Global illness and deaths caused by rotavirus disease in children

The influence of human genetic variation on early transcriptional responses and protective immunity following immunization with Rotarix vaccine in infants in Ho Chi Minh City in Vietnam: A study protocol for an open single-arm interventional trial

Background: Rotavirus (RoV) remains the leading cause of acute gastroenteritis in infants and children aged under five years in both high- and low-middle-income countries (LMICs). In LMICs, RoV infections are associated with substantial mortality. Two RoV vaccines (Rotarix and Rotateq) are widely available for use in infants, both of which have been shown to be highly efficacious in Europe and North America. However, for unknown reasons, these RoV vaccines have markedly lower efficacy in LMICs. We hypothesize that poor RoV vaccine efficacy across in certain regions may be associated with genetic heritability or gene expression in the human host. Methods/design: We designed an open-label single-arm interventional trial with the Rotarix RoV vaccine to identify genetic and transcriptomic markers associated with generating a protective immune response against RoV. Overall, 1,000 infants will be recruited prior to Expanded Program on Immunization (EPI) vaccinations at two months of age and vaccinated with oral Rotarix vaccine at two and three months, after which the infants will be followed-up for diarrheal disease until 18 months of age. Blood sampling for genetics, transcriptomics, and immunological analysis will be conducted before each Rotarix vaccination, 2-3 days post-vaccination, and at each follow-up visit (i.e. 6, 12 and 18 months of age). Stool samples will be collected during each diarrheal episode to identify RoV infection. The primary outcome will be Rotarix vaccine failure events (i.e. symptomatic RoV infection despite vaccination), secondary outcomes will be antibody responses and genotypic characterization of the infection virus in Rotarix failure events. Discussion: This study will be the largest and best powered study of its kind to be conducted to date in infants, and will be critical for our understanding of RoV immunity, human genetics in the Vietnam population, and mechanisms determining RoV vaccine-mediated protection. Registration: ClinicalTrials.gov, ID: NCT03587389. Registered on 16 July 2018.

Norovirus compared to other relevant etiologies of acute gastroenteritis among families from a semirural county in Chile

OBJECTIVE

To determine the dynamics of norovirus disease, a major cause of acute gastroenteritis (AGE), compared to other relevant etiologies, among families living in a lower middle income area.

STUDY DESIGN

Families with three or more members and with one or more healthy children <24 months of age were followed for 1-2 years to detect any AGE. Stool samples were tested for viral and bacterial pathogens and a questionnaire was completed for those with norovirus or rotavirus AGE.

RESULTS

Between April and June 2016, 110 families were enrolled, with 103 of them completing ≥12 months of follow-up. A total of 159 family AGE episodes were detected, mostly affecting one individual (92%). At least one pathogen was detected in 56% (94/169) of samples, of which 75/94 (80%) were sole infections. Norovirus was most common (n=26), followed closely by enteropathogenic Escherichia coli (EPEC) (n=25), rotavirus (n=24), and astrovirus (n=23). The annual incidence of family AGE was 0.77, and 0.12 for norovirus. Most norovirus AGE occurred in children <4 years old (96%). Only 13/159 (8%) index AGE cases resulted in a secondary case, of which four were associated with norovirus. The majority of norovirus strains were GII (85%), with a mild predominance of GII.4 (9/26; 35%); most norovirus isolates (69%) were recombinants.

CONCLUSIONS

The family incidence of AGE in this lower middle income community was nearly one episode per year, mostly caused by viruses, specifically norovirus closely followed by rotavirus and astrovirus. Norovirus infections primarily affected children <4 years old and secondary cases were uncommon.

Effect of nitazoxanide on diarrhea: A systematic review and network meta-analysis of randomized controlled trials

We aimed to systematically review evidence pertaining to the safety and efficacy of nitazoxanide in treating infectious diarrhea. On September 21, 2017, we identified relevant studies using 12 databases. The estimates of the included studies were pooled as a risk ratio (RR). We conducted a network and pairwise random-effects meta-analysis for both direct and indirect comparisons of different organisms that are known to cause diarrhea. The primary and secondary analysis outcomes were clinical response until cessation of illness, parasitological response and adverse events. We included 18 studies in our analysis. In cryptosporidiosis, the overall estimate favored nitazoxanide in its clinical response in comparison with placebo RR 1.46 [95% CI 1.22-1.74; P-value <0.0001]. Network meta-analysis among patients with Giardia intestinalis showed an increase in the probability of diarrheal cessation and parasitological responses in comparison with placebo, RR 1.69 [95% CI 1.08-2.64, P-score 0.27] and RR 2.91 [95% CI 1.72-4.91, P-score 0.55] respectively. In Clostridium difficile infection, the network meta-analysis revealed a non-significantly superior clinical response effect of nitazoxanide to metronidazole 31 days after treatment RR 1.21 [95% CI 0.87-1.69, P-score 0.26]. In Entamoeba histolytica, the overall estimate significantly favored nitazoxanide in parasitological response with placebo RR 1.80 [95% CI 1.35-2.40, P-value < 0.001]. We highlighted the effectiveness of nitazoxanide in the cessation of diarrhea caused by Cryptosporidium, Giardia intestinalis and Entamoeba histolytica infection. We also found significant superiority of NTZ to metronidazole in improving the clinical response to G. intestinalis, thus it may be a suitable candidate for treating infection-induced diarrhea. To prove the superiority of NTZ during a C. difficile infection may warrant a larger-scale clinical trial since its superiority was deemed insignificant. We recommend nitazoxanide as an appropriate option for treating infectious diarrhea.

Group A Rotavirus G1P[6] Associated Fatalities in Diarrheic Nigerian Infants, Possible Impact of Enterovirus Environmental Enteric Dysfunction, and Implications for Rota-Vaccinology

Group A rotavirus (RVA) diarrhea disease and mortality are yet unabated, particularly in developing countries. As global knowledge of specific strains associated with infant mortality is crucial for successful vaccination efforts, candidate RVA strains detected in mortality and fatal cases of severely diarrheic hospitalized infants in Akure, Nigeria were investigated.

Fecal samples from comatose patients were tested for RVAs, other diarrhea viruses, and enteric bacterial pathogens. Genomic dsRNA was extracted from 10% rotavirus positive stool suspension, the VP4 and VP7 genes were reverse transcribed and amplified by one-step reverse transcription polymerase chain reaction (PCR) and genotyped by seminested multiplex PCR. Amplicons were sequenced, aligned by ClustalW, and phylogenetic analyses were conducted in MEGA6. Sequences data were deposited to GenBank and DDBJ.

Medical examination and microbiological analyses upheld viral diarrhea. EIA revealed RVA and enterovirus. PCR identified virulent RVA strain GIP[6] whose VP7 nucleotide sequences shared a common cluster with Cuban isolate G1P[6], while the VP4 P[6] sequences were related to Asian strains. Reassortant RVA G1P[6] was found in fatal diarrhea cases and mortality of a Nigerian child. RVA coinfection with enterovirus and associated biomarkers of environmental enteric dysfunction in infantile diarrhea should henceforth be evaluated. Current rotavirus vaccines may fare badly against the prevailing virulent strains. The disease severity and outcome necessitates a wider epidemiological study, a review and inclusion of the P[6] genotype in future rotavirus vaccines.

Effect of a new Lactobacillus plantarum product, LRCC5310, on clinical symptoms and virus reduction in children with rotaviral enteritis

BACKGROUND

Rotavirus is one of the most common causes of infantile enteritis. In common enterocolitis, probiotic organisms, including Lactobacilli, are effective in treating diarrhea. A new species, Lactobacillus plantarum (LRCC5310), which was shown to inhibit the adherence and proliferation of rotavirus in the small intestine through animal experiments, was investigated for the efficacy and safety of patients with rotaviral enteritis.

METHODS

LRCC5310 (Group I) and control (Group II) groups consisting of children who were hospitalized for rotaviral enteritis were compared, and the medical records of patients (Group III) who were hospitalized for rotaviral enteritis during the same study period were retrospectively analyzed. Clinical symptoms were compared and stool samples were collected to compare changes in virus multiplication between Groups I and II.

RESULTS

Groups I, II, and III comprised 15, 8, and 27 children, respectively. There were no differences in clinical information among the groups at admission. In Group I, a statistically significant improvement was noted in the number of patients with diarrhea, number of defecation events on Day 3, and total diarrhea period as opposed to Group II (P = .033, P = .003, and P = .012, respectively). The improvement of Vesikari score in Group I was greater than that in the other groups (P = .076, P = .061, and P = .036, respectively). Among rotavirus genotypes, 9 (22.5%) strains and 8 (20.0%) strains belonged to the G9P8 and G1P8 genotypes, respectively. The virus reduction effect, as confirmed via stool specimens, was also greater in Group I. No significant side effects were noted in infants.

CONCLUSION

LRCC5310 improved clinical symptoms, including diarrhea and Vesikari score, and inhibited viral proliferation in rotaviral gastroenteritis.

Referral rates for children with acute gastroenteritis: a retrospective cohort study

Background

Hospital admission rates are increasing for children with acute gastroenteritis. However, it is unknown whether this increase is accompanied by an increase in referral rates from GPs due to increased workloads in primary care out-of-hours (OOH) services.

