Rotavirus Strain Distribution before and after Introducing Rotavirus Vaccine in India

Area of Science:

• Pediatric Infectious Diseases
• Vaccinology
• Public Health Surveillance

Background:

• Rotavirus is a leading cause of severe childhood gastroenteritis globally.
• The introduction of rotavirus vaccines aims to reduce disease burden.
• Monitoring vaccine impact on circulating strains is crucial for public health.

Purpose of the Study:

• To evaluate the impact of the indigenous monovalent rotavirus vaccine (Rotavac) on rotavirus positivity and genotypes in India.
• To assess changes in rotavirus epidemiology following vaccine introduction.
• To inform ongoing vaccination strategies and surveillance efforts.

Main Methods:

• Hospital-based surveillance for acute gastroenteritis in children under 5 years.
• Detection of group A rotavirus using enzyme immunoassay.
• Genotyping of rotavirus strains via RT-PCR.

Main Results:

• Rotavirus proportion of diarrhea hospitalizations decreased significantly post-vaccine introduction (56-29.4% to 34-12%).
• Predominant G1P[8] strain shifted to G3P[8] after vaccination.
• Increased detection of mixed rotavirus genotypes observed post-vaccination.

Conclusions:

• Rotavac demonstrated a significant reduction in rotavirus hospitalizations.
• Vaccination altered circulating rotavirus genotypes, necessitating ongoing surveillance.
• Long-term monitoring is essential to understand vaccine's immuno-epidemiological effects.