chain reaction and reverse line-blot hybridization assay, conventional Pap smear, and colposcopy, with directed biopsy from all lesions detected. The prevalence rates of HPV infection among women with normal, low-grade cervical neoplasia (CIN 1) and high-grade CIN (>CIN2) were found to be 7.6%, 42.3%, and 87.5%, respectively. Seventeen high-risk and 6 low-risk HPV types were identified by the reverse line-blot assay. Multiple infections were seen in 20% of women. In normal women, the 6 commonest types were HPV-16, HPV-89, HPV-39, HPV-52, HPV-62, and HPV-18, whereas in high-grade disease, these were all high-risk types HPV-16, HPV-18, HPV-33, HPV-39, HPV-35, and HPV-56. HPV-16 was the commonest type in all groups, seen in 49.4% cases overall and in 74.3% of high-grade squamous intraepithelial lesion. It was followed by HPV-18 (7.4%) and HPV-33 and HPV-39 (4.9% each). HPV-89 was the commonest low-risk type (9.9%). HPV-16/18 were associated with 34.3% of normal, 45.4% of low-grade and 65.7% of high-grade lesions. A wide spectrum of HPV types is seen in north Indian women, with the majority being HPV-16 in all grades of histology. A vaccine against HPV-16 and HPV-18 could prevent two thirds of cases of high-grade cervical neoplasia.

Cytomegalovirus strain diversity in seropositive women.

Infection and reinfection with multiple cytomegalovirus (CMV) strains have been shown to occur in immunocompromised individuals, sexually transmitted disease clinic attendees, and children attending day care centers. To characterize the CMV diversity in healthy seropositive individuals, 16 CMV PCR-positive specimens from 113 seropositive women were analyzed for glycoprotein gN and gB genotypes by cloning, followed by nucleotide sequencing of the plasmid DNA and/or restriction fragment length polymorphism (RFLP). The results showed that most (93.7%) of the PCR-positive specimens contained multiple gN and/or gB genomic variants, suggesting that the majority of women were infected with more than one virus strain. The results also showed that the RFLP technique might not be sufficiently sensitive to detect all of the genomic variants present in a sample.