Rubella

The impact of sub-national heterogeneities in demography and epidemiology on the introduction of rubella vaccination programs in Nigeria

Rubella infection during pregnancy can result in miscarriage or infants with a constellation of birth defects known as congenital rubella syndrome (CRS). When coverage is inadequate, rubella vaccination can increase CRS cases by increasing the average age of infection. Thus, the World Health Organisation recommends that countries introducing rubella vaccine be able to vaccinate at least 80% of each birth cohort. Previous studies have focused on national-level analyses and have overlooked sub-national variation in introduction risk. We characterised the sub-national heterogeneity in rubella transmission within Nigeria and modelled local rubella vaccine introduction under different scenarios to refine the set of conditions and strategies required for safe rubella vaccine use. Across Nigeria, the basic reproduction number ranged from 2.6 to 6.2. Consequently, the conditions for safe vaccination varied across states with low-risk areas requiring coverage levels well below 80 %. In high-risk settings, inadequate routine coverage needed to be supplemented by campaigns that allowed for gradual improvements in vaccination coverage over time. Understanding local heterogeneities in both short-term and long-term epidemic dynamics can permit earlier nationwide introduction of rubella vaccination and identify sub-national areas suitable for program monitoring, program improvement and campaign support.

Rubella immunity among pregnant women and the burden of congenital rubella syndrome (CRS) in India, 2022

BACKGROUND

India aims to eliminate rubella and congenital rubella syndrome (CRS) by 2023. We conducted serosurveys among pregnant women to monitor the trend of rubella immunity and estimate the CRS burden in India following a nationwide measles and rubella vaccination campaign.

METHODS

We surveyed pregnant women at 13 sentinel sites across India from Aug to Oct 2022 to estimate seroprevalence of rubella IgG antibodies. Using age-specific seroprevalence data from serosurveys conducted during 2017/2019 (prior to and during the vaccination campaign) and 2022 surveys (after the vaccination campaign), we developed force of infection (FOI) models and estimated incidence and burden of CRS.

RESULTS

In 2022, rubella seroprevalence was 85.2% (95% CI: 84.0, 86.2). Among 10 sites which participated in both rounds of serosurveys, the seroprevalence was not different between the two periods (pooled prevalence during 2017/2019: 83.5%, 95% CI: 82.1, 84.8; prevalence during 2022: 85.1%, 95% CI: 83.8, 86.3). The estimated annual incidence of CRS during 2017/2019 in India was 218.3 (95% CI: 209.7, 226.5) per 100, 000 livebirths, resulting in 47,120 (95% CI: 45,260, 48,875) cases of CRS every year. After measles-rubella (MR) vaccination campaign, the estimated incidence of CRS declined to 5.3 (95% CI: 0, 21.2) per 100,000 livebirths, resulting in 1141 (95% CI: 0, 4,569) cases of CRS during the post MR-vaccination campaign period.

CONCLUSION

The incidence of CRS in India has substantially decreased following the nationwide MR vaccination campaign. About 15% of women in childbearing age in India lack immunity to rubella and hence susceptible to rubella infection. Since there are no routine rubella vaccination opportunities for this age group under the national immunization program, it is imperative to maintain high rates of rubella vaccination among children to prevent rubella virus exposure among women of childbearing age susceptible for rubella.

Beyond the acute phase: a comprehensive literature review of long-term sequelae resulting from infectious diseases

Infectious diseases have consistently served as pivotal influences on numerous civilizations, inducing morbidity, mortality, and consequently redirecting the course of history. Their impact extends far beyond the acute phase, characterized by the majority of symptom presentations, to a multitude of adverse events and sequelae that follow viral, parasitic, fungal, or bacterial infections. In this context, myriad sequelae related to various infectious diseases have been identified, spanning short to long-term durations. Although these sequelae are known to affect thousands of individuals individually, a comprehensive evaluation of all potential long-term effects of infectious diseases has yet to be undertaken. We present a comprehensive literature review delineating the primary sequelae attributable to major infectious diseases, categorized by systems, symptoms, and duration. This compilation serves as a crucial resource, illuminating the long-term ramifications of infectious diseases for healthcare professionals worldwide. Moreover, this review highlights the substantial burden that these sequelae impose on global health and economies, a facet often overshadowed by the predominant focus on the acute phase. Patients are frequently discharged following the resolution of the acute phase, with minimal long-term follow-up to comprehend and address potential sequelae. This emphasizes the pressing need for sustained vigilance, thorough patient monitoring, strategic health management, and rigorous research to understand and mitigate the lasting economic and health impacts of infectious diseases more fully.

Updating an Overview of Teratology

In this chapter, the authors aim to update an overview of the principles of teratology, beginning with the definition of teratology, the critical point at which this process occurs, and some of the most common etiological agents that improve our understanding of teratology.Modern teratology has greatly improved in recent years with advances in new methods in molecular biology, toxicology, animal laboratory science, and genetics, increasing our knowledge of ambient influences. Nevertheless, there is a lot to do to reduce the influence of hazardous intervening agents, whether they target our genetics or not, that can negatively affect pregnancy and induce congenital development disorders, including morphological, biochemical, or behavioral defects.Certain agents might indeed be related to certain defects, but we have not been able to identify the cause of most congenital defects, which highlights the importance of finding and testing out new genetics techniques and conducting laboratory animal science to unravel the etiology and pathogenicity of each congenital defect.

Direct and crowding-out effects of a Hepatitis B vaccination campaign

We evaluate the direct and spillover causal effects of a Hepatitis B (HB) vaccination campaign in French schools on the vaccination adherence of the targeted pupils. Using a regression discontinuity design, we show that this campaign created an exogenous shock on vaccination behavior, increasing the HB vaccination rate for children aged 11 and above. At the same time, we show a drop in the measles, mumps, and rubella (MMR) vaccination rate of the targeted pupils and an increase in the parental belief that measles is a benign disease. We interpret these results as a salience effect: the focus on HB vaccination leads to a decrease in the belief that other vaccines are as important. The effect on MMR vaccination was relatively unexpected and may imply a negative externality. Measles is an extremely contagious disease. If the vaccination rate falls, the disease will spread further, raising the question of the net effect of the HB vaccination campaign on the well-being of the population.

Profile of cardiac lesions among laboratory confirmed congenital rubella syndrome (CRS) infants: a nationwide sentinel surveillance, India, 2016-22

Background

The phenotypical profile of cardiovascular malformations in patients with congenital rubella syndrome (CRS) is varied. We aimed to describe the profile of cardiac defects among CRS patients detected in the sentinel CRS surveillance in India during 2016-22.

Methods

Sentinel sites enrolled infants with suspected CRS based on presence of cardiac defects, hearing impairment, eye signs, or maternal history of febrile rash illness. Suspected CRS cases underwent detailed systemic examination, including echocardiography and serological investigation for rubella. Cardiac defects were categorized as 'Simple' or 'Complex' as per the National Heart, Lung, and Blood Institute classification. We compared the distribution of cardiac defects among laboratory confirmed CRS cases and seronegative discarded cases.

Findings

Of the 4578 suspected CRS cases enrolled by 14 sites, 558 (12.2%) were laboratory confirmed. 419 (75.1%) laboratory confirmed cases had structural heart defects (simple defects: n = 273, 65.2%, complex defects: n = 144, 34.4%), with ventricular septal defect (42.7%), atrial septal defect (39.4%), patent ductus arteriosus (36.5%), and tetralogy of Fallot as the commonest defects (4.5%). Laboratory confirmed CRS cases had higher odds of left to right shunt lesions (OR = 1.58, 95% CI: 1.15-2.17). This was mainly on account of a significant association of PDA with CRS (OR = 1.77, 95% CI: 1.42-2.21). Mortality was higher among CRS patients with complex heart defects (HR = 2.04, 95% CI: 1.26-3.30).

Interpretation

Three-fourths of the laboratory confirmed CRS cases had structural heart defects. CRS patients with complex cardiac defects had higher mortality. Detecting CRS infection early and providing timely intervention for cardiovascular defects is critical for the management of CRS patients.