Aim

To assess trends in referral rates from primary care OOH services to specialist emergency care for children presenting with acute gastroenteritis.

Design & setting

This retrospective cohort study covered a period from September 2007–September 2014. Children aged 6 months to 6 years presenting with acute gastroenteritis to a primary care OOH service were included.

Method

Pseudonymised data were obtained, and children were analysed overall and by age category. Χ² trend tests were used to assess rates of acute gastroenteritis, referrals, face-to-face contacts, and oral rehydration therapy (ORT) prescriptions.

Results

The data included 12 455 children (6517 boys), with a median age of 20.2 months (interquartile range [IQR] 11.6 to 36.0 months). Over 7 years, incidence rates of acute gastroenteritis decreased significantly, and face-to-face contact rates increased significantly (both, P<0.01). However, there was no significant trend for referral rates (P = 0.87) or prescription rates for ORT (P = 0.82). Subgroup analyses produced comparable results, although there was an increase in face-to-face contact rates for the older children.

Conclusion

Incidence rates for childhood acute gastroenteritis presenting in OOH services decreased and referral rates did not increase significantly. These findings may be useful as a reference for the impact of new interventions for childhood acute gastroenteritis.

Genotypic determination of human group A rotaviruses from Goa and Meghalaya states, India

Introduction

Rotavirus is the leading cause of diarrhoea in young children in India, responsible for an estimated 21357 mean numbers of deaths in 2010. Various genotypes of rotaviruses evolved due to mutational changes have been recognized. In this study, we determined the genotypes of rotaviruses involved in diarrhea in Goa and Meghalaya states of India.

Methods

The dsRNA of rotaviruses was extracted from stool samples and detected by Ribonucleic Acid-Polyacrylamide gel electrophoresis (RNA PAGE) and Reverse transcription-polymerase Chain Reaction (RT-PCR) targeting the partial VP7 gene. The full length VP7 and partial VP4 genes of rotavirus strains were amplified by RT-PCR followed by nucleotide sequencing. The RotaC classification tool was used to determine the genotypes.

Results

The positivity of rotavirus by PAGE and RT-PCR was observed to be 43.10% and 39.65% in Goa and 38% and 36% in Meghalaya, respectively. Though long electrophoretic profile was appeared to be the most predominant rotavirus type in circulation in these two states, 96% of long and 84.61% short electropherotype profiles could be detected by RT-PCR. The dsRNA of rotavirus extracted from 36 samples could be transcribed and amplified by beg9end9 primers for G genotyping, while, 41 by con3con2 primers for P genotyping. G1P[8] and G1P[6] genotypes were commonly circulated in Goa and G1P[8] and G1P[4] genotypes in Meghalaya. On nucleotide analysis, 6 samples from Goa showed G1 genotype specificity, while, 3 showed P[8] specificity indicating the G1P[8] rotavirus circulating in Goa. In Meghalaya state, 3 strains showed P[8] and 2 showed P[4] genotype specificity. The majority of the G and P genotypes were closely related to each other and G1 genotypes appeared in two separate clusters, while, P[8] and P[4] appeared in the respective clusters.

Conclusion

The circulation of G1P[8], G1P[6] genotypes in Goa and the presence of G1P[8] and G1P[4] genotypes in Meghalaya was observed.

Enteric Viral Co-Infections: Pathogenesis and Perspective

Enteric viral co-infections, infections involving more than one virus, have been reported for a diverse group of etiological agents, including rotavirus, norovirus, astrovirus, adenovirus, and enteroviruses. These pathogens are causative agents for acute gastroenteritis and diarrheal disease in immunocompetent and immunocompromised individuals of all ages globally. Despite virus–virus co-infection events in the intestine being increasingly detected, little is known about their impact on disease outcomes or human health. Here, we review what is currently known about the clinical prevalence of virus–virus co-infections and how co-infections may influence vaccine responses. While experimental investigations into enteric virus co-infections have been limited, we highlight in vivo and in vitro models with exciting potential to investigate viral co-infections. Many features of virus–virus co-infection mechanisms in the intestine remain unclear, and further research will be critical.

May rotavirus vaccine be affect food allergy prevalence?

Incidence of food allergy (FA) during nursing period is 6–8% globally and It is reported %5,7 in Turkey. In our study, the aim is to determine whether the prevalence of food allergy (FA) increases in children vaccinated against rotavirus. The files of 681 infants who are still followed-up were retrospectively evaluated. Children who did not come to our clinic for all of their well-child follow-up visits were excluded from the study. Moreover, children diagnosed with allergy before vaccination and children with known gastrointestinal system disease were excluded from the study. The number of patients diagnosed with food allergy after being vaccinated against rotavirus was 12 (1.76%). Three children had a family history of allergy. Of 12 patients who were diagnosed after vaccination, 3 (n:104) were vaccinated with pentavalent vaccine and 9 (n:507) with monovalent vaccine. In the monovalent vaccination group, food allergy was found in 9 children (1.55%), and in the pentavalent vaccination group, food allergy was found in 3 children (2.88%). The difference between the two vaccination groups in terms of food allergy prevalence was not significant (p > .05). Although it is believed that food allergy, and even cow’s milk protein allergy (CMPA) prevalence increases in infants vaccinated against rotavirus, in this study, no significant increase was observed in the prevalence of food allergy after rotavirus vaccination. Both types of vaccine had similar rates to each other.

Accounting for indirect protection in the benefit-risk ratio estimation of rotavirus vaccination in children under the age of 5 years, France, 2018

Background Rotavirus is a major cause of severe gastroenteritis in children worldwide. The disease burden has been substantially reduced in countries where rotavirus vaccines are used. Given the risk of vaccine-induced intussusception, the benefit–risk balance of rotavirus vaccination has been assessed in several countries, however mostly without considering indirect protection effects. Aim We performed a benefit–risk analysis of rotavirus vaccination accounting for indirect protection in France among the 2018 population of children under the age of 5 years. Methods To incorporate indirect protection effects in the benefit formula, we adopted a pseudo-vaccine approach involving mathematical approximation and used a simulation design to provide uncertainty intervals. We derived background incidence distributions from quasi-exhaustive health claim data. We examined different coverage levels and assumptions regarding the waning effects and intussusception case fatality rate. Results With the current vaccination coverage of < 10%, the indirect effectiveness was estimated at 6.4% (+/− 0.4). For each hospitalisation for intussusception, 277.0 (95% uncertainty interval: (165.0–462.1)) hospitalisations for rotavirus gastroenteritis were prevented. Should 90% of infants be vaccinated, indirect effectiveness would reach 57.9% (+/− 3.7) and the benefit–risk ratio would be 192.4 (95% uncertainty interval: 116.4–321.3). At a coverage level of 50%, indirect protection accounted for 27% of the prevented rotavirus gastroenteritis cases. The balance remained in favour of the vaccine even in a scenario with a high assumption for intussusception case fatality. Conclusions These findings contribute to a better assessment of the rotavirus vaccine benefit–risk balance.

Prevalence and diversity of human rotavirus among Thai adults

Rotavirus infections have become one of the most common causes of infectious gastroenteritis in children. Although rotavirus infections have been intensively studied in infants and young children, the study in adults has been limited. As such, this study assessed the prevalence of rotaviruses and performed the molecular characterization of rotaviruses circulating in Thai adults experiencing acute gastroenteritis between January 2018 and December 2018. Group A human rotaviruses were detected in 100 feces samples by rapid immunochromatography. The peak incidence of infection occurred in February and began to decline in the summer months. From January 2018 to December 2018, there were 1344 acute gastroenteritis adult cases in the Hospital for Tropical Diseases, Bangkok, Thailand. Among these, 310 cases were rotavirus-suspected cases. Only 100 samples tested positive for rotavirus via an immunochromatography test. Twentynine out of the 100 rotavirus-positive samples were further characterized by real-time polymerase chain reaction. The G3[P8] strain was identified as the most prevalent (31.0%) followed by G1P[8], G8P[8] and G9P[8], and G2P[8], which accounted for 20.8%, 17.2%, and 13.8%, respectively. Because of the detection of rare rotavirus genotypes, such as G8, the surveillance of rotavirus epidemiology is crucial in monitoring new emergences of rotavirus strains, leading to a better understanding of the effects of strain variation for further vaccine development.

Prevalence, risk factors, and clinical characteristics of rotavirus and adenovirus among Lebanese hospitalized children with acute gastroenteritis

BACKGROUND

Acute gastroenteritis is a very common infectious disease facing all age groups worldwide, especially the pediatric population. Viruses, bacteria, and parasites are all possible causes of infectious gastroenteritis; however, viruses have become more frequently identified with the advances in the ability to diagnose viral infections, particularly rotavirus and adenovirus. We aimed in our study to compare between the prevalence, risk factors, and clinical characteristics of rotavirus and adenovirus among children with viral gastroenteritis in Lebanon.

MATERIALS AND METHODS

A 12-months retrospective study was performed between January 1st and December 31st, 2018 including 308 children aged 1 month to 12 years, who were admitted to three tertiary healthcare centers in South Lebanon. Medical data were retrieved from patients' files, including clinical and laboratory information.

