Decline in diarrhea mortality and admissions after routine childhood rotavirus immunization in Brazil: a time-series analysis

Long-term impact of rotavirus vaccination on all-cause and rotavirus-specific gastroenteritis and strain distribution in Central Kenya: An 11-year interrupted time-series analysis

BACKGROUND

Kenya introduced a monovalent rotavirus vaccine administered orally at 6 and 10 weeks of age into her National Immunization Program in July 2014. The study evaluated the long-term impact of the vaccine on hospitalization for all-cause and rotavirus-specific acute gastroenteritis (AGE) and strain epidemiology in Kenya.

METHODS

Data on all-cause and rotavirus-specific AGE and strain distribution were derived from an eleven-year hospital-based surveillance of AGE among children aged <5 years at Kiambu County Teaching and Referral Hospital (KCTRH) in Central Kenya between 2009 and 2020. Fecal samples were screened for group A rotavirus using ELISA and genotyped using multiplex semi-nested RT-PCR. Trends in all-cause and rotavirus-related AGE and strain distribution were compared between the pre-vaccine (July 2009-June 2014), early post-vaccine (July 2014-June 2016) and late post-vaccine (February 2019-October 2020) periods.

RESULTS

Rotavirus-specific AGE was detected at 27.5% (429/1546, 95% CI: 25.5-30.1%) in the pre-vaccine period; 13.8% (91/658, 95% CI: 11.3-16.6%) in the early post-vaccine period (July 2014-June 2016); and 12.0% (229/1916, 95% CI: 10.6-13.5%) in the late post-vaccine period (February 2019-October 2020). This amounted to a decline of 49.8% (95% CI: 34.6%-63.7%) in rotavirus-specific AGE in the early post-vaccine period and 53.4% (95% CI: 41.5-70.3%) in the late post-vaccine period when compared to the pre-vaccine period. All-cause AGE hospitalizations declined by 40.2% (95% CI: 30.8%-50.2%) and 75.3% (95% CI: 65.9-83.1%) in the early post-vaccine and late post-vaccine periods, respectively, when compared to the pre-vaccine period. G3P [8] was the predominant strain in the late post-vaccine period, replacing G1P[8] which had predominated in the pre-vaccine and early post-vaccine periods. Additionally, we detected considerable proportions of uncommon strains G3P[6] (4.8%) and G12P[6] (3.5%) in the post-vaccine era.

CONCLUSION

Rotavirus vaccination has resulted in a significant decline in all-cause and rotavirus-specific AGE, and thus, provides strong evidence for public health policy makers in Kenya to support the sustained use of the rotavirus vaccine in routine immunization. However, the shift in strain dominance and age distribution of rotavirus AGE in the post-vaccine era underscores the need for continued surveillance to assess any possible vaccine-induced selective pressure that could diminish the vaccine effectiveness over time.

T cell epitope based vaccine design while targeting outer capsid proteins of rotavirus strains infecting neonates: an immunoinformatics approach

Gastrointestinal diarrhea is majorly caused by the rotavirus (RV) in the children who generally are under the age group of 5 years. WHO estimates that ∼95% of the children contract RV infection, by this age. The disease is highly contagious; notably in many cases, it is proven fatal with high mortality rates especially in the developing countries. In India alone, an estimated 145,000 yearly deaths occurs due to RV related gastrointestinal diarrhea. WHO pre-qualified vaccines that are available for RV are all live attenuated vaccines with modest efficacy range between 40 and 60%. Further, the risk of intussusceptions has been reported in some children on RV vaccination. Thus, in a quest to develop alternative candidate to overcome challenges associated with these oral vaccines, we chose immunoinformatics approach to design a multi-epitope vaccine (MEV) while targeting the outer capsid viral proteinsVP4 and VP7 of the neonatal strains of rotavirus. Interestingly, ten epitopes, that is, six CD8+T-cells and four CD4+T-cell epitopes were identified which were predicted to be antigenic, non-allergic, non-toxic and stable. These epitopes were then linked to adjuvants, linkers, and PADRE sequences to create a multi-epitope vaccine for RV. The in silico designed RV-MEV and human TLR5 complex displayed stable interactions during molecular dynamics simulations. Further, the immune simulation studies of RV-MEV corroborated that the vaccine candidate emerges as a promising immunogen. Future investigations while performing in vitro and in vivo analyses with designed RV-MEV construct are highly desirable to warrant the potential of this vaccine candidate in protective immunity against different strains of RVs infecting neonates.Communicated by Ramaswamy H. Sarma.

Immunogenicity of RV1 and RV5 vaccines administered in standard and interchangeable mixed schedules: a randomized, double-blind, non-inferiority clinical trial in Mexican infants

Introduction

Rotavirus-associated diarrheal diseases significantly burden healthcare systems, particularly affecting infants under five years. Both Rotarix™ (RV1) and RotaTeq™ (RV5) vaccines have been effective but have distinct application schedules and limited interchangeability data. This study aims to provide evidence on the immunogenicity, reactogenicity, and safety of mixed RV1-RV5 schedules compared to their standard counterparts.

Methods

This randomized, double-blind study evaluated the non-inferiority in terms of immunogenicity of mixed rotavirus vaccine schedules compared to standard RV1 and RV5 schedules in a cohort of 1,498 healthy infants aged 6 to 10 weeks. Participants were randomly assigned to one of seven groups receiving various combinations of RV1, and RV5. Standard RV1 and RV5 schedules served as controls of immunogenicity, reactogenicity, and safety analysis. IgA antibody levels were measured from blood samples collected before the first dose and one month after the third dose. Non-inferiority was concluded if the reduction in seroresponse rate in the mixed schemes, compared to the standard highest responding scheme, did not exceed the non-inferiority margin of -0.10. Reactogenicity traits and adverse events were monitored for 30 days after each vaccination and analyzed on the entire cohort.

Results

Out of the initial cohort, 1,365 infants completed the study. Immunogenicity analysis included 1,014 infants, considering IgA antibody titers ≥20 U/mL as seropositive. Mixed vaccine schedules demonstrated non-inferiority to standard schedules, with no significant differences in immunogenic response. Safety profiles were comparable across all groups, with no increased incidence of serious adverse events or intussusception.

Conclusion

The study confirms that mixed rotavirus vaccine schedules are non-inferior to standard RV1 and RV5 regimens in terms of immunogenicity and safety. This finding supports the flexibility of rotavirus vaccination strategies, particularly in contexts of vaccine shortage or logistic constraints. These results contribute to the global effort to optimize rotavirus vaccination programs for broader and more effective pediatric coverage.Clinical trial registration: ClinicalTrials.gov, NCT02193061.

Rotavirus in developing countries: molecular diversity, epidemiological insights, and strategies for effective vaccination

Rotavirus (RV) causes the loss of numerous children's lives worldwide each year, and this burden is particularly heavy in low- and lower-middle-income countries where access to healthcare is limited. RV epidemiology exhibits a diverse range of genotypes, which can vary in prevalence and impact across different regions. The human genotypes that are most commonly recognized are G1P[8], G2P[4], G3P[8], G4P[8], G8P[8], G9P[8], and G12P[8]. The diversity of rotavirus genotypes presents a challenge in understanding its global distribution and developing effective vaccines. Oral, live-attenuated rotavirus vaccines have undergone evaluation in various contexts, encompassing both low-income and high-income populations, demonstrating their safety and effectiveness. Rotavirus vaccines have been introduced and implemented in over 120 countries, offering an opportunity to assess their effectiveness in diverse settings. However, these vaccines were less effective in areas with more rotavirus-related deaths and lower economic status compared to wealthier regions with fewer rotavirus-related deaths. Despite their lower efficacy, rotavirus vaccines significantly decrease the occurrence of diarrheal diseases and related mortality. They also prove to be cost-effective in regions with a high burden of such diseases. Regularly evaluating the impact, influence, and cost-effectiveness of rotavirus vaccines, especially the newly approved ones for worldwide use, is essential for deciding if these vaccines should be introduced in countries. This is especially important in places with limited resources to determine if a switch to a different vaccine is necessary. Future research in rotavirus epidemiology should focus on a comprehensive understanding of genotype diversity and its implications for vaccine effectiveness. It is crucial to monitor shifts in genotype prevalence and their association with disease severity, especially in high-risk populations. Policymakers should invest in robust surveillance systems to monitor rotavirus genotypes. This data can guide vaccine development and public health interventions. International collaboration and data sharing are vital to understand genotype diversity on a global scale and facilitate the development of more effective vaccines.

Evidence of waste management impacting severe diarrhea prevalence more than WASH: An exhaustive analysis with Brazilian municipal-level data

Adequate housing protects from diarrhea, which is a substantial health concern in low- and middle-income countries. The purpose of this study was to quantify the relationship between severe diarrhea and housing features at the municipal level to help in public health planning. Regression analyses were performed on annual (2000-2012) datasets on Brazilian municipalities (5570) in six household feature categories (e.g., waste management) and four severe diarrhea outcomes (e.g., diarrhea deaths of under-5 children). Household data were not available elsewhere of this magnitude and granularity, highlighting the scientific value-add of this study. Municipalities were clustered prior to regression analysis because of data heterogeneity. The compositional household feature data were also subjected to principal component analysis to diminish feature variable multicollinearity. The highest explanatory power was found for diarrhea deaths of under-5 children (R2 = 10-22 %), while those in the over-5 population were the least best explained (R2 = 0.3-7 %). Household features predicted diarrhea outcomes more accurately in the "advanced" housing municipality cluster (R2 = 16-22 %) than in the "mid-level" (R2 = 7-20 %) and "basic" (R2 = 6-12 %) ones (over-5 diarrhea deaths excluded). Under-5 children's diarrhea death prevalence was three times higher in the "basic" cluster than in the "advanced" cluster. Importantly, the impact of waste management was overall the largest of all household features, even larger than those of WASH, i.e., water supply, sanitation, and household drinking water treatment. This is surprising in the context of existing literature because WASH is generally regarded as the most important household factor affecting gastrointestinal health. In conclusion, public health interventions could benefit from customizing interventions for diarrhea outcomes, municipality types, and household features. Waste management's identified stronger association with diarrhea compared to WASH may have important implications beyond the water field and Brazil.

Circulation of Vaccine-derived Rotavirus G1P[8] in a Vulnerable Child Cohort in Rio de Janeiro

BACKGROUND

The expansion of rotavirus (RV) immunization in several countries reduced the burden of acute diarrheal disease (ADD) and diarrhea-associated mortality. Although community transmission of live attenuated monovalent rotavirus vaccine (G1P[8] RV1) virus has been demonstrated in children and household contacts, fecal shedding of these strains in neonates and infants under six weeks of age has never been demonstrated. The objective of the study was to assess ADD and rotavirus vaccine strain shedding before and after immunization through 24 months of age.

