Recommendations for rotavirus vaccination: A worldwide perspective

Rotavirus in Calves and Its Zoonotic Importance

Rotavirus is a major pathogen responsible for diarrheal disease in calves, resulting in loss of productivity and economy of farmers. However, various facets of diarrheal disease caused by rotavirus in calves in the world are inadequately understood, considering that diarrheal disease caused by rotavirus is a vital health problem in calves that interrupts production benefits with reduced weight gain and increased mortality, and its potential for zoonotic spread. The pathological changes made by rotavirus are almost exclusively limited to the small intestine that leads to diarrhea. It is environmentally distributed worldwide and was extensively studied. Reassortment is one of the important mechanisms for generating genetic diversity of rotaviruses and eventually for viral evolution. So, the primary strategy is to reduce the burden of rotavirus infections by practicing early colostrum's feeding in newborn calves, using vaccine, and improving livestock management. Rotaviruses have a wide host range, infecting many animal species as well as humans. As it was found that certain animal rotavirus strains had antigenic similarities to some human strains, this may be an indication for an animal to play a role as a source of rotavirus infection in humans. Groups A to C have been shown to infect both humans and animals. The most commonly detected strains in both human and animals are G2, G3, G4, and G9, P [6]. Therefore, this review was made to get overview epidemiology status and zoonotic importance of bovine rotavirus.

Effectiveness of Rotarix ® vaccine in Africa in the first decade of progressive introduction, 2009-2019: systematic review and meta-analysis

Background: Randomized controlled trials of licensed oral rotavirus group A (RVA) vaccines, indicated lower efficacy in developing countries compared to developed countries. We investigated the pooled effectiveness of Rotarix ^® in Africa in 2019, a decade since progressive introduction began in 2009.

Methods: A systematic search was conducted in PubMed to identify studies that investigated the effectiveness of routine RVA vaccination in an African country between 2009 and 2019. A meta-analysis was undertaken to estimate pooled effectiveness of the full-dose versus partial-dose of Rotarix ^® (RV1) vaccine and in different age groups. Pooled odds ratios were estimated using random effects model and the risk of bias assessed using Newcastle-Ottawa scale. The quality of the evidence was assessed using GRADE.

Results: By December 2019, 39 (72%) countries in Africa had introduced RVA vaccination, of which 34 were using RV1. Thirteen eligible studies from eight countries were included in meta-analysis for vaccine effectiveness (VE) of RVA by vaccine dosage (full or partial) and age categories. Pooled RV1 VE against RVA associated hospitalizations was 44% (95% confidence interval (CI) 28-57%) for partial dose versus 58% (95% CI 50-65%) for full dose. VE was 61% (95% CI 50-69%), 55% (95% CI 32-71%), 56% (95% CI 43-67%), and 61% (95% CI 42-73%) for children aged <12 months, 12-23 months, <24 months and 12-59 months, respectively.

Conclusion: RV1 vaccine use has resulted in a significant reduction in severe diarrhoea in African children and its VE is close to the efficacy findings observed in clinical trials. RV1 VE point estimate was higher for children who received full dose than those who received partial dose, and its protection lasted beyond the first year of life.

Otieno G, Maia M, N. Agoti C. Effectiveness of Rotarix® vaccine in Africa in the first decade of progressive introduction, 2009-2019: systematic review and meta-analysis