RESULTS

Rotavirus was found in stool of 204 patients (66.23 %), followed by adenovirus in 78 cases (25.32 %), and mixed group (rotavirus and adenovirus) in 26 cases (8.44%). The highest prevalence of rotavirus in our present study was seen among children between 12 and 23 months old, whereas patients infected with adenovirus were mainly aged between 24-35 months or 4-11 months. Majority of patients in the adenovirus and mixed groups had high-grade fever compared to the rotavirus group. Laboratory findings presented significantly higher average of white blood cells (WBCs), absolute neutrophil count (ANC), and C-reactive protein (CRP) in the mixed group compared to the two other groups. Monthly distribution of rotavirus and adenovirus infection revealed a biennial pattern of rotavirus incidence during January and July-August while frequency of adenovirus infection was highest during July-August.

CONCLUSION

Due to the high prevalence of viral diarrhea among the pediatric age group in our region, particularly rotavirus and adenovirus, along with the associated non-specific signs and symptoms, we highly recommend that medical laboratories be equipped for virus detection. Also, vaccination against rotavirus should be considered as a prevention strategy.

Socioeconomic Impact of the Rotavirus Vaccine in Korea: Comparing the Epidemiologic and Economic Characteristics of Rotavirus Gastroenteritis Before and After the Introduction of Vaccines

BACKGROUND

Since the introduction of 2 rotavirus (RV) vaccines in Korea, the vaccination rate has reached over 80% with out-of-pocket spending in the private market. We investigated the socioeconomic impact of RV vaccines in Korea to assess their value and public health contribution.

METHODS

By using National Health Insurance Service claims data, we compared the epidemiologic and economic characteristics of rotavirus gastroenteritis (RVGE) before and after the introduction of RV vaccines. For each year of the study period, the annual prevalence and national costs of RVGE were estimated based on children under 5 years with at least 1 National Health Insurance Service claims record with a diagnosis of RVGE.

RESULTS

Compared with the prevaccination period, the prevalence of RVGE decreased in the postvaccination period by 48.9% from 2097 per 100,000 children in 2006 to 1072 per 100,000 children in 2015, implying an increase in the vaccination rate and the prevention effect of the vaccines. The highest reduction was observed among those 12 to <24 months of age (-73.4%), presumably due to the benefit of full vaccination, while children under 2 months, ineligible for the RV vaccine, showed an increase (41.7%). The number of hospitalized RVGE cases per year decreased by 69.0%. The national economic burden of RVGE decreased by 28.6%.

CONCLUSIONS

The substantial reduction in the socioeconomic burden of RVGE after the introduction of RV vaccines confirms their benefit to society. This study would help health policy makers make empirical decisions on incorporating the vaccination into national immunization programs.

Rotavirus and autoimmunity

Rotavirus, a major etiological agent of acute diarrhea in children worldwide, has historically been linked to autoimmunity. In the last few years, several physiopathological approaches have been proposed to explain the leading mechanism triggering autoimmunity, from the old concept of molecular mimicry to the emerging theory of bystander activation and break of tolerance. Epidemiological and immunological data indicate a strong link between rotavirus infection and two of the autoimmune pathologies with the highest incidence: celiac disease and diabetes. The role for current oral rotavirus vaccines is now being elucidated, with a so far positive protective association demonstrated.

Probiotic mixture VSL#3: An overview of basic and clinical studies in chronic diseases

Probiotics are known as “live microorganisms” and have been proven to have a health effect on hosts at the proper dose. Recently, a kind of probiotic mixture including eight live bacterial strains, VSL#3, has attracted considerable attention for its combined effect. VSL#3 is the only probiotic considered as a kind of medical food; it mainly participates in the regulation of the intestinal barrier function, including improving tight junction protein function, balancing intestinal microbial composition, regulating immune-related cytokine expression and so on. The objective of this review is to discuss the treatment action and mechanism for the administration of VSL#3 in chronic diseases of animals and humans (including children). We found that VSL#3 has a therapeutic or preventive effect in various systemic diseases per a large number of studies, including digestive systemic diseases (gastrointestinal diseases and hepatic diseases), obesity and diabetes, allergic diseases, nervous systemic diseases, atherosclerosis, bone diseases, and female reproductive systemic diseases.

Amino Acid Substitutions in Positions 385 and 393 of the Hydrophobic Region of VP4 May Be Associated with Rotavirus Attenuation and Cell Culture Adaptation

Rotaviruses (RVs) are the leading cause of the acute viral gastroenteritis in young children and livestock animals worldwide. Although live attenuated vaccines have been applied to control RV infection for many years, the underlying mechanisms of RV attenuation following cell culture adaption are unknown. To study these mechanisms at the genomic level, we have sequenced and conducted a comparative analysis of two virulent human (Wa, G1P[8] and M, G3P[8]) and two virulent porcine (Gottfried, G4P[6] and OSU, G5P[7]) RV strains maintained in gnotobiotic piglets for 22, 11, 12 and 9 serial passages, respectively, with their attenuated counterparts serially passaged in MA-104 cell cultures for 25, 43, 54 and 43 passages, respectively. We showed that most of the mutations were clustered in the VP4 gene, with a relatively high nonsynonymous substitution rate (81.2%). Moreover, two amino acid substitutions observed in the VP4 gene were conserved between two or more strain pairs. D385N substitution was found in M, Wa and Gottfried strains, and another one, S471H/L was present in Wa and Gottfried strains. Importantly, D385 was reported previously in another study and may be involved in regulation of virus entry. Of interest, although no 385 substitution was found in OSU strains, the attenuated OSU strain contained a unique D393H substitution within the same VP4 hydrophobic domain. Collectively, our data suggest that the VP4 hydrophobic region may play an important role in RV attenuation and aa385 and aa393 may represent potential targets for RV vaccine development using reverse genetics and site-specific mutagenesis.

Characterization of a G9 group A rotavirus reassortant strain detected in Jinzhou, China, in 2018-2019

A novel rotavirus A (RVA) strain (JZ) was detected in RVA-positive stool specimens from three pediatric patients in Jinzhou, Liaoning Province, in 2018-2019. The electrophoresis pattern of the JZ strain showed a long electropherotype. The genomic constellation G9-P[8]-I1-R1-C1-M1-A1-N1-T1-E2-H1 was detected, suggesting that a new inter-genogroup reassortment had occurred. Whole-genome sequencing showed that the JZ isolates were identical to each other. Phylogenetic analysis revealed that VP7 and VP4 clustered in lineages G9-VI and P[8]-3, respectively. JZ strain-specific amino acid substitutions were detected in VP7, VP4 and NSP4. This study provides information on the epidemiology and characteristics of G9 strains circulating in China.

Genetic Diversity of Human Rotavirus A Among Hospitalized Children Under-5 Years in Lebanon

Human rotavirus remains a major cause of gastroenteritis worldwide despite the availability of effective vaccines. In this study, we investigated the genetic diversity of rotaviruses circulating in Lebanon. We genetically characterized the VP4 and VP7 genes encoding the outer capsid proteins of 132 rotavirus-associated gastroenteritis specimens, previously identified in hospitalized children (<5 years) from 2011 to 2013 in Lebanon. These included 43 vaccine-breakthrough specimens and the remainder were from non-vaccinated subjects. Phylogenetic analysis of VP4 and VP7 genes revealed distinct clustering compared to the vaccine strains, and several substitutions were identified in the antigenic epitopes of Lebanese specimens. No unique changes were identified in the breakthrough specimens compared to non-breakthroughs that could explain the occurrence of infection in vaccinated children. Further, we report the emergence of a rare P[8] OP354-like strain with a G9 VP7 in Lebanon, possessing high genetic variability in their VP4 compared to vaccine strains. Therefore, human rotavirus strains circulating in Lebanon and globally have accumulated numerous substitutions in their antigenic sites compared to those currently used in the licensed vaccines. The successful spread and continued genetic drift of these strains over time might undermine the effectiveness of the vaccines. The effect of such changes in the antigenic sites on vaccine efficacy remains to be assessed.

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

INTRODUCTION

The Palestinian Ministry of Health (MOH) started a routine rotavirus immunization program with ROTARIX in May 2016, with support for vaccine procurement and introduction provided through a global development organization. In 2018, financial responsibility for rotavirus vaccine procurement was transferred to the Palestinian government, which elected to shift to ROTAVAC vaccine because of its lower price per dose. This study aims to assess the cost, impact, and cost-effectiveness of rotavirus vaccination, specifically evaluating the economic implications of the change in vaccine product, accounting for the different characteristics of each rotavirus vaccine used.

METHODS

We conducted primary and secondary data collection to assess the introduction, procurement, supply chain, and service delivery costs related to each vaccine. We used the UNIVAC model to project costs and benefits of rotavirus vaccination over a 10-year period comparing the use of ROTARIX versus no vaccination; ROTAVAC versus no vaccination; and ROTAVAC versus ROTARIX. We undertook scenario and probabilistic analyses to capture uncertainty in some of the study parameters. We used a 3% discount rate, and all costs are in 2018 US$.

RESULTS

The cost to deliver one dose was lower for ROTAVAC than ROTARIX (US$2.36 versus $2.70), but the total cost per course, excluding vaccine cost, favored ROTARIX ($7.09 versus $5.39). Both vaccines had high probability of being cost-effective interventions in Palestine compared to no vaccine. Because of lower vaccination program costs for ROTAVAC, however, switching from ROTARIX to ROTAVAC was cost-saving.