METHODS

This was a prospective cohort study in a low-resource community in which stool samples were collected from neonates from 15 to 45 days of age every 2 weeks, after both doses of G1P[8] RV1, and in subsequent ADD episodes until 2 years of age. RV was detected and genotyped in stool samples by RT-PCR.

RESULTS

We enrolled 242 participants who were followed for an average of 23 months. The specific prevalence of G1P[8] RV1 virus was 3.3% in neonates and infants less than six weeks of age, 50% after the first dose, and 25.6% after the second dose. Among the 70 participants with ADD, G1P[8] RV1 virus was identified in only one participant (1.4% prevalence).

CONCLUSIONS

In vaccinated children, there were no breakthrough infections with G1P[8] RV1 and ADD was rare supporting high vaccine effectiveness. We observed G1P[8] RV1 virus shedding among neonates and infants before the first vaccine dose, providing evidence of transmission of the vaccine strain from immunized children to those who are not yet vaccinated.

Rotavirus Vaccine Impact since Its Introduction in the National Immunization Program of Argentina

INTRODUCTION

Rotavirus (RV) is the most common cause of childhood diarrhea. Argentina introduced RV vaccination in the National Immunization Program in January 2015. This study evaluates the impact of RV vaccine implementation on the burden of acute diarrheal disease (ADD) and RV positive cases, and hospitalizations among children in Argentina.

METHODS

A counterfactual time-series analysis was performed. Data on ADD (2013-2018) and RV diarrhea (2012-2018) cases in children aged < 5 years were collected from the National Healthcare Surveillance System (clinical and laboratory data). Data on hospital discharges following ADD and RV diarrhea (2011-2017) were retrieved from the Health Statistics and Information Office. All data were classified by the age groups < 1 year, < 2 years, 2-5 years. Vaccine impact was defined as the difference between the predicted time trend (simulated using 2012-2014 data) and the actual post-vaccination data (2015-2018).

RESULTS

A significant reduction of 22.1% of notified ADD cases and 15.4% of hospital discharges following ADD among children < 2 years was observed in the 3 years after RV vaccine implementation. Data also showed a significant decline of 54.0% and 59.4% of notified RV cases in children < 2 and < 1 years, respectively, and a reduction of 39.3% and 40.8% in RV hospital discharges for the same age groups.

CONCLUSION

This study shows a significant reduction in notified ADD cases and RV cases and hospital discharges following ADD and RV cases in children < 2 years after RV vaccine introduction in Argentina in 2015.

Efficacy and safety of Bacillus clausii (O/C, N/R, SIN, T) probiotic combined with oral rehydration therapy (ORT) and zinc in acute diarrhea in children: a randomized, double-blind, placebo-controlled study in India

Background

Childhood diarrhea remains a major disease burden, particularly in developing countries, and is a leading cause of death in children aged < 5 years, worldwide. Treatment of acute diarrhea now includes probiotics to potentially reduce the duration and severity of the illness. This phase 3, randomized, placebo-controlled, double-blind study assessed the efficacy and safety of four strains (O/C, N/R, SIN, T) of Bacillus clausii probiotic (Enterogermina®) plus oral rehydration therapy (ORT) and zinc, versus placebo plus ORT and zinc, in infants and children in India with acute moderate diarrhea.

Methods

Patients aged 6 months to 5 years with acute moderate diarrhea (WHO 2005 definition) of < 48 h’ duration were randomly assigned to receive one mini bottle of either polyantibiotic-resistant B. clausii (oral suspension of 2 billion spores per 5 mL bottle) or matching placebo twice daily (morning and evening) for 5 days. Exclusion criteria included known hypersensitivity to B. clausii or excipients in the study treatment, or to other probiotics. Patients were admitted to hospital from Day 1 and discharged ≥6 h after diarrhea resolution, or a maximum of 5 days. The primary endpoint was duration of acute diarrhea from randomization to recovery. Secondary endpoints included frequency of stools, diapers with stools, or dehydration status.

Results

In total, 457 patients were randomized; 454 were treated. Similar proportions of patients showed recovery from diarrhea over the 120 h after randomization (97.0% in the B. clausii group [n = 227]; 98.0% on placebo [n = 227]). Median time to recovery was also similar: 42.83 (95% CI: 40.90–44.90) hours for B. clausii and 42.13 (95% CI: 39.80–43.87) hours for placebo. However, no statistically significant difference was observed between groups (hazard ratio = 0.93 [95% CI: 0.77–1.13]; p = 0.6968); nor were there statistically significant differences between groups for the secondary endpoints. Treatment with B. clausii was well tolerated with incidence of adverse events (9.7%) similar to that for placebo (12.3%).

Conclusions

No significant difference in efficacy between B. clausii and placebo was demonstrated. Sample size may have been inadequate to allow detection of a between-group difference in efficacy, given the mild/moderate severity (only ~ 20% of patients had nausea/vomiting or abdominal pains) and short duration of disease among subjects, the relatively late start of treatment (most were already on Day 2 of their disease episode when study treatment started) and the effectiveness of the standard of care with ORT and zinc in both treatment groups.

Trial registration

CTRI number CTRI/2018/10/016053. Registered on 17 October 2018. EudraCT number 2016-005165-31. Registered 14 May 2020 (retrospectively registered).

Supplementary Information

The online version contains supplementary material available at 10.1186/s40794-022-00166-6.

Viral metagenomics reveals diverse viruses in the fecal samples of children with diarrhea

Diarrhea is the third leading cause of death in developing countries in children under the age of five. About half a million children die of diarrhea every year, most of which in developing countries. Viruses are the main pathogen of diarrhea. In China, the fecal virome of children with diarrhea has been rarely studied. Using an unbiased viral metagenomics approach, we analyzed the fecal virome in children with diarrhea. Many DNA or RNA viruses associated with diarrhea identified in those fecal samples were mainly from six families of Adenoviridae, Astroviridae, Caliciviridae, Parvoviridae, Picornaviridae, and Reoviridae. Among them, the family of Caliciviridae accounts for the largest proportion of 78.42%, following with Adenoviridae (8.94%) and Picornaviridae (8.36%). In addition to those diarrhea-related viruses that have already been confirmed to cause human diarrhea, the viruses not associated with diarrhea were also identified including anellovirus and picobirnavirus. This study increased our understanding of diarrheic children fecal virome and provided valuable information for the prevention and treatment of viral diarrhea in this area.

•

Many DNA or RNA viruses associated with diarrhea were identified in this study.

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Viruses belonging to the family of Caliciviridae were the most main pathogen that induced children diarrhea.

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In addition to those diarrhea-related viruses, the viruses not associated with diarrhea were also identified.

Vaccines for preventing rotavirus diarrhoea: vaccines in use

BACKGROUND

Rotavirus is a common cause of diarrhoea, diarrhoea-related hospital admissions, and diarrhoea-related deaths worldwide. Rotavirus vaccines prequalified by the World Health Organization (WHO) include Rotarix (GlaxoSmithKline), RotaTeq (Merck), and, more recently, Rotasiil (Serum Institute of India Ltd.), and Rotavac (Bharat Biotech Ltd.).

OBJECTIVES

To evaluate rotavirus vaccines prequalified by the WHO for their efficacy and safety in children.

SEARCH METHODS

On 30 November 2020, we searched PubMed, the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (published in the Cochrane Library), Embase, LILACS, Science Citation Index Expanded, Social Sciences Citation Index, Conference Proceedings Citation Index-Science, Conference Proceedings Citation Index-Social Science & Humanities. We also searched the WHO ICTRP, ClinicalTrials.gov, clinical trial reports from manufacturers' websites, and reference lists of included studies, and relevant systematic reviews.

SELECTION CRITERIA

We selected randomized controlled trials (RCTs) conducted in children that compared rotavirus vaccines prequalified for use by the WHO with either placebo or no intervention.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial eligibility and assessed risk of bias. One author extracted data and a second author cross-checked them. We combined dichotomous data using the risk ratio (RR) and 95% confidence interval (CI). We stratified the analyses by under-five country mortality rate and used GRADE to evaluate evidence certainty.

MAIN RESULTS

Sixty trials met the inclusion criteria and enrolled a total of 228,233 participants. Thirty-six trials (119,114 participants) assessed Rotarix, 15 trials RotaTeq (88,934 participants), five trials Rotasiil (11,753 participants), and four trials Rotavac (8432 participants). Rotarix Infants vaccinated and followed up for the first year of life In low-mortality countries, Rotarix prevented 93% of severe rotavirus diarrhoea cases (14,976 participants, 4 trials; high-certainty evidence), and 52% of severe all-cause diarrhoea cases (3874 participants, 1 trial; moderate-certainty evidence).  In medium-mortality countries, Rotarix prevented 79% of severe rotavirus diarrhoea cases (31,671 participants, 4 trials; high-certainty evidence), and 36% of severe all-cause diarrhoea cases (26,479 participants, 2 trials; high-certainty evidence).  In high-mortality countries, Rotarix prevented 58% of severe rotavirus diarrhoea cases (15,882 participants, 4 trials; high-certainty evidence), and 27% of severe all-cause diarrhoea cases (5639 participants, 2 trials; high-certainty evidence). Children vaccinated and followed up for two years In low-mortality countries, Rotarix prevented 90% of severe rotavirus diarrhoea cases (18,145 participants, 6 trials; high-certainty evidence), and 51% of severe all-cause diarrhoea episodes (6269 participants, 2 trials; moderate-certainty evidence).   In medium-mortality countries, Rotarix prevented 77% of severe rotavirus diarrhoea cases (28,834 participants, 3 trials; high-certainty evidence), and 26% of severe all-cause diarrhoea cases (23,317 participants, 2 trials; moderate-certainty evidence).  In high-mortality countries, Rotarix prevented 35% of severe rotavirus diarrhoea cases (13,768 participants, 2 trials; moderate-certainty evidence), and 17% of severe all-cause diarrhoea cases (2764 participants, 1 trial; high-certainty evidence). RotaTeq Infants vaccinated and followed up for the first year of life In low-mortality countries, RotaTeq prevented 97% of severe rotavirus diarrhoea cases (5442 participants, 2 trials; high-certainty evidence).  In medium-mortality countries, RotaTeq prevented 79% of severe rotavirus diarrhoea cases (3863 participants, 1 trial; low-certainty evidence).  In high-mortality countries, RotaTeq prevented 57% of severe rotavirus diarrhoea cases (6775 participants, 2 trials; high-certainty evidence), but there is probably little or no difference between vaccine and placebo for severe all-cause diarrhoea (1 trial, 4085 participants; moderate-certainty evidence).  Children vaccinated and followed up for two years In low-mortality countries, RotaTeq prevented 96% of severe rotavirus diarrhoea cases (5442 participants, 2 trials; high-certainty evidence).  In medium-mortality countries, RotaTeq prevented 79% of severe rotavirus diarrhoea cases (3863 participants, 1 trial; low-certainty evidence).  In high-mortality countries, RotaTeq prevented 44% of severe rotavirus diarrhoea cases (6744 participants, 2 trials; high-certainty evidence), and 15% of severe all-cause diarrhoea cases (5977 participants, 2 trials; high-certainty evidence).  We did not identify RotaTeq studies reporting on severe all-cause diarrhoea in low- or medium-mortality countries. Rotasiil Rotasiil has not been assessed in any RCT in countries with low or medium child mortality. Infants vaccinated and followed up for the first year of life In high-mortality countries, Rotasiil prevented 48% of severe rotavirus diarrhoea cases (11,008 participants, 2 trials; high-certainty evidence), and resulted in little to no difference in severe all-cause diarrhoea cases (11,008 participants, 2 trials; high-certainty evidence). Children vaccinated and followed up for two years In high-mortality countries, Rotasiil prevented 44% of severe rotavirus diarrhoea cases (11,008 participants, 2 trials; high-certainty evidence), and resulted in little to no difference in severe all-cause diarrhoea cases (11,008 participants, 2 trials; high-certainty evidence). Rotavac Rotavac has not been assessed in any RCT in countries with low or medium child mortality.  Infants vaccinated and followed up for the first year of life In high-mortality countries, Rotavac prevented 57% of severe rotavirus diarrhoea cases (6799 participants, 1 trial; moderate-certainty evidence), and 16% of severe all-cause diarrhoea cases (6799 participants, 1 trial; moderate-certainty evidence). Children vaccinated and followed up for two years In high-mortality countries, Rotavac prevented 54% of severe rotavirus diarrhoea cases (6541 participants, 1 trial; moderate-certainty evidence); no Rotavac studies have reported on severe all-cause diarrhoea at two-years follow-up. Safety No increased risk of serious adverse events (SAEs) was detected with Rotarix (103,714 participants, 31 trials; high-certainty evidence), RotaTeq (82,502 participants, 14 trials; moderate to high-certainty evidence), Rotasiil (11,646 participants, 3 trials; high-certainty evidence), or Rotavac (8210 participants, 3 trials; moderate-certainty evidence). Deaths were infrequent and the analysis had insufficient evidence to show an effect on all-cause mortality. Intussusception was rare.  AUTHORS' CONCLUSIONS: Rotarix, RotaTeq, Rotasiil, and Rotavac prevent episodes of rotavirus diarrhoea. The relative effect estimate is smaller in high-mortality than in low-mortality countries, but more episodes are prevented in high-mortality settings as the baseline risk is higher. In high-mortality countries some results suggest lower efficacy in the second year. We found no increased risk of serious adverse events, including intussusception, from any of the prequalified rotavirus vaccines.