Funding

Ministry of Health and Family Welfare, Govt of India, through Gavi, the Vaccine Alliance.

Rubella virus tropism and single-cell responses in human primary tissue and microglia-containing organoids

Rubella virus is an important human pathogen that can cause neurological deficits in a developing fetus when contracted during pregnancy. Despite successful vaccination programs in the Americas and many developed countries, rubella remains endemic in many regions worldwide and outbreaks occur wherever population immunity is insufficient. Intense interest since rubella virus was first isolated in 1962 has advanced our understanding of clinical outcomes after infection disrupts key processes of fetal neurodevelopment. Yet it is still largely unknown which cell types in the developing brain are targeted. We show that in human brain slices, rubella virus predominantly infects microglia. This infection occurs in a heterogeneous population but not in a highly microglia-enriched monoculture in the absence of other cell types. By using an organoid-microglia model, we further demonstrate that rubella virus infection leads to a profound interferon response in non-microglial cells, including neurons and neural progenitor cells, and this response is attenuated by the presence of microglia.

Dengue-chikungunya infection in the tertiary care hospital of northern India: Cross-sectional latent class cluster analysis in viral infection

Cases of dengue and chikungunya fever are escalating all over India. Both viruses share a common vector, the "Aedes" mosquito. Due to similar clinical symptoms, both the dengue (DENV) and chikungunya (CHIKV) virus can circulate as co-infection. There is very limited data available on dengue-chikungunya co-infection in Uttarakhand, India. The purpose of this study was to determine the seroprevalence of dengue and chikungunya virus infections, as well as their co-infection, in patients presenting with clinical symptoms. Serum samples of clinically suspected patients from the tertiary care hospital of Uttarakhand were collected, and Latent Class Cluster Analysis was performed for clinical profiling. ELISA was performed for DENV and CHIKV. 279 cases were enrolled, out of which 222 (79.5%) came positive for dengue NS1 Ag, 143 (51.2%) for dengue IgM, 98 (35.1%) for IgG followed by 16 (5.7%) of CHIKV IgM, and 4 (1.4%) were NS1 Ag with CHIKV IgM. Among the clinical features, fever (n = 270, 96.8%) was the most common symptom in all suspected dengue and chikungunya cases. Other symptoms like chills (n = 254, 91.0%), arthralgia (n = 241, 86.4%), and headache (n = 240, 86.0%) were present in a significant number. Results showed fewer odds of getting both DENV and CHIKV infection simultaneously, but the risk is still not negligible. This study explores the clinical presentation of the suspected dengue-chikungunya case. The increasing incidence of dengue and chikungunya and their co-infection necessitate the authorities' active surveillance of endemic regions and effective patient care management.

Biological properties of domestic strain vRub-Ant of rubella virus

Introduction. Rubella is a mild infectious disease affecting mainly children and is caused by the rubella virus, part of the Matonoviridae family, genus Rubivirus. Rubella causes congenital rubella syndrome (CRS) and is the main cause of developmental abnormalities, especially blindness and deafness. There is no specific treatment for rubella and CRS. In order to avoid possible complications from rubella infection, a live attenuated rubella vaccine based on the foreign strain of Wistar RA 27/3 rubella virus is used. However, the actual, more effective and preferred vaccine strain the rubella virus for the Russian Federation is considered to be a viral strain of rubella circulating on its territory. The aim of the study was to study the biological properties of the developed domestic cold-adapted strain vRub-Ant circulating in the territory of the Russian Federation. Materials and methods. Following cell cultures were used in the study human embryo lung diploid cell strain LECH-3, transferable cell line from embryonic kidney cells of green monkeys Vero CCL-81 and Vero ECC, human mesenchymal stem cells, human peripheral blood mononuclear cells (PBMC). Cell cultures were grown on a DMEM/F12 nutrient medium with the addition of 5% fetal bovine serum. Swabs from the pharynx and nasal passages from a child with rubella were used as clinical virus-containing material. Monoclonal anti-idiotypic antibodies m(anti-ID)Ab were used to assess the expression level of alpha/beta and gamma interferon receptors (/ and IFN-R)Ab, imitating the biological effects of alpha/beta and gamma interferons (/ and IFN) of humans. The cultural, virological, immunochemical and serological research methods were applied in the study. Results. Attenuation of the vRub-Ant clinical isolate of rubella virus was carried out for 20 consecutive passages on LECH-3 diploid cells at a reduced temperature of 30C. The main biological markers of attenuation were determined to be ts and ca phenotypes. The avirulence of the attenuated viral strain (att-phenotype) was assessed by the level of expression of / and IFN-R. A lower level of / and IFN-R expression was found on the membranes of human PBMC induced by the vaccine strain vRub-Ant in comparison with the parent wild variant of the rubella virus. This trait,the att phenotype, is characteristic of attenuated viral strains. It has been shown that the vaccine strain vRub-Ant has lost neurotropism and was unable to bind to the membrane receptors of the brain (MRB) of guinea pig embryos, unlike its parent rubella virus strain. The high immunogenicity of the domestic cold-adapted strain vRub-Ant was confirmed by high titers of neutralizing rubella antibodies observed in guinea pigs immunized subcutaneously with one vaccination dose of the virus. Conclusion. A domestic attenuated vaccine strain vRub-Ant of the rubella virus that has the main biological markers of attenuation (ts-ca and att phenotypes) has been developed. The vaccine strain vRub-Ant induces a high levels of neutralizing antibodies in guinea pigs following the immunization with a single vaccination dose of the vaccine. The viral strain vRub-Ant has lost its tropism to the MRB of guinea pig embryos, unlike its parent variant.

Interferon Lambda Signals in Maternal Tissues to Exert Protective and Pathogenic Effects in a Gestational Stage-Dependent Manner

Interferon lambda (IFN-λ) (type III IFN) is constitutively secreted from human placental cells in culture and reduces Zika virus (ZIKV) transplacental transmission in mice. However, the roles of IFN-λ during healthy pregnancy and in restricting congenital infection remain unclear. Here, we used mice lacking the IFN-λ receptor (Ifnlr1^-/-) to generate pregnancies lacking either maternal or fetal IFN-λ responsiveness and found that the antiviral effect of IFN-λ resulted from signaling exclusively in maternal tissues. This protective effect depended on gestational stage, as infection earlier in pregnancy (E7 rather than E9) resulted in enhanced transplacental transmission of ZIKV. In Ifnar1^-/- dams, which sustain robust ZIKV infection, maternal IFN-λ signaling caused fetal resorption and intrauterine growth restriction. Pregnancy pathology elicited by poly(I·C) treatment also was mediated by maternal IFN-λ signaling, specifically in maternal leukocytes, and also occurred in a gestational stage-dependent manner. These findings identify an unexpected effect of IFN-λ signaling, specifically in maternal (rather than placental or fetal) tissues, which is distinct from the pathogenic effects of IFN-αβ (type I IFN) during pregnancy. These results highlight the complexity of immune signaling at the maternal-fetal interface, where disparate outcomes can result from signaling at different gestational stages. IMPORTANCE Pregnancy is an immunologically complex situation, which must balance protecting the fetus from maternal pathogens with preventing maternal immune rejection of non-self fetal and placental tissue. Cytokines, such as interferon lambda (IFN-λ), contribute to antiviral immunity at the maternal-fetal interface. We found in a mouse model of congenital Zika virus infection that IFN-λ can have either a protective antiviral effect or cause immune-mediated pathology, depending on the stage of gestation when IFN-λ signaling occurs. Remarkably, both the protective and pathogenic effects of IFN-λ occurred through signaling exclusively in maternal immune cells rather than in fetal or placental tissues or in other maternal cell types, identifying a new role for IFN-λ at the maternal-fetal interface.

