Impact of Rotavirus Vaccines on Gastroenteritis Hospitalizations in Western Australia: A Time-series Analysis

BackgroundRotavirus vaccination was introduced into the Australian National Immunisation Program in mid-2007. We aimed to assess the impact of the rotavirus vaccination program on the burden of hospitalizations associated with all-cause acute gastroenteritis (including rotavirus gastroenteritis and non-rotavirus gastroenteritis) in the Aboriginal and non-Aboriginal population in Western Australia.MethodsWe identified all hospital records, between July 2004 and June 2012, with a discharge diagnosis code for all-cause gastroenteritis. Age-specific hospitalization rates for rotavirus and non-rotavirus acute gastroenteritis before and after the introduction of the rotavirus vaccination program were compared. Interrupted time-series models were used to examine differences in the annual trends of all-cause gastroenteritis hospitalization between the two periods.ResultsBetween July 2004 and June 2012, there were a total of 106,974 all-cause gastroenteritis-coded hospitalizations (1,381 rotavirus-coded [15% among Aboriginal] and 105,593 non-rotavirus gastroenteritis-coded [7% among Aboriginal]). Following rotavirus vaccination introduction, significant reductions in rotavirus-coded hospitalization rates were observed in all children aged <5 years (up to 79% among non-Aboriginal and up to 66% among Aboriginal). Among adults aged ≥65 years, rotavirus-coded hospitalizations were 89% (95% confidence interval, 16–187%) higher in the rotavirus vaccination program period. The time-series analysis suggested reductions in all-cause gastroenteritis hospitalizations in the post-vaccination period among both vaccinated and unvaccinated (age-ineligible) children, with increases observed in adults aged ≥45 years.ConclusionsRotavirus vaccination has been associated with a significant decline in gastroenteritis hospitalizations among children. The increase in the elderly requires further evaluation, including assessment of the cost-benefits of rotavirus vaccination in this population.Key words: rotavirus vaccine, acute gastroenteritis, vaccine impact, hospitalizations, time-series     

Impact of rotavirus vaccine on paediatric rotavirus hospitalisation and intussusception in New Zealand: A retrospective cohort study

BackgroundRotavirus results in a significant burden of hospitalisations and deaths globally. Rotavirus vaccine has been used in New Zealand since July 2014. The aim of this study was to assess the safety and effectiveness of RotaTeq® vaccine in New Zealand between 2006 and 2016.MethodsA national cohort study of 723,695 children aged less than 6 years was carried out using linked administrative datasets. Study outcomes were hospitalisation for intussusception, rotavirus, and all-cause gastroenteritis. Intussusception hospitalisation rates were calculated from 2006 to 2016, and rotavirus and all-cause gastroenteritis hospitalisation rates from 2011 to 2016. We examined the effect of RotaTeq® vaccination on rotavirus and all-cause gastroenteritis hospitalisation rates using Poisson regression. Adjusted incidence rate ratios controlled for sex, year of birth, ethnicity, socioeconomic deprivation, and district health board area.ResultsSignificant reductions in the incidence of rotavirus hospitalisation were seen in all age groups, ethnicities, and deprivation following the introduction of RotaTeq®. There was a 92.6% reduction in hospitalisation incidence in the vaccinated cohort (p < 0.0001). There was also a 48% reduction in all-cause gastroenteritis hospitalisation incidence in the vaccinated cohort (p < 0.0001). The average annual intussusception rate in children aged less than 3 years was 26.2 per 100,000, with no significant change over time (p = 0.847).ConclusionsIn New Zealand the introduction of RotaTeq® resulted in a significant reduction in rotavirus hospitalisation, and a halving in all-cause gastroenteritis hospitalisation. There has been no change in the overall incidence of intussusception or clear change in patterns of cases, although intussusception cases did occur within risk period immediately post vaccine.     

