Introduction of rotavirus vaccination in Palestine: An evaluation of the costs, impact, and cost-effectiveness of ROTARIX and ROTAVAC

Critical Analysis of Economic Evaluation of the Childhood Rotavirus Vaccination in Low- and Lower-Middle-Income Countries: A Systematic Review

OBJECTIVES

To identify, critically appraise, and summarize the use of different methods and results of economic evaluations to assess the efficiency of rotavirus vaccination programs in low- and lower-middle-income countries.

METHODS

A systematic literature search was performed in 3 bibliographic databases, including PubMed, ProQuest, Cochrane Library, and Science Direct (Elsevier) journal website, using key search terms. The study selection process was based on predefined inclusion criteria. The search results were presented using the research flow diagram based on guidelines of PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis). The quality assessment of the selected studies was carried out using the CHEERS (Consolidated Health Economic Evaluation Reporting Standards) checklist.

RESULTS

A total of 21 studies were selected for review. All the studies, except 1, reported rotavirus vaccination to be a cost-effective intervention and a high-impact strategy to reduce substantial rotavirus disease burden. A decision analysis model was considered appropriate by all studies, although there were variabilities in the analytic horizon used. Lack of country-level data was highlighted by most studies. Multiples of gross domestic product of respective countries were used as a threshold to interpret cost-effectiveness.

CONCLUSIONS

Rotavirus vaccination was found to be cost-efficient in most settings, including complex humanitarian emergencies. The use of thresholds for interpreting incremental cost-effectiveness ratios and lack of local-level disease incidence and cost of illness data remains a point of contention. Lack of reporting probabilistic sensitivity analysis renders limited robustness to study results.

Rotavirus vaccine product switch in Ghana: An assessment of service delivery costs, switching costs, and cost-effectiveness

Ghana introduced rotavirus vaccine (ROTARIX 1-dose presentation) into the routine national immunization program in 2012 and switched to a different product (ROTAVAC 5-dose presentation) in 2020. ROTAVAC has a lower price per dose (US$0.85 versus US$2.15 for ROTARIX) and smaller cold chain footprint but requires more doses per regimen (three versus two). This study estimates the supply chain and service delivery costs associated with each product, the costs involved in switching products, and compares the cost-effectiveness of both products over the next ten years. We estimated the supply chain and service delivery costs associated with ROTARIX and ROTAVAC (evaluating both the 5-dose and 10-dose presentations) using primary data collected from health facilities in six of the 14 regions in the country. We estimated the costs of switching from ROTARIX to ROTAVAC using information collected from key informant interviews and financial records provided by the government. All costs were reported in 2020 US$. We used the UNIVAC decision-support model to evaluate the cost-effectiveness (US$ per disability-adjusted life-year (DALY) averted from government and societal perspectives) of ROTARIX and ROTAVAC (5-dose or 10-dose presentations) compared to no vaccination, and to each other, over a ten-year period (2020 to 2029). We ran probabilistic sensitivity analyses and other threshold analyses. The supply chain and service delivery economic cost per dose was $2.40 for ROTARIX, $1.81 for ROTAVAC 5-dose, and $1.76 for ROTAVAC 10-dose. The financial and economic cost of switching from ROTARIX to ROTAVAC 5-dose was $453,070 and $883,626, respectively. Compared to no vaccination, the cost per DALY averted was $360 for ROTARIX, $298 for ROTAVAC 5-dose, and $273 for ROTAVAC 10-dose. ROTAVAC 10-dose was the most cost-effective option and would be cost-effective at willingness-to-pay thresholds exceeding 0.12 times the national GDP per capita ($2,206 in the year 2020). The switch from ROTARIX to ROTAVAC 5-dose in 2020 was cost-saving. Rotavirus vaccination is highly cost-effective in Ghana. A switch from ROTAVAC 5-dose to ROTAVAC 10-dose would be cost-saving and should be considered.

