Does Rotavirus Vaccination Affect Longer-Term Intussusception Risk in US Infants?

Impact of vaccination with different types of rotavirus vaccines on the incidence of intussusception: a randomized controlled meta-analysis

Background

Intussusception is a prevalent pediatric issue causing acute abdominal pain, with potential links to rotavirus vaccines. The variety of these vaccines has grown in recent years. This meta-analysis study aims to evaluate the impact of various rotavirus vaccines on intussusception incidence.

Methods

We executed a thorough search across databases like PubMed, Cochrane Library, Embase, and Web of Science, leading to the selection of 15 credible randomized controlled trials (RCTs) that encompass various types of rotavirus vaccines. From each study, we extracted essential details such as vaccine types and intussusception occurrences. We assessed the risk of bias using the Cochrane Collaboration's tool, conducted statistical analysis with R (version 4.2.3), determined relative risk (RR) using a random effects model, and performed a subgroup analysis for vaccines of differing brands and types.

Results

We included 15 randomized controlled studies from various countries. While intussusception incidence differed between vaccinated and control groups, this difference was not statistically significant. The overall risk ratio (RR), calculated using a random effects model, was 0.81, with a 95% confidence interval of [0.53, 1.23]. This crossing 1 shows that vaccination didn't notably change disease risk. Additionally, the 0% group heterogeneity suggests consistency across studies, strengthening our conclusions. Subgroup analysis for different vaccine brands and types (RV1 (Rotarix, Rotavac, RV3-BB), RV3 (LLR3), RV5 (RotasiiL, RotaTeq), and RV6) showed no significant variation in intussusception incidence. Despite variations in RR among subgroups, these differences were not statistically significant (P > 0.05).

Conclusions

Our study indicates that rotavirus vaccination does not significantly increase the incidence of intussusception. Despite varying impacts across different vaccine brands and types, these variations are insignificant. Given the substantial benefits outweighing the risks, promoting the use of newly developed rotavirus vaccines remains highly valuable.

Systematic Review Registration

www.crd.york.ac.uk/prospero/, Identifier CRD42023425279.

The Value of Rotavirus Vaccination in Europe: A Call for Action

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has pushed many healthcare systems into crisis. High vaccine coverage amongst children reduces emergency room presentations, hospital admissions and deaths due to vaccine-preventable diseases, freeing up healthcare resources including polymerase chain reaction testing for patients with SARS-CoV-2. In Europe, rotavirus gastroenteritis leads to 75,000-150,000 hospitalisations and up to 600,000 medical encounters annually. Nevertheless, in 2022, only 18 countries in Europe (out of 38) have a publicly funded routine universal mass immunisation programme against rotavirus gastroenteritis. Evidence available in the last few years re-emphasises that rotavirus vaccines currently available in Europe are highly effective, preventing up to 96% of rotavirus-related hospitalisations in children less than 1 year of age (potentially 72,000-144,000 hospitalisations Europe-wide). Long-term surveillance indicates that rotavirus vaccination does not result in an overall increase in intussusception. On the contrary, increasing evidence suggests an overall reduction in intussusception in the first 12 months of life when early, high rotavirus vaccine coverage is achieved. Prevention of rotavirus gastroenteritis has marked positive impacts on parental wages and government tax revenue, with benefits extending across the whole economy. In the SARS-CoV-2 pandemic setting there is a new imperative to achieve high levels of paediatric vaccination against vaccine-preventable diseases, including rotavirus gastroenteritis. The introduction of rotavirus universal mass vaccination can be expected to reduce the number of preventable illnesses, hospitalisations and deaths caused by rotavirus gastroenteritis. Reducing vaccine-preventable diseases is particularly urgent at this time when healthcare systems are preoccupied and overwhelmed with SARS-CoV-2. Graphical abstract available for this article.

Established and new rotavirus vaccines: a comprehensive review for healthcare professionals

Robust scientific evidence related to two rotavirus (RV) vaccines available worldwide demonstrates their significant impact on RV disease burden. Improving RV vaccination coverage may result in better RV disease control. To make RV vaccination accessible to all eligible children worldwide and improve vaccine effectiveness in high-mortality settings, research into new RV vaccines continues. Although current and in-development RV vaccines differ in vaccine design, their common goal is the reduction of RV disease risk in children <5 years old for whom disease burden is the most significant. Given the range of RV vaccines available, informed decision-making is essential regarding the choice of vaccine for immunization. This review aims to describe the landscape of current and new RV vaccines, providing context for the assessment of their similarities and differences. As data for new vaccines are limited, future investigations will be required to evaluate their performance/added value in a real-world setting.

Review of Over 15 Years Postmarketing Safety Surveillance Spontaneous Data for the Human Rotavirus Vaccine (Rotarix) on Intussusception

Introduction

Rotavirus (RV) is the most common cause of acute gastroenteritis in children <5 years of age worldwide, and vaccination reduces the disease burden. Evidence from postmarketing surveillance studies suggested an increased risk of intussusception (IS) in infants post-RV vaccination. An overall positive benefit–risk balance for the human RV vaccine (HRV) Rotarix (GlaxoSmithKline [GSK], Belgium) has been established and recent findings indicate an indirect effect of reduced IS over the long term.