Differentiating severe and non-severe lower respiratory tract illness in patients hospitalized with influenza: Development of the Influenza Disease Evaluation and Assessment of Severity (IDEAS) scale

BACKGROUND

Experimental studies have shown that vaccination can reduce viral replication to attenuate progression of influenza-associated lower respiratory tract illness (LRTI). However, clinical studies are conflicting, possibly due to use of non-specific outcomes reflecting a mix of large and small airway LRTI lacking specificity for acute lung or organ injury.

METHODS

We developed a global ordinal scale to differentiate large and small airway LRTI in hospitalized adults with influenza using physiologic features and interventions (PFIs): vital signs, laboratory and radiographic findings, and clinical interventions. We reviewed the literature to identify common PFIs across 9 existing scales of pneumonia and sepsis severity. To characterize patients using this scale, we applied the scale to an antiviral clinical trial dataset where these PFIs were measured through routine clinical care in adults hospitalized with influenza-associated LRTI during the 2010-2013 seasons.

RESULTS

We evaluated 12 clinical parameters among 1020 adults; 210 (21%) had laboratory-confirmed influenza, with a median severity score of 4.5 (interquartile range, 2-8). Among influenza cases, median age was 63 years, 20% were hospitalized in the prior 90 days, 50% had chronic obstructive pulmonary disease, and 22% had congestive heart failure. Primary influencers of higher score included pulmonary infiltrates on imaging (48.1%), heart rate ≥110 beats/minute (41.4%), oxygen saturation <93% (47.6%) and respiratory rate >24 breaths/minute (21.0%). Key PFIs distinguishing patients with severity < or ≥8 (upper quartile) included infiltrates (27.1% vs 90.0%), temperature ≥ 39.1°C or <36.0°C (7.1% vs 27.1%), respiratory rate >24 breaths/minute (7.9% vs 47.1%), heart rate ≥110 beats/minute (29.3% vs 65.7%), oxygen saturation <90% (14.3% vs 31.4%), white blood cell count >15,000 (5.0% vs 27.2%), and need for invasive or non-invasive mechanical ventilation (2.1% vs 15.7%).

CONCLUSION

We developed a scale in adults hospitalized with influenza-associated LRTI demonstrating a broad distribution of physiologic severity which may be useful for future studies evaluating the disease attenuating effects of influenza vaccination or other therapeutics.

Human astrovirus types 1, 4 and 5 circulating among children with acute gastroenteritis in a rural Brazilian state, 2010-2016

This study combined conventional epidemiology of human astroviruses. From 2010 to 2016, 232 stool samples from children under 5 years of age were screened using NGS and conventional RT-PCR followed by genetic analysis in order to investigate the genotypic diversity of classical human astrovirus (HAstV) circulating in Tocantins State, Brazil. HAstV was detected in 16 cases (6.9%). Seven specimens (43.7%; 7/16) were positive according RT-PCR and next-generation sequencing (NGS) to investigate the molecular to both NGS and RT-PCR. NGS and RT-PCR individually revealed six (37.5%; 6/16) and three (18.8%; 3/16) additional positive samples, respectively. Sequencing of the HAstV-positive samples revealed HAstV-1a (9/16), HAstV-4c (3/16), and HAstV-5c (4/16) lineages.

Time series analysis of the relationship between diarrhea in children and Rota 2 vaccine in the Fanteakwa District of the eastern region of Ghana

BACKGROUND

Rotavirus is considered the main causal factor of severe gastroenteritis among infants and children globally. The association with severe rotavirus infection is mostly worse among the least developed countries, mainly due to inadequate access to medical care and poverty. This study was conducted to determine the seasonal effects in respect of diarrhea cases in children, the association between diarrhea cases and Rota2 vaccine in the Fanteakwa District of the Eastern Region of Ghana.

METHODS

The study compares monthly diarrhea cases against children vaccinated with Rota2 extracted from DHIMS2 spanning May 2012 to December 2017 in Fanteakwa District. A univariate association between diarrhea cases and children vaccinated with Rota 2 was conducted using the R-software version 3.4.4 with the use of forecast, tseries and TSAPred. Pearson Correlation coefficient was also computed between monthly diarrhea cases and Rota 2 as well as lagged values of Rota 2 and Diarrhea cases.

RESULTS

The study shows that February recorded the highest average number of diarrhea cases (172) over the period 2012 to 2017 with a standard deviation of 59. However, a one-way analysis of variance shows a significant difference amongst the monthly averages with an F-statistic of 0.042 and P-value of 0.064. It is observed that the correlations between each of the Rota2 doses and the lagged cases are positive, showing higher Rota2 doses a month ago ((Xt - 1),0.346 to 0.735), two months ago ((Xt - 2),0.383 to 0.746), three months ago ((Xt - 3), 0.330 to 0.737) and four months ago ((Xt - 4), 0.236 to 0.723) are associated with lower diarrhea cases. The results also show that an increase in the previous two month's Rota2 figures by 100 is associated with a significant decrease in the currently expected diarrhea cases by approximately 36.

CONCLUSION

Seasonal variations exist in the occurrence of diarrhea in children, with January recording the highest number of diarrhea cases (172). There is a relationship between episodes of diarrhea in children and Rota2 (p-value = 0.064); thus, the more children are vaccinated with Rota2, the less diarrhea cases are recorded. Diarrhea cases in Fanteakwa district are generally low, except 2013 and 2016 where the cases are higher than the rest of the other years.

Outdoor Residential Water Use Restrictions during Recent Drought Suppressed Disease Vector Abundance in Southern California

The California state government put restrictions on outdoor residential water use, including landscape irrigation, during the 2012-2016 drought. The public health implications of these actions are largely unknown, particularly with respect to mosquito-borne disease transmission. While residential irrigation facilitates persistence of mosquitoes by increasing the availability of standing water, few studies have investigated its effects on vector abundance. In two study sub-regions in the Los Angeles Basin, we examined the effect of outdoor residential water use restrictions on the abundance of the most important regional West Nile virus vector, Culex quinquefasciatus. Using spatiotemporal random forest models fit to Cx. abundance during drought and non-drought years, we generated counterfactual estimates of Cx. abundance under a hypothetical drought scenario without water use restrictions. We estimate that Cx. abundance would have been 44% and 39% larger in West Los Angeles and Orange counties, respectively, if outdoor water usage had remained unchanged. Our results suggest that drought, without mandatory water use restrictions, may counterintuitively increase the availability of larval habitats for vectors in naturally dry, highly irrigated settings and such mandatory water use restrictions may constrain Cx. abundance, which could reduce the risk of mosquito-borne disease while helping urban utilities maintain adequate water supplies.

Diarrheal Deaths After the Introduction of Rotavirus Vaccination in 4 Countries

BACKGROUND

We aim in our analysis to estimate the reduction of diarrhea-related mortality rates after introduction of a rotavirus vaccine in subregions of 4 Latin American countries.

METHODS

We selected diarrhea-related deaths from individual-level data from death certificates in Brazil, Colombia, Ecuador, and Mexico. Counts were aggregated by region, year and month, and age group for each country. We ran an interrupted time-series analysis using Poisson regression to obtain seasonal and trend-adjusted estimates of impact. Results are reported as percentages (1 - mortality rate ratio).

RESULTS

We found a reduction in diarrhea-related mortality in children <5 years old of 18% (95% confidence interval [CI], 15 to 20) for Mexico, 39% (95% CI, 35 to 44) for Colombia, 19 (95% CI, 17 to 22) for Brazil, and -26% (95% CI, -40 to -14) for Ecuador. Using wavelet analyses, we found a reduction of 6- and 12-month seasonality in Brazil, Colombia, and Mexico. We also found that the increased reduction of diarrhea-related deaths was larger with greater prevaccine burden of diarrhea in infants.

CONCLUSIONS

Our findings and available evidence support the recommendation from the World Health Organization for the monovalent and/or pentavalent rotavirus vaccine in countries worldwide. We found an increased benefit in those settings with a higher burden of infant diarrhea-related deaths.