Lessons Learned and Future Perspectives for Rotavirus Vaccines Switch in the World Health Organization, Regional Office for Africa

BACKGROUND

Following the World Health Organization (WHO) recommendation, 38/47 countries have introduced rotavirus vaccines into the program of immunization in the WHO Regional Office for Africa (WHO/AFRO). Initially, two vaccines (Rotarix and Rotateq) were recommended and recently two additional vaccines (Rotavac and Rotasiil) have become available. However, the global supply challenges have increasingly forced some countries in Africa to switch vaccine products. Therefore, the recent WHO pre-qualified vaccines (Rotavac, Rotasiil) manufactured in India, offer alternatives and reduce global supply challenges related to rotavirus vaccines; Methods: Using a questionnaire, we administered to the Program Managers, Expanded Program for Immunization, we collected data on vaccine introduction and vaccine switch and the key drivers of the decisions for switching vaccines products, in the WHO/AFRO. Data was also collected fromliterature review and the global new vaccine introduction status data base maintained by WHO and other agencies.

RESULTS

Of the 38 countries that introduced the vaccine, 35 (92%) initially adopted Rotateq or Rotarix; and 23% (8/35) switched between products after rotavirus vaccine introduction to either Rotavac (n = 3), Rotasiil (n = 2) or Rotarix (n = 3). Three countries (Benin, Democratic Republic of Congo and Nigeria) introduced the rotavirus vaccines manufactured in India. The decision to either introduce or switch to the Indian vaccines was predominately driven by global supply challenges or supply shortage. The withdrawal of Rotateq from the African market, or cost-saving for countries that graduated or in transition from Gavi support was another reason to switch the vaccine; Conclusions: The recently WHO pre-qualified vaccines have offered the countries, opportunities to adopt these cost-effective products, particularly for countries that have graduated or transitioning from full Gavi support, to sustain the demand of vaccines products.

Rotavirus Infection and Genotyping in Yantai, Shandong Province, 2017-2019

PURPOSE

Rotavirus (RV) ranked first among infectious diarrhea-causing pathogens in Yantai from 2017 to 2019. This study investigated the seroserotypes of RV in Yantai, Shandong, from 2017 to 2019 to identify the dominant serotypes and explore the epidemic pattern, aiming to effectively reduce the infection rate, better guide vaccination, and help in epidemiological prevention and control.

METHODS

A total of 2227 human diarrhea samples were collected from 2017 to 2019 in Yantai. The VP7 (G serotype) and VP4 (P serotype) genes of 467 RV-positive samples were amplified using two-round nested reverse transcription-polymerase chain reaction for G/P genotyping.

RESULTS

The genotyping results of RV in Yantai from 2017 to 2019 revealed that G9 was the dominant serotype for all G serotypes, P[8] was the dominant serotype for all P serotypes, and G9P[8] was the dominant serotype for all G/P combinations. G9 serotype accounted for 60.84%, 95.65%, and 83.76% of the total RV samples collected in 2017, 2018, and 2019, respectively. P[8] accounted for 75.52%, 94.69%, and 88.89% of the RV-positive samples collected in 2017, 2018, and 2019, respectively. G9P[8] accounted for 60.84%, 94.69%, and 83.76% of the total RV samples collected in 2017, 2018, and 2019, respectively. Of the total 467 samples from 2017 to 2019, G2P[4] accounted for 3.64% (17/467), G3P[8] for 1.28% (6/467), and G1P[8] for 0.86% (4/467).

CONCLUSION

This study revealed the epidemiological characteristics of RV infection and the development pattern of dominant serotypes in Yantai in recent years, guiding the selection of RV vaccines. The prioritization of vaccines containing G9 serotype for infants in Yantai in recent years is recommended.

