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Congenital cytomegalovirus infection (cCMV) is a major cause of childhood hearing loss and neurodevelopmental delay. Identification of newborns with cCMV allows provision of beneficial interventions. However, most infants with cCMV have subclinical infection and go undiagnosed. Thus, expanded newborn CMV testing is increasingly recommended. Saliva...
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... 51,52 This makes early identification of all infants with cCMV through universal screening critically important, however convenient testing platforms (eg, high throughput PCR) using DBS are limited by their lower sensitivity, which may result in up to a 20% to 30% false negative rate as compared to point-of-care saliva or urine testing. 27,53,54 Long-term developmental outcomes in children with cCMV vary widely, 17 with emerging research showing increased risk of vestibular dysfunction, coordination difficulties and autism spectrum disorder. 55 Even with timely hearing rehabilitation with hearing aids or cochlear implants, some children with cCMV and SNHL may be unable to utilize listening and spoken language as their primary means of communication, although other significant benefits of hearing may be present. ...
It is estimated that 1 in every 200 US newborns has congenital cytomegalovirus (cCMV). Delayed identification of cCMV in newborns precludes timely intervention to mitigate sequelae of the infection such as hearing loss and other neurological complications. Newborn testing for cCMV enables appropriate diagnosis and intervention by multidisciplinary teams to properly manage the immediate sequelae of cCMV, avoid unnecessary additional testing that can result from delayed diagnosis, and monitor for future complications. It is the position of the American Cochlear Implant Alliance, the National CMV Foundation, and the American Academy of Otolaryngology–Head and Neck Surgery that universal newborn cCMV screening is necessary to best accomplish these goals.
... Awareness efforts also need not be limited to women of childbearing age, but also the village of people surrounding them, including their partners, public health officials, healthcare providers, and government health agencies. With recent innovations in CMV diagnostics [14,15] and vaccines [16], and with a heightened understanding about the potential lifelong impact of cCMV [17][18][19], an appeal was made to the audience that all individuals invested in the study of CMV should work together to expand shared goals to extend beyond raising awareness to enacting policies that result in behavioral changes that directly prevent the infection from occurring in the first place. ...
Congenital cytomegalovirus (cCMV) is the most common infectious cause of disability in children. The major theme of this National Institute of Allergy and Infectious Diseases (NIAID) workshop, “CMV Vaccine Development—How Close Are We?”, was to report progress on the development of a pre-conception vaccine that could confer protective immunity for women of child-bearing age. Such a vaccine could result in a reduced cCMV disease burden, although other populations, including solid organ transplant and hematopoietic stem cell transplant patients, could benefit as well. To frame the compelling need for a cCMV vaccine, a keynote lecture by Dr. Megan Pesch, immediate past-president of the National CMV Foundation and a leading cCMV researcher from the University of Michigan, was given. This manuscript provides a summary of Dr. Pesch’s presentation from this workshop, which was written as the introductory conference report for the meeting.
... Some rapid molecular techniques have demonstrated appropriate sensitivity and specificity in detecting CMV in newborns [17]. Our research group recently performed a validation study of a point-of-care rapid molecular CMV test (Alethia-LAMP-CMV ® amplification assay) in saliva pools of five samples, which had a high concordance compared with the reference technique [18]. ...
Background: Several screening strategies for identifying congenital CMV (cCMV) have been proposed; however, the optimal solution has yet to be determined. We aimed to determine the prevalence of cCMV by universal screening with saliva pool testing and to identify the clinical variables associated with a higher risk of cCMV to optimize an expanded screening strategy. Methods: We carried out a prospective universal cCMV screening (September/2022 to August/2023) of 2186 newborns, analyzing saliva samples in pools of five (Alethia-LAMP-CMV®) and then performed confirmatory urine CMV RT-PCR. Infants with risk factors (small for gestational age, failed hearing screening, HIV-exposed, born to immunosuppressed mothers, or <1000 g birth weight) underwent expanded screening. Multivariate analyses were used to assess the association with maternal/neonatal variables. Results: We identified 10 infants with cCMV (prevalence: 0.46%, 95% CI 0.22–0.84), with significantly higher rates (2.1%, 95% CI 0.58–5.3) in the high-risk group (p = 0.04). False positives occurred in 0.09% of cases. No significant differences in maternal/neonatal characteristics were observed, except for a higher prevalence among infants born to non-Chilean mothers (p = 0.034), notably those born to Haitian mothers (1.5%, 95% CI 0.31–4.34), who had higher odds of cCMV (OR 6.82, 95% CI 1.23–37.9, p = 0.04). Incorporating maternal nationality improved predictive accuracy (AUC: 0.65 to 0.83). Conclusions: For low-prevalence diseases such as cCMV, universal screening with pool testing in saliva represents an optimal and cost-effective approach to enhance diagnosis in asymptomatic patients. An expanded screening strategy considering maternal nationality could be beneficial in resource-limited settings.