TORCH, Anti-cardiolepin, and Anti-phospholipids in Women with Repeated Miscarriage in Mosul City

  Abstract   Background and Objective: The present study aimed to identify a connection between common viral infections and women who had repeatedly miscarriages. Material and Methods: This study is a retrospective study which has been carried out on 2010 records in Mosul city/Iraq, and the patients were all women of child-bearing age (20-35 years old). All of the women had suffered from an abortion at least once before. The target viruses in charge for this study include; Toxoplasma gundi, Cytomegalovirus, Rubella virus, and Herpes virus. Results and Conclusion: The analysis is based on the detection of the anti-bodies which confirmed a negative correlation between antibodies level and active viral infection, together with no clear association between the presence of active infectious status and miscarriage. Additionally, only few positive cases for each individual patient were positive for viral infection.  Hence, the outcome confirmed no clear association between presence of infectious agent and repeated miscarriage. Nonetheless, rubella and cytomegalovirus have shown the highest contribution in this regard.

A study of adult rubella outbreak and its implications on increasing number of women in uniform

Background

Rubella, although a fairly innocuous disease, is a known cause of severe birth defects in newborn. With number of women in uniform on the rise and they being assigned instructional and medical care duties, adult rubella outbreak in a training centre as in this study poses grave threat to them; besides, having disruption potential for their training.

Methods

This study was conducted at an Airmen Training Centre of the Indian Air Force having more than 2500 recruits, in five squadrons. All cases of fever with rash and/or lymphadenopathy were included in the study. The demographic, epidemiological and clinical data of all the cases were analyzed and medical records reviewed.

Results

A total of 31 male recruits reported over 5 days. Among those, 21 cases were from a single squadron to which the index belonged. Twelve women officers were doing instructional duties at the time of outbreak though none became infected. Fever with a rash (90.32%) was the commonest presentation, and lymphadenopathy (64.51%) was the most common sign. Attack rate (AR) with-in the squadron most affected was 4.18%, with an overall AR of 1.23%. The case fatality rate of the disease was nil.

Conclusion

Till the fully immunized cohort of young recruits start getting enrolled, it will be prudent to introduce rubella vaccine to limit the loss of vital training man-hours and prevent the possibility of congenital rubella syndrome in the women instructors and medical caregivers, working in the line of their duty.

Design of a chimaeric antigen and its use in the detection of IgG antibodies against rubella virus

BACKGROUND

Rubella virus (RV) is the causative agent of rubella or German measles. Although most infections cause only mild self-limited measles-like illness, the infection in pregnant women can cause severe foetal malformation or even miscarriage, especially in the first 3 months of pregnancy. Therefore, it is of great practical significance to establish a simple and sensitive RV detection method.

METHODS

The partial epitopes of the E1 and E2 proteins from Rubella Virus were selected as the target sites, the sequence of the selected antigenic sites of the E1 and E2 were linked by a linker. The expression plasmid P6T was constructed by inserting the gene into PET-32A + with a histidine Tag. The P6 protein was induced and expressed in Escherichia coli L21 (DE3) and purified by nickel column affinity. The protein P6 antigen was identified by Western blotting analysis, and an anti-P6 antibody ELISA was established to test known serum samples to evaluate the capability of this method.

RESULTS

After purification, the concentration and purity of the protein P6 were 0.283 mg/mL and more than 80%, respectively. Western blotting analysis showed that the protein P6 could react with rubella virus positive serum. By ELISA, 36 negative sera and 58 positive sera were detected. The coincidence rate, specificity and sensitivity of the ELISA were 86.2%, 88.89% and 84.48%, respectively. The P6 ELISA with a kappa coefficient of 0.715, P < 0.05, indicated excellent consistency.

CONCLUSIONS

The protein P6 with excellent antigenicity obtained from prokaryotic expression followed by chromatography purification could prove useful for early diagnosis of RV infection.

Parity status and the relationship between antenatal rubella serology with obstetric outcome

Routine antenatal rubella serological testing is adopted in many countries. In a population covered by universal childhood rubella immunization for four decades, we have observed an association between pre-eclampsia with maternal rubella seronegativity among multiparous gravidae. This retrospective cohort study was further performed to elucidate the interaction between parity status and rubella seronegativity on obstetric outcome in singleton pregnancies carried to ≥ 24 weeks gestation managed from 1997 to 2019, with the data retrieved from a computerized database used for annual statistics and auditing. Of the 133,926 singleton pregnancies eligible for the study, the 13,320 (9.9%) rubella seronegative gravidae had higher mean booking weight and body mass index (BMI), but shorter height, and higher incidence of advanced age (≥ 35 years), high BMI, short stature, and lower incidence of nulliparas. Univariate analysis showed that adverse obstetric outcomes were more frequently found among the multiparas. On multivariate analysis, there was increased postdated (> 41 weeks) pregnancy irrespective of parity status, while nulliparas had reduced gestational hypertension (aRR 0.714, 95% CI 0.567-0.899) and gestational diabetes (aRR 0.850, 95% CI 0.762-0.950), and multiparas had increased pre-eclampsia (aRR 1.261, 95% CI 1.005-1.582), neonatal death (aRR 2.796, 95% CI 1.243-6.291), and perinatal death (aRR 2.123, 95% CI 1.257-3.587). In conclusion, in a population covered by universal childhood rubella immunization, antenatal rubella seronegativity is associated with increased pre-eclampsia and perinatal loss only in multiparas, suggesting that the rubella seronegativity in these women served as proxy for some form of altered immune response which increases adverse pregnancy outcome.

Rubella epidemiology in the Central African Republic, 2015-2016 and molecular characterization of virus strains from 2008-2016

OBJECTIVES

Rubella cases in the Central African Republic (CAF) are currently identified during measles surveillance. This study aimed to investigate rubella epidemiology between 2015 and 2016 and to provide baseline genotype data for monitoring future rubella control efforts.

METHODS

831 measles IgM negative or equivocal sera from 2015/2016 were tested for rubella IgM antibodies and 350 rubella IgM positive sera collected between 2008 and 2016 were selected for PCR and sequencing.

RESULTS

411 of the 831 sera (49.5%) were rubella IgM positive and most cases (n=391, 95.1%) occurred between January and April. Most patients were between 5 and 9 years old (50.2%) and more than half of the rubella cases (56.7%) originated from the capital Bangui. Genotype information was obtained for 37 of the 350 selected rubella IgM-positive specimens, with the majority of the patients originating from Bangui (n=24, 64.9%) and sequences covering all years except 2009. Phylogenetic analysis identified genotypes 1E (n=12), 1G (n=5) and 2B (n=20), with 2B being detected from 2014 onwards.

CONCLUSIONS

Our study confirmed the important role of rubella as a rash and fever disease in CAF and provided comprehensive data on rubella epidemiology and the first information on rubella genotypes in the country.

Burden of congenital rubella syndrome (CRS) in India based on data from cross-sectional serosurveys, 2017 and 2019-20

Background

India has set a goal to eliminate measles and rubella/Congenital Rubella Syndrome (CRS) by 2023. Towards this goal, India conducted nationwide supplementary immunization activity (SIA) with measles-rubella containing vaccine (MRCV) targeting children aged between 9 months to <15 years and established a hospital-based sentinel surveillance for CRS. Reliable data about incidence of CRS is necessary to monitor progress towards the elimination goal.

Methods

We conducted serosurveys in 2019–20 among pregnant women attending antenatal clinics of 6 hospitals, which were also sentinel sites for CRS surveillance, to estimate the prevalence of IgG antibodies against rubella. We systematically sampled 1800 women attending antenatal clinics and tested their sera for IgG antibodies against rubella. We used rubella seroprevalence data from the current survey and the survey conducted in 2017 among antenatal women from another 6 CRS surveillance sites to construct a catalytic models to estimate the incidence and burden of CRS.

Result

The seroprevalence of rubella antibodies was 82.3% (95% CI: 80.4–84.0). Rubella seropositivity did not differ by age group and educational status. Based on the constant and age-dependent force of infection models, we estimated that the annual incidence of CRS in India was 225.58 per 100,000 live births (95% CI: 217.49–232.41) and 65.47 per 100,000 live births (95% CI: 41.60–104.16) respectively. This translated to an estimated 14,520 (95% CI: 9,225–23,100) and 50,028 (95% CI: 48,234–51,543) infants with CRS every year based on age-dependent and constant force of infection models respectively.

