Incessant rains lashing Chennai for several days now have submerged the city, with vehicles floating and people using boats to wade through the water logged streets. But as the rains subside and the water recedes, it would be wrong for us to think that life can get back to normalcy easily.
There are rising concerns over a possible outbreak of diseases.
Public health experts say that one of the major causes of concern at present is the contamination of water with sewage, especially drinking water, which can give rise to a host of water-borne diseases like cholera and diarrhoea.
Their advice to people is to boil water that will be used for drinking and cooking.
Dr V Ramasubramanian, a senior consultant in Infectious Diseases, Apollo Hospitals, Chennai, says that water logging can provide for a breeding ground for mosquitoes.
"A rise in cases of malaria, dengue and chikungunya can be expected," he says. Contamination of water can also result in a host of associated diseases like skin diseases, he adds.
"The extent of outbreak of diseases also depends on how fast the corporation can get rid of logged water," he says.
Dr Elango, Former Director of Public Health and Preventive Medicines, Govt of Tamil Nadu, says getting in contact with contaminated water can lead to Leptospirosis.
"Leptospirosis is an epidemic-prone zoonotic bacterial disease that can be transmitted by direct contact with contaminated water. Rodents shed large amounts of leptospires in their urine, and transmission occurs through contact of the skin and mucous membranes with water, damp soil or vegetation (such as sugar cane), or mud contaminated with rodent urine."- CDC
Without proper treatment, Leptospirosis can cause kidney damage, meningitis, liver failure, respiratory distress, and can also prove to be fatal.
Leptospires penetrates through the skin in a screw-like movement, says Dr Elango explains. Some of the precautions that people can take are applying neem or castor oil on their legs and feet, Dr Elango says.
"Corporations can make a mix of 1kg of bleaching powder, 10 kg of sea salt and 10 kg of slaked lime and spread it in areas which have water-logging or even where the water has been drained. This is a low cost technique and will kill the Leptospira bacteria. This mix can also be used in households in a smaller ratio," Dr Elango says.
The common precautions that Dr Elango suggests are boiling water before drinking- at least 1 litre a day per person- and also before cooking, consuming uncontaminated food, using sanitary toilets and using mosquito nets while sleeping.
Contrary to common perceptions, the risk of outbreaks following natural disasters may not always be high, a paper by the Centre for Disease Control and Prevention states.
"The risk for outbreaks after natural disasters is low, particularly when the disaster does not result in substantial population displacement. Communicable diseases are common in displaced populations that have poor access to basic needs such as safe water and sanitation, adequate shelter, and primary healthcare services... Disaster-related deaths are overwhelmingly caused by the initial traumatic impact of the event," the paper reads.
It further adds, "The risk for communicable disease transmission after disasters is associated primarily with the size and characteristics of the population displaced, specifically the proximity of safe water and functioning latrines, the nutritional status of the displaced population, the level of immunity to vaccine-preventable diseases such as measles, and the access to healthcare services.