Why is Kerala facing high leptospirosis mortality? | Explained
The story so far: Leptospirosis is a tropical zoonotic disease — bacterial systemic infection caused by pathogenic Leptospira — which is highly integrated with an
The story so far: Leptospirosis is a tropical zoonotic disease — bacterial systemic infection caused by pathogenic Leptospira — which is highly integrated with an environment in which both humans and animals thrive. The disease, which began to be reported in Kerala since 1989, has been endemic in the State since the last three decades or more and has now become the communicable disease with the highest mortality profile. Leptospirosis is reported throughout the year in Kerala but the cases and mortality begin surging with the arrival of the Southwest monsoon. Since the past three years, the State has been consistently reporting around 5,000 cases and close to 400 deaths (including confirmed and probable) every year. Leptospirosis is yet again in focus now, as the disease has claimed 50 lives just in the month of July this year. What makes Kerala a hotspot for the disease? Kerala’s unique environment, with heavy monsoons, frequent floods and year-round moisture and humidity create ideal survival conditions for Leptospira bacteria in soil and waterbodies such as lakes and canals. An abundance of rodent and animal reservoir hosts live in close proximity to human residential areas and farms. Paddy cultivation, pineapple plantations and canal cleaning activities expose large numbers of agricultural and manual labourers in productive ages to contaminated water, leading the leptospira to enter the body through mucosal surfaces or abrasions or broken skin. The Health Department maintains that according to the data of Centre for Disease Control, leptospirosis is endemic in at least 12 other States, with high burden of disease.
It is better disease surveillance, extensive diagnostic facilities and aggressive logging of both confirmed and probable cases that makes Kerala seem like the State with the highest leptospirosis burden, it is claimed. Which is the population most affected by leptospirosis? Traditionally, leptospirosis has remained an occupational hazard, with people engaged in farming, dairy farming, cleaning workers — essentially, people are at high risk of coming into contact with soil and contaminated water — contracting the disease. The disease typically affects those in the low socio economic strata, but there have also been cases in urban areas, where women have contracted the disease following gardening (possibly bare-handed). Health Department has also identified that construction workers — especially the migrant workers who are employed in the road works on the State’s Highways — are at heightened risk of contracting leptospirosis as they are constantly in touch with soil. The proliferation of wayside eateries has increased the chances of soil contamination by rodents. A data sheet released by the State health authorities just two days ago, showed that in 2025, 36.75% of the deaths owing to leptospirosis had been in manual labourers, followed by agricultural labourers (10.94%) and home makers engaged in gardening (10.16%). What is making the case fatality rate go up? Late diagnosis and rapid progression of the disease, leading to a cascade of lethal complications such as pulmonary haemorrhage and multi-organ failure between 4.5 to 5 days, leaving a narrow therapeutic window for clinicians to intervene, has been making leptospirosis a very unpredictable disease with difficult prognosis in recent times.
The BriefWire