Conclusions

Our findings indicated that about one fifth of women in the reproductive age group in India were susceptible for rubella. The estimates of CRS incidence will serve as a baseline to monitor the impact of MRCV SIAs, as well progress towards the elimination goal of rubella/CRS.

Rubella infection during the first trimester of pregnancy can affect fetus, resulting in spontaneous abortion, stillbirth or birth of a baby with a combination of birth defects known as congenital rubella syndrome (CRS). Vaccination with rubella containing vaccine (RCV) is recommended as one of the strategies for eliminating rubella/CRS. The Southeast Asia region has set a target to eliminate rubella/CRS by 2023. Towards this goal, India completed nationwide immunization campaigns using measles-rubella vaccine during 2017–19, targeting children aged 9 months to <15 years. A case-based surveillance for CRS was initiated in five sentinel hospitals (Phase-1) in 2016 and later expanded to additional 6 sites (Phase-2) in 2019, to estimate burden of CRS and monitor its trend. As an adjunct to CRS surveillance, periodic serologic surveys were also planned to monitor the rubella seroprevalence among the pregnant women. A serosurvey conducted in 2017 indicated that 83.4% pregnant women attending antenatal clinics of Phase-1 sentinel hospitals had IgG antibodies against rubella. The second serosurvey conducted during 2019–20 in 6 Phase-2 sites indicated a comparable seroprevalence of 82.3%. Using seroprevalence data from these two serosurveys, we estimated that the annual incidence of CRS in India was 225.58 per 100,000 live births with constant force of infection and 65.47 per 100,000 live births with age-dependent force of infection models. This incidence rates translated to an estimated 14,520 to 50,028 infants with CRS every year. The estimates of CRS incidence will serve as a baseline to monitor the progress towards the elimination goal of rubella/CRS in India.

Pregnancy and viral infections: Mechanisms of fetal damage, diagnosis and prevention of neonatal adverse outcomes from cytomegalovirus to SARS-CoV-2 and Zika virus

Some maternal infections, contracted before or during pregnancy, can be transmitted to the fetus, during gestation (congenital infection), during labor and childbirth (perinatal infection) and through breastfeeding (postnatal infection). The agents responsible for these infections can be viruses, bacteria, protozoa, fungi. Among the viruses most frequently responsible for congenital infections are Cytomegalovirus (CMV), Herpes simplex 1–2, Herpes virus 6, Varicella zoster. Moreover Hepatitis B and C virus, HIV, Parvovirus B19 and non-polio Enteroviruses when contracted during pregnancy may involve the fetus or newborn at birth. Recently, new viruses have emerged, SARS-Cov-2 and Zika virus, of which we do not yet fully know the characteristics and pathogenic power when contracted during pregnancy.

Viral infections in pregnancy can damage the fetus (spontaneous abortion, fetal death, intrauterine growth retardation) or the newborn (congenital anomalies, organ diseases with sequelae of different severity). Some risk factors specifically influence the incidence of transmission to the fetus: the timing of the infection in pregnancy, the order of the infection, primary or reinfection or chronic, the duration of membrane rupture, type of delivery, socio-economic conditions and breastfeeding. Frequently infected neonates, symptomatic at birth, have worse outcomes than asymptomatic. Many asymptomatic babies develop long term neurosensory outcomes.

The way in which the virus interacts with the maternal immune system, the maternal-fetal interface and the placenta explain these results and also the differences that are observed from time to time in the fetal‑neonatal outcomes of maternal infections. The maternal immune system undergoes functional adaptation during pregnancy, once thought as physiological immunosuppression. This adaptation, crucial for generating a balance between maternal immunity and fetus, is necessary to promote and support the pregnancy itself and the growth of the fetus. When this adaptation is upset by the viral infection, the balance is broken, and the infection can spread and lead to the adverse outcomes previously described. In this review we will describe the main viral harmful infections in pregnancy and the potential mechanisms of the damages on the fetus and newborn.

Monogenic susceptibility to live viral vaccines

Live attenuated viral vaccines (LAV) have saved millions of lives globally through their capacity to elicit strong, cross-reactive and enduring adaptive immune responses. However, LAV can also act as a Trojan horse to reveal inborn errors of immunity, thereby highlighting important protective elements of the healthy antiviral immune response. In the following article, we draw out these lessons by reviewing the spectrum of LAV-associated disease reported in a variety of inborn errors of immunity. We note the contrast between adaptive disorders, which predispose to both LAV and their wild type counterparts, and defects of innate immunity in which parenterally delivered LAV behave in a particularly threatening manner. Recognition of the underlying pathomechanisms can inform our approach to disease management and vaccination in a wider group of individuals, including those receiving immunomodulators that impact the relevant pathways.

The period from prodromal fever onset to rash onset in laboratory-confirmed rubella cases: a cross-sectional study

Background

In resource-limited settings, where rubella is endemic, it is difficult to determine which sporadic case should be tested for rubella. The study aimed to provide useful evidence to help screen rubella cases for real-time reverse transcriptase-polymerase chain reaction (RT-PCR) examination for rubella in resource-limited settings.

Method

Suspected rubella patients identified by a physician and brought to the notice of the Ryugasaki public health center or the Tsuchiura public health center were enrolled from April 2018 through December 2019. The inclusion criterion was a confirmed rubella diagnosis based on laboratory tests. We studied the distribution of the time from the onset of fever until the onset of rash.

Results

The study included 86 cases with simultaneous presentation of fever and rash. Twenty-nine cases had confirmed rubella based on the laboratory diagnosis. Among these, the time from the onset of fever until the onset of rash was limited to − 1 day to 2 days. The number of rubella cases was the highest when the onset of rash was on the following day of the onset of fever. Of the 78 patients who underwent the RT-PCR test, 48% tested positive for rubella among those with a time from the onset of fever to the onset of rash between − 1 day and 2 days (22 out of 46, 95% confidence interval 34–62%); no positive results (0 out of 30, 95% confidence interval - 14%) were seen in patients with a time from fever to rash onset ≥3 days.

Conclusion

The period from the onset of fever to the onset of rash was limited to − 1 day to 2 days among confirmed rubella patients. If the period from onset of fever to the onset of rash was ≥3 days for a patient, the likelihood of rubella was low.

Association between Viral Infections and Risk of Autistic Disorder: An Overview

Autism spectrum disorder (ASD) is a neurodevelopmental condition of the central nervous system (CNS) that presents with severe communication problems, impairment of social interactions, and stereotypic behaviours. Emerging studies indicate possible associations between viral infections and neurodegenerative and neurobehavioural conditions including autism. Viral infection during critical periods of early in utero neurodevelopment may lead to increased risk of autism in the offspring. This review is aimed at highlighting the association between viral infections, including viruses similar to COVID-19, and the aetiology of autism. A literature search was conducted using Pubmed, Ovid/Medline, and Google Scholar database. Relevant search terms included "rubella and autism", "cytomegalovirus and autism", "influenza virus and autism", "Zika virus and autism", "COVID-19 and autism". Based on the search terms, a total of 141 articles were obtained and studies on infants or children with congenital or perinatal viral infection and autistic behaviour were evaluated. The possible mechanisms by which viral infections could lead to autism include direct teratogenic effects and indirect effects of inflammation or maternal immune activation on the developing brain. Brain imaging studies have shown that the ensuing immune response from these viral infections could lead to disruption of the development of brain regions and structures. Hence, long-term follow up is necessary for infants whose mothers report an inflammatory event due to viral infection at any time during pregnancy to monitor for signs of autism. Research into the role of viral infection in the development of ASD may be one avenue of improving ASD outcomes in the future. Early screening and diagnosis to detect, and maybe even prevent ASD are essential to reduce the burden of this condition.

Durability of humoral immune responses to rubella following MMR vaccination

BACKGROUND

While administration of the measles-mumps-rubella (MMR-II®) vaccine has been effective at preventing rubella infection in the United States, the durability of humoral immunity to the rubella component of MMR vaccine has not been widely studied among older adolescents and adults.