Early Evidence of Inactivated Enterovirus 71 Vaccine Impact Against Hand, Foot, and Mouth Disease in a Major Center of Ongoing Transmission in China, 2011-2018: A Longitudinal Surveillance Study

BACKGROUND

Enterovirus 71 (EV71) is a major causative agent of hand, foot, and mouth disease (HFMD), associated with severe manifestations of the disease. Pediatric immunization with inactivated EV71 vaccine was initiated in 2016 in the Asia-Pacific region, including China. We analyzed a time series of HFMD cases attributable to EV71, coxsackievirus A16 (CA16), and other enteroviruses in Chengdu, a major transmission center in China, to assess early impacts of immunization.

METHODS

Reported HFMD cases were obtained from China's notifiable disease surveillance system. We compared observed postvaccination incidence rates during 2017-2018 with counterfactual predictions made from a negative binomial regression and a random forest model fitted to prevaccine years (2011-2015). We fit a change point model to the full time series to evaluate whether the trend of EV71 HFMD changed following vaccination.

RESULTS

Between 2011 and 2018, 279 352 HFMD cases were reported in the study region. The average incidence rate of EV71 HFMD in 2017-2018 was 60% (95% prediction interval [PI], 41%-72%) lower than predicted in the absence of immunization, corresponding to an estimated 6911 (95% PI, 3246-11 542) EV71 cases averted over 2 years. There were 52% (95% PI, 42%-60%) fewer severe HFMD cases than predicted. However, the incidence rate of non-CA16 and non-EV71 HFMD was elevated in 2018. We identified a significant decline in the trend of EV71 HFMD 4 months into the postvaccine period.

CONCLUSIONS

We provide the first real-world evidence that programmatic vaccination against EV71 is effective against childhood HFMD and present an approach to detect early vaccine impact or intended consequences from surveillance data.

Viral gastroenteritis in Tocantins, Brazil: characterizing the diversity of human adenovirus F through next-generation sequencing and bioinformatics

Human enteric adenovirus species F (HAdV-F) is one of the most common pathogens responsible for acute gastroenteritis worldwide. Brazil is a country with continental dimensions where continuous multiregional surveillance is vital to establish a more complete picture of the epidemiology of HAdV-F. The aim of the current study was to investigate the molecular epidemiology of HAdV-F using full-genome data in rural and low-income urban areas in northern Brazil. This will allow a genetic comparison between Brazilian and global HAdV-F strains. The frequency of HAdV-F infections in patients with gastroenteritis and molecular typing of positive samples within this period was also analysed. A total of 251 stool samples collected between 2010 and 2016 from patients with acute gastroenteritis were screened for HAdV-F using next-generation sequencing techniques. HAdV-F infection was detected in 57.8 % (145/251) of samples. A total of 137 positive samples belonged to HAdV-F41 and 7 to HAdV-F40. HAdV-F40/41 dual infection was found in one sample. Detection rates did not vary significantly according to the year. Single HAdV-F infections were detected in 21.9 % (55/251) of samples and mixed infections in 37.4 % (94/251), with RVA/HAdV-F being the most frequent association (21.5 %; 54/251). Genetic analysis indicated that the HAdV-F strains circulating in Brazil were closely related to worldwide strains, and the existence of some temporal order was not observed. This is the first large-scale HAdV-F study in Brazil in which whole-genome data and DNA sequence analyses were used to characterize HAdV-F strains. Expanding the viral genome database could improve overall genotyping success and assist the National Center for Biotechnology Information (NCBI)/GenBank in standardizing the HAdV genome records by providing a large set of annotated HAdV-F genomes.

Rotavirus A shedding and HBGA host genetic susceptibility in a birth community-cohort, Rio de Janeiro, Brazil, 2014-2018

Recent studies have investigated whether the human histo-blood group antigen (HBGAs) could affect the effectiveness of the oral rotavirus vaccines, suggesting secretor positive individuals develop a more robust response. We investigated the Rotavirus A (RVA) shedding in association with the host susceptibility profile in children from a birth community-cohort in Rio de Janeiro, Brazil, from 2014 to 2018. A total of 132 children were followed-up between 0 to 11-month-old, stool samples were collected before/after the 1st/2nd RV1 vaccination doses and saliva samples were collected during the study. RVA shedding was screened by RT-qPCR and G/P genotypes determined by multiplex RT-PCR and/or Sanger nucleotide sequencing. The sequencing indicated an F167L amino acid change in the RV1 VP8* P[8] in 20.5% of shedding follow-ups and these mutant subpopulations were quantified by pyrosequencing. The HBGA/secretor status was determined and 80.3% of the children were secretors. Twenty-one FUT2 gene SNPs were identified and two new mutations were observed. The mutant F167L RV1 VP8* P[8] was detected significantly more in Le (a+b+) secretors (90.5%) compared to non-secretors and even to secretors Le (a-b+) (9.5%). The study highlights the probable association between RV1 shedding and HBGAs as a marker for evaluating vaccine strain host susceptibility.

The control of diarrhea, the case of a rotavirus vaccine

[No disponible]

Impact assessment of the incorporation of the rotavirus vaccine in the province of San Luis - Argentina

Rotavirus (RV) is the main cause of acute gastroenteritis (AGE) in young children. The San Luis province of Argentina introduced RV vaccination in May 2013. We estimate vaccine impact (RVI) using real-world data. Data on all-cause AGE cases and AGE-related hospitalisations for San Luis and the adjacent Mendoza province (control group) were obtained and analysed by interrupted time-series methods. Regardless of the model used for counterfactual predictions, we estimated a reduction in the number of all-cause AGE cases of 20-25% and a reduction in AGE-related hospitalisations of 55-60%. The vaccine impact was similar for each age group considered (<1 year, <2 years and <5 years). RV vaccination was estimated to have reduced direct medical costs in the province by about 4.5 million pesos from May 2013 to December 2014. Similar to previous studies, we found a higher impact of RV vaccination in preventing severe all-cause AGE cases requiring hospitalisation than in preventing all-cases AGE cases presenting for medical care. An assessment of the economic value of RV vaccination could take other benefits into account in addition to the avoided medical costs and the costs of vaccination.

The (in)visible health risks of climate change

This paper scrutinizes the assertion that knowledge gaps concerning health risks from climate change are unjust, and must be addressed, because they hinder evidence-led interventions to protect vulnerable populations. First, we construct a taxonomy of six inter-related forms of invisibility (social marginalization, forced invisibility by migrants, spatial marginalization, neglected diseases, mental health, uneven climatic monitoring and forecasting) which underlie systematic biases in current understanding of these risks in Latin America, and advocate an approach to climate-health research that draws on intersectionality theory to address these inter-relations. We propose that these invisibilities should be understood as outcomes of structural imbalances in power and resources rather than as haphazard blindspots in scientific and state knowledge. Our thesis, drawing on theories of governmentality, is that context-dependent tensions condition whether or not benefits of making vulnerable populations legible to the state outweigh costs. To be seen is to be politically counted and eligible for rights, yet evidence demonstrates the perils of visibility to disempowered people. For example, flood-relief efforts in remote Amazonia expose marginalized urban river-dwellers to the traumatic prospect of forced relocation and social and economic upheaval. Finally, drawing on research on citizenship in post-colonial settings, we conceptualize climate change as an 'open moment' of political rupture, and propose strategies of social accountability, empowerment and trans-disciplinary research which encourage the marginalized to reach out for greater power. These achievements could reduce drawbacks of state legibility and facilitate socially-just governmental action on climate change adaptation that promotes health for all.

Vaccines for preventing rotavirus diarrhoea: vaccines in use

BACKGROUND

Rotavirus results in more diarrhoea-related deaths in children under five years than any other single agent in countries with high childhood mortality. It is also a common cause of diarrhoea-related hospital admissions in countries with low childhood mortality. Rotavirus vaccines that have been prequalified by the World Health Organization (WHO) include a monovalent vaccine (RV1; Rotarix, GlaxoSmithKline), a pentavalent vaccine (RV5; RotaTeq, Merck), and, more recently, another monovalent vaccine (Rotavac, Bharat Biotech).

OBJECTIVES

To evaluate rotavirus vaccines prequalified by the WHO (RV1, RV5, and Rotavac) for their efficacy and safety in children.

SEARCH METHODS

On 4 April 2018 we searched MEDLINE (via PubMed), the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (published in the Cochrane Library), Embase, LILACS, and BIOSIS. We also searched the WHO ICTRP, ClinicalTrials.gov, clinical trial reports from manufacturers' websites, and reference lists of included studies and relevant systematic reviews.

SELECTION CRITERIA

We selected randomized controlled trials (RCTs) in children comparing rotavirus vaccines prequalified for use by the WHO versus placebo or no intervention.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial eligibility and assessed risks of bias. One review author extracted data and a second author cross-checked them. We combined dichotomous data using the risk ratio (RR) and 95% confidence interval (CI). We stratified the analysis by country mortality rate and used GRADE to evaluate evidence certainty.

