Waded through Mumbai rainwater? BMC issues leptospirosis advisory — Symptoms, crucial 72-hour window & more

After days of incessant monsoon showers, Mumbai witnessed a generally cloudy day with little to no rain in most parts on Thursday. This provided relief after a prolonged wet spell that had caused waterlogging, tree falls, traffic snarls and disruption to suburban rail services.

Commuters wading through heavily waterlogged streets in areas like Vasai, Virar, and other Mumbai suburbs have been a common sight since the monsoon first hit the city. And the BMC has issued an urgent health advisory urging residents to take preventive measures against leptospirosis, a potentially fatal infection.

Avoid walking in stagnant rainwater: BMC

The Brihanmumbai Municipal Corporation (BMC) has advised citizens to take precautions against leptospirosis, a bacterial disease commonly spread through contaminated floodwater.

"Stagnant rainwater can harbour diseases like leptospirosis. Avoid walking in Stagnant rainwater!

What is Leptospirosis?

Unlike mosquito-borne seasonal illnesses such as dengue or malaria, leptospirosis is a bacterial infection caused by the Leptospira bacteria. The disease is zoonotic, meaning it spreads from animals to humans.

During the monsoon, the urine of infected animals—predominantly rats, but also stray dogs, horses, and livestock—washes into puddles, potholes, and flooded streets. When a person wades through contaminated, stagnant water, Leptospira bacteria can easily enter the human body.

They do not need a massive open wound to invade; the bacteria can slip through minor cuts, microscopic skin abrasions, or even the mucous membranes of the eyes, nose, and mouth.

Leptospirosis: Symptoms

One of the greatest dangers of leptospirosis is how easily it masquerades as a common viral fever in its early stages. The incubation period ranges from two days to four weeks, after which the infected individual may experience:

• High fever and sudden chills
• Severe muscle pain, particularly in the calves and lower back
• Intense headaches
• Red or bloodshot eyes
• Nausea, vomiting, and diarrhoea
• Jaundice or skin rashes

Because these initial symptoms are so generic, many people dismiss them or attempt self-medication. However, if leptospirosis is left untreated, it can rapidly progress to severe complications.

In its advanced stages, it can cause Weil's disease, leading to acute kidney damage, liver failure, respiratory distress, internal bleeding, meningitis, and even death.

72-hour golden window and BMC protocol

To prevent the infection from taking root, the BMC’s advisory emphasised one critical directive: the 72-hour golden window.

Any Mumbaikar who has waded through floodwater is advised to seek medical advice and begin prophylactic (preventive) treatment within 24 to 72 hours of exposure.

The BMC categorised exposure into distinct risk levels to guide treatment:

• Low Risk: Individuals who walked through floodwater once and have no visible cuts or wounds.
• Moderate Risk: Individuals who waded through water and have minor injuries, cuts, or abrasions on their feet or legs.
• High Risk: People exposed to stagnant water multiple times or professionals (like sanitation and rescue workers) with prolonged contact.

Typically, antibiotics such as Doxycycline or Azithromycin are used to treat the infection. Doctors prescribe them tailored to the individual's risk level and age.

Receiving treatment within the first 72 hours effectively neutralises the bacteria before they can multiply and attack vital organs.

Commuters wading through the waterlogged streets are advised to wash exposed skin with soap thoroughly, recognise early symptoms, and strictly adhere to the 72-hour golden window to protect themselves this monsoon.

IMD forecast

The India Meteorological Department (IMD) has forecast a generally cloudy sky with intermittent light to moderate rainfall in the city and suburbs during the day.

Heavy rainfall is likely at isolated places, accompanied by lightning, thunder and occasional gusty winds reaching speeds of 40-50 kmph, the BMC said.

The island city received an average rainfall of 14.21 mm in the 24 hours ending at 8 am on Thursday, while the eastern suburbs recorded 39.37 mm and the western suburbs 28.85 mm, according to BMC.