METHODS

In this longitudinal study, we sought to assess the durability of rubella virus (RV)-specific humoral immunity in a healthy population (n = 98) of adolescents and young adults at two timepoints: ~7 and ~17 years after two doses of MMR-II® vaccination. Levels of circulating antibodies specific to RV were measured by ELISA and an immune-colorimetric neutralization assay. RV-specific memory B cell responses were also measured by ELISpot.

RESULTS

Rubella-specific IgG antibody titers, neutralizing antibody titers, and memory B cell responses declined with increasing time since vaccination; however, these decreases were relatively moderate. Memory B cell responses exhibited a greater decline in men compared to women.

CONCLUSIONS

Collectively, rubella-specific humoral immunity declines following vaccination, although subjects' antibody titers remain well above the currently recognized threshold for protective immunity. Clinical correlates of protection based on neutralizing antibody titer and memory B cell ELISpot response should be defined.

Prediction of probability of rubella based on eye outcomes (PORBEO Nomogram)-a cross-sectional sentinel surveillance of 1134 infants

INTRODUCTION

Rubella is an important infectious, vaccine-preventable etiology of congenital defects. The aim of the study was to develop a prediction nomogram to assess the probability of an infant being at risk for congenital rubella based on demographics and ophthalmological findings.

METHODS

This was a cross-sectional sentinel surveillance study conducted at 5 centers spanning pan-India and involved 1134 infants. The diagnosis of rubella was made using standard guidelines. For the construction of the prediction model, laboratory-confirmed cases were grouped as "at-risk" (AR) infants and the discarded cases into "not at risk" (NAR) infants. Univariate analysis (p value cut-off < 0.05) followed by multivariate binary logistic regression model development was performed.

RESULTS

The average (median) age of the suspected CRS infants was 3 (IQR 1-6) months, and the average (mean) age of their mothers was 25.8 ± 4.1 years. Out of the total infants, 81 (7.3%) died, 975 (88%) were alive, and 55 (5.0%) were lost to follow-up. The final model showed that the odds of cataract, retinopathy, glaucoma, microcornea, and age of the infant at presentation were 3.1 (2.2-4.3), 4.9(2.3-10.4), 2.7(1.1-5.9), 2.3(1.1-4.7), and 1.1 (1-1.1), respectively, for the AR infant as compared to NAR infant. AUC of final model was 0.68 (95% CI Delong, 0.64-0.72). Bootstrapping for calibration of the model showed satisfactory results. Nomogram, along with a web version, was developed.

CONCLUSION

The developed nomogram would have a wide community-based utilization and will help in prioritizing attention to high-risk children, thereby avoiding loss to follow-up.

Cell Cultures for Virology: Usability, Advantages, and Prospects

Virus detection in natural and clinical samples is a complicated problem in research and diagnostics. There are different approaches for virus isolation and identification, including PCR, CRISPR/Cas technology, NGS, immunoassays, and cell-based assays. Following the development of genetic engineering methods, approaches that utilize cell cultures have become useful and informative. Molecular biology methods allow increases in the sensitivity and specificity of cell cultures for certain viruses and can be used to generate reporter cell lines. These cell lines express specific reporter proteins (e.g., GFP, luciferase, and CAT) in response to virus infection that can be detected in a laboratory setting. The development of genome editing and synthetic biology methods has given rise to new perspectives regarding the design of virus reporter systems in cell cultures. This review is aimed at describing both virology methods in general and examples of the development of cell-based methods that exist today.

Risk factors and etiology of childhood hearing loss: a cohort review of 296 subjects

Background: The association between the Joint Committee on Infant Hearing (JCIH) risk factors and etiology of hearing loss (HL) is not studied well in children.Objectives: To clarify the etiologic causes and evaluate the JCIH risk characteristics of children with HL.Methods: A retrospective study of 296 children with HL born between 2009.01 and 2013.12 in Stokholm. Demographic data, family and medical histories, audiologic results, imaging findings, and genetic results were ascertained and analyzed.Results: In 221 with bilateral hearing loss (BHL), family history and neonatal risk indicators were the most common risks (59 each), followed by syndrome related risks. In 75 with unilateral hearing loss (UHL), craniofacial anomaly was the most common risk, followed by family history. Etiology was established in 93 with BHL, in which syndromic HL accounted for 37.2%, chromosomal aberrations for 21.3%, and environmental causes for 19.1%. Etiology was established in 35 with UHL, in which ear malformation accounted for the most (74.3%), followed by environmental causes (14.3%).Conclusions and significance: Childhood HL can be attributed to a variety of causes with an etiology identifiable in 42.5% of BHL and 46.7% of UHL. BHL and UHL have different patterns of JCIH risk exposure and etiology.

Evaluation of two (02) platforms for chemiluminescence-based detection of anti-rubella IgG antibodies in a sub-Saharan country, Côte d'Ivoire

The diagnosis of rubella is mainly made in pregnant women and the newborn by specific IgG and/or IgM detection. In addition to HAI and ELISA techniques, new immunoanalytical methods have been developed. This study aimed to evaluate two chemiluminescence platforms, Architect i2000SR and Maglumi 800 for rubella biological diagnosis in Côte d'Ivoire. Blood samples were taken from 113 pregnant women aged 15 to 30 in prenatal care. Samples were analyzed for Rubella IgG detection at the NBTS laboratory on the evaluated platforms and the Cobas e601 used as a reference. The majority of women were in their second trimester of pregnancy. Among them, only 13.3% were vaccinated against rubella. The evaluated platforms showed good precision with coefficients of variation >10%. Regarding analytical performances, sensitivities were 97.53% and 96.29% whereas specificities were 100% and 96.88% for Architect I2000SR and Maglumi800, respectively. Both platforms showed good agreement with cobas e601 for antibody levels <200 IU/ml and <350UI/ml for Architect and Maglumi 800, respectively. Findings of the current study revealed that the two platforms have similar features with Cobas e601 and could be used routinely for the serological diagnosis of rubella. However, the results of one platform should not be extrapolated to another.

Vaccine-associated Rubella - a report of two cases and a review of the literature

We report the clinical characteristics of two adult patients, presenting with a typical erythematous rash consistent with rubella disease after MMR vaccination. Both patients had an uncomplicated clinical course and recovered uneventfully. One patient was confirmed to have vaccine-associated rubella via sequencing of virus isolated in viral culture. The other patient had a pharyngeal swab positive for rubella virus PCR, with sequencing matching the vaccine strain. There are few reports of clinical disease from rubella vaccine-strains in the literature. Previous authors have reported severe disseminated vaccine-associated rubella in both immunodeficient and immunocompetent patients. Further study is required to ascertain the incidence, risk factors, and clinical characteristics of this condition; as well as investigate the extent of horizontal transmission to guide infection control recommendations.

A neonate with Langerhans cell histiocytosis presenting as blueberry muffin rash: Case report and review of the literature

In our case report, we discuss a 1-day-old boy presenting with blueberry muffin syndrome diagnosed with Langerhans cell histiocytosis. The diagnosis complicated by an initial difficult-to-interpret biopsy showing only a hint of perifollicular CD1a-positive cells; however, given our team’s strong clinical suspicion of Langerhans cell histiocytosis, a second biopsy of a more mature lesion was done and showed typical histopathology. This case introduces the possibility of perifollicular Langerhans cells early in this condition, demonstrates the importance of appropriate biopsy site selection, and highlights the importance of maintaining a high degree of suspicion when there is poor clinicopathologic correlation. Our case report contains a comprehensive table which reviews the systemic and cutaneous clinical features, as well as the laboratory, pathology, and imaging findings for the differential diagnoses of blueberry muffin baby.

The journey of Zika to the developing brain

Zika virus is a mosquito-borne Flavivirus originally isolated from humans in 1952. Following its re-emergence in Brazil in 2015, an increase in the number of babies born with microcephaly to infected mothers was observed. Microcephaly is a neurodevelopmental disorder, characterised phenotypically by a smaller than average head size, and is usually developed in utero. The 2015 outbreak in the Americas led to the World Health Organisation declaring Zika a Public Health Emergency of International Concern. Since then, much research into the effects of Zika has been carried out. Studies have investigated the structure of the virus, its effects on and evasion of the immune response, cellular entry including target receptors, its transmission from infected mother to foetus and its cellular targets. This review discusses current knowledge and novel research into these areas, in hope of developing a further understanding of how exposure of pregnant women to the Zika virus can lead to impaired brain development of their foetus. Although no longer considered an epidemic in the Americas, the mechanism by which Zika acts is still not comprehensively and wholly understood, and this understanding will be crucial in developing effective vaccines and treatments.

