Do Rotavirus Strains Affect Vaccine Effectiveness? A Systematic Review and Meta-analysis

Area of Science:

• Vaccinology
• Epidemiology
• Public Health

Background:

• Rotavirus infection causes over 215,000 deaths annually from severe childhood diarrhea.
• Concerns exist regarding the effectiveness of rotavirus vaccines (RV1 and RV5) against non-vaccine strains.
• This study evaluated vaccine effectiveness against homotypic and heterotypic rotavirus strains.

Purpose of the Study:

• To estimate the vaccine effectiveness (VE) of RV1 and RV5 against severe rotavirus gastroenteritis.
• To compare VE against vaccine (homotypic) and non-vaccine (partially and fully heterotypic) strains.
• To analyze VE differences across various income settings.

Main Methods:

• A systematic review and meta-analysis of 31 case-control studies (N=27,293) were conducted.
• Studies were published between 2006 and 2020.
• A random-effects regression model was employed for analysis.

Main Results:

• In high-income countries, RV1 VE was 10% lower against heterotypic strains compared to homotypic strains.
• In middle-income countries, RV1 VE showed a 14-16% reduction against heterotypic strains.
• RV5 VE differences were less pronounced, with limited data from low-income countries.

Conclusions:

• Rotavirus vaccine effectiveness (RV1 and RV5) is somewhat lower against non-vaccine strains.
• Ongoing surveillance is essential for long-term monitoring of rotavirus strain replacement.
• Special attention is needed for low-income settings due to limited available data.