A population based study comparing changes in rotavirus burden on the Island of Ireland between a highly vaccinated population and an unvaccinated population

BackgroundRotavirus infection is a leading cause of gastroenteritis in infants and children globally. Reductions in rotavirus activity have been observed following introduction of rotavirus vaccination programmes, however a reductions have also been reported in some unvaccinated countries.The Island of Ireland incorporates the two jurisdictions Northern Ireland (NI) and the Republic of Ireland (IE). Both have similarities in climate, demography, morbidity and mortality but distinct health administrations and vaccination policies. Rotarix was added to the childhood immunisation programme in NI on the 1 July 2013. IE have not introduced routine rotavirus vaccination to date.The aim of this population based ecological study was to evaluate the impact of the rotavirus vaccine on burden of rotavirus disease in NI, and to compare with IE as an unvaccinated control population. This will help determine if the changes seen were due to the rotavirus vaccine, or due to confounding factors.MethodsA number of population based measures of disease burden were compared in both jurisdictions pre-vaccine (six years; 2007/08–2012/13) and post-vaccine (two years; 2013/14–2014/15). The data sources included national rotavirus surveillance data based on laboratory reports/notifications; hospital admission data; and notifications of gastroenteritis in under 2 year olds.ResultsIn the post-vaccination period, rotavirus incidence in NI dropped by 54% while in IE it increased by 19% compared to the pre-vaccine period. Notifications of gastroenteritis in under 2 s in NI declined by 53% and hospital admissions in under 5 year olds in NI declined by 40% in the post vaccine period.ConclusionsThis natural experiment demonstrated a significant reduction in rotavirus disease activity post-vaccine introduction in NI with associated reductions in healthcare utilisation, with a concurrent increase in rotavirus disease activity in the non-vaccinated population in IE. These findings support rotavirus vaccination as an effective measure to reduce childhood morbidity.     

Burden of rotavirus disease in young children in Iceland – Time to vaccinate?

BackgroundAcute gastroenteritis poses a significant burden on young children, families, health care facilities and societies. Rotavirus is the most common pathogen, but rotavirus infections are vaccine preventable. Information on the epidemiology of gastroenteritis in Icelandic children has until now not been available and rotavirus vaccination is currently not offered to Icelandic infants. The objective of this study was to assess the burden of rotavirus acute gastroenteritis in young children in Iceland and determine the potential benefit of adding rotavirus vaccine to the Icelandic childhood immunization schedule.MethodsFor a two-year period, children < 6 years old attending a children’s emergency department for acute gastroenteritis were recruited at the Children’s Hospital in Reykjavík, Iceland. Demographic information and Vesikari scores were registered. Stool samples were analyzed for pathogens. Duration of symptoms, treatment given, and secondary household infections were among the collected information. Annual cost of the infections in young children was estimated based on health care expenditures and lost days of parental work.Results325 children were included in the study, 75% of which were ≤ 24 months old. A pathogen was identified in 80% of cases, of which rotavirus was identified in 54%. Rotavirus caused a more severe disease than other pathogens, more often leading to fluid treatment in the emergency department and admissions. Median duration of rotavirus-illness was six days and caused a median of four days lost from work by parents. The estimated annual cost of rotavirus acute gastroenteritis was €2.9 million.ConclusionsRotavirus causes significant disease burden in young children. Although rarely life-threatening in high income countries, the costs for society are substantial. The inclusion of rotavirus vaccine in the national immunization schedule will reduce the disease burden and would be cost-saving in Iceland.     

Evaluating rotavirus vaccination in England and Wales. Part I. Estimating the burden of disease

Rotavirus is a major cause of gastroenteritis in young children. New vaccines for rotavirus are now available and countries need to establish the health and economic burden of rotavirus disease to assess whether vaccine introduction is advisable. This study assesses the fraction of acute gastroenteritis in children under 5 years that may be attributable to rotavirus using multiple linear regression. Results suggest around 45% of hospitalisations, 25% of GP consultations, 27% of NHS Direct calls and 20% of accident and emergency (A&E) attendances for acute gastroenteritis in this age group may be attributable to rotavirus. The annual incidence is estimated to be 4.5 hospitalisations, 9.3 A&E consultations, and 28-44 GP consultations per 1000 children under five years of age. The cost to the health service is estimated to be pound 14.2m per annum. Rotavirus vaccination has the potential to reduce this burden of disease. This study provides a sound basis on which to make this assessment and serves as a baseline against which any reductions that do occur if vaccination is introduced can be measured against.     