... Other means include the use of anti-CMV immunoglobulin and/or leukocyte filtration treatment of breast milk [57]. Ongoing monitoring of CMV infection in at-risk populations while breastfeeding, such as weekly PCR testing of saliva, can help to identify infants who might benefit from "preventive" treatment at an early stage [58,59]. ...
Bronchopulmonary dysplasia (BPD) is the most common serious complication of very preterm infants (VPI) or very low birth weight (VLBW) infants. Studies implicate viral infections in etiopathogenesis. The aim of this study was to summarize the relationship between viral infections and BPD through a systematic review and meta-analysis. We searched PubMed, Embase, the Web of Science Core Collection, and the Cochrane Database on December 19, 2023. We included observational studies that examined the association between viral infections and BPD in preterm infants. We extracted data on study methods, participant characteristics, exposure assessment, and outcome measures. We assessed study risk of bias using the Newcastle-Ottawa Scale (NOS). We included 17 and 15 studies in the qualitative review and meta-analysis, respectively. The meta-analysis showed a significant association between viral infection and BPD diagnosed at 36 weeks postmenstrual age (odds ratio (OR): 2.42, 95% confidence interval: 1.89–3.09, 13 studies, very low certainty of evidence). In a subgroup analysis of specific viruses, cytomegalovirus (CMV) proved to be significantly associated with BPD diagnosed at 36 weeks postmenstrual age (OR: 2.34, 95% confidence interval: 1.80–3.05, 11 studies). We did not find an association between viral infection and BPD diagnosed on the 28th day of life, probably due to the small sample size of the included prospective studies.
Conclusion: Viral infections, especially CMV, are associated with an increased risk of BPD in preterm infants. Methodologically reliable prospective studies with large samples are needed to validate our conclusions, and high-quality randomized controlled studies are needed to explore the effect of prevention or treatment of viral infections on the incidence of BPD. What is Known:
• Studies have attempted to identify viral infections and bronchopulmonary dysplasia in preterm infants; however, results have been inconsistent.
What is New:
• Systematic demonstration that viral infections, particularly cytomegalovirus, are positively associated with bronchopulmonary dysplasia diagnosed in preterm infants at the 36th week of postmenstrual age.
• The importance of screening for viral infections in preterm infants, especially cytomegalovirus. More high-quality studies should be produced in the future to investigate the causal relationship between viral infections and bronchopulmonary dysplasia.
... Some rapid molecular diagnostic techniques have shown high sensitivity and specificity in newborns for CMV detection. The Alethia-LAMP-CMV ® amplification assay is a point of care loop-mediated isothermal amplification (LAMP) technology with the ability to provide results in less than an hour and has reported 100% and 99.8% positive and negative agreement with saliva real-time PCR (CMV RT-PCR), respectively [8]. This technique may be useful for the diagnosis of cCMV in a more rapid manner and with a lower level of infrastructure requirements. ...
... Sample size estimation and statistical analysis Sample size was determined based on the study by Gantt et al. [8]. A minimum of 1,000 negative prospective CMV samples and a minimum of 5 positive prospectively collected samples were required to be tested to achieve the prespecified Negative Percent Agreement (NPA) of 95%, with a lower 95% confidence interval bound of 85% and to achieve 95% Positive Percent Agreement (PPA), with a lower 95% CI bound of 85%, respectively. ...