Background: Randomized controlled trials of licensed oral rotavirus group A (RVA) vaccines, indicated lower efficacy in developing countries compared to developed countries. We investigated the pooled effectiveness of Rotarix® in Africa in 2019, a decade since progressive introduction began in 2009. Methods: A systematic search was conducted in PubMed to identify studies that investigated the effectiveness of routine RVA vaccination in an African country between 2009 and 2019. A meta-analysis was undertaken to estimate pooled effectiveness of the full-dose versus partial-dose of Rotarix® (RV1) vaccine and in different age groups. Pooled odds ratios were estimated using random effects model and the risk of bias assessed using Newcastle-Ottawa scale. The quality of the evidence was assessed using GRADE. Results: By December 2019, 39 (72%) countries in Africa had introduced RVA vaccination, of which 34 were using RV1. Thirteen eligible studies from eight countries were included in meta-analysis for vaccine effectiveness (VE) of RVA by vaccine dosage (full or partial) and age categories. Pooled RV1 VE against RVA associated hospitalizations was 44% (95% confidence interval (CI) 28-57%) for partial dose versus 58% (95% CI 50-65%) for full dose. VE was 61% (95% CI 50-69%), 55% (95% CI 32-71%), 56% (95% CI 43-67%), and 61% (95% CI 42-73%) for children aged <12 months, 12-23 months, <24 months and 12-59 months, respectively. Conclusion: RV1 vaccine use has resulted in a significant reduction in severe diarrhoea in African children and its VE is close to the efficacy findings observed in clinical trials. RV1 VE point estimate was higher for children who received full dose than those who received partial dose, and its protection lasted beyond the first year of life.

Impact of rotavirus vaccination on rotavirus and all-cause gastroenteritis in peri-urban Kenyan children

A monovalent rotavirus vaccine (RV1) was introduced into the National Immunization Program in Kenya in July 2014. We examined the impact of the vaccine on hospitalization for all-cause acute gastroenteritis (AGE) and rotavirus-specific AGE and strain distribution at a large referral hospital which serves a predominantly peri-urban population in Central Kenya. Data on rotavirus AGE and strain distribution were derived from ongoing hospital-based AGE surveillance. Hospital administrative data were used to compare trends in all-cause AGE. Pre-vaccine (July 2009-June 2014) and post-vaccine (July 2014-June 2016) periods were compared for changes in hospitalization for all-cause AGE and rotavirus AGE and strain distribution. Following the vaccine introduction, the proportion of children aged <5years hospitalized for rotavirus declined by 30% (95% CI: 19-45%) in the first year and 64% (95% CI: 49-77%) in the second year. Reductions in rotavirus positivity were most pronounced among the vaccine-eligible group (<12months) in the first year post-vaccination at 42% (95% CI: 28-56%). Greater reductions of 67% (95% CI: 51-79%) were seen in the second year in the 12-23months age group. Similarly, hospitalizations for all-cause AGE among children <5years of age decreased by 31% (95% CI: 24-40%) in the first year and 58% (95% CI: 49-67%) in the second year of vaccine introduction. Seasonal peaks of rotavirus and all-cause AGE were reduced substantially. There was an increased detection of G2P[4], G3P[6] and G3P[8], which coincided temporally with the timing of the vaccine introduction. Thus, introducing the rotavirus vaccine into the routine immunization program in Kenya has resulted in a notable decline in rotavirus and all-cause AGE hospitalizations in Central Kenya. This provides early evidence for public health policy makers in Kenya to support the sustained use of the rotavirus vaccine in routine immunizations.

Variation in rotavirus vaccine coverage by sub-counties in Kenya

Rotavirus gastroenteritis is an important cause of childhood morbidity and mortality in Kenya. In July 2014, Kenya introduced the rotavirus vaccine into her national immunization program. Although immunization coverage is crucial in assessing the real-world impact of this vaccine, variability in the vaccine coverage across the country is likely to occur. In view of this, we estimated the extent of coverage for the rotavirus vaccine at two socio-economically different sub-counties using the administrative data. The findings indicate disparities in vaccine coverage and access between the sub-counties and, thus, underscore the need to strengthen immunization systems to facilitate timely, accessible, and equitable vaccine delivery across the country. Both sub-counties recorded high vaccine dropout, suggestive of poor utilization of the vaccine. In this regard, increased social mobilization is needed to encourage vaccine compliance and to enhance tracking of vaccine defaulters. While efforts to improve the accuracy of the administrative coverage estimates are crucial, vaccination coverage surveys will be needed to verify the administrative coverage data and help identify specific factors relating to rotavirus vaccine coverage in the country.