Objective

The aim of this study was to discuss spontaneous data from the GSK worldwide safety database on IS post-Rotarix administration.

Methods

The database was reviewed for all spontaneous IS cases from 2004 to 2020. Additionally, an observed versus expected (O/E) analysis was done for adverse events attributed to IS. Data were reviewed as overall worldwide and stratified by region (Europe/USA/Japan) and dose.

Results

A male predominance of IS patients was observed, consistent with earlier reports. The most frequently reported events in confirmed IS cases (Brighton Collaboration Working Group [BCWG] level 1) with time to onset ≤ 30 days post-vaccination were vomiting (55.8%), haematochezia (47.2%), and crying (21.1%). The observations from the IS spontaneous cases review and results of the O/E analysis are consistent with the known IS safety profile of RV vaccines: a transient increased incidence of IS post-vaccination (primarily in Europe/Japan/worldwide), mostly within 7 days postdose 1.

Conclusion

Since the outcomes of early IS management are favourable over delayed management, healthcare professionals should inform parents about the importance of seeking immediate medical advice in case of unusual behaviour of the vaccinated infant. GSK continues to monitor the IS risk post-Rotarix administration through routine pharmacovigilance activities.

Graphic abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s40264-021-01141-4.

Rotavirus (RV) is the most common cause of acute gastroenteritis and a major cause of death in young children worldwide. Vaccination has been instrumental in reducing the impact of RV disease. Real-world evidence suggests an increased risk of intussusception (an infrequent type of bowel obstruction) in infants following RV vaccination. We reviewed IS cases reported spontaneously worldwide in children following a two-dose vaccination with the human RV vaccine (Rotarix, GlaxoSmithKline [GSK]) since its launch in 2004. We observed that (1) IS occurred more frequently 7 days after the first dose and, to a lesser extent, after the second dose; (2) boys were more frequently affected than girls (56.3%); (3) of 862 confirmed reported cases, 557 required hospitalisation; and (4) surgical intervention was required for 294 of 557 hospitalised cases. We used statistical analysis to assess whether the number of cases observed would be higher or lower than the natural occurrence of IS (irrespective of vaccination). These results were in line with the known RV vaccine safety profile. It is important to constantly monitor the real-world safety profile of RV vaccines in the postmarketing setting. Since the outcomes of early management of IS are favourable compared with delayed management, healthcare professionals should inform parents to seek immediate medical advice if they observe unusual behaviour in their vaccinated child. In conclusion, our analyses on data of a large patient pool for this rare event reinforce the favourable safety profile of human RV vaccine and the benefits of vaccination in young children.

Rotavirus research: 2014-2020

Rotaviruses are major causes of acute gastroenteritis in infants and young children worldwide and also cause disease in the young of many other mammalian and of avian species. During the recent 5-6 years rotavirus research has benefitted in a major way from the establishment of plasmid only-based reverse genetics systems, the creation of human and other mammalian intestinal enteroids, and from the wide application of structural biology (cryo-electron microscopy, cryo-EM tomography) and complementary biophysical approaches. All of these have permitted to gain new insights into structure-function relationships of rotaviruses and their interactions with the host. This review follows different stages of the viral replication cycle and summarizes highlights of structure-function studies of rotavirus-encoded proteins (both structural and non-structural), molecular mechanisms of viral replication including involvement of cellular proteins and lipids, the spectrum of viral genomic and antigenic diversity, progress in understanding of innate and acquired immune responses, and further developments of prevention of rotavirus-associated disease.

Safety of vaccines used for routine immunization in the United States: An updated systematic review and meta-analysis

BACKGROUND

Understanding the safety of vaccines is critical to inform decisions about vaccination. Our objective was to conduct a systematic review of the safety of vaccines recommended for children, adults, and pregnant women in the United States.

METHODS

We searched the literature in November 2020 to update a 2014 Agency for Healthcare Research and Quality review by integrating newly available data. Studies of vaccines that used a comparator and reported the presence or absence of key adverse events were eligible. Adhering to Evidence-based Practice Center methodology, we assessed the strength of evidence (SoE) for all evidence statements. The systematic review is registered in PROSPERO (CRD42020180089).

RESULTS

Of 56,603 reviewed citations, 338 studies reported in 518 publications met inclusion criteria. For children, SoE was high for no increased risk of autism following measles, mumps, and rubella (MMR) vaccine. SoE was high for increased risk of febrile seizures with MMR. There was no evidence of increased risk of  intussusception with rotavirus vaccine at the latest follow-up (moderate SoE), nor of diabetes (high SoE). There was no evidence of increased risk or insufficient evidence for key adverse events for newer vaccines such as 9-valent human papillomavirus and meningococcal B vaccines. For adults, there was no evidence of increased risk (varied SoE) or insufficient evidence for key adverse events for the new adjuvanted inactivated influenza vaccine and recombinant adjuvanted zoster vaccine. We found no evidence of increased risk (varied SoE) for key adverse events among pregnant women following tetanus, diphtheria, and acellular pertussis vaccine, including stillbirth (moderate SoE).

