ROTAVIRUS GENOTYPES CIRCULATING IN BRAZIL, 2007-2012: IMPLICATIONS FOR THE VACCINE PROGRAM

Area of Science:

• Public Health
• Virology
• Epidemiology

Background:

• Universal rotavirus (RV) vaccination programs were established in Brazil, creating a new public health scenario.
• Understanding RV strain dynamics is crucial for monitoring vaccine impact and public health strategies.

Purpose of the Study:

• To report five-year surveillance data (2007-2012) of G- and P-type RV strains in Brazil.
• To analyze changes in RV incidence, seasonality, and genotype distribution following vaccination.

Main Methods:

• Investigated 6,196 fecal specimens using ELISA and RT-PCR.
• Analyzed RV detection rates, seasonality, age distribution, and G/P genotype profiles.

Main Results:

• Rotavirus (RV) was detected in 19.1% of cases. The incidence peak shifted from June-August to September.
• RV was less frequent in children ≤ 5 years (19.5%) compared to older children/adolescents (6-18 years, 40.6%).
• Genotype distribution varied annually: G2P[4] (2007-2010), G9P[8] (2011), and G12P[8] (2012). Unusual and rare strains were also identified.

Conclusions:

• Widespread RV vaccination may alter seasonal patterns and affect older age groups.
• G2P[4] emergence appears globally driven, while G12 is emerging in Brazil.
• Rapidly changing RV genotypes indicate a dynamic co-circulation of wild-type strains in Brazil.