... On the other hand, pooling saliva samples to study cCMV has shown accuracy in previous studies [9,22,23], with the potential to reduce costs and turnaround time. New point-of-care platforms for cCMV diagnosis allow to advance screening programs in centers where molecular biology laboratories are not available, mainly in low-income countries settings [8]. ...
Universal congenital cytomegalovirus (cCMV) screening in saliva is increasingly recommended. The aim of our study was to correlate the performance of a point-of-care rapid molecular test with CMV real time PCR (CMV RT-PCR) detection, using saliva pool-testing in newborns under a universal screening strategy. Saliva swabs were prospectively collected from newborns < 21 days old and tested by Alethia-LAMP-CMV assay in pools of 5 samples. In positive pools, subjects were tested individually and by saliva and urine CMV RT-PCR. A subset of negative pools were studied with both techniques and viral loads in whole blood were determined in positive patients. From 1,642 newborns included in 328 pools, 8 were confirmed by urine CMV RT-PCR, (cCMV prevalence 0,49%). The PPA and NNA of the pooled saliva Alethia-LAMP-CMV testing were 87,5% and 99,8% with a negative and positive predictive value of 99,9% and 77,7%, respectively. Two false positives were detected (0,12%). A subset of 17 negative pools (85 samples), studied by saliva CMV RT-PCR, showed 100% concordance.
Conclusion: CMV pool-testing using a rapid molecular test in saliva proved feasible when compared to PCR gold standards. This strategy could improve cost-effectiveness for cCMV universal neonatal screening, based on the low prevalence of the infection and could be a more affordable approach in less developed regions with reduced detection capacity. What is Known:
• cCMV is the most frequent congenital infection and a leading nongenetic cause of sensorineural hearing loss and brain disease.
• Universal screening could allow early detection of congenitally infected infants, improving clinical outcome.
• Saliva PCR is the preferred and non-invasive test for newborn cCMV screening.
What is New:
• The feasibility of a universal cCMV screening by pool-testing in saliva using a rapid test in pools of 5 samples.
• PPA and NPA were 87,5 and 99,8% compared to CMV PCR in urine.
• This strategy could be relevant specially in LMIC where detection capacity is reduced and could improve cost-effectiveness.
• cCMV prevalence in our center was 0,49%.
... Several molecular tests for CMV are FDA cleared/approved for determining viral load in plasma specimens, and laboratory-developed tests (LDTs) have been used to detect CMV in various sample types. Only one test is FDA cleared and commercially available for testing newborn saliva swab samples (10). Unfortunately, the positive predictive value of saliva testing for detection of actual cCMV infection is low due to the potential for contamination from breastmilk or maternal genital secretions, and an initial positive result requires confirmation using a urine specimen (11)(12)(13). ...
Cytomegalovirus (CMV) is the most common virus associated with congenital infection worldwide and is a major cause of sensorineural hearing loss (SNHL) and developmental delay. Up to 90% of infants with congenital CMV (cCMV) infection are asymptomatic at birth, making the diagnosis challenging. Postnatal diagnosis involves testing newborn saliva and/or urine collected before 21 days of life to confirm cCMV infection. This multicenter study evaluated the performance of the Simplexa Congenital CMV Direct real-time PCR assay for the qualitative detection of CMV in newborn saliva (n = 2,023) and urine (n = 1,797) specimens. Compared to two PCR/bidirectional sequencing assays, the Simplexa Congenital CMV Direct assay demonstrated positive percent agreement (PPA) and negative percent agreement (NPA) of 98.6% and 99.9%, respectively, for saliva samples and a PPA of 97.8% and an NPA of 99.9% for urine specimens. Overall concordance was κ = 0.98 or near perfect compared to the composite reference methods with both sample types. By 95% probit analysis, the limit of detection (LoD) using the AD-169 reference strain was 350 ± 12 copies/mL in urine. The LoDs of saliva swabs in either 1 mL or 3 mL of transport medium were 274 ± 12 copies/mL and 300 ± 14 copies/mL, respectively. The Simplexa Congenital CMV Direct assay can be applied to both saliva and urine specimens collected from newborns less than 21 days of age to rapidly and reliably identify CMV infection.
