Herd immunity after two years of the universal mass vaccination program against rotavirus gastroenteritis in Austria

Austria was the first country in Europe implementing a universal mass vaccination program against rotavirus gastroenteritis (RV-GE) for all infants nationwide. Epidemiological data from a hospital based surveillance system show that incidence rates of children hospitalized with RV-GE decreased in 2009 compared to 2008 and compared to the prevaccination period 2001-2005. Decreasing hospitalization-rates from RV-GE were observed in children of all age groups, even in those not eligible for vaccination according to their age, suggesting herd immunity induced by universal mass vaccination against RV-GE. In 2009 the disease burden was highest in children below three months of age stressing the importance of the early start of the immunization course.     

Acute gastroenteritis hospitalizations after implementation of universal mass vaccination against rotavirus

BackgroundEstonia implemented rotavirus universal mass vaccination (RV UMV) in July 2014. We aimed to describe changes in acute gastroenteritis (AGE) hospitalization during RV seasons before (2007–2013) and after (2015–2018) RV UMV and compare patient profile of hospitalized AGE patients aged 0–18 years during first two consecutive RV seasons 2015 vs 2016.MethodsWe described AGE hospitalization patterns pre-and post-vaccine era using Estonian Health Insurance Fund (HIF) database. During a two-year observational multicenter study in seven Estonian hospitals from 01st of February 2015 to 30th August 2016 we assessed patient profile of all patients who met pre-determined AGE criteria.ResultsIn post-vaccine era AGE hospitalization rate decreased from 10 to 8 per 1000 population (RR 0.81, 95% CI 0.79–0.83) compared to pre-vaccine era. Decreased RV seasonal activity, 81% (95% CI 77–84) and 55% (95% CI 52–58) reduction of rotavirus gastroenteritis (RVGE) hospitalization among age groups <1 and 1–4, respectively and upsurge of norovirus gastroenteritis (NoVGE) hospitalizations (RR = 1.8; 95% CI 1.6–1.9) was seen.In the multicenter observational study, among 2249 AGE patients hospitalized median age of RVGE patients increased from 2 to 3 years (p < 0.01) and duration of hospital stay decreased among RVGE, NoVGE and other GE patients during two consecutive RV seasons. According to Vesikari Clinical Severity Scoring System statistically significant change of severity score distribution in two RV seasons was seen (p < 0.001) with trend towards less severe AGE hospitalizations; 82.5% vs 70.5% severe cases in 2015 vs 2016, respectively.ConclusionRV UMV lead to immediate and sustainable reduction of hospitalizations due to RVGE in children aged <4 years and reduction of overall AGE accompanied with the decrease in the severity of hospitalized children.     

Distribution of rotavirus genotypes in Japan from 2015 to 2018: Diversity in genotypes before and after introduction of rotavirus vaccines