Epidemiology of Congenital Rubella Syndrome (CRS) in India, 2016-18, based on data from sentinel surveillance

Background

Government of India is committed to eliminate measles and control rubella/congenital rubella syndrome (CRS) by 2020. In 2016, CRS surveillance was established in five sentinel sites. We analyzed surveillance data to describe the epidemiology of CRS in India.

Methodology/Principal findings

We used case definitions adapted from the WHO-recommended standards for CRS surveillance. Suspected patients underwent complete clinical examination including cardiovascular system, ophthalmic examination and assessment for hearing impairment. Sera were tested for presence of IgM and IgG antibodies against rubella. Of the 645 suspected CRS patients enrolled during two years, 137 (21.2%) were classified as laboratory confirmed CRS and 8 (1.2%) as congenital rubella infection. The median age of laboratory confirmed CRS infants was 3 months. Common clinical features among laboratory confirmed CRS patients included structural heart defects in 108 (78.8%), one or more eye signs (cataract, glaucoma, pigmentary retinopathy) in 82 (59.9%) and hearing impairment in 51. (38.6%) Thirty-three (24.1%) laboratory confirmed CRS patients died over a period of 2 years. Surveillance met the quality indicators in terms of adequacy of investigation, adequacy of sample collection for serological diagnosis as well as virological confirmation.

Conclusions/Significance

About one fifth suspected CRS patients were laboratory confirmed, indicating significance of rubella as a persistent public health problem in India. Continued surveillance will generate data to monitor the progress made by the rubella control program in the country.

Rubella infection during the first trimester of pregnancy can affect the fetus, resulting in spontaneous abortion, stillbirth or an infant born with a combination of birth defects known as congenital rubella syndrome (CRS). Government of India is committed to eliminate measles and control rubella/CRS and has completed nationwide immunization campaigns using measles-rubella vaccine targeting children aged 9 months to 14 years. A case-based surveillance for CRS is one of the strategies for achieving elimination. The Indian Council of Medical Research and the Ministry of Health and Family Welfare initiated surveillance for CRS in five sentinel sites to estimate the disease burden. During 2016–18, the surveillance sites enrolled 645 suspected CRS patients, 137 (21.2%) were classified as laboratory confirmed CRS and 8 (1.2%) as congenital rubella infection. Common clinical features among laboratory confirmed CRS patients included structural heart defects (78.8%), one or more eye signs (cataract, glaucoma, pigmentary retinopathy (59.9%)) and hearing impairment (38.6%). Thirty-three (24.1%) laboratory confirmed CRS patients died over a period of 2 years. The surveillance data indicated significance of rubella as persistent public health problem in India.

Seroprevalence of measles, mumps, and rubella and genetic characterization of mumps virus in Khartoum, Sudan

BACKGROUND

In Sudan, neither mumps nor rubella vaccines are currently used and comprehensive data on the seroepidemiology of measles, mumps, and rubella (M.M.R), as well as information about circulating mumps virus genotypes, are lacking.

METHODS

In 2015/2016, dried blood spot samples were collected from 294 children, 153 adults from the general population, and 241 healthcare workers (HCWs) from Khartoum. The samples were investigated for M.M.R IgG antibodies using ELISA. Oral fluid samples from 16 clinical mumps cases collected in 2017 were characterized by RT-PCR and sequencing.

RESULTS

The seroprevalence of M.M.R antibodies among children was 93.5%, 63.6%, and 55.8%, while it was 93.5%, 90.8%, and 94.1% among adult volunteers and 99.2%, 97.1%, and 97.9% among HCWs. A high measles seroprevalence was observed among all children age groups, suggesting an effective control programme, while the mumps and rubella seroprevalence increased significantly with age (p<0.001), documenting active wild-type circulation. Our results demonstrated higher M.M.R seropositivity rates and IgG titres in HCWs compared to adult volunteers. Phylogenetic analysis showed the presence of genotype C mumps virus for the first time in Sudan.

CONCLUSIONS

The study findings provided new information on M.M.R epidemiology in Sudan, which may guide future control programmes in the country.

Rubella Virus Infection, the Congenital Rubella Syndrome, and the Link to Autism

Rubella is a systemic virus infection that is usually mild. It can, however, cause severe birth defects known as the congenital rubella syndrome (CRS) when infection occurs early in pregnancy. As many as 8%-13% of children with CRS developed autism during the rubella epidemic of the 1960s compared to the background rate of about 1 new case per 5000 children. Rubella infection and CRS are now rare in the U.S. and in Europe due to widespread vaccination. However, autism rates have risen dramatically in recent decades to about 3% of children today, with many cases appearing after a period of normal development ('regressive autism'). Evidence is reviewed here suggesting that the signs and symptoms of rubella may be due to alterations in the hepatic metabolism of vitamin A (retinoids), precipitated by the acute phase of the infection. The infection causes mild liver dysfunction and the spillage of stored vitamin A compounds into the circulation, resulting in an endogenous form of hypervitaminosis A. Given that vitamin A is a known teratogen, it is suggested that rubella infection occurring in the early weeks of pregnancy causes CRS through maternal liver dysfunction and exposure of the developing fetus to excessive vitamin A. On this view, the multiple manifestations of CRS and associated autism represent endogenous forms of hypervitaminosis A. It is further proposed that regressive autism results primarily from post-natal influences of a liver-damaging nature and exposure to excess vitamin A, inducing CRS-like features as a function of vitamin A toxicity, but without the associated dysmorphogenesis. A number of environmental factors are discussed that may plausibly be candidates for this role, and suggestions are offered for testing the model. The model also suggests a number of measures that may be effective both in reducing the risk of fetal CRS in women who acquire rubella in their first trimester and in reversing or minimizing regressive autism among children in whom the diagnosis is suspected or confirmed.

The Epidemiology of Deafness

Hearing loss is the most common sensory deficit worldwide. It affects ∼5% of the world population, impacts people of all ages, and exacts a significant personal and societal cost. This review presents epidemiological data on hearing loss. We discuss hereditary hearing loss, complex hearing loss with genetic and environmental factors, and hearing loss that is more clearly related to environment. We also discuss the disparity in hearing loss across the world, with more economically developed countries having overall lower rates of hearing loss compared with developing countries, and the opportunity to improve diagnosis, prevention, and treatment of this disorder.

Preclinical study of safety and immunogenicity of combined rubella and human papillomavirus vaccines: Towards enhancing vaccination uptake rates in developing countries

Rubella vaccine was not part of national immunization programs (NIP) in several countries in the Middle East and North Africa (MENA), South-East Asia (SEA), and South Africa regions until the year 2000. Therefore, immunization coverage of females older than 20 years old in these countries has been the focus of national campaigns for rubella elimination in developing countries. Vaccines against human papillomavirus (HPV) are not part of NIPs in developing countries. To enhance the advantages of rubella-directed immunization campaigns and to increase HPV vaccine uptake in developing countries, this study aimed to test the stability, potency, efficacy and safety of a combined rubella and HPV vaccine. Female BALB/c mice were immunized subcutaneously with proposed combined HPV16/HPV18 VLP and rubella vaccine at weeks (W) 0, 3 then with HPV vaccine at W 7. Immunized mice developed antigen-specific antibodies against rubella and HPV significantly higher than mice immunized with rubella or HPV vaccine alone. The combined vaccine induced significantly higher splenocyte proliferation than control groups. In addition, pro-inflammatory cytokines IL-4, IL-6, IL-2, and IFNγ levels were significantly higher in mice immunized with the combined vaccine than control groups. Overall, the combined vaccine was safe and immunogenic offering antibody protection as well as eliciting a cellular immune response against rubella and HPV viruses in a single vaccine. This combined vaccine can be of great value to females above 20 years old in the SEA, MENA and South Africa regions offering coverage to rubella vaccine and a potential increase in HPV vaccine uptake rates after appropriate clinical testing.