... [19][20][21][22] Saliva CMV PCR is somewhat less sensitive and specific (92% to 98%, and 92% to 99%, respectively) because of falsepositives (0.03% to 0.1%) from CMV shedding in breastmilk. 19,21,23,24 As such, saliva specimens must be collected at least 30 minutes after breastmilk consumption, and any positive result should be confirmed with a urine PCR. 25 To date there are no commercially available highthroughput urine or saliva CMV PCR assays in the United States. Lastly, single primer PCR testing for CMV in dried blood spots has variable sensitivity (between 38.3% to 76.8% in published reports). ...
Congenital cytomegalovirus (cCMV) affects approximately 1 in every 200 US infants and can be associated with long-term neurodevelopmental sequelae, including sensorineural hearing loss, cerebral palsy, and intellectual disability. As cCMV is infrequently diagnosed based on clinical suspicion alone, newborn cCMV screening programs have been gaining traction, especially hearing-targeted programs which only test infants who fail their newborn hearing screen. cCMV screening programs raise unique ethical dilemmas of both under- and over-diagnosis of cCMV. In this Ethics Rounds, we present a case in which the parents of a child with symptomatic cCMV that was not recognized until 4 years of age urge the birth hospital to implement a cCMV screening program. We then ask a parent-clinician, a medical ethicist and pediatrician, and a primary care pediatrician to comment on how they would advise the hospital administration and consider the ethical and clinical implications of a cCMV screening program. The commentaries herein arrive at differing conclusions about cCMV screening. The first highlights the developmental advantages of early cCMV detection, supporting a broad approach to treatment beyond antiviral medication alone. The second explores cCMV screening from the perspective of newborn screening as a public health program, noting shortcomings in available testing platforms, and raising concerns about overdiagnosis and overtreatment. The final commentary challenges the risks of undue parental anxiety and vulnerable child syndrome as a barrier to screening, instead considering cCMV screening as a controlled opportunity to understand and support the experiences of affected children and their families.
... At present, Alethia CMV molecular assay is an accurate method for identifying CMV infection in neonates' saliva sample. Given its simplicity, Alethia has become a suitable assay for CMV testing of neonatal saliva [85]. ...
... Saliva appears an alternative yet less invasive type of sample for newborn cCMV screening [84]. There are currently not many easy-to-use commercial tests for an accurate diagnosis and Alethia CMV molecular assay is one of the newly available tests on neonatal saliva [85]. According to manufacturer's instructions, saliva swabs can be Therefore, this study verifies the effects of storage period and various temperature conditions in detection of CMV from saliva samples using this particular molecular assay. ...
... In this study, we used Alethia CMV molecular assay. Alethia CMV assay is proved to be accurate, simple and appears suitable for CMV testing using neonatal saliva [85]. ...
... e recommended diagnosis of newborn CMV infection is by molecular assay of either urine or saliva samples collected within the first 2-3 weeks after birth [15]. In this study, we used Alethia CMV molecular assay for CMV testing using neonatal saliva [16]. ...
Introduction. Congenital cytomegalovirus (cCMV) is a common cause of neurodevelopmental delays and sensorineural hearing loss of infants, yet the prevalence of cCMV and the associated factors in Ethiopia are not studied. Hence, this study was to assess the prevalence and associated factors of cCMV in Southern Ethiopia. Methodology. A mother-newborn pair cross-sectional study was conducted at Hawassa University Comprehensive and Specialized Hospital, Ethiopia. Newborn’s saliva sample was tested for cCMV using Alethia CMV molecular assay. Mothers’ serum was tested serologically for anti-CMV IgM and IgG by EUROIMMUN ELISA. Pregnant women responded to a questionnaire about their previous and current obstetric history and sociodemographic characteristics. The chi-square (χ²) test and independent-sample t-test were used to determine the associations between infections and possible risk factors; then, potential variables were screened for multivariable analysis. Results. A total of 593 mother-newborn pairs were assessed. CMV was detected in 14 of 593 newborn saliva swabs (2.4%; 95% CI 1.2–3.7). As assessed by CMV IgM-positive results, maternal CMV seropositivity was 8.3% (49/593); thus, the rate of mother-to-child transmission of CMV was 28% (14/49) among CMV IgM-positive women. Congenital CMV infection was significantly associated with maternal exposure through nursery school children in the household, women sharing a feeding cup with children, and any of the detected curable STIs during pregnancy. Birth weight was negatively associated with CMV infection. Maternal age, gravidity, level of education, and sharing of children feeding utensils were not associated with cCMV infection. Conclusion. A high rate of cCMV infection in the absence of awareness demands further in-depth investigation in Ethiopia. Thus, policymakers must take appropriate action through the antenatal care system for prevention strategies and put in place a constant health education and awareness creation of pregnant women about the causes of infection and hygienic measures.
