GUT FEELINGS: THE POTENTIAL FOR INCREASED INTUSSUSCEPTION WITH THE INTRODUCTION OF ROTAVAC INTO INDIA’S UNIVERSAL IMMUNIZATION PROGRAM

Abstract

Though the introduction of a new rotavirus vaccine, Rotavac, into India’s universal immunization program would prevent diarrheal morbidity and mortality, it may also increase the incidence of a rare intestinal obstruction called intussusception. Current rotavirus vaccines carry a risk of intussusception on the order of 1-2 excess cases per 100,000 vaccinated infants, while a previous rotavirus vaccine was withdrawn after being associated with an excess risk of 1 intussusception per 10,000 vaccinated infants. The number of intussusception cases that could be seen in India if Rotavac is added to the universal immunization program is assessed using the average baseline intussusception incidence seen in countries with comparable under-5 mortality rates and the average relative risk observed after vaccination with current rotavirus vaccines. Assuming that Rotavac doses are administered at the same levels as diphtheria-tetanus-pertussis doses currently are, then there will be 5,906 excess cases of intussusception due to rotavirus vaccination per year in India, representing an increase of 20% over baseline number of intussusceptions. Only 12-500 will be reported as adverse events through the standard reporting system, with 15-700 potentially reported through a web portal. The number reported decreases when the state-by-state vaccine coverage and surveillance data are used. The government is recommended to either strengthen both the AEFI surveillance system and existing knowledge about intussusception or focus on self-controlled case series analyses. Rotavirus vaccination risks are outweighed by potential benefits for Indian society, provided that the intussusception risk is monitored.