Review of Over 15 Years Postmarketing Safety Surveillance Spontaneous Data for the Human Rotavirus Vaccine (Rotarix) on Intussusception

A randomized, double-blind, placebo-controlled phase I clinical trial of rotavirus inactivated vaccine (Vero cell) in a healthy adult population aged 18-49 years to assess safety and preliminary observation of immunogenicity

We conducted a phase I, randomized, double-blind, placebo-controlled trial including healthy adults in Sui County, Henan Province, China. Ninety-six adults were randomly assigned to one of three groups (high-dose, medium-dose, and low-dose) at a 3:1 ratio to receive one vaccine dose or placebo. Adverse events up to 28 days after each dose and serious adverse events up to 6 months after all doses were reported. Geometric mean titers and seroconversion rates were measured for anti-rotavirus neutralizing antibodies using microneutralization tests. The rates of total adverse events in the placebo group, low-dose group, medium-dose group, and high-dose group were 29.17 % (12.62 %-51.09 %), 12.50 % (2.66 %-32.36 %), 50.00 % (29.12 %-70.88 %), and 41.67 % (22.11 %-63.36 %), respectively, with no significant difference in the experimental groups compared with the placebo group. The results of the neutralizing antibody assay showed that in the adult group, the neutralizing antibody geometric mean titer at 28 days after full immunization in the low-dose group was 583.01 (95 % confidence interval [CI]: 447.12-760.20), that in the medium-dose group was 899.34 (95 % CI: 601.73-1344.14), and that in the high-dose group was 1055.24 (95 % CI: 876.28-1270.75). The GMT of serum-specific IgG at 28 days after full immunization in the low-dose group was 3444.26 (95 % CI: 2292.35-5175.02), that in the medium-dose group was 6888.55 (95 % CI: 4426.67-10719.6), and that in the high-dose group was 7511.99 (95 % CI: 3988.27-14149.0). The GMT of serum-specific IgA at 28 days after full immunization in the low-dose group was 2332.14 (95 % CI: 1538.82-3534.45), that in the medium-dose group was 4800.98 (95 % CI: 2986.64-7717.50), and that in the high-dose group was 3204.30 (95 % CI: 2175.66-4719.27). In terms of safety, adverse events were mainly Grades 1 and 2, indicating that the safety of the vaccine is within the acceptable range in the healthy adult population. Considering the GMT and positive transfer rate of neutralizing antibodies for the main immunogenicity endpoints in the experimental groups, it was initially observed that the high-dose group had higher levels of neutralizing antibodies than the medium- and low-dose groups in adults aged 18-49 years. This novel inactivated rotavirus vaccine was generally well-tolerated in adults, and the vaccine was immunogenic in adults (ClinicalTrials.gov number, NCT04626856).

Attitudes and Beliefs towards Rotavirus Vaccination in a Sample of Italian Women: A Cross-Sectional Study

(1) Background: Rotavirus is the leading cause of severe diarrhea and dehydration in infants and young children worldwide. Despite the proven benefits of vaccination, vaccine hesitancy and refusal remains a significant barrier to achieving high vaccination coverage in many countries, such as Italy. (2) Methods: An online survey was conducted among women aged between 18 and 50 years from Abruzzo Region, Italy. The survey was composed of two main sections: demographic characteristics and attitudes and knowledge about rotavirus vaccination, based on a five-point Likert scale. Logistic regression analysis was performed to evaluate factors associated with willingness to get the rotavirus vaccination. (3) Results: A total of 414 women were enrolled in the study. Women who were unaware of rotavirus more frequently had a lower education level (university degree 62.5% vs. 78.7%, p = 0.004) and reported having no children (p < 0.001). About half of the enrolled women thought that rotavirus infection is dangerous (190, 55.6%) and that rotavirus can cause a serious illness (201, 58.8%). Regarding associated factors, women informed by a physician were more likely get a vaccination compared to women informed by friends or relatives (OR 34.35, 95% CI 7.12-98.98, p < 0.001). (4) Conclusions: The present study showed low levels of knowledge and attitudes towards rotavirus vaccination. These results highlight the need for developing and improving additional public education programs for parents.