The role of viral infections in the development of autoimmune diseases

The exact aetiology of most autoimmune diseases remains unknown, nonetheless, several factors contributing to the induction or exacerbation of autoimmune reactions have been suggested. These include the genetic profile and lifestyle of the affected individual in addition to environmental triggers such as bacterial, parasitic, fungal and viral infections. Infections caused by viruses usually trigger a potent immune response that is necessary for the containment of the infection; however, in some cases, a failure in the regulation of this immune response may lead to harmful immune reactions directed against the host's antigens. The autoimmune attack can be carried out by different arms and components of the immune system and through different possible mechanisms including molecular mimicry, bystander activation, and epitope spreading among others. In this review, we examine the data available for the involvement of viral infections in triggering or exacerbating autoimmune diseases in addition to discussing the mechanisms by which these viral infections and the immune pathways they trigger possibly contribute to the development of autoimmunity.

Life-Threatening Infections Due to Live-Attenuated Vaccines: Early Manifestations of Inborn Errors of Immunity

Live-attenuated vaccines (LAVs) can protect humans against 12 viral and three bacterial diseases. By definition, any clinical infection caused by a LAV that is sufficiently severe to require medical intervention attests to an inherited or acquired immunodeficiency that must be diagnosed or identified. Self-healing infections can also result from milder forms of immunodeficiency. We review here the inherited forms of immunodeficiency underlying severe infections of LAVs. Inborn errors of immunity (IEIs) underlying bacille Calmette-Guérin (BCG), oral poliovirus (OPV), vaccine measles virus (vMeV), and oral rotavirus vaccine (ORV) disease have been described from 1951, 1963, 1966, and 2009 onward, respectively. For each of these four LAVs, the underlying IEIs show immunological homogeneity despite genetic heterogeneity. Specifically, BCG disease is due to inborn errors of IFN-γ immunity, OPV disease to inborn errors of B cell immunity, vMeV disease to inborn errors of IFN-α/β and IFN-λ immunity, and ORV disease to adaptive immunity. Severe reactions to the other 11 LAVs have been described yet remain "idiopathic," in the absence of known underlying inherited or acquired immunodeficiencies, and are warranted to be the focus of research efforts. The study of IEIs underlying life-threatening LAV infections is clinically important for the affected patients and their families, as well as immunologically, for the study of the molecular and cellular basis of host defense against both attenuated and parental pathogens.

Modelling a Supplementary Vaccination Program of Rubella Using the 2012⁻2013 Epidemic Data in Japan

From 2012-2013, Japan experienced a major epidemic of rubella, involving a total of 12,614 rubella cases and 45 confirmed cases of congenital rubella syndrome (CRS). One of the contributory factors in this outbreak may have been that the majority of adult males remained unvaccinated. To plan for a supplementary immunization program (SIP) to elevate the herd immunity level, it is critical to determine the required amount of vaccine and identify the target age groups among males for the SIP. The present study aimed to answer these policy questions, employing a mathematical model and analyzing epidemiological datasets from 2012-2013. Our model allowed us to reconstruct the age- and sex-dependent transmission patterns, and the effective reproduction number during the exponential growth phase in 2013 was estimated to be 1.5. The computed next-generation matrix indicated that vaccinating adult males aged from 20-49 years in 2013, using at least 17 million doses, was considered essential to prevent a major epidemic in the future. The proposed model also indicated that, even with smaller doses of vaccine, the SIP in adult males could lead to a substantial reduction in the incidence of rubella, as well as CRS. Importantly, the present study endorses a substantial background risk of observing another major epidemic from 2018-2019, in which cases may be dominated by adult males aged from 25-54 years, that is, our identified age groups plus a five-year time lag from 2013 to 2018.

Clinical manifestations of congenital rubella syndrome: A review of our experience in Vietnam

Rubella vaccination programs have dramatically reduced the incidence of rubella and congenital rubella syndrome (CRS) in developed countries. However, CRS prevalence is still rising in developing countries where rubella-containing vaccines (RCV) are not included in the immunization program and even in some countries where a part of the population lacks immunity to rubella despite the presence of RCV in the regular immunization program. This review aimed to summarize the clinical features of CRS using data from our studies conducted between 2011 and 2015 in Vietnam, wherein we examined clinical manifestations in Vietnamese children with CRS who were born after the large rubella outbreak of 2011; a series of studies dealing with CRS in North America and Europe after the 1960s epidemic; and those from countries before introduction of RCVs. This review shows that children with CRS have a variety of disabilities such as hearing, visual, developmental, behavioral, cardiac, and endocrine impairments, which have variable severity and may appear in different combinations. Some of these impairments can appear or worsen later in the lives of these children. Physicians should thus complete pediatric, cardiac, auditory, ophthalmologic, and neurologic examinations along with laboratory diagnostic testing soon after birth. These assessments should be repeated during follow-up if congenital rubella infection is suspected in a neonate. Timely intervention for cardiac defects can be lifesaving. Early introduction and continuation of speech, occupational, physical, and behavior therapies and training with appropriate medical interventions by a multidisciplinary team approach are required to maximize quality of life.

Last cases of rubella and congenital rubella syndrome in Spain, 1997-2016: The success of a vaccination program

With a highly immunized population, rubella infection in Spain is so low that the WHO has declared the elimination of rubella. Rubella in pregnant women is also very rare. The objective of this study is to describe the last cases of congenital rubella syndrome reported and recommend actions to maintain the status of the disease as eliminated. The CRS cases reported to the Spanish National Epidemiological Surveillance Network between 1997 and 2016 were studied, and the epidemiological, clinical, diagnostic and maternal characteristics of newborns with CRS described. The incidence of CRS was calculated using Birth Statistics from the Spanish National Statistics Agency (INE). Twenty-three cases of CRS were reported, 70% of which were associated with rubella outbreaks. The most common clinical conditions were heart disease (52.2%), deafness (39.1%) and cataracts (30.4%); 91.3% of cases were confirmed by laboratory testing. 70.0% were born from a non-vaccinated foreign mother, resident in Spain (cumulative rate incidence (CR): 1.1/100,000 births), with mothers coming from Africa (36.0%), Latin America (29.0%), Eastern Europe (21.0%) and Asia (14.0%). Six were born to Spanish mothers (CR: 0.08/ 100,000 births), the last of which were in 2005. The majority of CRS cases were born to unvaccinated immigrant women infected in Spain during rubella outbreaks. Universal vaccination in childhood is the most efficient strategy to prevent rubella. The limited circulation of the virus will, however, quickly lead to a loss of awareness about rubella among clinicians and epidemiologists. It is necessary to maintain protocols capable of identifying signs consistent with rubella in pregnant women and signs suggestive of congenital rubella in newborns.

Sero-prevalence of rubella among pregnant women in India, 2017

BACKGROUND

We conducted a sero-survey among pregnant women attending antenatal clinics of six hospitals which also function as sentinel sites for CRS surveillance, to estimate the prevalence of IgG antibodies against rubella.

METHODS

We systematically sampled 1800 pregnant women attending antenatal clinics and tested their sera for IgG antibodies against rubella. We classified sera as seropositive (titre ≥10 IU/ml), sero-negative (titre <8 IU/ml) or indeterminate (titre 8-9.9 IU/ml) per manufacturer's instructions. In a sub-sample, we estimated the titers of IgG antibodies against rubella. IgG titer of ≥10 IU/mL was considered protective.

RESULTS

Of 1800 sera tested, 1502 (83.4%) were seropositive and 24 (1.3%) were indeterminate and 274 (15.2%) were sero-negative. Rubella sero-positivity did not differ by age group, educational status or place of residence. Three hundred and eighty three (87.8%) of the 436 sera had IgG concentrations ≥10 IU/mL.