CONCLUSION

National decision-makers should consider systematically assessing multiple criteria beyond vaccine price when comparing the health and economic value of several products in order to fully account for all characteristics including product presentation, number of doses per course, cold chain volume, cost of delivery, and wastage.

Analysis of viral diversity in stool samples from infants and children with acute gastroenteritis in Kuwait using Metagenomics approach

Background

Current molecular target-dependent methods are used to detect only known viruses. However, metagenomics based on next-generation sequencing (NGS) technique is a target-independent assay that enables simultaneous detection and genomic characterisation of all microorganisms present in a sample. In this study, we aimed to develop a metagenomics approach using NGS to identify and characterise viruses in stool samples from infants and children with Acute Gastroenteritis (AGE) in Kuwait.

Methods

We have investigated 84 stool samples from infants and children aged one month to ten years old with signs and symptoms of gastroenteritis who attended Mubarak Al-Kabeer and Al-Amiri hospitals in Kuwait from January to December 2017. A metagenomics approach using NGS to characterise viruses in clinical samples was used. Also, the commercial Real-Time PCR assay was used to detect viruses causing gastroenteritis.

Results

Metagenomics analysis revealed an average of 280,768 reads in which 5% of the reads were derived from viruses. The analysis of viral sequences verified that single infection of human adenovirus was the leading cause of gastroenteritis among infants and children, which was detected in 23.2% of the patients, followed by a mixed infection of human adenovirus and other viruses, which was detected in 20.9% of patients. Also, the newly discovered viruses known to cause gastroenteritis were detected, such as astrovirus MLB2, primate bocaparvovirus-1, Aichivirus A, cardiovirus, parechovirus A, astrovirus VA4, cosavirus-F, and bufavirus-3. Our results showed 71% agreement (k = 0.445, P = 0.000) between multiplex Real-Time PCR, which is used as a routine diagnostic test and metagenomics approach in the detection of viruses causing gastroenteritis in clinical samples.

Conclusion

Despite the difficulties in sample preparation and analysis process, we showed that metagenomics approach is a powerful and promising tool for the detection and characterisation of different viruses in clinical samples.

First report of Cryptosporidium hominis in a freshwater sponge

Identification of Cryptosporidium oocyst is essential in ensuring water quality fit for human use, consumption, and recreation. This communication proposes the supplemental analysis of substrate-associated biofilms, in particular, freshwater sponges in improving case finding of waterborne-protozoan pathogens (WBPP) in environmental aquatic samples. In this study, a small portion of a mature freshwater sponge under the Genus Spongilla was subjected to microscopic and molecular analysis to identify the presence of Cryptosporidium. Microscopic screening with modified Kinyoun's staining (MK) and microscopic confirmation using direct antibody fluorescent testing (IFT) returned with Cryptosporidium spp. positive findings. Molecular investigation resulted in the confirmation of Cryptosporidium hominis upon sequencing of PCR products and phylogenetic analysis. This is the first report of a pathogenic protozoan, C. hominis isolated from a freshwater sponge. The results of this study provide evidence of the value of expanding water quality assessment strategies to the analysis of substrate-associated biofilms and sponges in improving case finding of WBPP in natural aquatic environments.

Waterborne Transmission of Enteric Viruses and Their Impact on Public Health

Viruses of human or animal origin can spread in the environment and infect people via water and food. These viruses are released into the environment by various routes including water runoffs and aerosols. Furthermore, zoonotic viruses may infect humans exposed to contaminated surface waters.

Viruses are emerging pathogens and are able to adapt by mutation, recombination, and reassortment and can thus become able to infect new hosts and to adjust to new environments. Enteric viruses are among the commonest and most hazardous waterborne pathogens, causing both sporadic and outbreak-related illness.

While considerable research has documented the risk of enteric viruses to human health from contact with contaminated water, the current bacterial indicator-based methods for the evaluation of water quality are often ineffectual proxies for pathogenic viruses, but no correlation was established between the enteric bacteria and viruses studied.

The present chapter will focus on viral pathogens shown to be transmitted through water. It will also provide an overview of viruses that had not been a concern for waterborne transmission in the past, but that may represent potentially emerging waterborne pathogens due to their occurrence and persistence in water environments.

Monitoring effluents from wastewater treatment plants is important to preventing both environmental contamination and the spread of disease.

The effect of the waste disposal crisis on the rates of hospitalization due to acute diarrheal illness in a middle-income country: Retrospective chart review

BACKGROUND

A waste disposal crisis occurred in Lebanon leading to the accumulation of garbage in the streets of Beirut. It is not clear whether such a limited crisis of improper waste disposal will lead to more diarrhea illnesses. The purpose of this study is to compare the rates of admissions due to diarrhea and characterize the illness among adults and children before, during and after the garbage crisis.

MATERIALS AND METHODS

This study is an observational retrospective in-patient chart review extending over four time intervals: pre-crisis, major crisis, minor crisis, and post-crisis periods. Hospital admissions due to diarrhea or gastroenteritis were included. Descriptive analysis of the following was done: characteristics of the present illness at the time of admission, stool and lab tests ordered and management of the diarrhea illness.

RESULTS

There was an increase in admission rates due to diarrhea in the months of the crisis as compared to pre and post-crisis months. The severity of diarrheal illness and the management of admitted patients were almost the same across the four periods. Rota virus diarrheal outbreak was noted during the major crisis among children less than 2 years old, and adults above 18 years old.

CONCLUSIONS

Despite an increase in the rates of admissions due to diarrhea during the garbage crisis, the severity of the diarrhea illness did not differ. This may indicate that physicians and patients were more worried and utilized more health services. However, Rota outbreaks may be more prominent with improper garbage disposal.

Racecadotril for acute diarrhoea in children

BACKGROUND

Acute diarrhoea is a leading cause of death for children under five years of age. Most deaths are caused by excessive fluid and electrolyte losses. Racecadotril is an anti-secretory drug that has been used for acute diarrhoea in children as an adjunct to oral rehydration therapy.

OBJECTIVES

To assess the efficacy and safety of racecadotril for treating acute diarrhoea in children under five years of age.

SEARCH METHODS

We searched the Cochrane Infectious Diseases Group Specialized Register; the Cochrane Central Register of Controlled Trials (CENTRAL, published in the Cochrane Library Issue 3, March 2019); MEDLINE; Embase; LILACS; ClinicalTrials.gov; and the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP), up to 4 March 2019, for clinical trials regardless of publication language or status.

SELECTION CRITERIA

Randomized controlled trials (RCTs) that compared racecadotril to placebo or no intervention in addition to standard care (oral rehydration therapy) in children under five with acute diarrhoea. The primary outcomes were failure of oral rehydration, duration of diarrhoea, and number of stools. The secondary outcomes were stool output, length of the hospital stay, and adverse events.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial eligibility, extracted the data and assessed risk of bias. We presented dichotomous data with risk ratios (RR) and continuous data with mean difference (MD) or standardized mean difference (SMD). Where appropriate, we combined trials with meta-analysis and used a random-effects model if there was significant heterogeneity (I² ≥ 50%). We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

Seven RCTs with a total of 1140 participants met the inclusion criteria. The trials were carried out on children aged three months to five years, in outpatient and inpatient facilities from France, Spain, Peru, India, Kenya, and Ecuador. The efficacy and safety of racecadotril were compared to placebo or no treatment. Racecadotril may reduce the risk of rehydration failure (RR 0.41, 95% CI 0.13 to 1.23; 2 RCTs, 192 participants; low-certainty evidence). Data on duration of diarrhoea, number of stools in the first 48 hours are insufficient to reach a conclusion; stool output in the first 48 hours appears to be lower in the two trials measuring this, although the data is not combinable. Length of hospital stay was similar in two studies measuring this, and overall there was no evidence that racecadotril increased overall rate of adverse events (RR 0.90, 95% CI 0.66 to 1.22; 5 RCTs, 688 participants; low-certainty evidence). Most adverse events in the racecadotril group were mild or moderate.

AUTHORS' CONCLUSIONS

Racecadotril seems to be a safe drug but has little benefit in improving acute diarrhoea in children under five years of age. Current evidence does not support routine use of racecadotril in management of acute diarrhoea in children under five outside of the context of placebo controlled RCTs. 18 December 2019 Up to date All studies incorporated from most recent search All studies identified during the most recent search (4 Mar, 2019) have been incorporated in the review, and no ongoing studies identified.

Recombinant Rotaviruses Rescued by Reverse Genetics Reveal the Role of NSP5 Hyperphosphorylation in the Assembly of Viral Factories

The rotavirus (RV) double-stranded RNA genome is replicated and packaged into virus progeny in cytoplasmic structures termed viroplasms. The nonstructural protein NSP5, which undergoes a complex hyperphosphorylation process during RV infection, is required for the formation of these virus-induced organelles. However, its roles in viroplasm formation and RV replication have never been directly assessed due to the lack of a fully tractable reverse-genetics (RG) system for rotaviruses. Here, we show a novel application of a recently developed RG system by establishing a stable trans-complementing NSP5-producing cell line required to rescue rotaviruses with mutations in NSP5. This approach allowed us to provide the first direct evidence of the pivotal role of this protein during RV replication. Furthermore, using recombinant RV mutants, we shed light on the molecular mechanism of NSP5 hyperphosphorylation during infection and its involvement in the assembly and maturation of replication-competent viroplasms.