MAIN RESULTS

Fifty-five trials met the inclusion criteria and enrolled a total of 216,480 participants. Thirty-six trials (119,114 participants) assessed RV1, 15 trials (88,934 participants) RV5, and four trials (8432 participants) Rotavac. RV1 Children vaccinated and followed up the first year of life In low-mortality countries, RV1 prevents 84% of severe rotavirus diarrhoea cases (RR 0.16, 95% CI 0.09 to 0.26; 43,779 participants, 7 trials; high-certainty evidence), and probably prevents 41% of cases of severe all-cause diarrhoea (RR 0.59, 95% CI 0.47 to 0.74; 28,051 participants, 3 trials; moderate-certainty evidence). In high-mortality countries, RV1 prevents 63% of severe rotavirus diarrhoea cases (RR 0.37, 95% CI 0.23 to 0.60; 6114 participants, 3 trials; high-certainty evidence), and 27% of severe all-cause diarrhoea cases (RR 0.73, 95% CI 0.56 to 0.95; 5639 participants, 2 trials; high-certainty evidence). Children vaccinated and followed up for two years In low-mortality countries, RV1 prevents 82% of severe rotavirus diarrhoea cases (RR 0.18, 95% CI 0.14 to 0.23; 36,002 participants, 9 trials; high-certainty evidence), and probably prevents 37% of severe all-cause diarrhoea episodes (rate ratio 0.63, 95% CI 0.56 to 0.71; 39,091 participants, 2 trials; moderate-certainty evidence). In high-mortality countries RV1 probably prevents 35% of severe rotavirus diarrhoea cases (RR 0.65, 95% CI 0.51 to 0.83; 13,768 participants, 2 trials; high-certainty evidence), and 17% of severe all-cause diarrhoea cases (RR 0.83, 95% CI 0.72 to 0.96; 2764 participants, 1 trial; moderate-certainty evidence). No increased risk of serious adverse events (SAE) was detected (RR 0.88 95% CI 0.83 to 0.93; high-certainty evidence). There were 30 cases of intussusception reported in 53,032 children after RV1 vaccination and 28 cases in 44,214 children after placebo or no intervention (RR 0.70, 95% CI 0.46 to 1.05; low-certainty evidence). RV5 Children vaccinated and followed up the first year of life In low-mortality countries, RV5 probably prevents 92% of severe rotavirus diarrhoea cases (RR 0.08, 95% CI 0.03 to 0.22; 4132 participants, 5 trials; moderate-certainty evidence). We did not identify studies reporting on severe all-cause diarrhoea in low-mortality countries. In high-mortality countries, RV5 prevents 57% of severe rotavirus diarrhoea (RR 0.43, 95% CI 0.29 to 0.62; 5916 participants, 2 trials; high-certainty evidence), but there is probably little or no difference between vaccine and placebo for severe all-cause diarrhoea (RR 0.80, 95% CI 0.58 to 1.11; 1 trial, 4085 participants; moderate-certainty evidence). Children vaccinated and followed up for two years In low-mortality countries, RV5 prevents 82% of severe rotavirus diarrhoea cases (RR 0.18, 95% CI 0.08 to 0.39; 7318 participants, 4 trials; moderate-certainty evidence). We did not identify studies reporting on severe all-cause diarrhoea in low-mortality countries. In high-mortality countries, RV5 prevents 41% of severe rotavirus diarrhoea cases (RR 0.59, 95% CI 0.43 to 0.82; 5885 participants, 2 trials; high-certainty evidence), and 15% of severe all-cause diarrhoea cases (RR 0.85, 95% CI 0.75 to 0.98; 5977 participants, 2 trials; high-certainty evidence). No increased risk of serious adverse events (SAE) was detected (RR 0.93 95% CI 0.86 to 1.01; moderate to high-certainty evidence). There were 16 cases of intussusception in 43,629 children after RV5 vaccination and 20 cases in 41,866 children after placebo (RR 0.77, 95% CI 0.41 to 1.45; low-certainty evidence). Rotavac Children vaccinated and followed up the first year of life Rotavac has not been assessed in any RCT in countries with low child mortality. In India, a high-mortality country, Rotavac probably prevents 57% of severe rotavirus diarrhoea cases (RR 0.43, 95% CI 0.30 to 0.60; 6799 participants, moderate-certainty evidence); the trial did not report on severe all-cause diarrhoea at one-year follow-up. Children vaccinated and followed up for two years Rotavac probably prevents 54% of severe rotavirus diarrhoea cases in India (RR 0.46, 95% CI 0.35 to 0.60; 6541 participants, 1 trial; moderate-certainty evidence), and 16% of severe all-cause diarrhoea cases (RR 0.84, 95% CI 0.71 to 0.98; 6799 participants, 1 trial; moderate-certainty evidence). No increased risk of serious adverse events (SAE) was detected (RR 0.93 95% CI 0.85 to 1.02; moderate-certainty evidence). There were eight cases of intussusception in 5764 children after Rotavac vaccination and three cases in 2818 children after placebo (RR 1.33, 95% CI 0.35 to 5.02; very low-certainty evidence). There was insufficient evidence of an effect on mortality from any rotavirus vaccine (198,381 participants, 44 trials; low- to very low-certainty evidence), as the trials were not powered to detect an effect at this endpoint.

AUTHORS' CONCLUSIONS

RV1, RV5, and Rotavac prevent episodes of rotavirus diarrhoea. Whilst the relative effect estimate is smaller in high-mortality than in low-mortality countries, there is a greater number of episodes prevented in these settings as the baseline risk is much higher. We found no increased risk of serious adverse events. 21 October 2019 Up to date All studies incorporated from most recent search All published trials found in the last search (4 Apr, 2018) were included and 15 ongoing studies are currently awaiting completion (see 'Characteristics of ongoing studies').

Functional antibodies as immunological endpoints to evaluate protective immunity against Shigella

The development, clinical advancement and licensure of vaccines, and monitoring of vaccine effectiveness could be expedited and simplified by the ability to measure immunological endpoints that can predict a favorable clinical outcome. Antigen-specific and functional antibodies have been described in the context of naturally acquired immunity and vaccination against Shigella, and their presence in serum has been associated with reduced risk of disease in human subjects. The relevance of these antibodies as correlates of protective immunity, their mechanistic contribution to protection (e.g. target antigens, interference with pathogenesis, and participation in microbial clearance), and factors that influence their magnitude and makeup (e.g. host age, health condition, and environment) are important considerations that need to be explored. In addition to facilitating vaccine evaluation, immunological correlates of protection could be useful for identifying groups at risk and advancing immune therapies. Herein we discuss the precedent and value of functional antibodies as immunological endpoints to predict vaccine efficacy and the relevance of functional antibody activity to evaluate protective immunity against shigellosis.

Prevalence and molecular typing of rotavirus in children with acute diarrhoea in Northeastern Colombia

After the introduction of the rotavirus vaccine, the number of rotavirus-associated deaths and the predicted annual rotavirus detection rate had slightly declined worldwide. Taking in account that in Colombia, Rotarix vaccine was introduced in 2009, the purpose of this study was to evaluate the presence of rotavirus A in children under five years who were treated for acute diarrhoea in Bucaramanga, Colombia and, moreover, to determine the genotypes of rotavirus present in those children. We performed an analytical cross-sectional study of rotavirus A in faecal samples from children up to five years of age. Stool samples were screened for rotavirus A using a lateral-flow immunochromatographic assay and confirmed using a VP6 sandwich ELISA. Genotyping of rotavirus A-positive samples was performed by PCR and sequencing of VP7 and VP4 genes. The overall prevalence of rotavirus was 30.53% (95% confidence interval [CI] 21.2 - 39.7). Most of the children with rotavirus (86.2%) had received two doses of the rotavirus vaccine. G3 strains accounted for the vast majority of cases (82.8%), followed by G12 strains (13.8%) and G3/G9 coinfections (3.4%). Among the P genotypes, P[8] was the most prevalent (69%), followed by P[9] (31%). The most common G[P] genotype combination was G3P[8], followed by G3P[9]. The main finding in this study was that rotavirus, in a Colombian region, is still an important pathogen in children under five years old, previously vaccinated. The results showed that different factors, such as kindergarten attendance, could explain the epidemiology and transmission of rotavirus in Bucaramanga.

Emergence of G12P[6] rotavirus strains among hospitalised children with acute gastroenteritis in Belém, Northern Brazil, following introduction of a rotavirus vaccine

Species A rotavirus still remains a major cause of acute gastroenteritis in infants and young children. Globally, six genotypes (G1P[8], G2P[4], G3P[8], G4P[8], G9P[8] and G12P[8]) account for >90% of circulating strains; however, genotype G12 in combination with P[6] or P[9] has been detected at increasing rates. We sought to broaden our knowledge about the rotavirus strains circulating during the early post-vaccine-introduction period. Stool samples were obtained from children hospitalised for acute gastroenteritis in Belém, Northern Brazil, from May 2008 to May 2011 and examined by reverse transcription polymerase chain reaction and nucleotide sequencing. A total of 122 out of the original 1076 rotavirus strains were judged to be non-typeable in the first analysis and were therefore re-examined. G2P[4] was the most prevalent genotype (58.0%), followed by G1P[8] (16.9%), and G12P[6] (7.5%). G12P[6] strains were identified at similar rates during the first (2.5%) and second (3.9%) years, and the rate jumped to 15.6% in the third year. Analysis of VP7 sequences of the G12P[6] strains showed that they belonged to lineage III. In addition, co-circulating G12P[6] strains displaying long and short RNA patterns were found to belong to the Wa-like and DS-1-like constellation, respectively. Additional unusual circulating strains G12P[9] and G3P[9] were also identified. This hospital-based study showed a high prevalence of G12P[6] strains in the third year of surveillance. Our results highlight the need for continuous longitudinal monitoring of circulating rotavirus strains after introduction of rotavirus vaccines in Brazil and elsewhere.

'Don't put your head under water': enteric viruses in Brazilian recreational waters

Like in many other countries, virologic analyses are not routinely performed in Brazil in monitoring water quality for recreational purposes. We surveyed current research regarding viral contamination of recreational water environments in Brazil. Among the enteric viruses studied in Brazilian recreational waters, we highlight adenoviruses, rotaviruses, enteroviruses and noroviruses. Although there has been relatively little research on outbreaks related to bathing in recreational water environments in Brazil, noroviruses and adenoviruses are the viruses that are most often related to outbreaks. Better surveillance of the occurrence of enteric viruses in water could improve the assessment of risk to human health as well as indicate the sources of contamination and thus demonstrate the importance of adequate environmental sanitation.

Vaccines for preventing rotavirus diarrhoea: vaccines in use

BACKGROUND

Rotavirus results in more diarrhoea-related deaths in children under five years than any other single agent in countries with high childhood mortality. It is also a common cause of diarrhoea-related hospital admissions in countries with low childhood mortality. Rotavirus vaccines that have been prequalified by the World Health Organization (WHO) include a monovalent vaccine (RV1; Rotarix, GlaxoSmithKline), a pentavalent vaccine (RV5; RotaTeq, Merck), and, more recently, another monovalent vaccine (Rotavac, Bharat Biotech).

OBJECTIVES

To evaluate rotavirus vaccines prequalified by the WHO (RV1, RV5, and Rotavac) for their efficacy and safety in children.

SEARCH METHODS

On 4 April 2018 we searched MEDLINE (via PubMed), the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (published in the Cochrane Library), Embase, LILACS, and BIOSIS. We also searched the WHO ICTRP, ClinicalTrials.gov, clinical trial reports from manufacturers' websites, and reference lists of included studies and relevant systematic reviews.

SELECTION CRITERIA

We selected randomized controlled trials (RCTs) in children comparing rotavirus vaccines prequalified for use by the WHO versus placebo or no intervention.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial eligibility and assessed risks of bias. One review author extracted data and a second author cross-checked them. We combined dichotomous data using the risk ratio (RR) and 95% confidence interval (CI). We stratified the analysis by country mortality rate and used GRADE to evaluate evidence certainty.