M. Eljaro Z, Abu-Awwad F, Bozya Y, Hjaija D, Bhat N, Leader T, Ramlawi A, Marzouqa H. Introducing ROTAVAC® to the occupied Palestinian Territories: Impact on diarrhea incidence, rotavirus prevalence and genotype composition

BACKGROUND

Rotavirus infection remains an important cause of morbidity and mortality in children. The introduction of vaccination programs in more than 100 countries has contributed to a decrease in hospitalizations and mortality. This study investigates the epidemiological impact of the rotavirus vaccine ROTAVAC® in the Palestinian Territories, the first country to switch from ROTARIX® to this new vaccine.

METHODS

Clinical surveillance data was collected fromchildren younger than 5attendingoutpatient clinics throughout Gaza withdiarrhea between 2015 and 2020. The incidence of all-cause diarrhea was assessed using an interrupted time-series approach. Rotavirus prevalence was determined at the Caritas Baby Hospital in the West Bank usingELISA on stool specimen of children younger than 5with diarrhea. Genotyping was performed on 325 randomly selected rotavirus-positive samples from January 2015 through December 2020 using multiplex PCR analysis.

RESULTS

Average monthly diarrhea casesdropped by 16.7% annually fromintroduction of rotavirus vaccination in May 2016 to the beginning of the SARS-CoV-2 epidemic in March 2020 for a total of 53%. Case count declines were maintained afterthe switchto ROTAVAC® in October 2018. Rotavirus positivity in stool samples declined by 67.1% over the same period without change followingthe switch to ROTAVAC®. The distribution of predominant genotypes in rotavirus-positive stool samples changed from a pre-vaccination G1P [8] to G9P[8] and G12P[8] during the ROTARIX® period and G2P[4] after the introduction of ROTAVAC®.

CONCLUSION

ROTAVAC® has shown epidemiological impact on par with ROTARIX® after its introduction to the national immunization schedule in the Palestinian Territories. A molecular genotype shift from a pre-vaccination predominance of G1P[8] to a current predominance of G2P[4] requires more long-term surveillance.

Potential impact and cost-effectiveness of injectable next-generation rotavirus vaccines in 137 LMICs: a modelling study

While current live, oral rotavirus vaccines (LORVs) are reducing severe diarrhea everywhere, their effectiveness is lower in high burden settings. Alternative approaches are in advanced stages of clinical development, including injectable next-generation rotavirus vaccine (iNGRV) candidates, which have the potential to better protect children, be combined with existing routine immunizations and be more affordable than current LORVs. In an effort to better understand the real public health value of iNGRVs and to help inform decisions by international agencies, funders, and vaccine manufacturers, we conducted an impact and cost-effectiveness analysis examining 20 rotavirus vaccine use cases. We evaluated several currently licensed LORVs, one neonatal oral NGRV (oNGRV), one iNGRV, and one iNGRV-DTP (iNGRV comprising part of a DTP-containing combination) over a ten-year timeframe in 137 low- and middle-income countries. The most promising use case identified was a high efficacy iNGRV-DTP, predicted to have the lowest vaccine program cost (US$1.4 billion), the highest vaccine benefit (750,000 rotavirus deaths averted, 13 million rotavirus hospital admissions averted, US$ 2.7 billion health-care cost averted), and most favorable cost-effectiveness (cost-saving). iNGRV-DTP vaccine remained the most affordable, safe, and cost-effective option even when it was assumed to have equivalent efficacy to the current LORVs. This study shows that while the development of iNGRVs with superior efficacy to currently licensed LORVs would be ideal, iNGRVs with similar efficacy to LORVs would offer substantial public health value. It also highlights the economic value of accelerating the development of DTP-based combination vaccines that include iNGRV to provide rotavirus protection.