BackgroundDiversity in group A rotavirus (RVA) strains after introduction of RV-vaccines remains an emerging concern worldwide. In this study, we investigated the prevalence and distribution of RVA genotypes in Japanese children with acute gastroenteritis (AGE) from 2015 to 2018. In addition, a comparison of the genotypes in pre-vaccination (2006–2012) and post-vaccination (2012–2018) periods was conducted to understand the impact of these vaccines on genotype distribution.MethodsFecal samples were collected regularly from outpatient clinics in six localities: Hokkaido, Tokyo, Shizuoka, Osaka, Kyoto, and Saga. RVA were screened and genotyped by RT-PCR and sequence-based genotyping.ResultsDuring the period 2015–2018, RVA was detected in 307 (19.7%) samples out of 1557 specimens: 29.9% (95% CI: 25.8% to 34.3%), 17.9% (95% CI: 14.7% to 21.5%), and 13% (95% CI: 10.3% to 16.0%) were detected RVA-positive in 2015–2016, 2016–2017 and 2017–2018, respectively. The average detection of RVA in pre-vaccination (2006–2012) and post-vaccination (2012–2018) era remained almost similar (18%-20%). The G2P[4]I2 (52.1%, 95% CI: 43.5%-60.6%) remained the most common genotype in 2015–2016, whereas G8P[8]I2 (55.9%, 95% CI: 45.2%-66.2%) dominated in 2016–2017. In 2017–2018, G9P[8]I2 (42.0%, 95% CI: 30.5%-53.9%) prevailed, followed by G9P[8]I1 (23.0%, 95% CI: 14.0%-34.2%). The detection rate of some common genotypes of pre-vaccination era like G1P[8] and G3P[8] has been reduced after introduction of RV-vaccine, whereas genotypes that were sporadic before the introduction of vaccines like G2P[4], G2P[8], G9P[8] and G8P[8] were emerged/reemerged in post-vaccination period.ConclusionsOur study presented the diversity in circulating RVA genotypes in Japan before and after introduction of RV-vaccines. Sudden emergence of DS-1-like (I2) unusual strains in post-vaccination era remains alarming. Continuous monitoring of RVA genotypes is therefore indispensable to refine future vaccine strategy.     

Incidence and cost of rotavirus hospitalizations in Denmark

In anticipation of licensure and introduction of rotavirus vaccine into the western market, we used modeling of national hospital registry data to determine the incidence and direct medical costs of annual rotavirus-associated admissions over >11 years in Denmark. Diarrhea-associated hospitalizations coded as nonspecified viral or presumed infectious have demonstrated a marked winter peak similar to that of rotavirus-associated hospitalizations, which suggests that the registered rotavirus-coded admissions are grossly underestimated. We therefore obtained more realistic estimates by 2 different models, which indicated 2.4 and 2.5 (for children <5 years of age) and 4.9 and 5.3 (for children <2 years of age) rotavirus-associated admissions per 1,000 children per year, respectively. These admissions amount to associated direct medical costs of US $1.7-1.8 million per year. Using 2 simple models to analyze readily available hospital discharge data resulted in more consistent and reliable estimates.     

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

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

Knowledge,attitudes, beliefs,and behaviors of parents and healthcare providers before and after implementation of a universal rotavirus vaccination program

ObjectiveIn Canada, rotavirus vaccine is recommended for all infants, but not all provinces/territories have publicly funded programs. We compared public and healthcare provider (HCP) knowledge, attitudes, beliefs, and behaviors in a province with a public health nurse-delivered, publicly funded rotavirus vaccination program to a province with a publicly funded, physician-delivered program. A third province with no vaccination program acted as a control.DesignInformation about knowledge, attitudes, beliefs, and behaviors of parents whose children were eligible for the universal program and healthcare providers responsible for administering the vaccine were collected through the use of two validated surveys distributed in public health clinics, physicians’ offices, and via e-mail. Early and postvaccine-program survey results were compared.ResultsA total of 722 early implementation and 709 postimplementation parent surveys and 180 early and 141 postimplementation HCP surveys were analyzed. HCP and public attitudes toward rotavirus vaccination were generally positive and didn’t change over time. More parents postprogram were aware of the NACI recommendation and the vaccination program and reported that their healthcare provider discussed rotavirus infection and vaccine with them. Prior to the program across all sites, more physicians than nurses were aware of the national recommendation regarding rotavirus vaccine. In the postprogram survey, however, more nurses were aware of the national recommendation and their provincial universal rotavirus vaccination program. Nurses had higher knowledge scores than physicians in the postprogram survey (p < 0.001). Parents of young infants were also more knowledgeable about rotavirus and rotavirus vaccine in the two areas where universal programs were in place (p < 0.001).ConclusionsImplementation of a universal rotavirus vaccination program was associated with an increase in knowledge and more positive attitudes toward rotavirus vaccine amongst parents of eligible infants. Nurses involved in a public health-delivered vaccination program were more knowledgeable and had more positive attitudes toward the vaccine than physicians in a jurisdiction where vaccine was physician-delivered.     