MAIN RESULTS

Fifty-five trials met the inclusion criteria and enrolled a total of 216,480 participants. Thirty-six trials (119,114 participants) assessed RV1, 15 trials (88,934 participants) RV5, and four trials (8432 participants) Rotavac.RV1 Children vaccinated and followed up the first year of life In low-mortality countries, RV1 prevents 84% of severe rotavirus diarrhoea cases (RR 0.16, 95% CI 0.09 to 0.26; 43,779 participants, 7 trials; high-certainty evidence), and probably prevents 41% of cases of severe all-cause diarrhoea (RR 0.59, 95% CI 0.47 to 0.74; 28,051 participants, 3 trials; moderate-certainty evidence). In high-mortality countries, RV1 prevents 63% of severe rotavirus diarrhoea cases (RR 0.37, 95% CI 0.23 to 0.60; 6114 participants, 3 trials; high-certainty evidence), and 27% of severe all-cause diarrhoea cases (RR 0.73, 95% CI 0.56 to 0.95; 5639 participants, 2 trials; high-certainty evidence).Children vaccinated and followed up for two yearsIn low-mortality countries, RV1 prevents 82% of severe rotavirus diarrhoea cases (RR 0.18, 95% CI 0.14 to 0.23; 36,002 participants, 9 trials; high-certainty evidence), and probably prevents 37% of severe all-cause diarrhoea episodes (rate ratio 0.63, 95% CI 0.56 to 0.71; 39,091 participants, 2 trials; moderate-certainty evidence). In high-mortality countries RV1 probably prevents 35% of severe rotavirus diarrhoea cases (RR 0.65, 95% CI 0.51 to 0.83; 13,768 participants, 2 trials; high-certainty evidence), and 17% of severe all-cause diarrhoea cases (RR 0.83, 95% CI 0.72 to 0.96; 2764 participants, 1 trial; moderate-certainty evidence).No increased risk of serious adverse events (SAE) was detected (RR 0.88 95% CI 0.83 to 0.93; high-certainty evidence). There were 30 cases of intussusception reported in 53,032 children after RV1 vaccination and 28 cases in 44,214 children after placebo or no intervention (RR 0.70, 95% CI 0.46 to 1.05; low-certainty evidence).RV5 Children vaccinated and followed up the first year of life In low-mortality countries, RV5 probably prevents 92% of severe rotavirus diarrhoea cases (RR 0.08, 95% CI 0.03 to 0.22; 4132 participants, 5 trials; moderate-certainty evidence). We did not identify studies reporting on severe all-cause diarrhoea in low-mortality countries. In high-mortality countries, RV5 prevents 57% of severe rotavirus diarrhoea (RR 0.43, 95% CI 0.29 to 0.62; 5916 participants, 2 trials; high-certainty evidence), but there is probably little or no difference between vaccine and placebo for severe all-cause diarrhoea (RR 0.80, 95% CI 0.58 to 1.11; 1 trial, 4085 participants; moderate-certainty evidence).Children vaccinated and followed up for two yearsIn low-mortality countries, RV5 prevents 82% of severe rotavirus diarrhoea cases (RR 0.18, 95% CI 0.08 to 0.39; 7318 participants, 4 trials; moderate-certainty evidence). We did not identify studies reporting on severe all-cause diarrhoea in low-mortality countries. In high-mortality countries, RV5 prevents 41% of severe rotavirus diarrhoea cases (RR 0.59, 95% CI 0.43 to 0.82; 5885 participants, 2 trials; high-certainty evidence), and 15% of severe all-cause diarrhoea cases (RR 0.85, 95% CI 0.75 to 0.98; 5977 participants, 2 trials; high-certainty evidence).No increased risk of serious adverse events (SAE) was detected (RR 0.93 95% CI 0.86 to 1.01; moderate to high-certainty evidence). There were 16 cases of intussusception in 43,629 children after RV5 vaccination and 20 cases in 41,866 children after placebo (RR 0.77, 95% CI 0.41 to 1.45; low-certainty evidence).Rotavac Children vaccinated and followed up the first year of life Rotavac has not been assessed in any RCT in countries with low child mortality. In India, a high-mortality country, Rotavac probably prevents 57% of severe rotavirus diarrhoea cases (RR 0.43, 95% CI 0.30 to 0.60; 6799 participants, moderate-certainty evidence); the trial did not report on severe all-cause diarrhoea at one-year follow-up.Children vaccinated and followed up for two yearsRotavac probably prevents 54% of severe rotavirus diarrhoea cases in India (RR 0.46, 95% CI 0.35 to 0.60; 6541 participants, 1 trial; moderate-certainty evidence), and 16% of severe all-cause diarrhoea cases (RR 0.84, 95% CI 0.71 to 0.98; 6799 participants, 1 trial; moderate-certainty evidence).No increased risk of serious adverse events (SAE) was detected (RR 0.93 95% CI 0.85 to 1.02; moderate-certainty evidence). There were eight cases of intussusception in 5764 children after Rotavac vaccination and three cases in 2818 children after placebo (RR 1.33, 95% CI 0.35 to 5.02; very low-certainty evidence).There was insufficient evidence of an effect on mortality from any rotavirus vaccine (198,381 participants, 44 trials; low- to very low-certainty evidence), as the trials were not powered to detect an effect at this endpoint.

AUTHORS' CONCLUSIONS

RV1, RV5, and Rotavac prevent episodes of rotavirus diarrhoea. Whilst the relative effect estimate is smaller in high-mortality than in low-mortality countries, there is a greater number of episodes prevented in these settings as the baseline risk is much higher. We found no increased risk of serious adverse events.

Equity and impact: Ontario's infant rotavirus immunization program five years following implementation. A population-based cohort study

BACKGROUND

Ontario implemented a publicly-funded rotavirus (RV) immunization program in 2011. Our objectives were to evaluate its impact on hospitalizations and emergency department (ED) visits for acute gastroenteritis (AGE) five years after implementation.

METHODS

We performed a population-based longitudinal retrospective cohort study to identify hospitalizations and ED visits for RV-AGE and overall AGE in all age groups using ICD-10 codes between August 1, 2005 and March 31, 2016. A negative binomial regression model that included the effect of time was used to calculate rates, rate ratios (RRs) and 95% confidence intervals (CIs) for AGE before and after the program's implementation, after adjusting for age, seasonality and secular trends. We examined the seasonality of RV-AGE hospitalizations among children under five before and after the program and explored its equity impact.

RESULTS

Following program implementation, RV-AGE hospitalizations and ED visits among children under five years declined by 76% (RR 0.24, 95% CI 0.20-0.28) and 68% (RR 0.32, 95% CI 0.21-0.50), respectively. In addition, hospitalizations and ED visits for overall AGE declined by 38% (RR 0.62, 95% CI 0.59-0.65) and 26% (RR 0.74, 95% CI 0.73-0.76), respectively, among children under age five. Significant reductions in both outcomes were also found across a range of age-strata. In the pre-program period, the mean monthly hospitalization rate for RV-AGE among children residing in the most marginalized neighbourhoods was 33% higher than those residing in the least marginalized (RR 1.33, 95% CI 1.17-1.52), this disparity was not evident in the program period (RR 0.95, 95% CI 0.69-1.32). We found no evidence of a seasonal shift in rotavirus pediatric hospitalizations.

INTERPRETATION

The introduction of routine infant rotavirus immunization has had a substantial population impact in Ontario. Our study confirms herd effects and suggests the program may have reduced previous inequities in the burden of pediatric rotavirus hospitalizations.

Experiences with rotavirus vaccines: can we improve rotavirus vaccine impact in developing countries?

Rotavirus vaccines have been introduced into over 95 countries globally and demonstrate substantial impact in reducing diarrheal mortality and diarrheal hospitalizations in young children. The vaccines are also considered by WHO as "very cost effective" interventions for young children, particularly in countries with high diarrheal disease burden. Yet the full potential impact of rotavirus immunization is yet to be realized. Large countries with big birth cohorts and where disease burden is high in Africa and Asia have not yet implemented rotavirus vaccines at all or at scale. Significant advances have been made demonstrating the impact of the vaccines in low- and lower-middle income countries, yet the modest effectiveness of the vaccines in these settings is challenging. Current research highlights these challenges and considers alternative strategies to overcome them, including alternative immunization schedules and host factors that may inform us of new opportunities.

The evolving epidemiology of rotavirus A infection in Brazil a decade after the introduction of universal vaccination with Rotarix®

Background

Brazil introduced the monovalent rotavirus vaccine (Rotarix®) in 2006. This study aimed to assess the epidemiology and genotype distribution of species-A rotavirus (RVA) in Brazil, comparing the pre- and post-vaccination periods.

Methods

Laboratory-based RVA surveillance included 866 municipalities in 22 Brazilian states, over a 21-year period. A total of 16,185 children with diarrheal diseases (DD) aged up to 12 years between 1996 and 2005 (pre-vaccination period, n = 7030) and from 2006 to 2017 (post-vaccination period, n = 9155) were enrolled. RVA was detected using ELISA immune assay and/or polyacrylamide gel electrophoresis and genotyped using nested PCR and/or nucleotide sequencing. RVA-positivity and genotypes detection rates were compared in distinct periods and age groups and Rotarix vaccination status.

Results

RVA-positivity in pre- and post-vaccination periods was, respectively: 4–11 months bracket, 33.3% (668/2006) and 16.3% (415/2547) (p <  0.001); 12–24 months, 28.2% (607/2154) and 22.2% (680/3068) (p <  0.001); 25–48 months, 17.4% (215/1235) and 29.4% (505/1720) (p <  0.001). Genotypes distribution in the pre- and post-vaccination periods was, respectively: G1P [8]/G1P[Not Typed], 417/855 (48.8%) and 118/1835 (6.4%) (p <  0.001); G2P [4]/G2P[NT], 47/855 (5.5%) and 838/1835 (45.7%) (p <  0.001); G3P [8]/G3P[NT], 55/855 (6.4%) and 253/1835 (13.8%) (p <  0.001); G9P [8]/G9P[NT], 238/855 (27.8%) and 152/1835 (8.3%) (p <  0.001); G12P [8]/G129P[NT], 0/871 (0%) and 249/1835(13.6%) (p <  0.001). Concerning infants aged 4–11 months, RVA frequency in fully vaccinated and non-vaccinated individuals was 11.9% (125/1052) and 24.5% (58/237) (p <  0.001), respectively. In children aged 12–24 months, RVA detection rate was 18.1% (253/1395) and 29.6% (77/260) (p <  0.001), for the vaccinated and non-vaccinated individuals, respectively (p <  0.001).

Conclusions

RVA infection was significantly less frequent in children aged ≤2 years with DD after implementing vaccination, mainly among vaccinated children. It was also observed a decrease of P [8] circulation and emergence of G2P[4] in 2005, and afterwards in the post-vaccine era, with spreading of G12P[8] in 2014–2015 and of G3P[8] in 2017. Continuous RVA surveillance must be carried out in this scenario.