Molecular epidemiology, genetic diversity, and vaccine availability of viral acute gastroenteritis in the middle East and North Africa (MENA) region

Acute gastroenteritis is the cause of considerable mortality and morbidity worldwide, particularly among children under five years in underdeveloped countries. Most acute gastroenteritis (AGE) cases are attributed to viral etiologies, including rotavirus, norovirus, adenovirus, astrovirus, and sapovirus. This paper aimed to determine the prevalence rate of different viral etiologies of AGE in the Middle East and North Africa (MENA) region. Moreover, this paper explored rotavirus phylogenetic relatedness, compared VP7 and VP4 antigenic regions of rotavirus with vaccine strains, and explored the availability of vaccines in the MENA region. The literature search identified 160 studies from 18 countries from 1980 to 2019. The overall prevalence of rotavirus, norovirus, adenovirus, astrovirus, and sapovirus were 29.8 %, 13.9 %, 6.3 %, 3.5 %, and 3.2 % of tested samples, respectively. The most common rotavirus genotype combinations in the MENA region were G1P[8], G9P[9], and G2P[4], whereas GII.4 was the predominant norovirus genotype all of which were reported in almost all the studies with genotyping data. The comparison of VP7 and VP4 between circulating rotavirus in the MENA region and vaccine strains has revealed discrete divergent regions, including the neutralizing epitopes. Rotavirus vaccine was introduced to most of the countries of the MENA region; however, only a few studies have assessed the effectiveness of vaccine introduction. This paper provides a comprehensive update on the prevalence of the different viral agents of AGE in the MENA region.

Impact and cost-effectiveness of rotavirus vaccination in Niger: a modelling study evaluating alternative rotavirus vaccines

OBJECTIVES

To evaluate the cost-effectiveness of alternative rotavirus vaccines in Niger, using UNIVAC, a proportionate outcomes model.

SETTING

The study leverages global, regional and local data to inform cost-effectiveness modelling. Local data were collected as part of a clinical trial taking place in the Madarounfa district, Maradi region, Niger.

PARTICIPANTS

The study models impact of infants vaccination on rotavirus gastroenteritis in children under 5 years of age.

INTERVENTIONS

We compared the use of ROTARIX (GlaxoSmithKline, Belgium), ROTAVAC (Bharat Biotech, India) and ROTASIIL (Serum Institute, India) to no vaccination and to each other over a 10-year period starting in 2021.

RESULTS

We estimated that ROTARIX, ROTAVAC and ROTASIIL would each prevent 13 million cases and 20 000 deaths of children under 5 years over a 10-year period in Niger. Compared with no vaccination, the cost to avert a disability-adjusted life-year was US$146 with ROTARIX, US$107 with ROTASIIL and US$76 with ROTAVAC from the government perspective. ROTAVAC dominated ROTARIX and ROTASIIL (eg, provided similar or higher benefits at a lower cost) and had 90% chance to be cost-effective at a US$100 willingness-to-pay threshold.

CONCLUSIONS

This study can inform decision-making around rotavirus vaccination policy in Niger, demonstrating that ROTAVAC is likely the most cost-effective option. Alternative products (ROTASIIL and ROTARIX) may also be considered by decision-makers if they are priced more competitively, or if their cold chain requirements could bring additional economic benefits.

Impact of rotavirus vaccine implementation on Israeli children: a comparison between pre- and post-vaccination era

BACKGROUND

Worldwide rotavirus vaccination has resulted in a substantial decrease in rotavirus-induced severe gastroenteritis and related hospitalizations among children. Still, the characterization of patients warranting hospitalization needs to be further elucidated. The purpose of the study is to compare the clinical and laboratory features of children hospitalized with acute rotavirus infection before and after the introduction of routine vaccination.

METHODS

This is a retrospective observational study. Participants were pediatric patients who presented to the Bnai Zion Medical Center pediatric emergency department and were diagnosed with rotavirus acute gastroenteritis between 2017 and 2019.

