Challenges in conducting a community-based influenza vaccine trial in a rural community in northern India

Conducting community-based pediatric research in rural India: Experience from vadu rural health program

This paper describes unique challenges faced during conduct of community research studies in rural population of Maharashtra at Vadu Rural Health Program, Pune, India. Some of the ethical issues faced include difficulty in comprehending the informed consent by rural families with low education levels and ensuring adequate compensation for study participation without undue inducement, ensuring large number of recruitments during early infancy, ensuring adherence to intervention by care-providers, retention of participants especially in studies having long follow-ups and regulatory compliance for serious adverse event reports are major operational challenges. The delays faced in approvals from the Health Ministry Screening Committee and lack of specific regulatory guidance on community-based conduct of studies pose challenges in terms of study timelines and operational aspect of these studies. Provision of study-related information during prestudy visits, designing patient information sheets in simple language, involving the decision-making member of the family, adequate time for families for decision-making are certain measures that have been useful for effective informed consent administration. Collaboration with accredited social health activists and auxillary nurse midwives for line-listing of pregnancies and births and regular conduction of prestudy visits or community sensitization meetings have been useful for the recruitment of large number of study participants during infancy. Strategies such as provision of universal immunization, selection of field research assistants from the local population, regular home visits, and provision of medical care has been helpful in retention of the study participants. Networking with local health facilities and local government bodies has helped in the provision of medical care to the study participants and in the management of serious adverse events. Our experience can provide important learnings to other investigators from developing countries working in the domain of child health.

Efficacy of live attenuated and inactivated influenza vaccines among children in rural India: A 2-year, randomized, triple-blind, placebo-controlled trial

BACKGROUND

Influenza is a cause of febrile acute respiratory infection (FARI) in India; however, few influenza vaccine trials have been conducted in India. We assessed absolute and relative efficacy of live attenuated influenza vaccine (LAIV) and inactivated influenza vaccine (IIV) among children aged 2 to 10 years in rural India through a randomized, triple-blind, placebo-controlled trial conducted over 2 years.

METHODS AND FINDINGS

In June 2015, children were randomly allocated to LAIV, IIV, intranasal placebo, or inactivated polio vaccine (IPV) in a 2:2:1:1 ratio. In June 2016, vaccination was repeated per original allocation. Overall, 3,041 children received LAIV (n = 1,015), IIV (n = 1,010), nasal placebo (n = 507), or IPV (n = 509). Mean age of children was 6.5 years with 20% aged 9 to 10 years. Through weekly home visits, nasal and throat swabs were collected from children with FARI and tested for influenza virus by polymerase chain reaction. The primary outcome was laboratory-confirmed influenza-associated FARI; vaccine efficacy (VE) was calculated using modified intention-to-treat (mITT) analysis by Cox proportional hazards model (PH) for each year. In Year 1, VE was 40.0% (95% confidence interval (CI) 25.2 to 51.9) for LAIV and 59.0% (95% CI 47.8 to 67.9) for IIV compared with controls; relative efficacy of LAIV compared with IIV was -46.2% (95% CI -88.9 to -13.1). In Year 2, VE was 51.9% (95% CI 42.0 to 60.1) for LAIV and 49.9% (95% CI 39.2 to 58.7) for IIV; relative efficacy of LAIV compared with IIV was 4.2% (95% CI -19.9 to 23.5). No serious adverse vaccine-attributable events were reported. Study limitations include differing dosage requirements for children between nasal and injectable vaccines (single dose of LAIV versus 2 doses of IIV) in Year 1 and the fact that immunogenicity studies were not conducted.

CONCLUSIONS

In this study, we found that LAIV and IIV vaccines were safe and moderately efficacious against influenza virus infection among Indian children.

TRIAL REGISTRATION

Clinical Trials Registry of India CTRI/2015/06/005902.