Expanded Indian National Rotavirus Surveillance Network in the Context of Rotavirus Vaccine Introduction

Potential impact of rotavirus vaccination on reduction of childhood diarrheal disease in India: An analysis of National Family Health Survey-5

Rotavirus is one of the leading causes of diarrhea in infants and young children worldwide. In this study, we investigated the impact of rotavirus vaccination on the prevalence of diarrheal disease among children under five years of age in India. Research on the impact of the rotavirus vaccine on reducing diarrheal disease is therefore important in contributing to the growing body of evidence on the effectiveness of this intervention in improving child health outcomes. We adopted multivariate logistic regression and propensity score matching analysis to examine the association between diarrhea and the rotavirus vaccine. The bivariate analysis finding shows that the prevalence of diarrhea was remarkably higher (9.1%) among children who had not received rotavirus and the prevalence was 7.5%, 7.5%, and 7.2% among children who received one dose, two doses, and three rotavirus doses (all) respectively. The result of multivariate logistic regression shows that children who received all three doses of the rotavirus vaccine were 16% less likely to experience diarrhea compared to those who did not receive any rotavirus vaccine. Our analysis also found that the prevalence of diarrhea decreased significantly in the years following the introduction of the vaccine. The results of this study suggest that the rotavirus vaccine has a significant impact on reducing childhood diarrheal disease in India. These results have the potential to inform policy decisions and enable healthcare professionals to concert their efforts in reducing the diarrheal disease burden and its timely prevention in children. The study will also contribute to the existing literature on the impact of rotavirus vaccination in reducing the prevalence of diarrhea among children in India.

Seasonal pattern in occurrence of rotavirus infection (RV) in diarrheic children, calves and piglets from Bareilly, India

Rapid and reliable diagnosis for diarrhoeal disease is critically important for the differentiation of etiological agents and subsequent suitable treatment modalities. The objective of the study is to reveal the seasonal pattern in the occurrence of rotavirus in diarrheic children, calves and piglets from Bareilly, Uttar Pradesh, India. A total of 115 diarrhoeal samples were collected, out of which 51 were collected during post-monsoon/autumn (September 2018-November 2018) and 64 during the winter season (December 2018-February 2019). The samples were collected from children <5 years (n = 50), piglets <3 months (n = 35) and calves <6 months of age (n = 30). These samples were screened by ribonucleic acid-polyacrylamide gel electrophoresis (RNA-PAGE) and reverse transcriptase-polymerase chain reaction (RT-PCR) by targeting the VP6 gene of rotavirus A (RVA) and the two were compared. In RNA-PAGE 29.4% (5/17), 6.3% (1/16) and 0% (0/18) samples collected from children, calves and piglets, respectively were rotavirus positive during the autumn season while 45.5% (15/33), 21.4% (3/14) and 17.7% (3/17) samples in the winter season. In RT-PCR, 41.2% (7/17), 12.5% (2/16) and 0% (0/18) samples were rotavirus positive in the autumn season while 51.5% (17/33), 28.6% (4/14) and 29.4% (5/17) samples in winter season collected from children, calves and piglets, respectively. On statistical analysis, no significant difference between the season and number of positives in children and calves (p > 0.05) was observed, however in piglets significantly higher number of RVA positives were detected in the winter season than autumn (p < 0.01). The diagnostic test comparison of RNA-PAGE and RT-PCR showed no statistically significant difference in detecting the RVA positives (p > 0.05). Overall the percent positivity showed a seasonal pattern with higher positivity in winter as compared to autumn season.

A phase III randomized, open-label, non-inferiority clinical trial comparing liquid and lyophilized formulations of oral live attenuated human rotavirus vaccine (HRV) in Indian infants

