8 per cent infectious disease outbreaks during 2018-2023 spread from animals to humans, study says

The Hindu

a day ago

Zoonotic outbreaks consistently peaked during June, July, and August, researchers from the Indian Council of Medical Research-National Institute of Epidemiology, Chennai said.
Typically, about seven zoonotic outbreaks -- also sometimes called 'spillover events' -- occurred in a month, and such instances significantly increased over the years, specifically, post-pandemic, the study published in The Lancet Regional Health Southeast Asia journal found.
Study highlights
The team analysed a total of 6,948 outbreaks reported under the Integrated Disease Surveillance Program (IDSP) to identify trends.
Of these, 583 (8.3 per cent) were zoonotic -- Japanese encephalitis was found to account for 29.5 per cent of zoonotic outbreaks, followed by leptospirosis (18.7 per cent) and scrub typhus (13.9 per cent).
Region-wise, the northeast part of the country contributed 35.8 per cent of zoonotic disease outbreaks, followed by the southern (31.7 per cent) and western regions (15.4 per cent), the researchers found.
They added that late reporting of disease outbreaks has declined over the years -- 52.6 per cent in 2019, 40.9 per cent in 2021, and 5.2 per cent in 2023. Overall, a third of the outbreaks during the study period were reported late, the team said.
"Of the 6948 outbreaks reported in IDSP, 583 (8.3 per cent) were zoonotic, with a median of seven monthly zoonotic outbreaks. Outbreaks significantly increased over the years," the authors wrote.
Further research required
The researchers said that while outbreaks of measles, chickenpox, and dengue have been individually analysed, zoonotic events from the national-level infectious disease surveillance system have not been comprehensively examined.
A lack of analysis of geographical patterns and documentation of reporting delays hindered evidence-based decision-making and targeted interventions, the team said. "Critical gaps in weekly outbreak reports were identified, particularly the lack of follow-up documentation. To address these gaps, we recommend strengthening disease-specific surveillance systems in hotspot regions," the authors concluded.