Effects of rotavirus vaccine on all-cause acute gastroenteritis and rotavirus hospitalizations in Israel: A nationwide analysis

BackgroundIn December 2010, the pentavalent rotavirus vaccine (RotaTeq) was added to the national immunization program in Israel. The study aim was to examine national reductions in all-cause acute gastroenteritis (AGE) and rotavirus gastroenteritis (RVGE) hospitalizations among children aged 0–59 months following the introduction of universal rotavirus immunization in Israel.MethodsWe extracted data from the Israel National Hospital Discharge Database. Hospitalization rates were calculated by dividing the annual number of all-cause AGE and RVGE hospitalizations by the number of children aged 0–59 months residing Israel. To assess rate reductions, we compared the mean hospitalization rate for the pre-vaccine years (2002–2008) with that for the universal vaccination years (2011–2017). Interrupted time-series analyses were undertaken. During 2008–2010 rotavirus vaccines were partially available.ResultsA total of 131,116 AGE hospitalizations were reported, of which 13,111 (10.0%) were coded as RVGE hospitalizations. The average annual all-cause AGE hospitalization rate during the pre-vaccine period was 147.9 (95% CI 146.7–149.0) per 10,000 children aged 0–59 months, and declined by 38.7–53.0% during the universal vaccination years. The average annual pre-vaccine RVGE hospitalization rate was 16.9 (95% CI 16.5–17.3) per 10,000 children, and declined by 89.1% during 2016–2017.Findings from interrupted time-series analyses showed significant impact of introducing universal rotavirus immunization on the declines of all-cause AGE and RVGE hospitalizations rates. A multivariable Autoregressive Integrated Moving Average model showed that the variable “immunization period” was a significant predictor of RVGE hospitalizations (t = 7.3, p < 0.001) for the universal vaccination years.The declines in hospitalizations rates of all-cause AGE were lower among Arab children compared to Jewish children, but the declines in RVGE rates were similar between the groups.ConclusionsNational hospitalization data demonstrated substantial and consistent reductions in all-cause AGE and RVGE hospitalizations following the implementation of universal rotavirus vaccination program.     

Rotavirus incidence and genotype distribution before and after national rotavirus vaccine introduction in Belgium

Rotarix™ was introduced into the Belgian market in 2006 and RotaTeq™ in 2007, quickly reaching more than 85% vaccine coverage of all newborns in Belgium. The incidence of rotavirus gastroenteritis has been monitored in the Gasthuisberg University Hospital (GUH), Belgium since 1986, and since 1999 the genotypes of circulating rotavirus strains have been determined. The average percentage of rotavirus positive cases out of all hospitalized gastro-enteritis cases tested (>95% of these cases are younger than 5 years old) at the GUH between 1986 and 2006 was 19.0%. This percentage dropped to 12.4%, 9.6% and 6.4% in the three seasons post vaccine introduction (2006–2009), which is a decline of 34.7%, 49.4% and 66.3% respectively. In addition the rotavirus season was found to be shortened and delayed. The prevalence of the G2 genotype sharply increased in the 2006–2007 rotavirus season compared to the previous seasons and remained high (30–40%) in the 2007–2008 and 2008–2009 seasons. Rotavirus vaccines have strongly reduced the number of children hospitalized due to a rotavirus infection at the GUH; it is however unclear if the predominance of G2 genotypes is related to the vaccine introduction, or if this is attributable to normal genotype fluctuations. Continued surveillance will be pivotal to answer this question in the future.     