The human rotavirus vaccine (HRV; Rotarix, GSK) is available as liquid (Liq) and lyophilized (Lyo) formulations, but only Lyo HRV is licensed in India. In this phase III, randomized, open-label trial (NCT02141204), healthy Indian infants aged 6–10 weeks received 2 doses (1 month apart) of either Liq HRV or Lyo HRV. Non-inferiority of Liq HRV compared to Lyo HRV was assessed in terms of geometric mean concentrations (GMCs) of anti-RV immunoglobulin A (IgA), 1-month post-second dose (primary objective). Reactogenicity/safety were also evaluated. Seroconversion was defined as anti-RV IgA antibody concentration ≥20 units [U]/mL in initially seronegative infants (anti-RV IgA antibody concentration <20 U/mL) or ≥2-fold increase compared with pre-vaccination concentration in initially seropositive infants. Of the 451 enrolled infants, 381 (189 in Liq HRV and 192 in Lyo HRV group) were included in the per-protocol set. The GMC ratio (Liq HRV/Lyo HRV) was 0.93 (95% confidence interval [CI]: 0.65–1.34), with the lower limit of the 95% CI reaching ≥0.5, the pre-specified statistical margin for non-inferiority. In the Liq HRV and Lyo HRV groups, 42.9% and 44.3% (baseline) and 71.4% and 73.4% (1-month post-second dose) of infants had anti-RV IgA antibody concentration ≥20 U/mL, and overall seroconversion rates were 54.5% and 50.0%. Incidences of solicited and unsolicited adverse events were similar between groups and no vaccine-related serious adverse events were reported. Liq HRV was non-inferior to Lyo HRV in terms of antibody GMCs and showed similar reactogenicity/safety profiles, supporting the use of Liq HRV in Indian infants.

What is the context?

Rotavirus is the most common cause of acute gastronenteritis and contributes to the high number of hospitalizations and deaths in young children worldwide.

Vaccination against rotavirus has led to a significant decrease in rotavirus-related infections.

The human rotavirus vaccine Rotarix (GSK) is currently used as a liquid or lyophilized formulation.

In clinical trials conducted in European and North American infants, the liquid vaccine showed ability to induce immune response and safety comparable to the lyophilized formulation.

Only the lyophilized vaccine is currently marketed in india.

What is new?

We compared the 2-dose liquid and lyophilized human rotavirus vaccines in indian infants in a phase III clinical trial:

The ability to induce immune response for thw liquid formulation was not inferior to that observed for the lyophilized vaccine.

The safety profiles of the 2 formulations were comparable.

Why is this important?

This study shows that the liquid human rotavirus vaccine can be administrated to infants from india.

Tate J, D. Parashar U, Kang G. Rotavirus Strain Distribution before and after Introducing Rotavirus Vaccine in India

In April 2016, an indigenous monovalent rotavirus vaccine (Rotavac) was introduced to the National Immunization Program in India. Hospital-based surveillance for acute gastroenteritis was conducted in five sentinel sites from 2012 to 2020 to monitor the vaccine impact on various genotypes and the reduction in rotavirus positivity at each site. Stool samples collected from children under 5 years of age hospitalized with diarrhea were tested for group A rotavirus using a commercial enzyme immunoassay, and rotavirus strains were characterized by RT-PCR. The proportion of diarrhea hospitalizations attributable to rotavirus at the five sites declined from a range of 56–29.4% in pre-vaccine years to 34–12% in post-vaccine years. G1P[8] was the predominant strain in the pre-vaccination period, and G3P[8] was the most common in the post-vaccination period. Circulating patterns varied throughout the study period, and increased proportions of mixed genotypes were detected in the post-vaccination phase. Continuous long-term surveillance is essential to understand the diversity and immuno-epidemiological effects of rotavirus vaccination.

Rotavirus Diarrhea in Hospitalized Under-5 Children in Madhya Pradesh, India and the Prevalent Serotypes After Vaccine Introduction

OBJECTIVE

To report epidemiology of rotavirus gastroenteritis among under-five children hospitalized for acute diarrhea after the introduction of vaccine in Madhya Pradesh.

METHODS

Children hospitalized for diarrhea between August 2017 and December 2019 were recruited. Stool sample was collected and shipped to Christian Medical College (CMC), Vellore maintaining proper cold chain. Samples were then screened for rotavirus using enzyme immunoassay (EIA). The samples that were positive for rotavirus were further genotyped by reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULTS

Of the 794 stool samples collected, 150 (18.8%) samples were positive for rotavirus. Highest positivity was seen in winter months and in children less than 2 y of age. G3P[8] was found to be the most prevalent serotype.