Measuring indirect effects of rotavirus vaccine in low income countries

Widespread introduction of rotavirus vaccines has led to major reductions in the burden of rotavirus gastroenteritis worldwide. Vaccine effectiveness is diminished, however, in low income countries, that harbour the greatest burden of rotavirus attributed morbidity and mortality. Indirect effects of rotavirus vaccine (herd immunity and herd protection) could increase population level impact and improve vaccine cost effectiveness in such settings. While rotavirus vaccine indirect effects have been demonstrated in high and middle income countries, there are very little data from low income countries where force of infection, population structures and vaccine schedules differ. Targeted efforts to evaluate indirect effects of rotavirus vaccine in low income countries are required to understand the total impact of rotavirus vaccine on the global burden of rotavirus disease.     

Projected health and economic impact of rotavirus vaccination in GAVI-eligible countries: 2011-2030

Rotavirus is the leading cause of diarrheal disease in children under 5 years of age. It is responsible for more than 450,000 deaths each year, with more than 90% of these deaths occurring in low-resource countries eligible for support by the GAVI Alliance. Significant efforts made by the Alliance and its partners are providing countries with the opportunity to introduce rotavirus vaccines into their national immunization programs, to help prevent childhood illness and death. We projected the cost-effectiveness and health impact of rotavirus vaccines in GAVI-eligible countries, to assist decision makers in prioritizing resources to achieve the greatest health benefits for their populations. A decision-analytic model was used to project the health outcomes and direct costs of a birth cohort in the target population, with and without a rotavirus vaccine. Current data on disease burden, vaccine efficacy, immunization rates, and costs were used in the model. Vaccination in GAVI-eligible countries would prevent 2.46 million childhood deaths and 83 million disability-adjusted life years (DALYs) from 2011 to 2030, with annual reductions of 180,000 childhood deaths at peak vaccine uptake. The cost per DALY averted is $42 for all GAVI countries combined, over the entire period. Rotavirus vaccination would be considered very cost-effective for the entire cohort of GAVI countries, and in each country individually, as cost-effectiveness ratios are less than the gross domestic product (GDP) per capita. Vaccination is most cost-effective and has the greatest impact in regions with high rotavirus mortality. Rotavirus vaccination in GAVI-eligible countries is very cost-effective and is projected to substantially reduce childhood mortality in this population.     

The cost-effectiveness of pentavalent rotavirus vaccination in England and Wales

Rotavirus vaccines have shown great potential for reducing the disease burden of the major cause of severe childhood gastroenteritis. The decision regarding whether rotavirus vaccination will be introduced into the national immunization program is currently being reviewed. The conclusions of previous evaluations of rotavirus vaccination cost-effectiveness contradict each other. This is the first analysis to incorporate a dynamic transmission model to assess the cost-effectiveness of rotavirus vaccination in England and Wales. Most previously reported models do not include herd protection, and thus may underestimate the cost-effectiveness of vaccination against rotavirus. We incorporate a dynamic model of rotavirus transmission in England and Wales into a cost-effectiveness analysis to determine the probability that the pentavalent rotavirus vaccination will be cost-effective over a range of full-course vaccine prices. This novel approach allows the cost-effectiveness analysis to include a feasible level of herd protection provided by a vaccination program. Our base case model predicts that pentavalent rotavirus vaccination is likely to be cost-effective in England and Wales at £60 per course. In some scenarios the vaccination is predicted to be not only cost-effective but also cost-saving. These savings could be generated within ten years after vaccine introduction. Our budget impact analysis demonstrates that for the realistic base case scenarios, 58–96% of the cost outlay for vaccination will be recouped within the first four years of a program. Our results indicate that rotavirus vaccination would be beneficial to public health and could be economically sound. Since rotavirus vaccination is not presently on the immunization schedule for England and Wales but is currently under review, this study can inform policymakers of the cost-effectiveness and budget impact of implementing a mass rotavirus vaccine strategy.     