Sustained low hospitalization rates after four years of rotavirus mass vaccination in Austria

This hospital based surveillance study evaluates the effects of the rotavirus mass vaccination program, which was initiated in Austria in August 2007. Since then, incidence rates of rotavirus hospitalizations in children <15 years of age have decreased by 70% and 64% in 2010 and 2011 compared to the pre-vaccination era (2001–2005). Incidence rates were highest in children <90 days of age, highlighting the importance of the early start of active rotavirus immunization. In children between 2 and 3.5 years in 2011, who were in the second and third year after vaccination in the universal mass vaccination program, incidence rates remained low suggesting sustained protection after vaccination up to three years. In the years 2010 and 2011, field effectiveness of the vaccines was between 79% and 96%, depending on the assumptions made for children without information on vaccination history. From genotyping an increase of the prevalence of G2P[4] in children with breakthrough infection (disease despite vaccination) can be suspected. The rate of severe adverse events was 1.3–1.5 per 10⁻⁵ administered doses of rotavirus vaccines and no death, intussusception or Kawasaki disease was reported in 2010 and 2011 following rotavirus vaccination.     

Rotavirus genotypes circulating in Ontario,Canada, before and after implementation of the rotavirus immunization program

Background and objectivesOntario introduced a universal publicly-funded group A rotavirus (RVA) immunization program in August 2011, using monovalent vaccine. RVA immunization programs have decreased the incidence of RVA acute gastroenteritis in many countries but it is unclear if it will contribute to the emergence of certain genotypes. We monitored RVA trends and genotypes in Ontario before and after implementation of the publicly-funded immunization program.MethodsRVA detection was conducted at Public Health Ontario Laboratories from January 2009 to December 2011 (pre-program period) and January 2012 to October 2015 (publicly-funded RVA immunization program period) and number of RVA-positive specimens and percent positivity were analysed. A convenience sample of RVA-positive stool specimens, from September 2010 to December 2011 (pre-program period) and January 2012 to June 2013 (program period), were genotyped using heminested PCR. A literature review on the burden of illness from emergent genotype was performed.ResultsStool specimens showed a significant decrease in RVA percent positivity from the 36 month pre-program period (14.4%; 1537/10700) to the 46 month program period (6.1%; 548/9019). An increase in the proportion of RVA G10 among genotyped specimens, associated with five different P genotypes, from the pre-program (6.3%; 13/205) to the program (31.5%; 40/127) period was observed. Our literature review identified approximately 200 G10-positive human stool specimens from 16 different countries.ConclusionsThis study documented a decrease in the number of RVA-positive specimens and percent positivity after implementation of the immunization program. An unexpected increase in the proportion of RVA G10 was detected following program introduction. Ongoing RVA surveillance is important in evaluating both the long-term impact of immunization and emergence of RVA genotypes.     

深圳市宝安区5岁以下婴幼儿轮状病毒胃肠炎的社区干预研究

目的 了解深圳市宝安区5岁以下婴幼儿看护人轮状病毒胃肠炎的知信行,评价轮状病毒胃肠炎的社区干预效果。 方法 在深圳市宝安区辖区内选取轮状病毒发病率、人口特征、医疗水平和经济水平接近且地理位置不相邻的两个街道分别作为干预街道和对照街道。对干预组辖区内的医疗场所规范其消毒处理,在医疗场所和社区内进行轮状病毒胃肠炎的健康宣教。调查干预前后两街道的婴幼儿看护人轮状病毒胃肠炎的知信行,干预后两街道儿童的轮状病毒胃肠炎的发病率。 结果 干预街道看护人干预前后轮状病毒胃肠炎知识知晓率(χ²=14.897,P<0.001)、看护人使用开水煮的方式对婴幼儿奶具消毒的比例(χ²=7.978,P=0.046)、消毒餐具的频率(Z=2.358,P=0.018)、使用开水煮的方式消毒餐具的比例有提高(χ²=20.608,P<0.001)。干预后,干预组疫苗接种的比例高于对照组(χ²=4.334,P=0.037)。流行季节过后,干预街道RVGE患病率较对照组低,差异有统计学意义(χ²=4.927,P=0.026)。 结论 通过规范医疗场所的消毒处理;加大医疗场所和社区的健教宣传,提高了婴幼儿看护人对轮状病毒胃肠炎的知识水平、促进其形成健康的看护习惯,可降低婴幼儿轮状病毒胃肠炎的发病率,为轮状病毒胃肠炎的社区干预提供可行方法。     