Therapeutics Insight with Inclusive Immunopharmacology Explication of Human Rotavirus A for the Treatment of Diarrhea

Rotavirus is the most common cause of severe infant and childhood diarrhea worldwide, and the morbidity and mortality rate is going to be outnumbered in developing countries like Bangladesh. To mitigate this substantial burden of disease, new therapeutics such as vaccine and drug are swiftly required against rotavirus. The present therapeutics insight study was performed with comprehensive immunoinformatics and pharmacoinformatics approach. T and B-cell epitopes were assessed in the conserved region of outer capsid protein VP4 among the highly reviewed strains from different countries including Bangladesh. The results suggest that epitope SU1 (TLKNLNDNY) could be an ideal candidate among the predicted five epitopes for both T and B-cell epitopes for the development of universal vaccine against rotavirus. This research also suggests five novel drug compounds from medicinal plant Rhizophora mucronata Lamk. for better therapeutics strategies against rotavirus diarrhea based on 3D structure building, pharmacophore, ADMET, and QSAR properties. The exact mode of action between drug compounds and target protein VP4 were revealed by molecular docking analysis. Drug likeness and oral bioavailability further confirmed the effectiveness of the proposed drugs against rotavirus diarrhea. This study might be implemented for experimental validation to facilitate the novel vaccine and drug design.

Knowledge and attitudes towards rotavirus diarrhea and the vaccine amongst healthcare providers in Yogyakarta Indonesia

Background

Rotavirus has been identified as the most common pathogen associated with severe diarrhoea. Two effective vaccines against the pathogen have been licensed. However, many countries including Indonesia have yet to introduce the vaccine into their national immunisation programs. This study aimed to examine the attitudes of healthcare providers (HCPs) and other health stakeholders towards the pathogen and the vaccine.

Methods

Semi-structured in-depth interviews were undertaken in two districts of Yogyakarta Province, Indonesia with nurses, midwives, primary care providers, pediatricians and other health stakeholders. Thematic analysis was undertaken.

Results

Fourteen interviews were conducted between August and October 2013. We identified that while participants do not consider diarrhea to be an important problem in Indonesia, they do acknowledge that it can be serious if not properly treated. While the majority had some level of knowledge about rotavirus, not all participants knew that a vaccine was available. There were mixed feelings towards the need for the vaccine. Some felt that the vaccine is not ranked as a priority as it is not listed on the national program. However, others agreed there is a rationale for its use in Indonesia. The cost of the vaccine (when sold in the private sector) was perceived to be the primary barrier impacting on its use.

Conclusions

The high cost and the low priority given to this vaccine by the public health authorities are the biggest obstacles impacting on the acceptance of this vaccine in Indonesia. HCPs need to be reminded of the burden of disease associated with rotavirus. In addition, reminding providers about the costs associated with treating severe cases versus the costs associated with prevention may assist with improving the acceptance of HCPs towards the vaccine. Promotion campaigns need to target the range of HCPs involved in the provision of care to infants and pregnant women.

Recommendations for rotavirus vaccine

Rotavirus infection has been the leading cause of gastroenteritis among children in Taiwan. Studies have shown that 40% of hospitalization for acute gastroenteritis can be prevented through the use of vaccines, including a live, attenuated monovalent rotavirus vaccine and a pentavalent, human-bovine reassortant rotavirus vaccine. In 2009, the World Health Organization suggested that rotavirus vaccine should be included in all national immunization programs. This review summarizes issues and recommendations discussed during an expert meeting in Taiwan. The recommendations included: (1) rotavirus vaccine should be offered to all healthy infants (including those without contraindications, such as immunodeficiency) at an appropriate age; (2) either monovalent or pentavalent vaccine can be administered concurrently with routine injected vaccines; (3) the administration of rotavirus vaccine must be administered at least 2 weeks prior to oral polio vaccination; (4) the first vaccine dose for infants should be administered between age 6 weeks and age 14 weeks 6 days and the course should be completed by age 8 months 0 day; (5) pentavalent vaccines can be administered at 2 months, 4 months, and 6 months while monovalent vaccines can be taken at 2 months and 4 months; (6) a combined use of monovalent and pentavalent vaccine is justified only when the previous dose is unavailable or unknown; and (7) rotavirus vaccines may be given to premature infants, human immunodeficiency virus infected infants and infants who have received or are going to receive blood products.

