Trial Title: A Prospective Cohort Study To Compare The Burden Of Medically Attended and Community LRTI In Infants And Children Under 5 Years Of Age and adults (16-60 years) In India
Primary Objectives:
* To determine the population-based epidemiology, clinical features, and mortality of respiratory syncytial virus (RSV) lower respiratory tract illness (LRTI) in infants, children under 5, and adults (16-60 years) in rural India.
* To calculate the incidence of RSV LRTI classifications (non-severe, severe, very severe, hospitalization, and mortality) per 1,000 child/adult years of observation.
Secondary Objectives:
• To determine the population-based epidemiology of human metapneumovirus (hMPV), SARS-CoV-2, and influenza LRTI in the same cohort.
Study Design \& Methodology:
* Type: Active surveillance, prospective longitudinal cohort study.
* Setting: 30 villages in the Melghat region of Maharashtra, India, characterized by high infant and adult mortality rates.
* Participants: All children under 5 years of age and adults aged 16-60 years residing in the study villages, including all newborns entering the cohort during the study period.
* Procedures: \* Community Surveillance: Trained Village Health Workers (VHWs) will conduct weekly home visits to monitor respiratory health and identify potential LRTI cases.
* Clinical Assessment: Supervisors will verify reported LRTI cases within 24 hours using standardized WHO classifications (non-severe, severe, and very severe pneumonia).
* Medical Facility Monitoring: Hospital-based counselors will monitor all LRTI-related outpatient visits and hospitalizations from the study villages.
* Sample Collection: Nasopharyngeal (NP) swabs will be collected from all identified LRTI cases (community and facility-based) and from any participant who dies within 15 days of an LRTI diagnosis.
* Laboratory Testing: 2,000 samples will undergo real-time PCR screening and subtyping for RSV, hMPV, SARS-CoV-2, and influenza at the National Institute of Virology, Pune.
* Mortality Investigation: For all participant deaths, a standardized verbal autopsy will be conducted to determine if LRTI was the cause of death.
Statistical Plan:
* Incidence rates and 95% confidence intervals will be calculated and severity category.
* Results will be stratified by age, sex, and socioeconomic status
* Multivariate analysis will be used Study Duration: 48 months total, including 36 months of active surveillance