RESULTS

During the pre-vaccination period (2007-2009), 114 infants and young children (median age: 14 months, range: 1-72 months; 59 male, 55 female) were hospitalized for rotavirus-induced acute gastroenteritis with a rate of 11.71 positive rotavirus tests per 1000 emergency room visits. In the post-vaccination period (2012-2019), 168 infants and young children (median age: 17 months, range: 0-84 months; 90 male, 78 female) were hospitalized with a rate of 4.18 positive rotavirus tests per 1000 emergency room visits. There were no statistical differences between the two groups in gender, breast-feeding rates and sibling(s). The proportion of cases with moderate-to-severe dehydration was higher in the post-vaccination children than in the pre-vaccination children.

CONCLUSIONS

Rates of rotavirus-attributed acute gastroenteritis hospitalizations declined from the pre- to the post-vaccination period. Higher rates of dehydration were found in the post-vaccination children. Ongoing surveillance is warranted to better understand the implications of the vaccine.

Understanding Rotavirus Vaccine Efficacy and Effectiveness in Countries with High Child Mortality

Rotavirus claims thousands of lives of children globally every year with a disproportionately high burden in low- and lower-middle income countries where access to health care is limited. Oral, live-attenuated rotavirus vaccines have been evaluated in multiple settings in both low- and high-income populations and have been shown to be safe and efficacious. However, the vaccine efficacy observed in low-income settings with high rotavirus and diarrheal mortality was significantly lower than that seen in high-income populations where rotavirus mortality is less common. Rotavirus vaccines have been introduced and rolled out in more than 112 countries, providing the opportunity to assess effectiveness of the vaccines in these different settings. We provide an overview of the efficacy, effectiveness, and impact of rotavirus vaccines, focusing on high-mortality settings and identify the knowledge gaps for future research. Despite lower efficacy, rotavirus vaccines substantially reduce diarrheal disease and mortality and are cost-effective in countries with high burden. Continued evaluation of the effectiveness, impact, and cost-benefit of rotavirus vaccines, especially the new candidates that have been recently approved for global use, is a key factor for new vaccine introductions in countries, or for a switch of vaccine product in countries with limited resources.

Estimating the cost of COVID-19 vaccine deployment and introduction in Ghana using the CVIC Tool

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Current COVID-19 vaccine supply market means LMICs will have to rely on a combination of different sources/types of vaccines to meet their demand.

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Deployment of COVID-19 vaccine plans in Ghana will cost $348.7–$436.1 million for coverage of 17.5 million of eligible Ghanaians.

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Vaccine cost constitute 78–83% of total cost whereas the total vaccination cost is 0.48–0.60% of the country’s 2020 GDP.

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The WHO-UNICEF CVIC tool is useful for comprehensive COVID-19 vaccine deployment costing and resource planning.

Background

This study estimated cost of COVID-19 vaccine introduction and deployment in Ghana.

Methods

Using the WHO-UNICEF COVID-19 Vaccine Introduction and deployment Costing (CVIC) tool Ghana’s Ministry of Health Technical Working Group for Health Technology Assessment (TWG-HTA) in collaboration with School of Public Health, University of Ghana, organized an initial two-day workshop that brought together partners to deliberate and agree on input parameters to populate the CVIC tool. A further 2–3 days validation with the Expanded Program of Immunization (EPI) and other partners to finalize the analysis was done. Three scenarios, with different combinations of vaccine products and delivery modalities, as well as time period were analyzed. The scenarios included AstraZeneca (40%), Johnson & Johnson (J&J) (30%), Moderna, Pfizer, and Sputnik V at 10% each; with primary schedule completed by second half of 2021 (Scenario 1); AstraZeneca (30%), J&J (40%), Moderna, Pfizer, and Sputnik V at 10% each with primary schedule completed by first half of 2022 (Scenario 2); and equal distribution (20%) among AstraZeneca, J&J, Moderna, Pfizer, and Sputnik V with primary schedule completed by second half of 2022 (Scenario 3).