Mixed Viral-Bacterial Infections and Their Effects on Gut Microbiota and Clinical Illnesses in Children

Acute gastroenteritis remains a major cause of morbidity and mortality among young children worldwide. It accounts for approximately 1.34 million deaths annually in children younger than five years. Infection can be caused by viral, bacterial and/or parasitic microorganisms. Dysbiosis due to such infections could dramatically affect disease prognosis as well as development of chronic illness. The aim of this study was to analyze gut microbiome and clinical outcomes in young children suffering from viral or mixed viral-bacterial infection. We evaluated gut microbiota composition in children suffering from viral or mixed viral-bacterial infection with two major viruses rotavirus (RV) and norovirus (NoV) and two pathogenic bacteria [Enteroaggregative E. coli (EAEC), and Enteropathogenic E. coli (EPEC)]. We sequenced 16S ribosomal RNA (V4 region) genes using Illumina MiSeq in 70 hospitalized children suffering from gastroenteric infections plus nine healthy controls. The study summarized Operational Taxonomic Unit (OTU) abundances with the Bray-Curtis index and performed a non-metric multidimensional scaling analysis to visualize microbiome similarities. We used a permutational multivariate analyses of variance to test the significance of group differences. We also analyzed the correlation between microbiome changes and clinical outcomes. Our data demonstrated a significant increase in the severity score in children with viral-bacterial mixed infections compared to those with virus infections alone. Statistical analysis by overall relative abundance denoted lesser proportions of Bacteroides in the infected children, whereas Bifidobacteriaceae richness was more prominent in the bacterial-viral mixed infections. Pairwise differences of gut microbiota were significantly higher in RV + EAEC (P = 0.009) and NoV + EAEC (P = 0.009) co-infections, compared to EPEC mixed infection with both, RV (P = 0.045) and NoV (P = 0.188). Shannon diversity index showed considerable more variation in microbiome diversity in children infected with RV cohort compared to NoV cohort. Our results highlight that richness of Bifidobacteriaceae, which acts as probiotics, increased with the severity of the viral-bacterial mixed infections. As expected, significant reduction of relative numbers of Bacteroides was characterized in both RV and NoV infections, with more reduction observed in co-infection pathogenic E. coli. Although mixed infection with EAEC resulted in significant microbiota differences compared to viral infection only or mixed infection with EPEC, the clinical condition of the children were worsened with both pathogenic E.coli co-infections. Further, in comparison with RV cohort, augmented number of differential abundant pathogenic OTUs were peculiarly noticed only with NoV mixed infection.

Prevalence of rotavirus and rapid changes in circulating rotavirus strains among children with acute diarrhea in China, 2009-2015

BACKGROUND

Rotavirus is a leading cause of morbidity and mortality in young children worldwide. In China, the universal immunization of children with the rotavirus vaccine has not been introduced, and the two globally distributed vaccines (RotaTeq and Rotarix) are not licensed in the country. We aim to determine the prevalence and strain diversity of rotavirus in children with diarrhea aged ≤ five years across China.

MATERIALS AND METHODS

Sentinel-based surveillance of acute diarrhea was conducted at 213 participating hospitals in China from January 1, 2009, through December 31, 2015. Group A rotavirus (RVA) was tested by using enzyme-linked immunosorbent assays, and G- and P-genotype of RVA were tested by RT-PCR methods.

RESULTS

Of 33,616 children with diarrhea, 10,089 (30%) were positive for RVA; RVA-associated diarrhea was identified in 2247 (39.5%, n = 2247/5685) inpatients and 7842 (28.1%, n = 7842/27931) outpatients. Children living in low-middle-income regions suffered from the highest burden of rotavirus, with 40.7% of diarrhea cases attributed to rotavirus infection, followed by 31.3% in upper-middle-income and 11.2% in high-income regions. The majority of children (88.9%, n = 8976/10089) who tested positive for RVA were children aged ≤ 2 years. The seasonal peak of RVA was in the winter. Among all 2533 RVA strains genotyped, five strain combinations, G9P[8], G3P[8], G1P[8], G2P[4] and G3P[4], contributed to 71.3% (1807/2533) of the RVA-associated diarrhea cases. The predominant strain of RVA has rapidly evolved from G3P[8] and G1P[8] to G9P[8] in the recent years, with the proportion of G9P[8] having increased remarkably from 3.4% in 2009 to 60.9% in 2015.

CONCLUSIONS

The burden of diarrhea attributed to rotavirus is high in China, highlighting the potential value of vaccination. The rapid shift of RVA strains highlights the importance of conducting rotavirus surveillance to ensure that currently marketed vaccines provide protective efficacy against the circulating strains.

Vaccination herd effect experience in Latin America: a systematic literature review

Background: National pediatric vaccination programs have been introduced in Latin America (LatAm) to reduce the burden of diseases due to pathogens such as rotavirus, Haemophilus influenzae type b (Hib) and pneumococcus. Vaccination health benefits may extend to unvaccinated populations by reducing pathogen transmission. Understanding herd effect is important for implementation and assessment of vaccination programs. The objective was to conduct a systematic review of published epidemiological evidence of herd effect with Hib, rotavirus and pneumococcal conjugate vaccines (PCV) in LatAm.

Methods: Searches were conducted in PubMed, Virtual Health Library (VHL), SciELO and SCOPUS databases, for studies reporting data on herd effect from Hib, rotavirus and PCV vaccination in LatAm, without age restriction. Searches were limited to articles published in English, Spanish or Portuguese (1990–2016). After screening and full-text review, articles meeting the selection criteria were included to be critically appraised following criteria for observational and interventional studies. The presence of a herd effect was defined as a significant decrease in incidence of disease, hospitalization, or mortality.

Results: 3,465 unique articles were identified, and 23 were included (Hib vaccine n = 5, PCV n = 8, rotavirus vaccine n = 10). Most studies included children and/or adolescents (age range varied between studies). Studies in adults, including older adults (aged > 65 years), were limited. Few studies reported statistically significant reductions in disease incidence in age groups not targeted for vaccination. Hib-confirmed meningitis hospitalization decreased in children but herd effect could not be quantified. Some evidence of herd effect was identified for PCV and rotavirus vaccine in unvaccinated children. Evidence for herd effects due to PCV in adults was limited.

Conclusion: After introduction of Hib, PCV and rotavirus vaccination in LatAm, reductions in morbidity/mortality have been reported in children not targeted for vaccination. However, due to methodological limitations (e.g. short post-vaccination periods and age range studied), there is currently insufficient evidence to quantify the herd effect in adult populations. More research and higher quality surveillance is needed to characterize herd effect of these vaccines in LatAm.

Impact of monovalent rotavirus vaccine on diarrhoea-associated post-neonatal infant mortality in rural communities in Malawi: a population-based birth cohort study

BACKGROUND

Rotavirus is a major contributor to child mortality. The effect of rotavirus vaccine on diarrhoea mortality has been estimated in middle-income but not low-income settings, where mortality is high and vaccine effectiveness in reducing admissions to hospital is lower. Empirical population-based mortality studies have not been done in any setting. Malawi introduced monovalent rotavirus vaccine (RV1) in October, 2012. We aimed to investigate the impact and effectiveness of the RV1 vaccine in reducing diarrhoea-associated mortality in infants aged 10-51 weeks.

METHODS

In this population-based cohort study, we included infants born between Jan 1, 2012, and June 1, 2015, in Mchinji, Central Malawi and analysed data on those surviving 10 weeks. Individual vaccination status was extracted from caregiver-held records or report at home visits at 4 months and 1 year of age. Survival to 1 year was confirmed at home visit, or cause of death ascertained by verbal autopsy. We assessed impact (1 minus mortality rate ratio following vs before vaccine introduction) using Poisson regression. Among vaccine-eligible infants (born from Sept 17, 2012), we assessed effectiveness (1 minus hazard ratio) using Cox regression.

FINDINGS

Between Jan 1, 2012, and June 1, 2015, we recruited 48 672 livebirths in Mchinji, among whom 38 518 were vaccine-eligible and 37 570 survived to age 10 weeks. Two-dose versus zero-dose effectiveness analysis included 28 141 infants, of whom 101 had diarrhoea-associated death before 1 year of age. Diarrhoea-associated mortality declined by 31% (95% CI 1-52; p=0·04) after RV1 introduction. Effectiveness against diarrhoea-mortality was 34% (95% CI -28 to 66; p=0·22).

INTERPRETATION

RV1 was associated with substantial reduction in diarrhoea-associated deaths among infants in this rural sub-Saharan African setting. These data add considerable weight to evidence showing the impact of rotavirus vaccine programmes.

FUNDING

Wellcome Trust and GlaxoSmithKline Biologicals.

Viral gastroenteritis

Enteric viruses, particularly rotaviruses and noroviruses, are a leading cause of gastroenteritis worldwide. Rotaviruses primarily affect young children, accounting for almost 40% of hospital admissions for diarrhoea and 200 000 deaths worldwide, with the majority of deaths occurring in developing countries. Two vaccines against rotavirus were licensed in 2006 and have been implemented in 95 countries as of April, 2018. Data from eight high-income and middle-income countries showed a 49-89% decline in rotavirus-associated hospital admissions and a 17-55% decline in all-cause gastroenteritis-associated hospital admissions among children younger than 5 years, within 2 years of vaccine introduction. Noroviruses affect people of all ages, and are a leading cause of foodborne disease and outbreaks of gastroenteritis worldwide. Prevention of norovirus infection relies on frequent hand hygiene, limiting contact with people who are infected with the virus, and disinfection of contaminated environmental surfaces. Norovirus vaccine candidates are in clinical trials; whether vaccines will provide durable protection against the range of genetically and antigenically diverse norovirus strains remains unknown. Treatment of viral gastroenteritis is based primarily on replacement of fluid and electrolytes.

Rotavirus Vaccines: Effectiveness, Safety, and Future Directions

Rotavirus is the leading cause of diarrheal death among children < 5 years old worldwide, estimated to have caused ~ 215,000 deaths in 2013. Prior to rotavirus vaccine implementation, > 65% of children had at least one rotavirus diarrhea illness by 5 years of age and rotavirus accounted for > 40% of all-cause diarrhea hospitalizations globally. Two live, oral rotavirus vaccines have been implemented nationally in > 100 countries since 2006 and their use has substantially reduced the burden of severe diarrheal illness in all settings. Vaccine efficacy and effectiveness estimates suggest there is a gradient in vaccine performance between low child-mortality countries (> 90%) and medium and high child-mortality countries (57-75%). Additionally, an increased risk of intussusception (~ 1-6 per 100,000 vaccinated infants) following vaccination has been documented in some countries, but this is outweighed by the large benefits of vaccination. Two additional live, oral rotavirus vaccines were recently licensed and these have improved on some programmatic limitations of earlier vaccines, such as heat stability, cost, and cold-chain footprint. Non-replicating rotavirus vaccines that are parenterally administered are in clinical testing, and these have the potential to reduce the performance differential and safety concerns associated with live oral rotavirus vaccines.

Impact of rotavirus vaccination on rotavirus hospitalisation rates among a resource-limited rural population in Mbita, Western Kenya

OBJECTIVES

A two-dose oral monovalent rotavirus vaccine (RV1) was introduced into the Kenyan National Immunization Program in July 2014. We assessed trends in hospitalisation for rotavirus-specific acute gastroenteritis (AGE) and strain distribution among children <5 years in a rural, resource-limited setting in Kenya before and after the nationwide implementation of the vaccine.

METHODS

Data on rotavirus AGE and strain distribution were derived from a 5-year hospital-based surveillance. We compared rotavirus-related hospitalisations and strain distribution in the 2-year post-vaccine period with the 3-year pre-vaccine baseline. Vaccine administrative data from the Unit of Vaccines and Immunization Services (UVIS) for Mbita sub-county were used to estimate rotavirus immunisation coverage in the study area.