Impact of rotavirus vaccination on diarrheal hospitalizations in children younger than 5 years of age in a rural southern Mozambique

BackgroundRotavirus vaccine (Rotarix®) was introduced in Mozambique through its Expanded Program of Immunization in September 2015. We assessed the impact of rotavirus vaccination on childhood gastroenteritis-associated hospitalizations post-vaccine introduction in a high HIV prevalence rural setting of southern Mozambique.MethodsWe reviewed and compared the trend of hospitalizations (prevalence) and incidence rates of acute gastroenteritis (AGE), and rotavirus associated-diarrhea (laboratory confirmed rotavirus) in pre- (January 2008–August 2015) and post-rotavirus vaccine introduction periods (September 2015–December 2020), among children <5 years of age admitted to Manhiça District Hospital.ResultsFrom January 2008 to December 2020, rotavirus vaccination was found to contribute to the decline of the prevalence of AGE from 19% (95% CI: 18.14–20.44) prior to the vaccine introduction to 10% (95% CI: 8.89–11.48) in the post-introduction period, preventing 40% (95 % IE: 38–42) and 84% (95 % IE: 80–87) of the expected AGE and laboratory confirmed rotavirus cases, respectively, among infants. Similarly, the overall incidence of rotavirus was 11.8-fold lower in the post-vaccine introduction period (0.4/1000 child-years-at-risk [CYAR]; 95% CI: 0.3–0.6) compared with the pre-vaccination period (4.7/1000 CYAR; 95% CI: 4.2–5.1) with the highest reduction being observed among infants (16.8-fold lower from the 15.1/1000 CYAR in the pre-vaccine to 0.9/1000 CYAR in the post-vaccine eras).ConclusionsWe documented a significant reduction in all-cause diarrhea hospitalizations and rotavirus positivity after vaccine introduction demonstrating the beneficial impact of rotavirus vaccination in a highly vulnerable population.     

Economic Impact of a Rotavirus Vaccine in Brazil

The study was done to evaluate the cost-effectiveness of a national rotavirus vaccination programme in Brazilian children from the healthcare system perspective. A hypothetical annual birth-cohort was followed for a five-year period. Published and national administrative data were incorporated into a model to quantify the consequences of vaccination versus no vaccination. Main outcome measures included the reduction in disease burden, lives saved, and disability-adjusted life-years (DALYs) averted. A rotavirus vaccination programme in Brazil would prevent an estimated 1,804 deaths associated with gastroenteritis due to rotavirus, 91,127 hospitalizations, and 550,198 outpatient visits. Vaccination is likely to reduce 76% of the overall healthcare burden of rotavirus-associated gastroenteritis in Brazil. At a vaccine price of US$ 7-8 per dose, the cost-effectiveness ratio would be US$ 643 per DALY averted. Rotavirus vaccination can reduce the burden of gastroenteritis due to rotavirus at a reasonable cost-effectiveness ratio.Key words: Costs and cost analysis, Diarrhoea, Infantile, Gastroenteritis, Morbidity, Rotavirus, Rotavirus vaccines, Vaccination, Brazil     

Early impact of rotavirus vaccine in under 5 year old children hospitalized due to diarrhea,Swaziland

BackgroundSwaziland introduced rotavirus vaccine in the National Immunization Program, in May 2015, with the objective of reducing the burden of rotavirus diarrheal disease. We monitored the early impact of the vaccine in reducing rotavirus diarrhea.MethodsWe conducted sentinel rotavirus surveillance from January 2013 to December 2016 in children under five years of age admitted due to diarrhea attending Mbabane Government Referral Hospital in the Hhohho Region and Raleigh Fitkin Memorial Hospital in the Manzini Region. All cases had stool samples collected and tested for rotavirus antigen by enzyme immunoassay.ResultsBetween 2013 and 2016, 596 samples were collected and tested. Rotavirus positivity reduced from average of 50.8% (172/338) (in 2013–2014 (pre vaccine period)) to 29% (24/82) in 2016, post-vaccine introduction. The median age of children with rotavirus infection increased from average of 10 months in 2013–2014 to 13.7 months in 2016. The peak season for all-cause diarrhea and rotavirus-specific hospitalizations among children under five years of age was June–August in all years with a blunting of the peak season in 2016. Rotavirus positivity among children 0–11 months reduced from an average of 49% in 2013–2014 (116/236) to 33% (15/45) in 2016, a 33% reduction following rotavirus vaccine introduction.ConclusionThere has been a rapid reduction of all-cause diarrhea and rotavirus hospitalizations in Swaziland, particularly in young children and during the rotavirus season, after the introduction rotavirus vaccine. Continued surveillance is needed to monitor the long-term impact of rotavirus vaccine introduction.     