Racial disparities in diarrhea-associated hospitalizations among children in five US States,before and after introduction of rotavirus vaccine

Racial differences in diarrheal disease have not been systematically examined, and the impact of rotavirus vaccine on these differences has not been assessed. We compared diarrhea-associated hospitalizations by race/ethnicity among children <5 years pre- (2000–2006) and post- (2007 and 2008) rotavirus vaccine introduction in five US states. Pre-vaccine hospitalization rates were greater among whites versus blacks and Hispanics. However, black (versus non-black) infants <6 months and white (versus non-white) children ≥1 year had higher rates. In 2008, racial disparities for children 12–35 months resolved, but higher hospitalization rates among black infants <6 months persisted, highlighting the need for timely vaccination.     

Effectiveness of rotavirus vaccines in preventing cases and hospitalizations due to rotavirus gastroenteritis in Navarre, Spain

Two rotavirus vaccines have been available since 2006. This study evaluates the effectiveness of these vaccines using a test-negative case-control design in Navarre, Spain. We included children 3-59 months of age who sought medical care for gastroenteritis and for whom stool samples were taken between January 2008 and June 2011. About 9% had received the pentavalent vaccine (RotaTeq) and another 8% received the monovalent vaccine (Rotarix). Cases were the 756 children with confirmed rotavirus and controls were the 6036 children who tested negative for rotavirus. Thirty-five percent of cases and 9% of controls had required hospitalization (p < 0.0001). The adjusted effectiveness of complete vaccination was 78% (95% CI: 68-85%) in preventing rotavirus gastroenteritis and 83% (95% CI: 65-93%) in preventing hospitalization for rotavirus gastroenteritis. No differences between the two vaccines were detected (p = 0.4523). Both vaccines were highly effective in preventing cases and hospital admissions in children due to rotavirus gastroenteritis.     

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

Background

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

Evidence of reduction of rotavirus diarrheal disease after rotavirus vaccine introduction in national immunization programs in the African countries: Report of the 11th African rotavirus symposium held in Lilongwe,Malawi

The 11^th African Rotavirus Symposium was held in Lilongwe, Malawi from May 28^th to 30^th 2017. Over 270 delegates (73% from Africa) from 40 countries of which 30 (75%) were from African countries attended the symposium. Participants in this symposium included research scientists, clinicians, immunization managers, public health officials, policymakers and vaccine manufacturers. At the time of the symposium, 38 of the 54 (70%) countries in Africa had introduced rotavirus vaccines into their national immunization schedules. Delegates shared progress from rotavirus surveillance and vaccine impact monitoring, demonstrating the impact of the vaccine against rotavirus diarrheal hospitalizations. Data supported the beneficial effect and safety of WHO pre-qualified available vaccines up to 2017 (RotaTeq, Rotarix). This symposium highlighted the dramatic impact of the rotavirus vaccination, called for urgent adoption of these vaccines in remaining countries, particularly those with high disease burden and large birth cohorts (e.g. Nigeria, Democratic Republic of Congo) to attain the full public health benefits of rotavirus vaccination in Africa.     

Diarrhoea-related hospitalizations in children before and after implementation of monovalent rotavirus vaccination in Mexico

Objective

To assess, by socioeconomic setting, the effect of nationwide vaccination against species A rotavirus (RVA) on childhood diarrhoea-related hospitalizations in Mexico.