CONCLUSIONS

The study highlights lowering prevalence of rotavirus gastroenteritis in the authors' region post vaccine introduction. It also highlights the change in prevalent serotypes.

Rotavirus Gastroenteritis in Western Uttar Pradesh, India

OBJECTIVE

To establish hospital-based surveillance to identify cases of rotavirus (RV) among children < 5 y of age hospitalized for acute gastroenteritis (AGE) and to determine the burden and profile of circulating RV genotypes in the region.

METHODS

This study was conducted at a tertiary level hospital in Bijnor district of western Uttar Pradesh, India from January 2018 to January 2020. The duly filled case reporting forms and specimens of all the enrolled children were transported in cold chain to the referral laboratory at Christian Medical College (CMC), Vellore on a monthly basis for testing and storage of stool samples as well as data entry and analysis.

RESULTS

A total of 1055 under-5 children admitted with AGE, were enrolled. Proper stool specimens were collected from 932 children. Rotavirus was found positive in 368 (39.5%) stool specimens. Marked seasonality was observed in RV-positive cases with the highest incidence was noticed during winter months. The 0-11 mo age group had the highest incidence of RV-GE followed by 12-23 mo. G1 (42.08%) was the most frequent G-type whereas G1P[8] (26.23%) was the commonest circulating genotype.

CONCLUSION

The study confirms a significant burden of RV among AGE cases in young children in western Uttar Pradesh. The findings of the study may serve as useful baseline information to the Government of India for assessing vaccine performance after its introduction in the national immunization programmes.

Clinical Profile, Risk-Factors, and Outcome of Rotaviral Diarrhea and Non-rotaviral Diarrhea Among Under-Five Children at Cuttack, Odisha, India

OBJECTIVE

To understand the prevalence of rotavirus diarrhea and its associated clinical and socio-demographic characteristics.

METHODS

The prospective hospital-based study was conducted at SVP Post Graduate Institute of Pediatrics and SCB Medical College, Odisha, India among children under-five years of age from April 2016 to July 2019. From all eligible children admitted at hospital, a case-report form containing information on clinical and socio-demographic characteristics was collected and an attempt was made to collect stool sample. A simple logistic regression method was used to assess factors associated with rotavirus diarrhea.

RESULTS

Of the 1963 children, median (IQR) age was 12 (8-19) mo with a female/male ratio was 1:2.05. The prevalence of rotavirus diarrhea was 36.4% (95% CI, 34.2%-38.6%). Children in the age group of 6-11 (OR 1.64, 95% CI, 1.24-2.18), 12-23 (OR 1.73, 95% CI, 1.31-2.29) mo had higher odds of getting rotavirus diarrhea, compared to those in that of 24-59 mo. The prevalence of wasting, stunting, underweight among children with rotavirus diarrhea was 25.2% (95% CI, 22%-28.4%), 2.1% (95% CI, 1.1%-3.1%), 9.0% (95% CI, 6.8%-11.2%), respectively.

CONCLUSION

The results of this study confirmed that diarrhea remains an important cause of hospitalization in children. Further studies are required in the community for Rotavirus and its genotyping.

Rotavirus Gastroenteritis Hospitalizations Among Under-5 Children in Northern India

OBJECTIVE

To study epidemiological profile, prevalence, and molecular epidemiology of RVGE in hospitalized under-5 children at a tertiary care teaching rural hospital located in sub-Himalayan belt of Northern India.

METHODS

This was a hospital-based surveillance study done over 4 y (2016-2019) including under-5 children hospitalized with acute gastroenteritis (AGE). Demographic and clinical parameters were recorded in a pre-designed performa. After consent, stool samples were collected and sent to Christian Medical College (CMC), Vellore for RV screening by enzyme immunoassay (EIA). Each EIA-positive sample was further subjected to G and P typing using published methods.

RESULTS

Out of total 851 included children, rotavirus gastroenteritis (RVGE) was detected in 23.03% (196/851) cases by EIA. The highest incidence for RVGE-positive cases (40.43%) was observed in 2016 with gradual decline over next 3 y. Maximum cases of diarrhea were observed in 12-23 mo age group along with highest rotavirus detection. G3P[8] was most common genotype (46.94%) found, followed by G1P[8] (13.78%), G2P[4] (4.59%), G1P[6] (8.16%) and G9P[4] (3.57%). Mixed genotype was seen in 13.78% of total cases.