Results

The estimated total cost of COVID-19 vaccination ranges between $348.7 and $436.1 million for the target population of 17.5 million. These translate into per person completed primary schedule cost of $20.9–$26.2 and per dose (including vaccine cost) of $10.5–$13.1. Again, per person completed primary schedule excluding vaccine cost was $4.5 and $4.6, thus per dose excluding vaccine also ranged from $2.2 – $2.3. The main cost driver was vaccine doses, including shipping, which accounts for between 78% and 83% of total cost. Further, an estimated 8,437–10,247 vaccinators (non-FTEs) would be required during 2021–2022 to vaccinate using a mix of delivery strategies, accounting for 8–10% of total cost.

Conclusion

These findings provide the estimates to inform resource mobilization efforts by government and other partners.

Association of Rotavirus Vaccines With Reduction in Rotavirus Gastroenteritis in Children Younger Than 5 Years: A Systematic Review and Meta-analysis of Randomized Clinical Trials and Observational Studies

IMPORTANCE

Rotavirus vaccines have been introduced worldwide, and the clinical association of different rotavirus vaccines with reduction in rotavirus gastroenteritis (RVGE) after introduction are noteworthy.

OBJECTIVE

To evaluate the comparative benefit, risk, and immunogenicity of different rotavirus vaccines by synthesizing randomized clinical trials (RCTs) and observational studies.

DATA SOURCES

Relevant studies published in 4 databases: Embase, PubMed, the Cochrane Library, and Web of Science were searched until July 1, 2020, using search terms including "rotavirus" and "vaccin*."

STUDY SELECTION

Randomized clinical trials and cohort and case-control studies involving more than 100 children younger than 5 years that reported the effectiveness, safety, or immunogenicity of rotavirus vaccines were included.

DATA EXTRACTION AND SYNTHESIS

A random-effects model was used to calculate relative risks (RRs), odds ratios (ORs), risk differences, and 95% CIs. Adjusted indirect treatment comparison was performed to assess the differences in the protection of Rotarix and RotaTeq.

MAIN OUTCOMES AND MEASURES

The primary outcomes were RVGE, severe RVGE, and RVGE hospitalization. Safety-associated outcomes involved serious adverse events, intussusception, and mortality.

RESULTS

A meta-analysis of 20 RCTs and 38 case-control studies revealed that Rotarix (RV1) significantly reduced RVGE (RR, 0.316 [95% CI, 0.224-0.345]) and RVGE hospitalization risk (OR, 0.347 [95% CI, 0.279-0.432]) among children fully vaccinated; RotaTeq (RV5) had similar outcomes (RVGE: RR, 0.350 [95% CI, 0.275-0.445]; RVGE hospitalization risk: OR, 0.272 [95% CI, 0.197-0.376]). Rotavirus vaccines also demonstrated higher protection against severe RVGE. Additionally, no significant differences in the protection of RV1 and RV5 against rotavirus disease were noted in adjusted indirect comparisons. Moderate associations were found between reduced RVGE risk and Rotavac (RR, 0.664 [95% CI, 0.548-0.804]), Rotasiil (RR, 0.705 [95% CI, 0.605-0.821]), and Lanzhou lamb rotavirus vaccine (RR, 0.407 [95% CI, 0.332-0.499]). All rotavirus vaccines demonstrated no risk of serious adverse events. A positive correlation was also found between immunogenicity and vaccine protection (eg, association of RVGE with RV1: coefficient, -1.599; adjusted R2, 99.7%).

CONCLUSIONS AND RELEVANCE

The high protection and low risk of serious adverse events for rotavirus vaccines in children who were fully vaccinated emphasized the importance of worldwide introduction of rotavirus vaccination. Similar protection provided by Rotarix and RotaTeq relieves the pressure of vaccines selection for health care authorities.