1. Introduction
Cytomegalovirus (CMV) is the most common congenital viral infection passed from pregnant women to babies during pregnancy [1]. Congenital CMV (cCMV) is a leading cause of neurodevelopmental disabilities, including mental retardation, sensorineural hearing loss, and vision impairment [2]. CMV intrauterine transmission follows in both maternal primary infection and nonprimary infection that could be either reinfection with a different CMV strain or reactivation of previous infection [3]. Reactivation can be determined by a variety of viral, environmental, and host factors mainly coexisting with sexually transmitted infections (STI) including HIV [4].
It is known from the available scientific literature [5–8] that STI during pregnancy can increase the reactivation or reinfection rate of maternal CMV infection. Consequently, there will be an expected rise in the sexual transmission of CMV. However, there are not a lot of studies available to address this item more in the depth. Additionally, whether the coinfection during pregnancy increases congenital transmission is not well studied.
Unlike congenital rubella, the maternal immunity acquired against CMV prior to conception does not confer complete protection to the developing fetus [9]. Therefore, a significant rate of cCMV was reported in places where higher rates of maternal seroprevalence were reported. The prevalence of cCMV varies across geographical regions with a lower prevalence in developed countries as compared to Africa, South Asia, and South America [10]. On the other hand, cCMV remains underestimated as a healthcare problem in the entire world while being the main congenital infection. The live birth prevalence of cCMV in developed countries is as low as 0.6 to 0.7% but higher (1–5%) in developing countries [11], where some African countries even reported higher than pooled average like 5.7% in Egypt [12] and 5.9% in South Africa [13].
Despite its burden, cCMV infection often goes undetected at birth because the majority of affected infants are asymptomatic or present with symptoms that are sufficiently nonspecific that do not prompt clinicians to suspect CMV infection. Screening programs, both in pregnant women and in newborns, have not been developed and implemented. Therefore, conducting prevalence cCMV at birth in Ethiopia is important to know the country level burden of the problem and for possible prevention measures. This study is the first in Ethiopia performed on newborn saliva samples. A previous study in Ethiopia conducted using the serological test on cord blood had reported 1.3% of cCMV [14]. The recommended diagnosis of newborn CMV infection is by molecular assay of either urine or saliva samples collected within the first 2-3 weeks after birth [15]. In this study, we used Alethia CMV molecular assay for CMV testing using neonatal saliva [16].
The study aimed to determine the prevalence of cCMV among live births in parallel to the serostatus of their mothers for CMV IgM and IgG. The study also identifies the associating factor and possible efforts required in the prevention of maternal infection to reduce the burden of congenital CMV disease.
2. Methods
2.1. Study Area and Design
A cross-sectional study was conducted on consecutive pregnant women who came for delivery and agreed to participate with their newborns at Hawassa University Comprehensive and Specialized Hospital (HU-CSH) obstetric ward from August to October 2020. The HU-CSH is one of the teaching hospitals serving as a referral center for both public and private hospitals for more than 5 million inhabitants in the southern region and the neighboring region of Ethiopia. The hospital has 500 beds, accommodating around 2,500 pregnant women for antenatal care (ANC) visits and conducting about 5,400 deliveries annually.
2.2. Study Period and Enrollment
Participants were enrolled at the obstetric ward at a time when they came for delivery after obtaining their full consent from August to October 2020. Among the enrolled 600 pregnant women, a total of 608 infants were born (8 twin), of which 11 were stillbirths, 3 were early neonatal deaths, and one was unable to give a sample due to ICU admission. Therefore, 593 neonates were enrolled for assessment of cCMV infection. The pregnant women were screened for CMV IgM and IgG antibodies. Sampling was based on convenience and continued until the intended sample size was reached. Nonresponse during data collection was solved by taking subsequent participants.