Predominance of unusual rotavirus G1P[6] strain in North India: An evidence from hospitalized children and adult diarrheal patients

Group A Rotavirus remains the leading cause of gastroenteritis in children and accounts for 0.2 million fatalities each year; out of which, approximately 47,100 deaths occur in India. In adults also, rotavirus is reported to be responsible for diarrhea severe enough to require hospitalizations. India has recently introduced rotavirus vaccine in the Universal Immunization Programme and Himachal Pradesh became the first Indian state to implement this project. This study is an attempt to provide the pre-vaccination data on rotavirus gastroenteritis burden and circulating genotypes in Himachal Pradesh, India. A total of 607 faecal specimens (247 children ≤ 5 years, 50 older children and 310 adults) from hospitalized diarrheal patients from Himachal Pradesh, India were screened for rotavirus using ELISA and RT-PCR. The positive samples were further G/P genotyped using semi-nested PCR. Rotavirus was detected in 25.2% and 28.3% of samples with ELISA and RT-PCR, respectively. In children, rotavirus frequency was significantly high with positivity in 49.0% cases whereas 14.0% adult samples have rotavirus in them. Genotyping of the positive samples revealed predominance of G1 (66.0%) and P[6] (66.7%) genotypes. The most common G and P combination was G1P[6] (62.8%) followed by G1P[8] (16.5%), G9P[6] (7.4%) and G12P[6] (5.0%). Molecular analysis reveals the belonging of P[6] strains in Lineage 1a. This pre-vaccination data on rotavirus prevalence and diversity would be helpful for assessing the affect of vaccination on the disease burden and its comparison with post-vaccination data of circulating genotypes would help in studying the effect on diversity of rotavirus strains possibly due to vaccine selection pressure.     

Impact of rotavirus vaccination on rotavirus hospitalizations in Taiwanese children

In 2006, two rotavirus vaccines were licensed in Taiwan but were not added to the national immunization schedule. National Health Insurance data from 2003 through 2017 were used to compare rotavirus-associated pediatric hospitalizations before and after vaccine introduction. Rotavirus hospitalization rates among children < 5 years of age significantly declined by 24% (95% confidence interval [CI] 23 – 25%) in post-vaccine compared to pre-vaccine rotavirus seasons. Rotavirus hospitalization rates declined by 42% (95% CI 39 – 44%) among infants < 12 months of age, and by 38% (95% CI 36 – 40%) among children 12 – 23 months of age. These findings suggest that, despite not being included in the national immunization schedule, rotavirus vaccines had a measurable impact on reducing rotavirus hospitalization burden among Taiwanese children.     

Association between mixed rotavirus vaccination types of infants and rotavirus acute gastroenteritis

IntroductionRotavirus remains the leading cause of severe diarrhea in children under 5 years worldwide. In the US, Rotarix^® (RV1) and RotaTeq^® (RV5), have been associated with reductions in and severity of rotavirus disease. Studies have evaluated the impact of RV1 or RV5 but little is known about the impact of incomplete or mixed vaccination upon vaccine effectiveness.MethodsCase control study to examine association of combined RV1 and RV5 and rotavirus acute gastroenteritis, factoring severity of diarrheal disease. Children born after March 1, 2009 with acute gastroenteritis from three pediatric hospitals in Atlanta, Georgia were approached for enrollment. Survey was administered, stool specimen was collected, and vaccination records were obtained.Results891 of 1127 children with acute gastroenteritis were enrolled. Stool specimens were collected from 708 for rotavirus testing; 215 stool samples tested positively for rotavirus. Children >12 months of age were more likely to have rotavirus. Children categorized with Vesikari score of >11 were almost twice as likely to be rotavirus positive. Prior rotavirus vaccination decreased the mean Vesikari score, p < 0.0001. Children with complete single type vaccination were protected against rotavirus (OR 0.21, 95% CI: 0.14–0.31, p < 0.0001).ConclusionComplete rotavirus vaccination with a single vaccine type resulted in protection against rotavirus diarrhea and decrease in severity of rotavirus gastroenteritis. Incomplete rotavirus vaccination either with a single vaccine or mixed vaccination types also provided some protection.     