Rotavirus (RV) replicates in round-shaped cytoplasmic viral factories, although how they assemble remains unknown. During RV infection, NSP5 undergoes hyperphosphorylation, which is primed by the phosphorylation of a single serine residue. The role of this posttranslational modification in the formation of viroplasms and its impact on virus replication remain obscure. Here, we investigated the role of NSP5 during RV infection by taking advantage of a modified fully tractable reverse-genetics system. A trans-complementing cell line stably producing NSP5 was used to generate and characterize several recombinant rotaviruses (rRVs) with mutations in NSP5. We demonstrate that an rRV lacking NSP5 was completely unable to assemble viroplasms and to replicate, confirming its pivotal role in rotavirus replication. A number of mutants with impaired NSP5 phosphorylation were generated to further interrogate the function of this posttranslational modification in the assembly of replication-competent viroplasms. We showed that the rRV mutant strains exhibited impaired viral replication and the ability to assemble round-shaped viroplasms in MA104 cells. Furthermore, we investigated the mechanism of NSP5 hyperphosphorylation during RV infection using NSP5 phosphorylation-negative rRV strains, as well as MA104-derived stable transfectant cell lines expressing either wild-type NSP5 or selected NSP5 deletion mutants. Our results indicate that NSP5 hyperphosphorylation is a crucial step for the assembly of round-shaped viroplasms, highlighting the key role of the C-terminal tail of NSP5 in the formation of replication-competent viral factories. Such a complex NSP5 phosphorylation cascade may serve as a paradigm for the assembly of functional viral factories in other RNA viruses.

IMPORTANCE The rotavirus (RV) double-stranded RNA genome is replicated and packaged into virus progeny in cytoplasmic structures termed viroplasms. The nonstructural protein NSP5, which undergoes a complex hyperphosphorylation process during RV infection, is required for the formation of these virus-induced organelles. However, its roles in viroplasm formation and RV replication have never been directly assessed due to the lack of a fully tractable reverse-genetics (RG) system for rotaviruses. Here, we show a novel application of a recently developed RG system by establishing a stable trans-complementing NSP5-producing cell line required to rescue rotaviruses with mutations in NSP5. This approach allowed us to provide the first direct evidence of the pivotal role of this protein during RV replication. Furthermore, using recombinant RV mutants, we shed light on the molecular mechanism of NSP5 hyperphosphorylation during infection and its involvement in the assembly and maturation of replication-competent viroplasms.

Re-evaluating the potential impact and cost-effectiveness of rotavirus vaccination in 73 Gavi countries: a modelling study

BACKGROUND

Previous studies have found rotavirus vaccination to be highly cost-effective in low-income countries. However, updated evidence is now available for several inputs (ie, rotavirus disease mortality rates, rotavirus age distributions, vaccine timeliness, and vaccine efficacy by duration of follow-up), new rotavirus vaccines have entered the market, vaccine prices have decreased, and cost-effectiveness thresholds have been re-examined. We aimed to provide updated cost-effectiveness estimates to inform national decisions about the new introduction and current use of rotavirus vaccines in Gavi countries.

METHODS

We calculated the potential costs and effects of rotavirus vaccination for ten successive birth cohorts in 73 countries previously and currently eligible for Gavi support, compared with no vaccination. We used a deterministic cohort model to calculate numbers of rotavirus gastroenteritis cases, outpatient visits, hospitalisations, and deaths between birth and 5 years, with and without rotavirus vaccination. We calculated treatment costs from the government and societal perspectives. The primary outcome measure was the incremental cost-effectiveness ratio (discounted US$ per disability-adjusted life-year averted). Country-specific model input parameters were based on the scientific literature, published meta-analyses, and international databases. We ran deterministic and probabilistic uncertainty analyses.

FINDINGS

Over the period 2018-27, rotavirus vaccination has the potential to prevent nearly 600 000 deaths in Gavi countries. Averted outpatient visits and hospitalisations could lead to treatment savings of approximately $484·1 million from the government perspective and $878·0 million from the societal perspective. The discounted dollars per disability-adjusted life-year averted has a very high probability (>90%) of being less than 0·5 times the gross domestic product per capita in 54 countries, and less than 1·0 times gross domestic product per capita in 63 countries.

INTERPRETATION

Rotavirus vaccination continues to represent good value for money across most Gavi countries despite lower rotavirus mortality estimates and more stringent willingness-to-pay thresholds.

FUNDING

Bill & Melinda Gates Foundation.

Related Enteric Viruses Have Different Requirements for Host Microbiota in Mice

Accumulating evidence suggests that intestinal bacteria promote enteric virus infection in mice. For example, previous work demonstrated that antibiotic treatment of mice prior to oral infection with poliovirus reduced viral replication and pathogenesis. Here, we examined the effect of antibiotic treatment on infection with coxsackievirus B3 (CVB3), a picornavirus closely related to poliovirus. We treated mice with a mixture of five antibiotics to deplete host microbiota and examined CVB3 replication and pathogenesis following oral inoculation. We found that, as seen with poliovirus, CVB3 shedding and pathogenesis were reduced in antibiotic-treated mice. While treatment with just two antibiotics, vancomycin and ampicillin, was sufficient to reduce CVB3 replication and pathogenesis, this treatment had no effect on poliovirus. The quantity and composition of bacterial communities were altered by treatment with the five-antibiotic cocktail and by treatment with vancomycin and ampicillin. To determine whether more-subtle changes in bacterial populations impact viral replication, we examined viral infection in mice treated with milder antibiotic regimens. Mice treated with one-tenth the standard concentration of the normal antibiotic cocktail supported replication of poliovirus but not CVB3. Importantly, a single dose of one antibiotic, streptomycin, was sufficient to reduce CVB3 shedding and pathogenesis while having no effect on poliovirus shedding and pathogenesis. Overall, replication and pathogenesis of CVB3 are more sensitive to antibiotic treatment than poliovirus, indicating that closely related viruses may differ with respect to their reliance on microbiota.IMPORTANCE Recent data indicate that intestinal bacteria promote intestinal infection of several enteric viruses. Here, we show that coxsackievirus, an enteric virus in the picornavirus family, also relies on microbiota for intestinal replication and pathogenesis. Relatively minor depletion of the microbiota was sufficient to decrease coxsackievirus infection, while poliovirus infection was unaffected. Surprisingly, a single dose of one antibiotic was sufficient to reduce coxsackievirus infection. Therefore, these data indicate that closely related viruses may differ with respect to their reliance on microbiota.

Rotavirus symptomatic infection among unvaccinated and vaccinated children in Valencia, Spain

BACKGROUND

Human group A rotavirus is the leading cause of severe acute gastroenteritis in young children worldwide. Immunization programs have reduced the disease burden in many countries. Vaccination coverage in the Autonomous Region of Valencia, Spain, is around 40%, as the rotavirus vaccine is not funded by the National Health System. Despite this low-medium vaccine coverage, rotavirus vaccination has substantially reduced hospitalizations due to rotavirus infection and hospital-related costs. However, there are very few studies evaluating symptomatic rotavirus infections not requiring hospitalization in vaccinated children. The objective of this study was to investigate symptomatic rotavirus infections among vaccinated children in the health area served by the Hospital Clínico Universitario of Valencia, Spain, from 2013 to 2015.

METHODS

A total of 133 children younger than 5 years of age with rotavirus infection were studied. Demographic and epidemiological data were collected and informed consent from their caretakers obtained. Rotavirus infection was detected by immunological methods and G/P rotavirus genotypes were determined by RT-PCR, following standard procedures from the EuroRotaNet network.

RESULTS

Forty infants (30.1%; 95% CI: 22.3-37.9) out of 133 were diagnosed with symptomatic rotavirus infection despite having been previously vaccinated, either with RotaTeq (85%) or with Rotarix (15%). Children fully vaccinated against rotavirus (24.8%), partially vaccinated (5.3%) and unvaccinated (69.9%) were found. The infecting genotypes showed high G-type diversity, although no significant differences were found between the G/P genotypes infecting vaccinated and unvaccinated children during the same time period. G9P[8], G12P[8] and G1P[8] were the most prevalent genotypes. Severity of gastroenteritis symptoms required 28 (66.6%) vaccinated and 67 (73.6%) unvaccinated children to be attended at the Emergency Room.

CONCLUSION

Rotavirus vaccine efficacy in reducing the incidence of severe rotavirus infection has been well documented, but symptomatic rotavirus infection can sometimes occur in vaccinees.

