Effectiveness of rotavirus vaccine following introduction in the childhood immunization program in Northeast India.

Background: Rotavirus diarrhoea is a major cause of mortality and morbidity in children under five years of age. The WHO has recommended vaccination against this agent especially in countries with high mortality rates. As India accounts for almost a quarter of worldwide rotaviral diarrhoea cases, the government has introduced indigenously manufactured vaccines in the national immunization schedule which has been implemented in four phases. This study was conducted to assess the effectiveness of the vaccine used in the national immunization program in the state of Manipur in North-east India.

Methods: A test negative study design was used comparing rotavirus positive diarrhoeal children to rotavirus negative diarrhoeal children. All children ≤ 5 years presenting with acute diarrhoea were enrolled in the study and antigen detection enzyme-immuno assay was done to detect presence of rotavirus. All rotavirus positive patients were taken as cases and compared with rotavirus negative controls.

Results: 63 rotavirus positive cases and 121 rotavirus negative controls were enrolled in the study. Vaccination rate among cases was significantly lower than controls (31.7% vs 68.6%, p < .001). Vaccine effectiveness of completed vaccination series was found to be 94% against rotaviral infection and 98.1% against severe disease and need for hospitalization.

Conclusion: Current rotaviral vaccine used in the national immunization schedule of India is effective in preventing rotaviral diarrhoea in the state of Manipur. Sustained vaccination will reduce the mortality and morbidity of rotaviral diarrhoea in this region.