CONCLUSIONS

Across a large body of research we found few associations of vaccines and serious key adverse events; however, rare events are challenging to study. Any adverse events should be weighed against the protective benefits that vaccines provide.

Novel vaccine safety issues and areas that would benefit from further research

Vaccine licensure requires a very high safety standard and vaccines routinely used are very safe. Vaccine safety monitoring prelicensure and postlicensure enables continual assessment to ensure the benefits outweigh the risks and, when safety problems arise, they are quickly identified, characterised and further problems prevented when possible. We review five vaccine safety case studies: (1) dengue vaccine and enhanced dengue disease, (2) pandemic influenza vaccine and narcolepsy, (3) rotavirus vaccine and intussusception, (4) human papillomavirus vaccine and postural orthostatic tachycardia syndrome and complex regional pain syndrome, and (5) RTS,S/adjuvant system 01 malaria vaccine and meningitis, cerebral malaria, female mortality and rebound severe malaria. These case studies were selected because they are recent and varied in the vaccine safety challenges they elucidate. Bringing these case studies together, we develop lessons learned that can be useful for addressing some of the potential safety issues that will inevitably arise with new vaccines.

Fifteen years of experience with the oral live-attenuated human rotavirus vaccine: reflections on lessons learned

INTRODUCTION

Rotavirus (RV) disease remains a prominent cause of disease burden in children <5 years of age worldwide. However, implementation of RV vaccination has led to significant reductions in RV mortality, compared to the pre-vaccination era. This review presents 15 years of real-world experience with the oral live-attenuated human RV vaccine (HRV; Rotarix). HRV is currently introduced in ≥80 national immunization programs (NIPs), as 2 doses starting from 6 weeks of age.

AREAS COVERED

The clinical development of HRV and post-marketing experience indicating the impact of HRV vaccination on RV disease was reviewed.

EXPERT OPINION

In clinical trials, HRV displayed an acceptable safety profile and efficacy against RV-gastroenteritis, providing broad protection against heterotypic RV strains by reducing the consequences of severe RV disease in infants. Real-world evidence shows substantial, rapid reduction in the number of RV infections and associated hospitalizations following introduction of HRV in NIPs, regardless of economic setting. Indirect effects against RV disease are also observed, such as herd protection, decrease in nosocomial infections incidence, and a reduction of disease-related societal/healthcare costs. However, not all countries have implemented RV vaccination. Coverage remains suboptimal and should be improved to maximize the benefits of RV vaccination.

Rotavirus vaccination and intussusception: a paradigm shift?

Rotavirus (RV) is one of the leading causes of severe childhood gastroenteritis in children <5 years of age. Several countries have successfully implemented vaccination against RV disease; however, hesitancy to include RV vaccination in the national immunization program exists and relates, among other reasons, to the results of international post-licensure studies of RV vaccines that established an increased risk of intussusception (IS) in infants following immunization. IS is one of the major causes of bowel obstruction in infants between 4 and 10 months of age. Some studies have investigated the etiology of IS, including the role of natural RV infection and available evidence suggests that RV disease may be an independent risk factor for IS. In this regard, the benefit-risk profile of RV vaccination, which is recognized as positive, could potentially turn out to be even more favorable in preventing IS cases triggered by RV disease. However, further research is prompted to quantify the IS risk attributable to RV disease.

Retrospective multicenter matched case-control study on the risk factors for intussusception in infants less than 1 year of age with a special focus on rotavirus vaccines - the German Intussusception Study

Studies associate rotavirus vaccination with intussusception. In Germany, a retrospective multicenter matched case-control study was performed to identify risk factors for intussusception with a special focus on rotavirus vaccines. Children with place of birth and residence in Germany who had been treated for intussusception from 2010 to 2014 and who had been less than 1 year old at the time of intussusception were recruited. Case report forms were independently validated by two pediatricians according to the criteria of intussusception defined by the Brighton Collaboration (BC). Cases with the highest diagnostic certainty (level 1) were matched with population-based controls by age, gender, federal state, and place of residence. Information on vaccine exposures originated from vaccination certificates. One hundred and sixteen cases were matched with 272 controls. A significantly increased adjusted odds ratio (aOR) for intussusception (5.74, 95% CI: 1.51-21.79) was detected in individuals immunized with rotavirus vaccine dose 1 prior to symptom onset as compared to non-exposed individuals. Age at the start of the rotavirus immunization series did not modify the risk of intussusception. The odds for intussusception were not increased postdose 2 and 3 as well as any dose. One further risk factor for intussusception, family history of intussusception (aOR 3.26, 95% CI 1.09 - 9.77) was identified. Breastfeeding was found to have a protective effect (aOR 0.54, 95% CI 0.33 - 0.88). Rotavirus vaccine dose 1 was associated with a 5.7-fold increased risk to develop intussusception regardless of age at immunization whereas the overall risk for intussusception in the first year of life was not increased.