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How prevention is the cure for waterborne diseases

Updated 28 Mar, 2018 11:17am
Photo by AFP
Photo by AFP

Clean drinking water is a necessity as well as a basic human right. Recently, though, it has become more of a privilege for the people living in Pakistan. Community health studies reports state that around 50 per cent of diseases and 40 per cent of deaths occur due to poor drinking water quality. United Nations’ subsidiary organisations have reported approximately 1.1 billion people to be deprived of sufficient access to water. The ones with access often have sanitation water and the sewage pipeline running side by side, increasing the chance of a pipe leakage that leads to intermixing. Despite the water standards being similar to those of WHO guidelines, proper adherence and local attention to detail is often skirted.

A four-year report by the Pakistan Council of Research in Water Resources states that 86 per cent of the 28 samples tested in the report in Karachi were contaminated. While the sample size can be questioned, any source of water being polluted can be fatal. Samples collected from Islamabad were 68 per cent adulterated and Lahore had 25 per cent of the tested samples polluted by bacterial contaminants. Overall, 25 cities were tested with around 2,500 samples tested altogether, showing Khyber Pakhtunkhwa’s water quality to be relatively better than other provinces, with 47 per cent samples marked unsafe compared to 81 per cent in Balochistan and Sindh, and 65 per cent in Punjab.

The nature of the detected contaminants in the report ranged from bacterial to arsenic components. In 2015, 81 percent of the samples were deemed contaminated due to bacterial presence. The main reason for microbial contamination is intermixing of sewer lines with drinking water supply lines resulted by pit latrines in many intercity villages. In most rural areas of Pakistan, ground surface water and tube wells are used for drinking without slow sand filtration and chlorination at filtration stations. No pre-treatment facilities are available for filtration of water. Hand pumps and wells are not protected from surface run-off, making the water from such sources not potable.

“Good hygienic care and consistent socio-economic backup support is required from the councils to ameliorate the disease burden as treatment lays in prevention.”

Drinking water should not have colour, turbidity, odour and microbes. Since most of the cities of Pakistan consume ground water as the primary source of drinking water, its infestation with various pathogens such as viral, bacterial and protozoan agents cause 2.5 million deaths from endemic diarrheal disease each year. Waterborne diseases have multiple routes of transmission that include consumption and contact of water, as well as inhalation of mist or aerosolised water particles.

Dr Muhammad Ali Taj, a senior gastroenterologist, states that one of two pathogens cause waterborne diseases. One of them is bacterial that results in gastrointestinal problems like diarrhoea and cholera that may show late symptoms; the other is Acute Viral Hepatitis (AVH) that has similar symptoms as hepatitis A. “Direct consumption of water is not the only way one can get ill; dirty water used to wash vegetables can often lead to waterborne diseases directly as well,” says Dr Taj. “Good hygienic care and consistent socio-economic backup support is required from the councils to ameliorate the disease burden as treatment lays in prevention.”

According to Dr Taj, a higher number of people are seen with acute viral hepatitis as it needs immediate tending to than chronic diseases like diarrhea. AVH is caused due to the transmission of viruses through the fecal-oral route. Often, the hub for pathogens like virus and bacteria reside in the cattle, goats, sheep and seafood we consume. Humans can also be a reservoir. Direct discharged waste from mammals and birds near agricultural sites and storm run-offs can come in contact with nearby waters and drainage and can lead to the contamination of food and water. With a regression in water quality and without active participation from the authorities, prevention is the primary way to avoid waterborne diseases. Prevention strategies can include source protection, halogenation of water, or boiling water for one minute.

In 2016, an outbreak of a drug resistant strain of Typhoid alerted people from consuming food and water products of questionable nature. This strain has mutated and developed an additional piece of DNA that is resistant to multiple antibiotics, which leaves health care professionals with even less treatment options. Therefore, to avoid contracting and spreading such infections, safe consumption of water and food is extremely essential.


The writer is a researcher at Indus Hospital with a degree in Molecular Medicine from Imperial College London and biomedical research experience from University of Cambridge.