CONCLUSION

This study summarizes the changing trends in the epidemiology of RVGE in Northern India along with the major circulating genotypes postvaccine introduction.

Gastroenteritis in Haryana, India Post Introduction of Rotavirus Vaccine

OBJECTIVE

To evaluate the epidemiology of rotavirus gastroenteritis in Haryana post-introduction of rotavirus vaccine. Expanded National rotavirus surveillance network in India reported high burden of rotavirus diarrhea in India. The Government of India introduced the monovalent rotavirus vaccine made in India by Bharat Biotech in the national immunization programme from 2016 onward along with oral polio vaccine (OPV) and Pentavalent vaccines.

METHODS

A multi-centric, hospital-based surveillance study in the initial vaccine introducing states was started in a phased manner over a period of 3 y. PGIMS, Rohtak is a tertiary care center and was a part of the surveillance from 2016 to 2019. Children aged 0-59 mo admitted with acute gastroenteritis were enrolled into the surveillance and their stool samples were collected. Samples were tested at Christian Medical College (CMC), Vellore to detect rotavirus and reverse transcription-polymerase chain reaction (RT-PCR) was used for G and P typing.

RESULTS

A total of 904 children were enrolled in the present surveillance over a period of 3 y starting 1st July 2016 to 30th June 2019. Stool samples were collected and analyzed for 827 children and out of them 141 samples were positive for rotavirus (17.1%). Maximum rotavirus positivity was observed during the winter months. Rotavirus positivity percentage was observed maximum in 12-23 mo age group. A declining trend was observed in rotavirus positivity from 22.8% in 2016 to 14.5% in 2019. Most common strains of rotavirus isolated were G3P[8] followed by G1P[8].

CONCLUSION

This study highlights that epidemiology of acute gastroenteritis among children less than 5 y of age in Haryana postintroduction of rotavirus vaccination in the state and the decline in rotavirus positivity from 22.8% in 2016 to 14.5% in 2019.

Epidemiology of rotavirus diarrhea among children less than 5 years hospitalized with acute gastroenteritis prior to rotavirus vaccine introduction in India

Background

Rotavirus is an important cause of severe diarrhea requiring hospitalization, accounting for approximately 78,000 deaths annually in Indian children below 5 years of age. We present epidemiological data on severe rotavirus disease collected during hospital-based surveillance in India before the introduction of the oral rotavirus vaccine into the national immunization schedule.

Methods

The National Rotavirus Surveillance Network was created involving 28 hospital sites and 11 laboratories across the four geographical regions of India. From September 2012 to August 2016 children less than 5 years of age hospitalized for diarrhea for at least 6 h, were enrolled. After recording clinical details, a stool sample was collected from each enrolled child, which was tested for rotavirus antigen using enzyme immunoassay (EIA). Nearly 2/3rd of EIA positive samples were genotyped using reverse transcription polymerase chain reaction to identify the G and P types.

Results

Of the 21,421 children enrolled during the 4 years surveillance, 36.3% were positive for rotavirus. The eastern region had the highest proportion of rotavirus associated diarrhea (39.8%), while the southern region had the lowest (33.8%). Rotavirus detection rates were the highest in children aged 6–23 months (41.8%), and 24.7% in children aged < 6 months. Although rotavirus associated diarrhea was seen throughout the year, the highest positivity was documented between December and February across all the regions. The most common rotavirus genotype was G1P[8] (52.9%), followed by G9P4 (8.7%) and G2P4 (8.4%).

Conclusions

There is high burden of rotavirus gastroenteritis among Indian children below 5 years of age hospitalized for acute diarrhea thereby highlighting the need for introduction of rotavirus vaccine into the national immunization program and also for monitoring circulating genotypes.

Genotypic determination of human group A rotaviruses from Goa and Meghalaya states, India

Introduction

Rotavirus is the leading cause of diarrhoea in young children in India, responsible for an estimated 21357 mean numbers of deaths in 2010. Various genotypes of rotaviruses evolved due to mutational changes have been recognized. In this study, we determined the genotypes of rotaviruses involved in diarrhea in Goa and Meghalaya states of India.