Methods

Data on children younger than 5 years who were hospitalized for diarrhoea in health ministry hospitals between 1 January 2003 and 31 December 2011 were collected from monthly discharge reports. Human development indexes were used to categorize the states where hospitals were located as having generally high, intermediate or low socioeconomic status. Annual rates of hospitalization for diarrhoea – per 10 000 hospitalizations for any cause – were calculated. Administrative data were used to estimate vaccine coverage.

Findings

In the states with high, intermediate and low socioeconomic status, coverage with a two-dose monovalent RVA vaccine – among children younger than 5 years – had reached 93%, 86% and 71%, respectively, by 2010. The corresponding median annual rates of hospitalization for diarrhoea – per 10 000 admissions – fell from 1001, 834 and 1033 in the “prevaccine” period of 2003–2006, to 597, 497 and 705 in the “postvaccine” period from 2008 to 2011, respectively. These decreases correspond to rate reductions of 40% (95% confidence interval, CI: 38–43), 41% (95% CI: 38–43) and 32% (95% CI: 29–34), respectively. Nationwide, RVA vaccination appeared to have averted approximately 16 500 hospitalizations for childhood diarrhoea in each year of the postvaccine period.

Conclusion

Monovalent RVA vaccination has substantially reduced childhood diarrhoea-related hospitalizations for four continuous years in discretely different socioeconomic populations across Mexico.     

Nosocomial rotavirus gastroenteritis in a Canadian paediatric hospital: incidence, disease burden and patients affected

Rotavirus is a well-recognised nosocomial pathogen in paediatric settings. Although rotavirus gastroenteritis is a vaccine-preventable disease, there is currently no publicly funded programme in Canada. The objective of this study was to inform rotavirus vaccination strategy by determining the incidence of nosocomial rotavirus gastroenteritis (NRVGE), estimating the burden of disease and characterising the patients affected. We performed a retrospective cohort study of all NRVGE cases over a period of 10 years in a Canadian tertiary-care paediatric hospital. Cases (N = 214) were identified by the hospital's prospective surveillance programme for nosocomial infections. The incidence was 0.5 per 1,000 patient-days (95% confidence interval: 0.43-0.57) with no significant decline over the 10-year period. The infection rate per hospital day was highest among patients with a hospital stay of > 5 days. A chronic underlying medical condition was present in 126 patients (59%), was often associated with previous hospitalisation, and was identifiable early in life for 95 patients (44%). Rehydration was required for 132 (62%) patients and was intravenous in 98 (46%). Twenty-six patients (12%) required readmission, for a median of four days, for NRVGE that occurred after discharge. Nosocomial rotavirus infection continues to be an important problem in paediatric hospitals, predominantly for children with underlying medical conditions requiring recurrent and prolonged hospitalisation. A rotavirus immunisation programme targeted at vulnerable patients, such as infants with congenital pathology and low birth weight, requires assessment in Canada and other countries that have not introduced universal rotavirus immunisation.     

全面二孩政策实施前后广东省流动妇女二孩生育意愿研究

目的 了解全面二孩政策实施前后广东省已婚流动妇女二孩生育意愿并分析全面二孩政策对其二孩生育意愿的影响。方法 基于2014年和2016年全国流动人口动态监测调查广东省数据,采用倾向性评分加权法均衡不同年度调查对象的协变量差异后,使用多分类Logistic模型探索全面二孩政策对已婚流动妇女二孩生育意愿的影响。结果 全面二孩政策实施后提升了流动妇女的二孩生育意愿,且对于政策实施前不符合生育二孩政策的人群,政策效果更明显（OR_不符合=5.35,95%CI：4.55~6.29;OR_符合=1.61,95%CI：1.36~1.90）。政策实施后流动妇女不愿意再生育的原因主要与经济因素和婴幼儿照护压力有关。结论 全面二孩政策实施后已婚流动妇女的二孩生育意愿明显提升,但仍有待提高。今后应积极探索缓解生育经济负担和发展婴幼儿照护服务在提升二孩生育意愿中的作用。