Rotavirus C: prevalence in suckling piglets and development of virus-like particles to assess the influence of maternal immunity on the disease development

Rotavirus C (RVC) has been detected increasingly in humans and swine in different countries, including the US. It is associated with significant economic losses due to diarrheal disease in nursing piglets. In this study we aimed: (1) to determine the prevalence of RVC in healthy and diarrheic suckling piglets on US farms; and (2) to evaluate if maternal antibody (Ab) levels were associated with protection of newborn suckling piglets against RVC. There was a significantly higher prevalence (p = 0.0002) of litters with diarrhea born to gilts compared with those born to multiparous sows. Of 113 nursing piglet fecal samples tested, 76.1% were RVC RNA positive. Fecal RVC RNA was detected in significantly (p = 0.0419) higher quantities and more frequently in piglets with diarrhea compared with healthy ones (82.5 vs. 69.9%). With the exception of the historic strain Cowden (G1 genotype), field RVC strains do not replicate in cell culture, which is a major impediment for studying RVC pathogenesis and immunity. To circumvent this, we generated RVC virus-like particles (VLPs) for Cowden (G1), RV0104 (G3) and RV0143 (G6) and used them as antigens in ELISA to detect swine RVC Abs in serum and milk from the sows. Using RVC-VLP Ab ELISA we demonstrated that sows with diarrheic litters had significantly lower RVC IgA and IgG Ab titers in milk compared to those with healthy litters. Thus, our data suggest that insufficient lactogenic protection provided by gilts plays a key role in the development of and the increased prevalence of clinical RVC disease.

Heterogeneity in potential impact and cost-effectiveness of ETEC and Shigella vaccination in four sub-Saharan African countries

Diarrheal disease burden has become more heterogenous in low- and lower middle-income countries as access to clean water, sanitation and health care has increased in wealthier urban populations. Enterotoxigenic Escherichia coli (ETEC) and Shigella are among the top five causes of diarrheal mortality in children living in sub-Saharan Africa. Here, we explored how accounting for subnational and economic heterogeneity in ETEC and Shigella disease burden affects projected vaccine impact and cost-effectiveness of standalone ETEC and Shigella vaccines during the first decade after introduction in four sub-Saharan African countries. We developed dynamic models for provincial areas and socioeconomic subpopulations of children in the Democratic Republic of Congo (DRC), Kenya, Zambia, and Zimbabwe. We estimated deaths and morbidity due to ETEC and Shigella diarrhea plus additional deaths from other infectious diseases attributable to ETEC- and Shigella-induced stunting. We analyzed cost-effectiveness using Incremental Cost-Effectiveness Ratios (ICERs) with Disability-Adjusted Life Years (DALYs) and Moderate-and-Severe Diarrheal episodes (MSD) averted as denominators. Other infectious disease deaths due to induced stunting accounted for 9-28% and 9-32% of the total provincial level ETEC and Shigella disease burden, respectively, across these four countries from years 2025 to 2034. Our results indicated that the lowest and most cost-effective provincial DALYs averted ICERs were below $600 and $500/DALY averted for ETEC and Shigella vaccination, respectively in Zimbabwe. ICERs were the highest in Zambia and Kenya, where all provincial ICERs where above $2000/DALY. The highest national and provincial MSD averted ICERs were in DRC, while the lowest were in Kenya and Zimbabwe. Vaccinations were most cost-effective in averting DALYs in lower wealth subpopulations living in the highest burden provincial areas. Our approach focused on subnational heterogeneity in ETEC and Shigella burden and vaccination access found that impact and cost-effectiveness were more favorable if vaccinations reach the most vulnerable children in underserved provinces.

Bayesian Random Effect Modeling for analyzing spatial clustering of differential time trends of diarrhea incidences

In 2012, nearly 644,000 people died from diarrhea in sub-Saharan Africa. This is a significant obstacle towards the achievement of the Sustainable Development Goal 3 of ensuring a healthy life and promoting the wellbeing at all ages. To enhance evidence-based site-specific intervention and mitigation strategies, especially in resource-poor countries, we focused on developing differential time trend models for diarrhea. We modeled the logarithm of the unknown risk for each district as a linear function of time with spatially varying effects. We induced correlation between the random intercepts and slopes either by linear functions or bivariate conditional autoregressive (BiCAR) priors. In comparison, models which included correlation between the varying intercepts and slopes outperformed those without. The convolution model with the BiCAR correlation prior was more competitive than the others. The inclusion of correlation between the intercepts and slopes provided an epidemiological value regarding the response of diarrhea infection dynamics to environmental factors in the past and present. We found diarrhea risk to increase by 23% yearly, a rate far exceeding Ghana’s population growth rate of 2.3%. The varying time trends widely varied and clustered, with the majority of districts with at least 80% chance of their rates exceeding the previous years. These findings can be useful for active site-specific evidence-based planning and interventions for diarrhea.

Introducing rotavirus vaccine in the Universal Immunization Programme in India: From evidence to policy to implementation

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India became one of the first countries in Asia to introduce rotavirus vaccine.

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Rotavirus vaccine is being expanded to the entire country in a phase wised manner.

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The new vaccine introduction strengthened the programme rather than burdening it.

Background

In 2016, India became one of the first countries in Asia to introduce an indigenously manufactured rotavirus vaccine. However, any new vaccine introduction needs to be meticulously planned to allow for strengthening of the existing immunization systems instead of burdening them.

Methods

The process of rotavirus vaccine introduction in India started with the establishment of National Rotavirus Surveillance Network in 2005 which generated relevant evidence to inform policy level decisions to introduce the vaccine. The preparatory activities started with assessment of health systems and closing any gaps. This was followed by development of vaccine specific training packages and cascade training for programme managers and health workers. The introduction was complemented with strong communications systems and media involvement to allow for good acceptability of the vaccine on the ground. Each step of introduction was led by the government and technically supported by development partners.

Results

India introduced rotavirus vaccine in a phased wise manner. In the first two phases the vaccine has been introduced in nine states of the country accounting for nearly 35% of the annual birth cohort of the country. From March 2016 to November 2017, approximately 13,260,000 rotavirus vaccine doses were administered in the country. The vaccine was well accepted by both the health workers and parents/caregivers.

Conclusion

Rotavirus vaccine introduction in India is an excellent example of how government stewardship with well-defined roles for development partners can allow a new vaccine introduction to be used as a system strengthening activity.

Effectiveness of rotavirus vaccines in an Australian population: A case-control study

OBJECTIVE

Two rotavirus vaccines (RV1 and RV5) were included in the publicly funded National Immunisation Program in Australia from July 2007. The programme in Western Australia initially provided RV1 (at ages 2 and 4 months) and then switched to RV5 (at ages 2, 4 and 6 months) from July 2009. This retrospective case-control study was conducted to assess the effectiveness of rotavirus vaccine against laboratory confirmed and notified cases of rotavirus infection among children aged <5 years.

METHODS

Case-subjects were identified as vaccine-eligible children (born from 1 May 2007) who were notified as having rotavirus infection during the period 2009-2011. The control group was vaccine-eligible children notified as having Campylobacter or Salmonella infection during the same period. Individual rotavirus immunisation status was ascertained from a population-based immunisation register. Full-dose and partial-dose vaccine effectiveness (VE) were calculated for both vaccines using the adjusted odds ratio (OR) of vaccination for cases versus controls (VE = (1 - OR)*100%).

RESULTS

Overall, 282 cases and 883 controls were included. The adjusted VE for a full course of either rotavirus vaccine was 72% (95% CI: 56-82) and 71% (95% CI: 50-84) for partial vaccination (one dose of RV1 or one/two doses of RV5). The VE for a complete 3-dose course of RV5 was 82% (95% CI: 59-92) and for a full 2-dose course of RV1 was 73% (95% CI: 55-83).

CONCLUSIONS

RV1 and RV5 were both effective in preventing laboratory confirmed and notified rotavirus infections among children aged <5 years. Even incomplete courses of vaccination conferred good protection.

Diverse Mechanisms Underlie Enhancement of Enteric Viruses by the Mammalian Intestinal Microbiota

Over the past two decades, there has been tremendous progress in understanding the impact of the intestinal microbiota on mammalian metabolism, physiology, and immune development and function. There has also been substantial advancement in elucidating the interplay between commensal and pathogenic bacteria. Relatively more recently, researchers have begun to investigate the effect of the intestinal microbiota on viral pathogenesis. Indeed, a growing body of literature has reported that commensal bacteria within the mammalian intestinal tract enhance enteric virus infections through a variety of mechanisms. Commensal bacteria or bacterial glycans can increase the stability of enteric viruses, enhance virus binding to host receptors, modulate host immune responses in a proviral manner, expand the numbers of host cell targets, and facilitate viral recombination. In this review, we will summarize the current literature exploring these effects of the intestinal microbiota on enteric virus infections.