Methods

The dsRNA of rotaviruses was extracted from stool samples and detected by Ribonucleic Acid-Polyacrylamide gel electrophoresis (RNA PAGE) and Reverse transcription-polymerase Chain Reaction (RT-PCR) targeting the partial VP7 gene. The full length VP7 and partial VP4 genes of rotavirus strains were amplified by RT-PCR followed by nucleotide sequencing. The RotaC classification tool was used to determine the genotypes.

Results

The positivity of rotavirus by PAGE and RT-PCR was observed to be 43.10% and 39.65% in Goa and 38% and 36% in Meghalaya, respectively. Though long electrophoretic profile was appeared to be the most predominant rotavirus type in circulation in these two states, 96% of long and 84.61% short electropherotype profiles could be detected by RT-PCR. The dsRNA of rotavirus extracted from 36 samples could be transcribed and amplified by beg9end9 primers for G genotyping, while, 41 by con3con2 primers for P genotyping. G1P[8] and G1P[6] genotypes were commonly circulated in Goa and G1P[8] and G1P[4] genotypes in Meghalaya. On nucleotide analysis, 6 samples from Goa showed G1 genotype specificity, while, 3 showed P[8] specificity indicating the G1P[8] rotavirus circulating in Goa. In Meghalaya state, 3 strains showed P[8] and 2 showed P[4] genotype specificity. The majority of the G and P genotypes were closely related to each other and G1 genotypes appeared in two separate clusters, while, P[8] and P[4] appeared in the respective clusters.

Conclusion

The circulation of G1P[8], G1P[6] genotypes in Goa and the presence of G1P[8] and G1P[4] genotypes in Meghalaya was observed.

Aetiology and outcome of acute diarrhoea in children with severe acute malnutrition: a comparative study

OBJECTIVE

To compare the microbiological profile, clinical course and outcome of acute diarrhoea in children aged <5 years having severe acute malnutrition (SAM) with those of children having normal nutritional status.

DESIGN

Cross-sectional comparative study.

SETTING

Tertiary-care hospital catering mainly to the urban poor of East Delhi, India.

PARTICIPANTS

Children aged <5 years (n 140; seventy with SAM (cases) and seventy with normal anthropometry (controls)) with acute diarrhoea (duration < 14 d). Stool samples were collected for conventional culture, microscopy, acid-fast staining, rotavirus and Cryptosporidium antigen detection, and subtyping of diarrhoeagenic Escherichia coli (DEC). We followed-up these children for persistent diarrhoea and subsequent diarrhoeal episode in the next 3 months.

RESULTS

Rotavirus was detected in six (9 %) cases and in fifteen (21 %) controls (P = 0·03; OR = 0·34; 95 % CI 0·12, 0·94). DEC was isolated significantly more in cases compared with controls (93 v. 64 %; P < 0·001; OR = 7·25; 95 % CI 2·57, 20·4). Cryptosporidium was detected in seven (10 %) cases and five (7 %) controls. Total duration of diarrhoea and percentage change in weight after resolution of diarrhoea were comparable between cases and controls. At 3-month follow-up, number of subsequent episodes of diarrhoea and persistent diarrhoea were comparable between the two groups.

CONCLUSIONS

Rotavirus was found significantly less frequently, whereas DEC was detected more frequently in children with SAM in comparison to non-malnourished children. To further reduce diarrhoea-related mortality, preventive and therapeutic interventions need to be designed against organisms causing diarrhoea in children with SAM.

Multicountry Analysis of Spectrum of Clinical Manifestations of Children <5 Years of Age Hospitalized with Diarrhea

After introduction of rotavirus vaccine, other pathogens might become leading causes of hospitalizations for severe diarrhea among children <5 years of age. Our study in 33 hospitals in 7 countries found acute gastroenteritis accounted for most (84%) reported hospitalizations of children with diarrhea. Bloody and persistent diarrhea each accounted for <1%.

Introducing rotavirus vaccine in the Universal Immunization Programme in India: From evidence to policy to implementation

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India became one of the first countries in Asia to introduce rotavirus vaccine.