A decade of rotavirus vaccination in Africa - Saving lives and changing the face of diarrhoeal diseases: Report of the 12th African Rotavirus Symposium

The African Rotavirus Network organised the 12^th African Rotavirus Symposium (ARS) from 30 July to 1 August 2019 in Johannesburg, South Africa. The symposium theme “A decade of rotavirus vaccination in Africa - Saving lives and changing the face of diarrhoeal diseases”, included sessions aimed at sharing ideas and expertise on prevention and control of diarrhoeal disease in Africa. Inter alia, the delegates reviewed global and regional epidemiological trends on rotavirus diarrhoea, progress and experiences on rotavirus vaccine introduction, including vaccine safety monitoring and impact in Africa, scientific advances in developing newer rotavirus vaccines, surveillance and research on other diarrhoeal pathogens, and providing an enabling environment for networking. Importantly, the 12^th ARS served to commemorate the 20^th anniversary of the African Rotavirus Network (AfrRN) coinciding with the 50th anniversary of the South African Medical Research Council.Four oral, live-attenuated rotavirus vaccines are currently prequalified by the WHO (Rotarix, RotaTeq, Rotavac and RotaSiil). African countries utilising rotavirus vaccines in routine national immunisation programmes are realising their effectiveness and impact on diarrhoeal disease morbidity. An ~40% reduction in hospitalisations of <5-year-olds with acute gastroenteritis following rotavirus vaccine introduction, was reported between 2006 and 2018 in 92,000 children from the WHO-coordinated African Rotavirus Surveillance Network (AfrRSN) comprising 33 Member States. This was corroborated by a meta-analysis of published data, sourced from January 2000 to August 2018 that reported substantial reductions in rotavirus hospitalisations in countries using rotavirus vaccines. However, it was highlighted that the transition of some countries from Gavi-eligibility and vaccine supply shortfalls present significant challenges to achieving the full impact of rotavirus immunization in Africa. The wide diversity of rotavirus genotypes continues in Africa, with variation observed both geographically and temporally. There is currently no evidence to suggest that the emergence of rotavirus strains not included in the current vaccines do escape vaccine-induced immunity.     

Cost-effectiveness of rotavirus vaccination in Mozambique

IntroductionRotavirus is one of the most common cause of severe gastroenteritis in children, with the largest mortality burden in low- and middle-income countries. To prevent rotavirus gastroenteritis, Mozambique introduced ROTARIX® vaccine in 2015, however, its cost-effectiveness has never been established in the country. In 2018, additional vaccines became available globally. This study estimates the cost-effectiveness of the recently introduced ROTARIX in Mozambique and compares the cost-effectiveness of ROTARIX®, ROTAVAC®, and ROTASIIL® to inform future use.MethodsWe used a decision-support model to calculate the potential cost-effectiveness of vaccination with ROTARIX compared to no vaccination over a five-year period (2016–2020) and to compare the cost-effectiveness of ROTARIX, ROTAVAC, and ROTASIIL to no vaccination and to each other over a ten-year period (2021–2030). The primary outcome was the incremental cost per disability-adjusted life-year (DALY) averted from a government perspective. We assessed uncertainty through sensitivity analyses.ResultsFrom 2016 to 2020, we estimate the vaccine program with ROTARIX cost US$12.3 million, prevented 4,628 deaths, and averted US$3.1 million in healthcare costs. The cost per DALY averted was US$70. From 2021 to 2030, we estimate all three vaccines could prevent 9,000 deaths and avert US$7.8 million in healthcare costs. With Global Alliance for Vaccines and Immunization (Gavi) support, ROTARIX would have the lowest vaccine program cost (US$31 million) and 98 % probability of being cost-effective at a willingness-to-pay threshold of 0.5x GDP per capita. Without Gavi support, ROTASIIL would have the lowest vaccine program cost (US$75.8 million) and 30 % probability of being cost-effective at the same threshold.ConclusionROTARIX vaccination had a substantial public health impact in Mozambique between 2016 and 2020. ROTARIX is currently estimated to be the most cost-effective product, but the choice of vaccine should be re-evaluated as more evidence emerges on the price, incremental delivery cost, wastage, and impact associated with each of the different rotavirus vaccines.     