Potential impact and cost-effectiveness of future ETEC and Shigella vaccines in 79 low- and lower middle-income countries

While diarrhea mortality in children has declined over the last two decades, there has been a slower decline in diarrheal episodes. Repeated diarrheal episodes are associated with childhood stunting, which leads to increased mortality risk from infectious diseases. Vaccine candidates are under development for enterotoxigenic Escherichia coli [ETEC] and Shigella, important enteric pathogens in children in low income countries. These future vaccines could significantly reduce diarrheal burden, prevent ETEC- and Shigella-induced stunting, and stunting-associated mortality. We developed a cost-effectiveness model for two putative standalone ETEC and Shigella vaccine candidates to evaluate vaccine impact on mortality, morbidity, stunting, and stunting-associated deaths from other infectious diseases. We modeled impact over the first ten years after vaccine introduction in children under five years old living in 79 low and low-middle income countries. ETEC and Shigella diarrhea would cause an estimated 239,300 [95% UL: 179,700-309,800] and 340,300 [256,500-440,800] child deaths, respectively, from years 2025 to 2034. Most of these deaths would occur in AFRO countries. ETEC and Shigella moderate-to-severe diarrheal episodes would result in over 13.7 [8.4-19.0] and 21.4 [13.1-29.8] million stunted children, respectively. Introducing ETEC or Shigella vaccine each with 60% efficacy could prevent 92,000 [61,000-129,000] ETEC and 126,600 [84,000-179,000] Shigella direct deaths and 21,400 [11,300-34,800] ETEC- and 34,200 [18,000-56,000] Shigella-induced stunting deaths. ETEC ICERs ranged from $2172/DALY [1457-4369] in AFRO to $19,172/DALY [12,665-39,503] in EURO. Shigella ICERs ranged from $952/DALY [632-2001] in EMRO to $640,316/DALY [434,311-1,297,192] in EURO. Limitations of this analysis include uncertainty of vaccine efficacy, duration of protection, and vaccine price. Inclusion of other infectious disease mortality due to stunting provides a more accurate assessment of total ETEC and Shigella disease burden and increased the projected impact and cost-effectiveness of vaccination. Introducing vaccines only in high burden countries and regions could substantially reduce cost without substantially reducing impact.

Recombinant Subunit Rotavirus Trivalent Vaccine Candidate: Physicochemical Comparisons and Stability Evaluations of Three Protein Antigens

Although live attenuated Rotavirus (RV) vaccines are available globally to provide protection against enteric RV disease, efficacy is substantially lower in low- to middle-income settings leading to interest in alternative vaccines. One promising candidate is a trivalent nonreplicating RV vaccine, comprising 3 truncated RV VP8 subunit proteins fused to the P2 CD4⁺ epitope from tetanus toxin (P2-VP8-P[4/6/8]). A wide variety of analytical techniques were used to compare the physicochemical properties of these 3 recombinant fusion proteins. Various environmental stresses were used to evaluate antigen stability and elucidate degradation pathways. P2-VP8-P[4] and P2-VP8-P[6] displayed similar physical stability profiles as function of pH and temperature while P2-VP8-P[8] was relatively more stable. Forced degradation studies revealed similar chemical stability profiles with Met¹ most susceptible to oxidation, the single Cys residue (at position 173/172) forming intermolecular disulfide bonds (P2-VP8-P[6] was most susceptible), and Asn⁷ undergoing the highest levels of deamidation. These results are visualized in a structural model of the nonreplicating RV antigens. The establishment of key structural attributes of each antigen, along with corresponding stability-indicating methods, have been applied to vaccine formulation development efforts (see companion paper), and will be utilized in future analytical comparability assessments.

Molecular characterization of human group A rotavirus genotypes circulating in Rawalpindi, Islamabad, Pakistan during 2015-2016

Group A rotaviruses (RVA) are one of the major causes of acute gastroenteritis (AGE) in young children worldwide. Owing to lack of proper surveillance programs and health facilities, developing countries of Asia and Africa carry a disproportionately heavy share of the RVA disease burden. The aim of this hospital-based study was to investigate the circulation of RVA genotypes in Rawalpindi and Islamabad, Pakistan in 2015 and 2016, prior to the implementation of RVA vaccine. 639 faecal samples collected from children under 10 years of age hospitalized with AGE were tested for RVA antigen by ELISA. Among 171 ELISA positive samples, 143 were successfully screened for RT-PCR and sequencing. The prevalence of RVA was found to be 26.8% with the highest frequency (34.9%) found among children of age group 6-11 months. The most predominant circulating genotypes were G3P[8] (22.4%) followed by G12P[6] (20.3%), G2P[4] (12.6%), G1P[8] (11.9%), G9P[6] (11.9%), G3P[4] (9.1%), G1P[6] (4.2%), G9P[8] (4.2%), and G3P[6] (0.7%). A single mixed genotype G1G3P[8] was also detected. The findings of this study provide baseline data, that will help to assess if future vaccination campaigns using currently available RVA vaccine will reduce RVA disease burden and instigate evolutionary changes in the overall RVA biology. The high prevalence of RVA infections in Pakistan require to improve and strengthen the surveillance and monitoring system for RVA. This will provide useful information for health authorities in planning public health care strategies to mitigate the disease burden caused by RVA.

Vitamin D Alleviates Rotavirus Infection through a Microrna-155-5p Mediated Regulation of the TBK1/IRF3 Signaling Pathway In Vivo and In Vitro

(1) Background: Vitamin D (VD) plays a vital role in anti-viral innate immunity. However, the role of VD in anti-rotavirus and its mechanism is still unclear. The present study was performed to investigate whether VD alleviates rotavirus (RV) infection through a microRNA-155-5p (miR-155-5p)-mediated regulation of TANK-binding kinase 1 (TBK1)/interferon regulatory factors 3 (IRF3) signaling pathway in vivo and in vitro. (2) Methods: The efficacy of VD treatment was evaluated in DLY pig and IPEC-J2. Dual-luciferase reporter activity assay was performed to verify the role of miR-155-5p in 1α,25-dihydroxy-VD₃ (1,25D3) mediating the regulation of the TBK1/IRF3 signaling pathway. (3) Results: A 5000 IU·kg^–1 dietary VD₃ supplementation attenuated RV-induced the decrease of the villus height and crypt depth (p < 0.05), and up-regulated TBK1, IRF3, and IFN-β mRNA expressions in the jejunum (p < 0.05). Incubation with 1,25D3 significantly decreased the RV mRNA expression and the RV antigen concentration, and increased the TBK1 mRNA and protein levels, and the phosphoprotein IRF3 (p-IRF3) level (p < 0.05). The expression of miR-155-5p was up-regulated in response to an RV infection in vivo and in vitro (p < 0.05). 1,25D3 significantly repressed the up-regulation of miR-155-5p in vivo and in vitro (p < 0.05). Overexpression of miR-155-5p remarkably suppressed the mRNA and protein levels of TBK1 and p-IRF3 (p < 0.01), while the inhibition of miR-155-5p had an opposite effect. Luciferase activity assays confirmed that miR-155-5p regulated RV replication by directly targeting TBK1, and miR-155-5p suppressed the TBK1 protein level (p < 0.01). (4) Conclusions: These results indicate that miR-155-5p is involved in 1,25D3 mediating the regulation of the TBK1/IRF3 signaling pathway by directly targeting TBK1.

Evaluation of the performance of a multiplex reverse transcription polymerase chain reaction kit as a potential diagnostic and surveillance kit for rotavirus in Kenya

Background

Diarrhea is a serious concern worldwide, especially in developing countries. Rotavirus is implicated in approximately 400,000 infant deaths annually. It is highly contagious elevating the risk of outbreaks especially in enclosed settings such as daycare centers, hospitals, and boarding schools. Reliable testing methods are critical for early detection of infections, better clinical management, pathogen surveillance and evaluation of interventions such as vaccines. Enzyme immunoassays have proved to be reliable and practical in most settings; however, newer multiplex reverse transcription polymerase assays have been introduced in the Kenya market but have not been evaluated locally.

Methods

Stool samples collected from an ongoing Surveillance of Enteric Pathogens Causing diarrheal illness in Kenya (EPS) study were used to compare an established enzyme immunoassay, Premier™ Rotaclone® (Meridian Bioscience, Cincinnati, Ohio, U.S.A.), that can only detect group A rotavirus against a novel multiplex reverse transcription polymerase chain reaction kit, Seeplex® Diarrhea-V ACE Detection (Seegene, Seoul, Republic of Korea), that can detect rotavirus, astrovirus, adenovirus, and norovirus genogroups I and II. Detection frequency, sensitivity, specificity, turnaround time, and cost were compared to determine the suitability of each assay for clinical work in austere settings versus public health work in well-funded institutes in Kenya.

Results

The Premier™ Rotaclone® kit had a detection frequency of 11.2%, sensitivity of 77.8%, specificity of 100%, turnaround time of 93 min and an average cost per sample of 13.33 United States dollars (USD). The Seeplex® Diarrhea-V ACE Detection kit had a detection frequency of 16.0%, sensitivity of 100%, specificity of 98.1%, turnaround time of 359 min and an average cost per samples 32.74 United States dollars respectively. The detection frequency sensitivity and specificity of the Seeplex® Diarrhea-V ACE Detection kit mentioned above are for rotavirus only.

Conclusions

The higher sensitivity and multiplex nature of the Seeplex® Diarrhea-V ACE Detection kit make it suitable for surveillance of enteric viruses circulating in Kenya. However, its higher cost, longer turnaround time and complexity favor well-resourced clinical labs and research applications. The Premier™ Rotaclone®, on the other hand, had a higher specificity, shorter turnaround time, and lower cost making it more attractive for clinical work in low complexity labs in austere regions of the country. It is important to continuously evaluate assay platforms' performance, operational cost, turnaround time, and usability in different settings so as to ensure quality results that are useful to the patients and public health practitioners.