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Rotavirus vaccine is being expanded to the entire country in a phase wised manner.

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The new vaccine introduction strengthened the programme rather than burdening it.

Background

In 2016, India became one of the first countries in Asia to introduce an indigenously manufactured rotavirus vaccine. However, any new vaccine introduction needs to be meticulously planned to allow for strengthening of the existing immunization systems instead of burdening them.

Methods

The process of rotavirus vaccine introduction in India started with the establishment of National Rotavirus Surveillance Network in 2005 which generated relevant evidence to inform policy level decisions to introduce the vaccine. The preparatory activities started with assessment of health systems and closing any gaps. This was followed by development of vaccine specific training packages and cascade training for programme managers and health workers. The introduction was complemented with strong communications systems and media involvement to allow for good acceptability of the vaccine on the ground. Each step of introduction was led by the government and technically supported by development partners.

Results

India introduced rotavirus vaccine in a phased wise manner. In the first two phases the vaccine has been introduced in nine states of the country accounting for nearly 35% of the annual birth cohort of the country. From March 2016 to November 2017, approximately 13,260,000 rotavirus vaccine doses were administered in the country. The vaccine was well accepted by both the health workers and parents/caregivers.

Conclusion

Rotavirus vaccine introduction in India is an excellent example of how government stewardship with well-defined roles for development partners can allow a new vaccine introduction to be used as a system strengthening activity.

Seasonal variation and etiologic inferences of childhood pneumonia and diarrhea mortality in India

Control of pneumonia and diarrhea mortality in India requires understanding of their etiologies. We combined time series analysis of seasonality, climate region, and clinical syndromes from 243,000 verbal autopsies in the nationally representative Million Death Study. Pneumonia mortality at 1 month-14 years was greatest in January (Rate ratio (RR) 1.66, 99% CI 1.51-1.82; versus the April minimum). Higher RRs at 1-11 months suggested respiratory syncytial virus (RSV) etiology. India's humid subtropical region experienced a unique summer pneumonia mortality. Diarrhea mortality peaked in July (RR 1.66, 1.48-1.85) and January (RR 1.37, 1.23-1.48), while deaths with fever and bloody diarrhea (indicating enteroinvasive bacterial etiology) showed little seasonality. Combining mortality at ages 1-59 months with prevalence surveys, we estimate 40,600 pneumonia deaths from Streptococcus pneumoniae, 20,700 from RSV, 12,600 from influenza, and 7200 from Haemophilus influenzae type b and 24,700 diarrheal deaths from rotavirus occurred in 2015. Careful mortality studies can elucidate etiologies and inform vaccine introduction.

Epidemiology and genetic diversity of group A rotavirus in acute diarrhea patients in pre-vaccination era in Himachal Pradesh, India

Acute gastroenteritis due to Group A rotaviruses remains the leading cause of mortality and morbidity in children in developing countries. India introduced its indigenous rotavirus vaccine Rotavac® in 2016 and Himachal Pradesh (HP) the first state to launch it. The present study aimed to evaluate rotavirus strain diversity associated with AGE prior to vaccine introduction in HP. A total of 331 fecal specimens collected from diarrheic children hospitalized at RPGMC Tanda, HP between July-2014 and June-2016 were screened for RVA by EIA. Rotavirus RNA was extracted by TRIZOL method and analyzed by RNA-PAGE. G/P typing was performed using semi-nested multiplex reverse transcriptase PCR. Rotavirus was detected in 45% (n = 149/331) of diarrheic children, with highest rate observed in the 6-11 months age group (47%). Vomiting was found more frequently associated with RV-infection. Among G-types, G12 was found most prevalent (33.1%) followed by G1 (28.4%), G9 (12.2%), G2 (9.5%), G3 (3.4%) and G10 (2.7%). G4 (0.7%) strains were rarely detected. Among P-types, P[6] was the most prevalent (40.5%) followed by P[8] (29.1%) and P[4] (14.2%). Of note, genotypes G3 and P[11] were detected for the first time in HP. Among G/P combinations, G12P[6] was most prevalent (30.4%) followed by G1P[8] (20.3%), G2P[4] (4.7%), G1P[6] (3.4%) and G3P[8] (2.7%). Interestingly, our study observed high percentage of unusual strains (14.2%) namely G9P[4], G2P[6], G2P[8], G12P[4] and G1P[11]. The regionally common strains G3P[6], G4P[6], G9P[6], G9P[8], G10P[6], G10P[8] and G12P[8] strains were very rarely detected. Of interest, RNA migration pattern of G1P[8] was DS-1 like and genomic heterogeneity was observed within G12P[4] strains with both long and short electropherotypes. Our study highlights rich genetic diversity with emergence of rare rotavirus strains circulating in HP and provides baseline data prior to Rotavac® introduction that will help to gauge the impact of the Rotavac® vaccine in HP.

