Fatal surge: Kerala health data reveals fourfold increase in rat fever deaths

KOZHIKODE: Kerala is witnessing a sharp rise in leptospirosis cases, with state health department figures indicating that fatalities have more than quadrupled over the last five years compared to the 2016–2020 period. According to health department data, the state recorded 23,953 cases and 1,455 deaths between 2021 and 2025, a significant surge from the 7,447 cases and 319 deaths reported in the preceding five years. The case fatality rate has also climbed from 4.2% to 6% during this timeframe.

Public health officials suggest that while attention has been heavily diverted toward managing outbreaks of dengue, shigella, and malaria, leptospirosis prevention efforts have not received the necessary priority. This lapse in focus is believed to have contributed to the rising infection rates.

Data shows that while case numbers remained lower during the COVID-19 lockdown, the incidence of the disease spiked sharply once normal activity resumed. Health experts have identified worsening environmental pollution as a primary driver of the spread. Recent findings also indicate that the disease is now affecting even bedridden patients, highlighting the pervasiveness of the risk.

The infection, transmitted by the bacteria Leptospira, spreads through contact with water—such as drains, ponds, farmlands, and fields—contaminated by the urine of infected animals, particularly rats. Officials note that while sunlight and running water can help neutralize the bacteria, stagnant, polluted water remains a persistent threat.

"Stagnant, contaminated water is the core issue," said Dr. Arun Zachariah, District Animal Husbandry Officer. "We must prioritize pollution control and ensure the public avoids contact with potentially contaminated sources."

Dr. Arun urged citizens to remain vigilant, emphasizing the importance of animal vaccination and rat control measures. He advised that individuals who experience symptoms such as high fever, severe headache, muscle pain, or vomiting must seek medical treatment immediately.

As of June 23, 2026, the state has already reported 1,531 cases and 56 deaths for the current year.