Genotypes of rotavirus strains circulating in Amman, Jordan, in 2006/07 and their significance for the potential effectiveness of future rotavirus vaccination

Systematic literature review and meta-analysis on the prevalence of rotavirus genotypes in Europe and the Middle East in the post-licensure period

Previous systematic literature reviews of rotavirus genotype circulation in Europe and the Middle East are limited because they do not include country-specific prevalence data. This study documents country-specific evidence on the prevalence of rotavirus genotypes in Europe and the Middle East to enable more precise epidemiological modeling and contribute to the evidence-base about circulating rotavirus genotypes in the post-vaccination era. This study systematically searched PubMed, Embase and Scopus for all empirical epidemiological studies that presented genotype-specific surveillance data for countries in Europe and the Middle East published between 2006 and 2021. The STROBE checklist was used to assess the quality of included studies. Proportional meta-analysis was conducted using the generic inverse variance method with arcsine transformation and generalized linear-mixed models to summarize genotype prevalence. Our analysis estimated the genotype prevalence by country across three date categories corresponding with rotavirus seasons: 2006-2010, 2011-2015, 2016-2021. A total of 7601 deduplicated papers were identified of which 88 studies were included in the final review. Rotavirus genotypes exhibited significant variability across regions and time periods, with G1P[8], G2P[4], G3P[8], G4P[8], G9P[8], and, to a lesser extent G12P[8], being the most prevalent genotypes through different regions and time-periods. Uncommon genotypes included G3P[9] in Poland, G2P[6] in Iraq, G4P[4] in Qatar, and G9P[4] as reported by the European Rotavirus Network. There was high genotype diversity with routinely identified genotypes being G1P[8], G2P[4], G3P[8], G4P[8], and G9P[8]; there was high variability across time periods and regions. Continued surveillance at the national and regional levels is relevant to support further research and inform public health decision-making.

Molecular epidemiology, genetic diversity, and vaccine availability of viral acute gastroenteritis in the middle East and North Africa (MENA) region

Acute gastroenteritis is the cause of considerable mortality and morbidity worldwide, particularly among children under five years in underdeveloped countries. Most acute gastroenteritis (AGE) cases are attributed to viral etiologies, including rotavirus, norovirus, adenovirus, astrovirus, and sapovirus. This paper aimed to determine the prevalence rate of different viral etiologies of AGE in the Middle East and North Africa (MENA) region. Moreover, this paper explored rotavirus phylogenetic relatedness, compared VP7 and VP4 antigenic regions of rotavirus with vaccine strains, and explored the availability of vaccines in the MENA region. The literature search identified 160 studies from 18 countries from 1980 to 2019. The overall prevalence of rotavirus, norovirus, adenovirus, astrovirus, and sapovirus were 29.8 %, 13.9 %, 6.3 %, 3.5 %, and 3.2 % of tested samples, respectively. The most common rotavirus genotype combinations in the MENA region were G1P[8], G9P[9], and G2P[4], whereas GII.4 was the predominant norovirus genotype all of which were reported in almost all the studies with genotyping data. The comparison of VP7 and VP4 between circulating rotavirus in the MENA region and vaccine strains has revealed discrete divergent regions, including the neutralizing epitopes. Rotavirus vaccine was introduced to most of the countries of the MENA region; however, only a few studies have assessed the effectiveness of vaccine introduction. This paper provides a comprehensive update on the prevalence of the different viral agents of AGE in the MENA region.

Epidemiological, molecular, and clinical features of rotavirus infections among pediatrics in Qatar

Acute gastroenteritis (AGE) remains a major cause of diarrhea in developing and developed countries. Rotavirus (RV) is a leading cause of severe pediatric diarrhea worldwide. Here we report on the prevalence of circulating genotypes in association with demographics and clinical manifestations outcomes in Qatar. A total of 231 RV-positive fecal samples were collected from children suffering from AGE during 3 years study period between June 2016 and June 2019. The age of the subjects ranged between 2 months and 14 years (median of 16 months). The VP4 and VP7 were amplified and sequenced. Phylogenetic analyses were performed using MEGA7.0. Pearson's chi-squared test was used to determine significant differences for comparisons of general categorical variables. RV infections were most common in children between 1 and 3 years of age (49%), followed by those < 1 year and > 3 years of age (33% and 28%, respectively). RV infections were more frequent in males than females, with a ratio of 1.4:1. RV infections occurred throughout the year, with a noticeable increase in summer (42.8%) and a drop in winter (20.1%). RV genotypes G3P[8] (30.8%), G2P[8] (12.3%), G4P[8] (11.7%), and G1P[8] (10.4%) were the common genotypes during the study period. The G3P[8] strain detected in our study revealed similarities to the equine-like G3P[8] (10.3%; 24/231) (KT988229.1), Wa-like genomic constellation (9%; 21/231) (MF563894.1), and DS-1-like strains (6.4%; 15/231) (LC386081.1). Based on the Vesikari score system, severe clinical illness including diarrhea and vomiting (average frequency: 4 to 5 times/day) was recorded for G3P[8] group, followed by G9P[8], G4P[8], and G1P[8]. Higher incidence for G3P[8], G2P[8], G4P[8], and G1P[8] were reported in Qatari subjects compared to other nationalities. The multinational status of a small country explains the wide diversity of circulating RV genotypes in Qatar. The highest prevalence and severe illnesses were recorded to G3P[8], which is different from other surrounding countries/global levels.