Occurrence of viral gastroenteritis in children below 5 years: A hospital-based study from Assam, India

Viral gastroenteritis is an important cause of mortality and morbidity in children under 5 years of age. Many a time, these cases go unnoticed causing immense scarcity of data on viral diarrhoea. The study aimed to determine the occurrence of viral gastroenteritis among children below 5 years and the aetiological viral agents. Stool samples were collected from patients suffering from acute gastroenteritis. Real-time polymerase chain reaction was done for detection of rotavirus, adenovirus, norovirus, astrovirus and sapovirus. Viruses were detected in 55% of children. Adenovirus was found to be the most common virus (33.7%), followed by rotavirus infection (28.7%).

Rotavirus vaccine impact assessment surveillance in India: protocol and methods

INTRODUCTION

Rotavirus infection accounts for 39% of under-five diarrhoeal deaths globally and 22% of these deaths occur in India. Introduction of rotavirus vaccine in a national immunisation programme is considered to be the most effective intervention in preventing severe rotavirus disease. In 2016, India introduced an indigenous rotavirus vaccine (Rotavac) into the Universal Immunisation Programme in a phased manner. This paper describes the protocol for surveillance to monitor the performance of rotavirus vaccine following its introduction into the routine childhood immunisation programme.

METHODS

An active surveillance system was established to identify acute gastroenteritis cases among children less than 5 years of age. For all children enrolled at sentinel sites, case reporting forms are completed and a copy of vaccination record and a stool specimen obtained. The forms and specimens are sent to the referral laboratory for data entry, analysis, testing and storage. Data from sentinel sites in states that have introduced rotavirus vaccine into their routine immunisation schedule will be used to determine rotavirus vaccine impact and effectiveness.

ETHICS AND DISSEMINATION

The Institutional Review Board of Christian Medical College, Vellore, and all the site institutional ethics committees approved the project. Results will be disseminated in peer-reviewed journals and with stakeholders of the universal immunisation programme in India.

Sentinel surveillance for rotavirus in children <5 years of age admitted for Diarrheal illness to Yangon Children's Hospital, Myanmar, 2009-2014

BACKGROUND

Rotavirus is the leading cause of severe acute gastroenteritis (AGE) in children <5 years of age in Myanmar. The purpose of this analysis is to report from the sentinel surveillance system for rotavirus gastroenteritis (RVGE), which collects information on the epidemiology and circulating genotypes to assess the disease burden and support vaccine introduction in Myanmar.

METHODS

Prospective, active surveillance for RVGE-associated hospitalizations was conducted during 2009 -2014 at Yangon Children's Hospital. Stool samples collected from children <5 years of age admitted for AGE were screened for rotavirus antigen by ELISA (ProSpecT™ Rotavirus, OXOID-UK). G and P genotyping was performed by reverse transcription polymerase chain reaction.

RESULTS

Overall, 1860/3724 (49.9%) of stool samples tested positive for rotavirus, ranging from 42-56% of hospitalized AGE cases each year. RVGE was predominant in the 6-11 months age group 889/1860 (47.8%) as compared with 12-23 months 633/1860 (34.0%), 0-5 months 226/1860 (12.2 %) and 24-59 months 112/1860 (6.0%). RVGE occurred in a seasonal cycle with peak occurrence in the cold and dry months (November to February), accounting for 65.3% (1151/1763) among enrolled AGE cases. Vomiting (84.1% Vs 67.9%; P < .01), fever (84.5% Vs 75.6%; P < .01) and dehydration (78% Vs 69%; P < .01) were more frequently observed in RVGE than non-RVGE. Genotyping revealed that G1P[8] was predominant from January to June 2009, G12P[8] was predominant throughout 2009-2012 which was replaced in 2012-2013 by G2P[4] and changed again to G1P[8] in 2013-2014 and G9P[8] in late 2014.