CONCLUSION

The results of the serosurvey indicate high levels of rubella sero-positivity in pregnant women. High sero-prevalence in the absence of routine childhood immunization indicates continued transmission of rubella virus in cities where sentinel sites are located.

Infections During Pregnancy

Several infections have unique consequences or considerations in pregnancy. Some common infections such as urinary tract infections, influenza, sexually transmitted diseases, and vaginitis affect pregnant women differently than the general population, can cause pregnancy complications, and require treatments that are safe in pregnancy. Infections such as hepatitis B and C and human immunodeficiency virus can be transmitted vertically and therefore management focuses on decreasing perinatal transmission. Certain infections can be transmitted in utero and cause congenital infections. Classically, these were grouped together as the TORCH infections, although now several others, including varicella virus, parvovirus, and Zika virus, have also been recognized.

Seroprevalence of Zika virus and Rubella virus IgG among blood donors in Rwanda and in Sweden

Seroprevalence studies provide information on the susceptibility to infection of certain populations, including women of childbearing age. Such data from Central Africa are scarce regarding two viruses that cause congenital infections: Zika virus (ZIKV), an emerging mosquito-borne infection, and Rubella virus (RuV), a vaccine-preventable infection. We report on the seroprevalence of both ZIKV and RuV from Rwanda, a country without any known cases of ZIKV, but bordering Uganda where this virus was isolated in 1947. Anti-ZIKV-specific and anti-RuV-specific immunoglobulin G (IgG) antibodies were analyzed by enzyme-linked immunosorbent assay (ELISA) in serum samples from 874 Rwandan and 215 Swedish blood donors. Samples positive for IgG antibodies against ZIKV were examined for viral RNA using real-time reverse transcription polymerase chain reaction (RT-qPCR). The seroprevalence of ZIKV IgG in Rwanda was 1.4% (12/874), of which the predominance of positive findings came from the Southeastern region. All anti-ZIKV IgG-positive samples were PCR-negative. Among 297 female blood donors of childbearing age, 295 (99.3%) were seronegative and thus susceptible to ZIKV. All Swedish blood donors were IgG-negative to ZIKV. In contrast, blood donors from both countries showed high seroprevalence of IgG to RuV: 91.2% for Rwandan and 92.1% for Swedish donors. Only 10.5% (31/294) of female donors of childbearing age from Rwanda were seronegative for RuV. In Rwanda, seroprevalence for ZIKV IgG antibodies was low, but high for RuV. Hence, women of childbearing age were susceptible to ZIKV. These data may be of value for decision-making regarding prophylactic measures.

Seroepidemiology Study of Cytomegalovirus and Rubella among Pregnant Women at St. Paul's Hospital Millennium Medical College, Addis Ababa, Ethiopia

BACKGROUND

Maternal cytomegalovirus (CMV) and rubella infections have adverse neonatal outcomes. Both CMV and rubella are more widespread in developing countries and in communities with lower socioeconomic status. The aim of this study was to investigate sero-prevalence of CMV and rubella infection and associated possible risk factors.

METHOD

Using cross sectional study design a total of 200 pregnant women were consecutively recruited starting from June and July 2014. Blood samples were collected, and structured questions were used to gather socio-demographic and risk factor related data. ELISA was used to detect CMV (IgG, IgM) and rubella IgM. SPSS version 20 was used to analyze the data, and regression was also performed.

RESULTS

Out of 200 pregnant women, 88.5%, 30(15.5%) and 4(2.0%) were CMV-IgG, CMV-IgM, and rubella-IgM positive, respectively. Women who were immune/positive only for IgG were 73.5%. The second group was those with primary infection [IgG (+) plus IgM (+)] and this consisted of 15.0% participants. Eleven percent of the participants were at high risk for primary infection during their pregnancy. One pregnant woman was identified as having a recent primary infection. In this study, no statistically significant association was detected between CMV infection with idependent factors (p-value>0.05).

CONCLUSION

In addition to detection of high prevalence of CMV, detecting recent infection of rubella worsens the outcome of the disease. Rubella vaccine should be taken into consideration after large scale surveillance. However, screening of all pregnant women for CMV infection may not be cost-effective as in the countries with high seropositivity.

Rubella natural immunity among adolescent girls in Tanzania: the need to vaccinate child bearing aged women

BACKGROUND

Rubella primary infection during early stages of pregnancy is associated with high risk of congenital Rubella syndrome (CRS). Prevention of CRS in the resource-limited countries requires multiple strategies. Here, we document the data on the magnitude of Rubella natural immunity among adolescent girls which is a crucial group in devising effective control strategies to prevent CRS.

METHODS

A cross sectional study involving 397 adolescent girls was conducted in the city of Mwanza involving five secondary schools. Socio-demographic and other relevant information were collected using pre-tested data collection tool. Rubella IgG antibodies were determined using enzyme immunoassay. The presence of Rubella IgG titers of >10 IU/ml indicated natural immunity.

RESULTS

The mean age of the study participants was 15.18 ± 1.48 years. Of 397 girls, 340 (85.6%) and 57 (14.4%) were from secondary schools representing peri-urban and rural areas, respectively. Out of 397 girls, 90.4% (95% CI: 87-93) were found to be naturally immune with median Rubella IgG antibodies titers of 56.7 IU/ml interquartile range (IQR): 40.8-137. The median Rubella IgG antibodies titers were significantly high in adolescent girls from families with high socio-economic status (63.96 vs. 47.13 IU/ml, P < 0.001) and in adolescent girls from peri-urban areas of the city (63.33 vs. 39.9 IU/ml, P < 0.001).

CONCLUSION

The majority of adolescent girls in the city of Mwanza are naturally immune to Rubella virus. There is a need to compare the effectiveness of screening and vaccinating susceptible adolescent girls with the effectiveness of vaccinating all women of childbearing in controlling CRS in low-income countries.

Prevalence of Rubella Antibodies Among Children in the Democratic Republic of the Congo

BACKGROUND

While generally mild in children, rubella infection in early pregnancy can lead to miscarriage, fetal death or congenital rubella syndrome. Rubella vaccination is not yet available as a part of routine immunization in the Democratic Republic of the Congo (DRC), and the burden of infection is unknown.

METHODS

In collaboration with the 2013-2014 DRC Demographic and Health Survey, a serosurvey was carried out to assess population immunity to vaccine-preventable diseases. Dry blood spot samples collected from children 6-59 months of age were processed using the Dynex Technologies Multiplier FLEX chemiluminescent immunoassay platform (Dynex Technologies, Chantilly, VA).

RESULTS

Among the 7195 6- to 59-month-old children, 33% were positive and <1% indeterminate for rubella antibodies in weighted analyses. Seroprevalence was positively associated with age of the child and province, with seropositivity highest in Bandundu (53%) and lowest in Kasai-Oriental (20%). In multivariate analyses, serologic evidence of infection was associated with age of the mother and child, socioeconomic status and geographic location.

CONCLUSIONS

Rubella infection is prevalent among children in the DRC, and while most seroconversion occurs in young children, a significant proportion of children remain at risk and may enter reproductive age susceptible to rubella infection. While not currently in place, implementation of a surveillance program will provide improved estimates of both rubella virus circulation and the burden of congenital rubella syndrome. Such information will play an important role in future policy decisions, vaccine delivery strategies and may provide a basis upon which the effectiveness of rubella antigen introduction may be assessed.

An Overview of Teratology

In this chapter, we provide an overview of the basic principles of teratology, beginning with its definition, the critical point for teratogenesis to occur and the most evident etiological agents to improve the understanding of this science.Teratology is a recent science that began in the early twentieth century, and has greatly improved over the recent years with the advancements in molecular biology, toxicology, animal laboratory science, and genetics, as well as the improvement on the knowledge of the environmental influences.Nevertheless, more work is required to reduce the influence of hazardous products that could be deleterious during pregnancy, thus reducing teratogenic defects in the newborn. While some teratogenic defects are attributed to their agents with certainty, the same for a lot of other such defects is lacking, necessitating consistent studies to decipher the influence of various teratogenic agents on their corresponding teratogenic defects. It is here that the laboratory animal science is of great importance both in the present and in the future.