Rotavirus diversity among diarrheal children in Delhi, India during 2007-2012

Area of Science:

• Virology
• Pediatrics
• Public Health

Background:

• Rotavirus (RV) is a major cause of severe gastroenteritis and mortality in young children worldwide, particularly in India.
• The introduction of the indigenous rotavirus vaccine 'ROTAVAC' in India necessitates ongoing surveillance of circulating RV strains.
• Understanding the diversity of RV strains is crucial for assessing vaccine impact and efficacy.

Purpose of the Study:

• To compare the prevalence and patterns of rotavirus genotypes circulating in Delhi over a 5-year period with data from the preceding 12 years.
• To identify common and emerging rotavirus G-P combinations in Delhi.
• To provide data for monitoring the impact of rotavirus vaccination on strain diversity.

Main Methods:

• Retrospective analysis of rotavirus strains detected in clinical samples from Delhi over a 12-year period (including a recent 5-year period).
• G and P genotyping of rotavirus strains using molecular methods.
• Statistical analysis to determine the prevalence of different G and P genotypes and G-P combinations.

Main Results:

• The most common G genotypes were G1 (22.4%), G9 (25.2%), and G2 (17.2%).
• The most common P specificities were P[4] (25.5%), P[6] (20%), and P[8] (16.9%).
• G12 (14.8%) was the fourth most common G-type. Notably, G9P[4] and G2P[6] increased in prevalence.
• Sixteen different G-P combinations were identified, with G1P[8], G2P[4], G9P[8], and G12P[6] being prominent.

Conclusions:

• Delhi exhibits rich diversity in rotavirus strains, with common G and P genotypes and combinations.
• The emergence of previously rare G-P combinations like G9P[4] and G2P[6] highlights the dynamic nature of RV epidemiology.
• Continuous monitoring of rotavirus strain diversity is essential to evaluate the effectiveness of the monovalent 'ROTAVAC' vaccine and adapt public health strategies.