The Molecular Epidemiology and Phylogeny of Torque Teno Virus (TTV) in Jordan

Torque teno virus (TTV) is the most common component of the human blood virobiota. Little is known, however, about the prevalence of TTV in humans and the most common farm domesticates in Jordan, or the history and modality of TTV transmission across species lines. We therefore tested sera from 396 Jordanians and 171 farm animals for the presence of TTV DNA using nested 5'-UTR-PCR. We then performed phylogenetic, ordination and evolutionary diversity analyses on detected DNA sequences. We detected a very high prevalence of TTV in Jordanians (~96%); much higher than in farm animal domesticates (~29% pooled over species). TTV prevalence in the human participants is not associated with geography, demography or physical attributes. Phylogenetic, ordination and evolutionary diversity analyses indicated that TTV is transmitted readily between humans across the geography of the country and between various species of animal domesticates. However, the majority of animal TTV isolates seem to derive from a single human-to-animal transmission event in the past, and current human-animal transmission in either direction is relatively rare. In conclusion, animal TTV in Jordan is historically derived from human variants; however, ongoing human-animal TTV exchange is minimal and zoonotic infection seems to be of limited importance.

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.

Review of global rotavirus strain prevalence data from six years post vaccine licensure surveillance: is there evidence of strain selection from vaccine pressure?

Comprehensive reviews of pre licensure rotavirus strain prevalence data indicated the global importance of six rotavirus genotypes, G1P[8], G2P[4], G3P[8], G4P[8], G9P[8] and G12P[8]. Since 2006, two vaccines, the monovalent Rotarix (RV1) and the pentavalent RotaTeq (RV5) have been available in over 100 countries worldwide. Of these, 60 countries have already introduced either RV1 or RV5 in their national immunization programs. Post licensure vaccine effectiveness is closely monitored worldwide. This review aimed at describing the global changes in rotavirus strain prevalence over time. The genotype distribution of the nearly 47,000 strains that were characterized during 2007-2012 showed similar picture to that seen in the preceding period. An intriguing finding was the transient predominance of heterotypic strains, mainly in countries using RV1. Unusual and novel antigen combinations continue to emerge, including some causing local outbreaks, even in vaccinated populations. In addition, vaccine strains have been found in both vaccinated infants and their contacts and there is evidence for genetic interaction between vaccine and wild-type strains. In conclusion, the post-vaccine introduction strain prevalence data do not show any consistent pattern indicative of selection pressure resulting from vaccine use, although the increased detection rate of heterotypic G2P[4] strains in some countries following RV1 vaccination is unusual and this issue requires further monitoring.

Prevalence of rotavirus genotypes in South Korea in 1989-2009: implications for a nationwide rotavirus vaccine program

The epidemiology of human group A rotavirus was analyzed by examining genotypic data acquired from 1989 to 2009 in South Korea. This information was derived from all the available published articles on rotavirus studies in South Korea, retrieved from both the PubMed and KoreaMed databases. Four common G types (G1, G2, G3, and G4) and three common P types (P[8], P[4], and P[6]) accounted for approximately 93% and 99% of the rotavirus reports, respectively. The G9 type was frequently detected after 2000, and because of this prevalence, it is considered to be the fifth most important G type rotavirus after the G1.G4 genotypes. Less common G types of the virus such as G12, G11, and G10 were detected in some geographic settings, and it is important to consider the context of these subtypes and their epidemiological significance. The P[9] virus genotype was observed in the study and has been discussed in many other studies; however, the P[3], P[10] and P[25] genotypes were rarely detected in the epidemiological research. In general, the distributions of the G and P genotypes showed temporal and geographical fluctuations, and a nationwide rotavirus vaccine program that targeted these genotypes demonstrated effectiveness in protecting against the circulating rotavirus strains. However, further analysis is needed to determine the true long-term effectiveness of these vaccines; the analysis should also consider the unexpected effects of vaccinations, such as vaccine-induced diseases, herd immunity, and changes in host susceptibilities.