Evaluating the potential economic and health impact of rotavirus vaccination in 63 middle-income countries not eligible for Gavi funding: a modelling study

BACKGROUND

Middle-income countries (MICs) that are not eligible for funding from Gavi, the Vaccine Alliance, have been slow to adopt rotavirus vaccines. Few studies have evaluated the cost-effectiveness and benefit-risk of rotavirus vaccination in these settings. We aimed to assess the potential economic and health impact of rotavirus vaccination in 63 MICs not eligible for funding from Gavi.

METHODS

In this modelling study, we estimated the cost-effectiveness and benefit-risk of rotavirus vaccination in 63 MICs not eligible to Gavi funding. We used an Excel-based proportionate outcomes model with a finely disaggregated age structure to estimate the number of rotavirus gastroenteritis cases, clinic visits, hospitalisations, and deaths averted by vaccination in children younger than 5 years over a 10-year period. We calculated cost-effectiveness ratios (costs per disability-adjusted life-years averted compared with no vaccination) and benefit-risk ratios (number of hospitalisations due to rotavirus gastroenteritis averted per excess hospitalisations due to intussusception). We evaluated three alternative vaccines available globally (Rotarix, Rotavac, and Rotasiil) and used information from vaccine manufacturers regarding anticipated vaccine prices. We ran deterministic and probabilistic uncertainty analyses.

FINDINGS

Over the period 2020-29, rotavirus vaccines could avert 77 million (95% uncertainty interval [UI] 51-103) cases of rotavirus gastroenteritis and 21 million (12-36) clinic visits, 3 million (1·4-5·6) hospitalisations, and 37 900 (25 900-55 900) deaths due to rotavirus gastroenteritis in 63 MICs not eligible for Gavi support. From a government perspective, rotavirus vaccination would be cost-effective in 48 (77%) of 62 MICs considered. The benefit-risk ratio for hospitalisations prevented versus those potentially caused by vaccination exceeded 250:1 in all countries.

INTERPRETATION

In most MICs not eligible for Gavi funding, rotavirus vaccination has high probability to be cost-effective with a favourable benefit-risk profile. Policy makers should consider this new evidence when making or revisiting decisions on the use of rotavirus vaccines in their respective countries.

FUNDING

Bill & Melinda Gates Foundation.

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.

Update on rotavirus vaccine underperformance in low- to middle-income countries and next-generation vaccines

In the decade since oral rotavirus vaccines (ORV) were recommended by the World Health Organization for universal inclusion in all national immunization programs, significant yet incomplete progress has been made toward reducing the burden of rotavirus in low- to middle-income countries (LMIC). ORVs continue to demonstrate effectiveness and impact in LMIC, yet numerous factors hinder optimal performance and evaluation of these vaccines. This review will provide an update on ORV performance in LMIC, the increasing body of literature regarding factors that affect ORV response, and the status of newer and next-generation rotavirus vaccines as of early 2020. Fully closing the gap in rotavirus prevention between LMIC and high-income countries will likely require a multifaceted approach accounting for biological and methodological challenges and evaluation and roll-out of newer and next-generation vaccines.

Product review of the rotavirus vaccines ROTASIIL, ROTAVAC, and Rotavin-M1

Rotavirus is the leading cause of severe dehydrating gastroenteritis and death due to diarrhea among children under 5, causing over 180,000 under-5 deaths annually. Safe, effective rotavirus vaccines have been available for over a decade and are used in over 98 countries. In addition to the globally available, WHO-prequalified ROTARIX (GSK) and RotaTeq (Merck), several new rotavirus vaccines have attained national licensure - ROTAVAC (Bharat Biotech) and ROTASIIL (Serum Institute of India), licensed and manufactured in India and now WHO-prequalified, and Rotavin-M1 (PolyVac), licensed and manufactured in Vietnam. In this review, we summarize the available clinical trial and post-introduction evidence for these three new orally administered rotavirus vaccines. All three vaccines have demonstrated safety and efficacy against rotavirus diarrhea, although publicly available preclinical data are limited in some cases. This expanding product landscape presents a range of options to optimize immunization programs, and new presentations of each vaccine are currently under development.