Dynamic model of rotavirus transmission and the impact of rotavirus vaccination in Kyrgyzstan

New rotavirus vaccines show promise to reduce the burden of severe diarrhea among children in developing countries. We present an age-specific dynamic rotavirus model to assess the effect of rotavirus vaccination in Kyrgyzstan, a country in Central Asia that is eligible for funds from the GAVI Alliance. A routine rotavirus vaccination program at 95% coverage and 54% effectiveness against severe infection is estimated to lead to a 56% reduction in rotavirus-associated deaths and a 50% reduction in hospital admissions, while outpatient visits and homecare episodes would decrease by 52% compared to baseline levels after 5 years of intervention. A 10% reduction in vaccine efficacy due to incomplete 3-dose regimen is estimated to increase the numbers of severe cases by 6-8%. Herd immunity was found to account for 1% or less of averted cases of severe gastroenteritis, while an extra 7-8% of all rotavirus infections would be avoided due to reduced transmission. Conclusion: Rotavirus vaccines would reduce the burden of rotavirus disease substantially, but the results are sensitive to delay in age-appropriate vaccination.     

Early impact of rotavirus vaccination in children less than five years of age in Mozambique

BackgroundMozambique introduced rotavirus vaccine (Rotarix, GSK Biologicals) in the National Immunization Program in September 2015 with the objective of reducing the burden of total diarrheal disease and specifically severe rotavirus disease. This study aimed to evaluate the early impact of rotavirus vaccine in reducing all-cause diarrhea and rotavirus-specific hospitalizations.MethodsWe analysed stool specimens collected from children under five years old, between January 2014 and June 2017 within the National Surveillance for Acute Diarrhea. We compared annual changes in rotavirus positivity, median age of children hospitalized for rotavirus and the number of all-cause for diarrheal hospitalizations. Rotavirus detection was performed using enzyme immunoassay.ResultsDuring this period, 1296 samples were collected and analyzed. Rotavirus positivity before vaccine introduction was 40.2% (39/97) in 2014 and 38.3% (225/588) in 2015, then after vaccine introduction reduced to 12.2% and 13.5% in 2016 and 2017, respectively. The median age of children hospitalized for rotavirus was 9 and 11 months in 2014 and 2015 and 10 months in 2016 and 2017. Rotavirus hospitalizations exhibited a seasonal peak prior to vaccine introduction, between June and September in 2014 and 2015, coinciding with winter period in Mozambique. After vaccine introduction, the peak was delayed until August to December in 2016 and was substantially diminished. There was a reduction in all-cause acute diarrhea hospitalizations in children aged 0–11 months after vaccine introduction.ConclusionWe observed a reduction in rotavirus positivity and in the number of all-cause diarrhea hospitalizations after vaccine introduction. The data suggest rotavirus vaccine is having a positive impact on the control of rotavirus diarrheal disease in Mozambique.     

Effects of geographic and economic heterogeneity on rotavirus diarrhea burden and vaccination impact and cost-effectiveness in the Lao People’s Democratic Republic

Rotavirus enteritis is responsible for nearly 200,000 child deaths worldwide in 2015. Globally, many low- and middle-income countries have introduced rotavirus vaccine, resulting in documented reductions in hospitalizations and child mortality. We examined the potential impact and cost-effectiveness of introducing rotavirus vaccination in Lao People’s Democratic Republic using an Excel-based spreadsheet model. We estimated mortality risk factors, patterns of care seeking, and vaccination access to predict outcomes for regional, provincial, and socioeconomic subpopulations for one birth cohort through their first five years of life and life course in Disability-Adjusted Life Years estimates. Socioeconomic status was defined by categorizing households into regional wealth quintiles based on a national asset index. We modeled a two-dose ROTARIX vaccine under current Gavi pricing and efficacy estimates from Bangladesh and Vietnam. DPT1 and DPT2 coverages were used to estimate rotavirus vaccination coverage. Probabilistic sensitivity analysis was used to assess the impact of uncertainty on model parameters on predicted incremental cost-effectiveness ratios (ICERs), including scenarios of increases in vaccination coverage. Rotavirus vaccination would prevent 143 child deaths/year, or 28% of annual rotavirus burden. The estimated national level ICER for rotavirus vaccination was $140/DALY, with regional socioeconomic subpopulation estimates ranging from $72/DALY for the poorest in the Central region to $353/DALY for the richest in the North region, indicating high cost-effectiveness. Within regions, ICERs are most favorable for children in the poorer and poorest quintiles. However, the full benefits of rotavirus vaccination will only be realized by reducing disparities in vaccination coverage, access to treatment, and environmental health. Improving vaccination coverage to equitable levels alone would prevent 87 additional child deaths per year.