2.3. Study Variables
The dependent variable was newborns’ saliva test results for cCMV. The independent variables were sociodemographic characteristics, obstetric history of the mother, and the newborns’ characteristics like birth weight and sex.
2.4. Sociodemographic, Obstetric, and Behavioral Data
The trained midwife at the obstetric ward provided general information about the study to pregnant women who came for delivery. Pregnant women agreeing to join in the study were interviewed using a structured questionnaire translated in Amharic, the language spoken by most people in the study area. The questionnaire was piloted on random pregnant women not included in this study at the same hospital before data collection to ensure the validity and feasibility of the questions. Information related to sociodemographic characteristics (e.g., age, marital status, and educational level), obstetric history, and behavioral data was collected. Newborn’s birth weight and sex were recorded from medical records. According to the World Health Organization (WHO), low birth weight is defined as weight at birth of less than 2,500 g, while preterm is babies born alive before 37 weeks of pregnancy [17].
2.5. Sample Collection and Storage
The midwife-nurse drew a 3 ml blood specimen from each pregnant woman before birth under aseptic condition and considered all current COVID-19 prevention guidelines. Blood samples were processed, and serums were stored at −20°C until analysis for CMV. At the same time interrelated with the first phase of this project, vaginal swab specimen was also collected for the first 350 mothers using Xpert CT/NG Vaginal/Endocervical Specimen Collection Kit (Cepheid, Sunnyvale, California, USA) for curable STI diagnosis [18].
The saliva swabs were collected using nylon-flocked swabs (Copan Italia, Brescia, Italy) according to the instruction guidelines set by Alethia CMV molecular assay at least one hour after the consumption of breast milk [19]. Immediately after collection, samples were shipped to the microbiology laboratory and stored at −20°C until analysis.
2.6. Laboratory Methods
The saliva swab samples were analyzed using the Alethia CMV molecular assay. All laboratory procedures were carried out in accordance with appropriate guidelines and regulations set by the manufacturer [19]. Before the actual assay procedure, the frozen samples were incubated at 19–30°C for 2-3 minutes.
Serologic test of mother’s serum was performed using a commercially available enzyme immunoassay (ELISA) kit (EUROIMMUN Medizinische Labordiagnostika AG, Lübeck, Germany) for anti-CMV IgG and IgM according to the manufacturer’s instructions.
2.7. Data Analysis
Statistical analysis was conducted using SPSS software (version 20.0). The chi-square (χ²) test and independent-sample t-test were used to determine associations between infections and possible risk factors and screen potential variables for multivariable analysis. All explanatory variables with a value less than or equal to 0.2 in the bivariate analysis were included in the multivariable logistic regression model to identify variables that were associated independently. Odds ratios with 95% confidence intervals (CIs) were reported, and a result was considered statistically significant at .
3. Results
3.1. Characteristics of Study Participants
Of the 593 saliva samples tested, 14 specimens (2.36%) were positive for CMV. Among the 14 detected CMV-positive newborns, 8 (2.9%) were male children. The mean birth weight was 2,614 grams for CMV-positive and 3,287 grams for CMV-negative newborns. The mean age of CMV-positive newborns’ mothers was 28.0 ± (SD) 6.0 and the CMV-negative newborns’ mothers was 27.1 ± (SD) 5.1. Eleven out of 14 cCMV-positive newborns were from mothers who have under-five children and nursery school baby in the household. Nearly one-fourth of the women were primigravida. About half of them have nursery school children in their household, 14% (84/593) were currently unmarried, 79% were residing in an urban setting, and 96% were unaware of congenital transmitted infection (Table 1).