Sustained reduction in rotavirus-coded hospitalizations in children aged <5 years after introduction of self-financed rotavirus vaccines in Japan

This is an extension of our previous study, which evaluated the incidence of seasonal rotavirus gastroenteritis (RVGE) hospitalizations in children aged <5 years from 2009 to 2015 in Japan. Here, we evaluated the incidence of RVGE hospitalizations in children aged <10 years during the rotavirus season (January‒June) from 2009 to 2017 in Japan, before and after the monovalent and pentavalent rotavirus vaccines were introduced in November 2011 and July 2012, using the same health insurance claims database and study methods. In children aged <5 years, the incidence of RVGE hospitalizations greatly declined in 2014 after vaccine introduction, consistent with our previous findings, and the decline was sustained until 2017. However, in children aged ≥5‒<10 years, no apparent trend for a continuous decline in RVGE hospitalizations was observed during the study period. Improved RV vaccination coverage may lead to a further reduction in severe RVGE in Japan.

Clinical efficacy of oral immunoglobulin Y in infant rotavirus enteritis: Systematic review and meta-analysis

BACKGROUND

Rotavirus (RV) can cause vomiting and diarrhea in infants and children, and could be treated clinically with immunoglobulin Y (IgY), which is an immunoglobulin extracted from chicken yolk. There is no systematic evaluation of immunoglobulin in the treatment of rotavirus enteritis. Therefore, we systematically evaluated rotavirus enteritis with oral immunoglobulin Y therapy using meta-analysis.

METHODS

We conducted a systematic search in CNKI, WANFANG DATA, VIP, PubMed, and the Cochrane Library databases (up to April 30, 2018). Using Revman 5.3 software for meta-analysis.

RESULTS

A total of 2626 subjects with rotavirus diarrhea from 17 randomized clinical trials were included in the meta-analysis. Of these, 1347 subjects received oral immunoglobulin Y and 1279 subjects received conventional treatment. The results of the meta-analysis indicated that the total number of effective cases and effective rates of immunoglobulin Y in treatment of rotavirus enteritis in infants and children was statistically different from that in the control group (odds ratio [OR] = 3.87, 95% confidence interval [CI] (3.17, 4.74), P < .00001) and (OR = 3.63, 95% CI [2.75, 4.80], P < .00001).

CONCLUSIONS

Immunoglobulin Y is effective in the treatment of infantile rotavirus enteritis. Oral immunoglobulin Y can be widely used in the treatment of rotavirus enteritis in clinic.

Global impact of rotavirus vaccine introduction on rotavirus hospitalisations among children under 5 years of age, 2008-16: findings from the Global Rotavirus Surveillance Network

BACKGROUND

Rotavirus vaccine use in national immunisation programmes has led to declines in hospital admissions for rotavirus gastroenteritis among children; however, the global impact of rotavirus vaccine introduction has not been described using primary data. We describe the impact of rotavirus vaccine introduction on admissions for acute rotavirus gastroenteritis in primarily low-income and middle-income countries, using 9 years of data from the WHO-coordinated Global Rotavirus Surveillance Network (GRSN).

METHODS

Between Jan 1, 2008, and Dec 31, 2016, children younger than 5 years of age who were admitted to hospital with acute gastroenteritis were prospectively enrolled in GRSN sites. We included sites that enrolled children and collected stool specimens monthly and tested at least 100 specimens annually in the impact analysis, with a separate analysis taking into account site continuity. We compared proportions of acute gastroenteritis cases positive for rotavirus in the pre-vaccine and post-vaccine periods and calculated mean proportion changes for WHO regions, with 95% CIs; these findings were then compared with interrupted time series analyses. We did further sensitivity analyses to account for rotavirus vaccination coverage levels and sites that collected specimens for at least 11 months per year and tested at least 80 specimens per year. We also analysed the age distribution of rotavirus-positive cases before and after vaccine introduction.

FINDINGS

403 140 children younger than 5 years of age admitted to hospital with acute gastroenteritis from 349 sites in 82 countries were enrolled over the study period, of whom 132 736 (32·9%) were positive for rotavirus. We included 305 789 children from 198 sites in 69 countries in the impact analysis. In countries that had not introduced rotavirus vaccine in their national immunisation programmes, rotavirus was detected in 38·0% (95% CI 4·8-73·4) of admissions for acute gastroenteritis annually whereas in those that have introduced the vaccine, rotavirus was detected in 23·0% (0·7-57·7) of admissions for acute gastroenteritis, showing a 39·6% (35·4-43·8) relative decline following introduction. Interrupted time series analyses confirmed these findings. Reductions by WHO regions ranged from 26·4% (15·0-37·8) in the Eastern Mediterranean Region to 55·2% (43·0-67·4) in the European Region and were sustained in nine countries (contributing up to 31 sites) for 6-10 years. The age distribution of children with rotavirus gastroenteritis shifted towards older children after rotavirus vaccine introduction.

INTERPRETATION

A significant and sustained reduction in the proportion of hospital admissions for acute gastroenteritis due to rotavirus was seen among children younger than 5 years in GRSN sites following rotavirus vaccine introduction. These findings highlight the need to incorporate rotavirus vaccines into immunisation programmes in countries that have not yet introduced them and underline the importance of high-quality surveillance.

FUNDING

The GRSN receives funding from Gavi, the Vaccine Alliance and the US Centers for Disease Control and Prevention. No specific funding was provided for this Article.

Molecular and serologic characterization of rotavirus from children with acute gastroenteritis in northern Iran, Gorgan

BACKGROUND

The pattern and distribution of human rotavirus genotypes in young children in developing countries play an important role in epidemiological studies, as well as providing a strategy for the development of future rotavirus vaccine.

METHODS

We evaluated stool samples from 349 children with acute gastroenteritis from Northern Iran (Gorgan city, Golestan province). Polyacrylamide Gel Electrophoresis (PAGE) and Latex Agglutination Test (LAT) were utilized to determine the prevalence of human rotavirus in fecal samples. Moreover semi-multiplex RT-PCR technique was carried out in order to determine the P and G genotypes of human rotavirus in rotavirus-positive samples.

RESULTS

A total of 46 rotavirus-positive samples were G and P genotyped. Whereas 28 (60.8%) fecal specimens contained only one rotavirus strain, 14 (30.4%) were mixed rotavirus infections and 4 (8.8%) was non-typeable. Overall, during the study, 57.82% of strains identified as genotype G1, G2 (18.70%), G3 (4.69%), G4 (3.13%), G8 (3.13%), G9 (6.26%) and non-typeable G (6.26%). From all these mentioned rotavirus strains, 46 were characterized as P [8] (97.80%) and P [4] (2.20%).Our analysis of the G and P genotyping of strains from all 46 rotavirus-infected children has revealed that 4/46(6.26%) of G type strains were non-typeable. The predominant single G/P combination was G1P [8] (57.82%), followed by, G2P [8] (16.98%), G2P [4] (1.72%), G3P [8] (4.69%), G4P [8] (3.13%) G8P [8] (3.13%), G9P [8] (6.26%) and four cases of non-typeable G (6.26%). Rotavirus was detected in 39 specimens (11.17%) by PAGE and in 38 specimens (10.88%) by LAT. Both tests were 100% specific; however, the LAT was 82.61% sensitive compared to the PAGE, which was 84.78% sensitive.

CONCLUSIONS

The results suggest that to characterize rotavirus strains as well as design new effective vaccines for children with acute gastroenteritis, a large-scale study is needed in future.

Systematic review of the rotavirus infection burden in the WHO-EMRO region

Rotavirus gastroenteritis imposes a heavy burden on low- and middle-income countries. The World Health Organization defines the Eastern Mediterranean region (WHO-EMRO) as a diverse area in terms of socioeconomic status and health indicators. Rotavirus vaccination has been introduced, at least partially, in 19 out of the 22 EM countries; however, vaccine coverage remains low, and data on rotavirus disease burden is scarce.Available data on rotavirus prevalence, seasonality, vaccination status, and genotype evolution was systematically compiled following a literature review that identified 165 relevant WHO-EMRO epidemiology studies published between 1990 and 2017.Although the infectious agents responsible for acute gastroenteritis vary over time, rotavirus remained the leading cause of acute gastroenteritis in children, as seen in 76.3% of reviewed publications. Younger children (<2 years old) were at higher risk and thus increased vaccination coverage and surveillance systems are required to reduce the rotavirus gastroenteritis burden in WHO-EMRO countries.

Budget Impact Analysis of Rotavirus Vaccine Adoption in the Childhood Immunization Schedule of Iran

OBJECTIVES

To examine the budget impact of introducing the RotaTeq® vaccine (Merck and Co Inc, West Point, PA) to the national immunization program in Iran.

METHODS

The pre- and postvaccine introduction costs were compared. The total annual costs included the vaccination and diarrhea treatment costs. The health outcome was the estimated annual cases of the disease. To evaluate the net budget impact, the annual prevaccine introduction cost was reduced from the postvaccine introduction cost. The sensitivity analysis was done to reduce the uncertainties.

RESULTS

The total cost of vaccination for 5 years would be more than $184 million. Nevertheless, the financial savings would be about $45 million and $7.5 million because of the reduction in the number of patients after vaccination in inpatient and outpatient sectors, respectively. So the incremental cost would be $131 450 210 during 5 years of immunization.

CONCLUSIONS

The results show that the inclusion of rotavirus vaccine in the national vaccination program would have a significant effect on health budgets and would raise government expenditure.