RESULTS

We observed a 48% (95% CI: 27-64%) overall decline in rotavirus-related hospitalisations among children aged <5 years in the post-vaccine period. Coverage with the last dose of rotavirus vaccine increased from 51% in year 1% to 72% in year 2 of the vaccine implementation. Concurrently, reductions in rotavirus hospitalisations increased from 40% in the first year to 53% in the second year of vaccine use. The reductions were most pronounced among the vaccine-eligible group, with the proportion of cases in this age group dropping to 14% in post-vaccine years from a high of 51% in the pre-vaccine period. A diversity of rotavirus strains circulated before the introduction of the vaccine with G1P[8] being the most dominant strain. G2P[4] replaced G1P[8] as the dominant strain after the vaccine was introduced.

CONCLUSIONS

Rotavirus vaccination has resulted in a notable decline in hospital admissions for rotavirus infections in a rural resource-limited population in Kenya. This provides early evidence for continued use of rotavirus vaccines in routine childhood immunisations in Kenya. Our data also underscore the need for expanding coverage on second dose so as to maximise the impact of the vaccine.

Rotavirus is the leading cause of hospitalizations for severe acute gastroenteritis among Afghan children <5 years old

BACKGROUND

Rotavirus gastroenteritis is estimated to cause approximately five thousand deaths annually among Afghan children under 5 years old. Because laboratory confirmation of rotavirus is not routinely performed in clinical settings, assessing the precise burden of disease attributable to severe rotavirus gastroenteritis typically requires active surveillance efforts. This study describes the current burden of pediatric hospitalizations attributable to rotavirus gastroenteritis among Afghan children using surveillance data collected from 2013 to 2015.

METHODS

Rotavirus surveillance was conducted from January 2013 through December 2015 at two of the largest hospitals in the country, Indira Gandhi Children Hospital in Kabul and Herat Regional Hospital. Children between 1 and 60 months of age who were admitted to these hospitals for diarrhea were consented and enrolled. Information on age, gender, and seasonality were collected. Stool specimens were collected and tested by enzyme immunoassay for the presence of rotavirus at the central public health laboratory in Afghanistan.

RESULTS

Overall, 1,413 of 2,737 (52%) of hospitalized children under five years old with diarrhea were rotavirus cases. The overwhelming majority of rotavirus hospitalizations occurred in children younger than two years of age (93%) while 42% of all rotavirus hospitalizations occurred in children between 6 and 11 months of age. Rotavirus transmission occurred year-round.

CONCLUSIONS

Rotavirus is a major cause of severe acute gastroenteritis hospitalizations in young Afghan children, responsible for over half of diarrheal hospitalizations in this population. The Afghanistan Ministry of Public Health has prioritized reducing child mortality by 2020 and is actively working towards the introduction of rotavirus vaccination in Afghan children. These data will be instrumental in understanding the potential impact upon child health that may be achieved through the introduction of rotavirus vaccines in Afghanistan.

Rotavirus Genotypes Circulating in Brazil Before and After the National Rotavirus Vaccine Program: A Review

BACKGROUND

Rotavirus vaccines created the opportunity to control diarrhea in children. We describe the rotavirus genotypes before and after the rotavirus vaccine introduction in Brazil.

METHODS

We reviewed the distribution of rotavirus genotypes in Brazil before and after vaccine introduction by searching publication.

RESULTS

Eighty-six studies reported 6884 (15.2%) rotavirus episodes among 45,305 children. Rotavirus caused 22.4% and 11.6% of cases before and after vaccine introduction. G1P[8], G9P[8] and G2P[4] heterotypic strains were most common before and after vaccine introduction.

CONCLUSIONS

The vaccines may have selected heterotypic strains in this highly vaccinated population.

Evidence of the impact of monovalent rotavirus vaccine on childhood acute gastroenteritis hospitalization in Togo

BACKGROUND

Monovalent rotavirus vaccine (RV1) was introduced in the immunization schedule of Togo in June 2014. We evaluated the impact of rotavirus vaccines on acute gastroenteritis (AGE) and rotavirus-associated hospitalizations in Togolese children.

METHODS

Sentinel surveillance for AGE (defined as ≥3 liquid or semi-liquid stools/24 h lasting <7 days) hospitalizations among children <5 years of age was conducted in two sites in the capital city, Lome. ELISA was used for diagnosis of rotavirus infection in children with AGE. Additionally, review of hospitalization registers was performed at five hospitals to assess trends in AGE hospitalizations among children aged <5 years. For the vaccine impact assessment, pre-rotavirus vaccine introduction (July 2010-June 2014) and post-rotavirus vaccine introduction (July 2014-June 2016) periods were compared for annual changes in proportions of hospitalizations associated with AGE and rotavirus.

RESULTS

During the pre-vaccine period, sentinel surveillance showed that 1017 patients were enrolled and 57% (range, 53-62%) tested positive for rotavirus, declining to 42% (23% reduction) in the first post-vaccine year and to 26% (53% reduction) in the second post-vaccine year; declines were most marked among infants. The patient register review showed that, compared with pre-vaccine rotavirus seasons, declines in hospitalizations due to all-cause AGE during post-vaccine rotavirus seasons were 48% among <1 year age-group in both first and second years following vaccine introduction. Among 1-4 year olds no reduction was noted in the first year and a 19% decline occurred in the second year.

CONCLUSIONS

We report rapid and marked reduction in the number of AGE hospitalizations and the proportion of AGE hospitalizations attributable to rotavirus in the first two years post- RV1 implementation in Togo. It is necessary to monitor long-term vaccine impact on rotavirus disease burden through continued surveillance.

Cost-effectiveness of rotavirus vaccination in Ghana: Examining impacts from 2012 to 2031

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Ghana is currently transitioning away from Gavi support.

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Thus, cost-effectiveness is crucial for improving health system efficiency.

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Rotavirus vaccination brings health and economic benefits to Ghana.

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Rotavirus vaccination is highly cost-effective in Ghana, even Gavi transition.

Background

Diarrhea causes about 10% of all deaths in children under five years globally, with rotavirus causing about 40% of all diarrhea deaths. Ghana introduced rotavirus vaccination as part of routine immunization in 2012 and it has been shown to be effective in reducing disease burden in children under five years. Ghana’s transition from low to lower-middle income status in 2010 implies fewer resources from Gavi as well as other major global financing mechanisms. Ghana will soon bear the full cost of vaccines. The aim of this study was to estimate the health impact, costs and cost-effectiveness of rotavirus vaccination in Ghana from introduction and beyond the Gavi transition.

Methods

The TRIVAC model is used to estimate costs and effects of rotavirus vaccination from 2012 through 2031. Model inputs include demographics, disease burden, health system structure, health care utilization and costs as well as vaccine cost, coverage, and efficacy. Model inputs came from local data, the international literature and expert consultation. Costs were examined from the health system and societal perspectives.

Results

The results show that continued rotavirus vaccination could avert more than 2.2 million cases and 8900 deaths while saving US$6 to US$9 million in costs over a 20-year period. The net cost of vaccination program is approximately US$60 million over the same period. The societal cost per DALY averted is US$238 to US$332 with cost per case averted ranging from US$27 to US$38. The cost per death averted is approximately US$7000.

Conclusion

The analysis shows that continued rotavirus vaccination will be highly cost-effective, even for the period during which Ghana will assume responsibility for purchasing vaccines after transition from Gavi support.

Cause-specific mortality for 249 causes in Brazil and states during 1990-2015: a systematic analysis for the global burden of disease study 2015

Background

Reliable data on cause of death (COD) are fundamental for planning and resource allocation priorities. We used GBD 2015 estimates to examine levels and trends for the leading causes of death in Brazil from 1990 to 2015.

Methods

We describe the main analytical approaches focused on both overall and specific causes of death for Brazil and Brazilian states.

Results

There was an overall improvement in life expectancy at birth from 1990 to 2015, but with important heterogeneity among states. Reduced mortality due to diarrhea, lower respiratory infections, and other infectious diseases contributed the most for increasing life expectancy in most states from the North and Northeast regions. Reduced mortality due to cardiovascular diseases was the highest contributor in the South, Southeast, and Center West regions. However, among men, intentional injuries reduced life expectancy in 17 out of 27 states. Although age-standardized rates due to ischemic heart disease (IHD) and cerebrovascular disease declined over time, these remained the leading CODs in the country and states. In contrast, leading causes of premature mortality changed substantially - e.g., diarrheal diseases moved from 1st to 13th and then the 36th position in 1990, 2005, and 2015, respectively, while violence moved from 7th to 1st and to 2nd. Overall, the total age-standardized years of life lost (YLL) rate was reduced from 1990 to 2015, bringing the burden of premature deaths closer to expected rates given the country’s Socio-demographic Index (SDI). In 1990, IHD, stroke, diarrhea, neonatal preterm birth complications, road injury, and violence had ratios higher than the expected, while in 2015 only violence was higher, overall and in all states, according to the SDI.

Conclusions

A widespread reduction of mortality levels occurred in Brazil from 1990 to 2015, particularly among children under 5 years old. Major shifts in mortality rates took place among communicable, maternal, neonatal, and nutritional disorders. The mortality profile has shifted to older ages with increases in non-communicable diseases as well as premature deaths due to violence. Policymakers should address health interventions accordingly.

Electronic supplementary material

The online version of this article (10.1186/s12963-017-0156-y) contains supplementary material, which is available to authorized users.

Rotavirus vaccination takes seasonal signature of childhood diarrhea back to pre-sanitation era in Brazil

OBJECTIVES

This study aimed to examine the previously unknown long-term spatio-temporal patterns in diarrheal morbidity and mortality across age groups and geography in Brazil under the light of evolving socioeconomic factors and interventions.

METHODS

Nationwide mortality (1979-2014) and hospitalization (1998-2014) data were obtained from the Brazilian Ministry of Health. Analyses of long-term secular trends and seasonality of diarrheal morbidity and mortality were performed in EPIPOI (www.epipoi.info).

RESULTS

For most states, the primary peak in mortality risk among children under 5 years occurred from December-April (summer/early autumn) from 1979-1988. From 2000-2005 (before the 2006 implementation of rotavirus vaccination), the pattern switched to June-October (winter/early spring). By 2007-2014, the peak in mortality shifted back towards summer/early autumn. A similar pattern was observed for hospitalizations. These patterns were particularly apparent in non-equatorial regions of the country. In contrast, the risk of diarrhea-related death among older children (5-19 years) did not demonstrate well-defined seasonality or spatial patterns.

CONCLUSIONS

Rotavirus vaccination policies were associated with a shift in the timing of seasonal peaks in children under 5, reminiscent of the summer diarrhea period common decades prior. Additionally, young children were shown to have distinct disease patterns compared to other age groups, suggesting different etiologies.