Rotavirus vaccination in central Europe

Each year, rotavirus (RV) infection is the leading cause of acute gastroenteritis requiring hospitalisation and of nosocomially transmitted diseases in children younger than 5 years across Central European Vaccination Awareness Group (CEVAG) countries; however, inadequate surveillance systems and lack of routine RV testing still exist in most CEVAG countries, making it difficult to accurately assess the present burden of acute RV gastroenteritis in the younger population. Furthermore, routine immunisation of infants with RV vaccines has not been implemented, and no official and uniform recommendations exist in most of the countries in these territories. The present study provides CEVAG country-specific estimates of the disease burden of RV gastroenteritis among the youngest population and presents evidence-based advice on the use of RV vaccines in the region, while providing a framework for vaccination at the national level.

The unpredictable diversity of co-circulating rotavirus types in Europe and the possible impact of universal mass vaccination programmes on rotavirus genotype incidence

This article reviews the incidence of group A rotavirus (RV) types isolated from children with acute gastroenteritis (AGE) in European countries during the last 5-10 years, with the aim of establishing an overview of RV diversity before the introduction of universal mass vaccination (UMV) programmes against RV disease in most European countries. Consistent with findings from previous surveys, a high degree of diversity of co-circulating RV types exists in different locations of Europe, and over different RV seasons. Whilst RV UMV can potentially change the diversity of co-circulating genotypes, there are at present insufficient data for Europe to come to firm conclusions. Even in countries outside Europe, with several years of RV surveillance following the introduction of RV UMV (Brazil, Australia, USA), it is not clear whether changes observed in the diversity of particular RV types are due to natural fluctuations or immunological pressure exerted by RV UMVs. Consequently, it will be very difficult for European countries that have RV UMVs to conclude whether incidence changes of RV types in children with AGE are driven by immune pressures from vaccination or simply reflect natural temporal and spatial fluctuations. Whilst the monitoring of co-circulating RV strains should be continued, it should be acknowledged that the licensed monovalent and pentavalent RV vaccines are similarly effective in developed countries and that levels of RV type-specific neutralising antibodies after RV vaccination are only partially correlated with the degree of protection achieved; therefore, the significance of RV diversity for RV vaccination may be less important than is often assumed.

Effectiveness and safety of Saccharomyces boulardii for acute infectious diarrhea

INTRODUCTION

Acute diarrhea continues to be a leading cause of morbidity, hospitalization and mortality worldwide and probiotics have been proposed as a complementary therapy in the treatment of acute diarrhea. Regarding the treatment of acute diarrhea, a few probiotics including Saccharomyces boulardii seem to be promising therapeutic agents.

AREAS COVERED

We performed a systematic review and meta-analysis regarding the use of S. boulardii in the treatment of acute infectious diarrhea with relevant studies that searched with the PubMed, Embase, Scopus, Google Scholar, the Cochrane Controlled Trials Library, and the Cochrane Database of Systematic Reviews through October 2011. This review describes the effects of S. boulardii on the duration of diarrhea, the risk of diarrhea during the treatment (especially at the third day) and duration of hospitalization in patients with acute infectious diarrhea. This review also focused on the potential effects of S. boulardii for acute infectious diarrhea due to different etiological causes.

EXPERT OPINION

S. boulardii significantly reduced the duration of diarrhea approximately 24 h and that of hospitalization approximately 20 h. S. boulardii shortened the initial phase of watery stools; mean number of stools started to decrease at day 2; moreover, a significant reduction was reported at days 3 and 4. This systematic review and meta-analysis of the efficacy of S. boulardii in the treatment of acute infectious diarrhea show that there is strong evidence that this probiotic has a clinically significant benefit, whatever the cause, including in developing countries. Therefore, with S. boulardii, the shortened duration of diarrhea and the reduction in hospital stay result in social and economic benefits.