CONCLUSIONS

Rotavirus is accounting for approximately half of AGE-associated hospitalizations among children <5 years of age in Myanmar. There is immense diversity of rotavirus strains similar to that reported previously for other countries in the region. Information gained from this surveillance system highlights consideration of rotavirus vaccine introduction into this target population.

Quantifying rotavirus kinetics in the REH tumor cell line using in vitro data

Globally, rotavirus is the most common cause of diarrhea in children younger than 5 years of age, however, a quantitative understanding of the infection dynamics is still lacking. In this paper, we present the first study to extract viral kinetic parameters for in vitro rotavirus infections in the REH cell tumor line. We use a mathematical model of viral kinetics to extract parameter values by fitting the model to data from rotavirus infection of REH cells. While accurate results for some of the parameters of the mathematical model were not achievable due to its global non-identifiability, we are able to quantify approximately the time course of the infection for the first time. We also find that the basic reproductive number of rotavirus, which gives the number of secondary infections from a single infected cell, is much greater than one. Quantifying the kinetics of rotavirus leads not only to a better understanding of the infection process, but also provides a method for quantitative comparison of kinetics of different strains or for quantifying the effectiveness of antiviral treatment.

Genotype distribution of Group A rotavirus from southern India, 2005-2016

Diarrheal disease due to Group A rotaviruses remain a leading cause of mortality and morbidity in the less developed parts of the world. India has started a phased roll out of rotavirus vaccine in the national immunization program. This analysis summarizes the rotavirus genotype strain distribution pre-vaccine introduction in Vellore, India from December 2005 to June 2016. Rotavirus was responsible for 32% of all diarrheal admission to the hospital. G2P[4] was the predominant strain in the initial years and was gradually replaced by G1P[8]. The emergence of G9P[4] replacing G9P[8], and the detection of G12 strains over several years were documented. There was no clear seasonality of disease. These data form the baseline to monitor genotype distribution post-vaccine introduction in Tamil Nadu.

Epidemiological features and genetic characterization of virus strains in rotavirus associated gastroenteritis in children of Odisha in Eastern India

We have studied the clinical characteristics, severity and seasonality of rotavirus infection and prevalent genotypes in 652 non-rota vaccinated children in Odisha in eastern India. P genotypes were analysed for their association with host blood group antigens. P type of the virus is determined by the VP8* gene, and specific recognition of A - type of Histo - blood group antigen by P[14]VP8* has been reported. VP4, VP7 and VP6 genes of commonly identified G1P[8] strain were compared with genes of the same strain isolated from other parts of India, elsewhere and strains used for Rotarix and Rotateq vaccines. In 54.75% of children with gastroenteritis, rota virus was found. 9.65% of children had moderate, 78.07% severe, and 12.28% very severe disease as assessed using the Vesikari scoring system. The incidence of infection was highest during winter months. There was no association between any blood group and specific P genotypes. G1P[8] was the commonest cause of gastroenteritis, followed by G1P[11], G3P[8], G9P[8], G2P[4], G2P[6], G9P[4], G9P[11] and G1P[6]. Predominant G genotypes identified were G1 (72.9%), G9 (10.81%), G2 (8.10%) and G3 (8.10%). Sequence analysis of the VP7 gene, placed the G1P[8] strain in lineage 1 and of VP6 gene placed nine G1P[8] strains in subgroup II and one in subgroup I. The VP7 gene segment of two Odisha G1P[8] strains were found to cluster relatively close to the VP7 sequences of Rotarix vaccine. Antigenic differences were found with vaccine strains. Ten G1P[8] strains sequenced for the VP4 gene had 91-93% nucleotide and 92-96% amino acid identity with Rotateq vaccine P[8]). Rotarix vaccine VP4 had 89-91% nucleotide and 90-92% amino acid identity. Our findings indicate genetic variability of rotavirus strains circulating in the region and are significant, given the introduction of rota vaccination in the State.