Characteristics
Total N (%)
Newborn CMV
value
Positive N (%)
Negative N (%)
Sex of neonate
Male
276 (46.5)
8 (2.9)
268 (97.1)
0.421
Female
317 (53.5)
6 (1.9)
311 (98.1)
Gestational age at birth
Term
529 (89.2)
9 (1.7)
520 (98.3)
0.006
Preterm
64 (10.8)
5 (7.8)
59 (92.2)
Birth weight in grams: mean (SD)
2614.3 (256.7)
3287.4 (550.2)
<0.001
Maternal age (years): mean (SD)
28 (6.0)
27.1 (5.1)
0.506
Marital status
Married
509 (85.8)
11 (2.2)
498 (97.8)
0.435
Currently not married
84 (14.2)
3 (3.6)
81 (96.4)
Residence
Urban
470 (79)
12 (2.6)
458 (97.4)
0.550
Rural
123 (21)
2 (1.6)
121 (98.4)
ANC follow-up during pregnancy
Yes
569 (96)
13 (2.3)
556 (97.7)
0.558
No
24 (4)
1 (4.2)
23 (95.8)
Employed as daycare worker
Yes
40 (6.7)
3 (7.5)
37 (92.5)
0.040
No
553 (93.3)
11 (2.0)
542 (98)
Employed as healthcare worker
Yes
32 (5.4)
2 (6.3)
30 (93.7)
0.156
No
561 (94.6)
12 (2.1)
549 (97.9)
Educational level
Primary and below
217 (36.6)
3 (1.4)
214 (98.6)
0.244
Secondary and above
376 (63.3)
11 (2.9)
365 (97.3)
Gravidity
Primigravida
143 (24.1)
3 (2.1)
140 (97.9)
0.812
Multigravida
450 (75.9)
11 (2.4)
439 (97.6)
Previous adverse pregnancy outcome
Yes
38 (8.5)
1 (2.6)
37 (97.4)
0.812
No
412 (91.5)
10 (2.4)
402 (97.6)
Knowledge on congenitally transmitted infections
Yes
25 (4.2)
1 (4.0)
24 (96.0)
0.586
No
568 (95.8)
13 (2.3)
555 (97.7)
Under-five children in the household
Yes
393 (66.3)
11 (2.8)
382 (97.2)
0.332
No
200 (33.7)
3 (1.5)
197 (98.5)
Nursery school baby in the household
Yes
258 (43.5)
11 (4.3)
247 (95.7)
0.015
No
335 (56.5)
3 (0.9)
332 (99.1)
Sharing a cup with children
Yes
105 (17.7)
5 (4.8)
100 (95.2)
0.085
No
488 (82.3)
9 (1.8)
479 (98.2)
Sharing teeth brush with children
Yes
38 (6.3)
2 (5.3)
36 (94.7)
0.239
No
555 (93.6)
12 (2.2)
543 (97.8)
Sharing eating utensil with children
Yes
88 (14.8)
1 (1.1)
87 (98.9)
0.425
No
505 (85.2)
13 (2.6)
492 (97.4)
Previous adverse pregnancy includes early neonatal death, stillbirth, and preterm birth (n = 450).
... Loop-mediated isothermal amplification (LAMP) has also observed these phenomena [38][39][40][41][42]. This effect was the result, according to the authors, of an optimal salt concentration. ...
Surface Plasmon Resonance (SPR) is widely used in biological and chemical sensing with fascinating properties. However, the application of SPR to detect trace targets is hampered by non-specific binding and poor signal. A variety of approaches for amplification have been explored to overcome this deficiency including DNA aptamers as versatile target detection tools. Hybridization chain reaction (HCR) is a high-efficiency enzyme-free DNA amplification method operated at room temperature, in which two stable species of DNA hairpins coexist in solution until the introduction of the initiator strand triggers a cascade of hybridization events. At an optimal salt condition, as the concentrations of H1 and H2 increased, the HCR signals were enhanced, leading to signal amplification reaching up to 6.5-fold of the detection measure at 30 min. This feature enables DNA to act as an amplifying transducer for biosensing applications to provide an enzyme-free alternative that can easily detect complex DNA sequences. Improvement of more diverse recognition events can be achieved by integrating HCR with a phase-sensitive SPR (pSPR)-tested aptamer stimulus. This work seeks to establish pSPR aptamer system for highly informative sensing by means of an amplification HCR. Thus, combining pSPR and HCR technologies provide an expandable platform for sensitive biosensing.
