A cholera outbreak seems to have returned to the city and is being transmitted by the Wasa water supply system.

So far, the worst affected area is Dakshinkhan, with Jatrabari trailing right behind. Other top areas include Mohammadpur, Sabujbagh and Mirpur.

"In my 36-year-long career, I have never seen so many diarrhoea patients," said Dr Tahmeed Ahmed, executive director of International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b).

"I would call this an outbreak."

The 350-bed hospital has been seeing three times more inpatients coming in daily, while tents strung up on the premises are having to house the rest -- a vast majority of whom should be able to go home within 24 hours.

"About 23 percent of all the diarrhoea patients coming in were found to be infected with the bacteria called vibrio cholerae," said Dr Md Nazmul Islam, line director of Communicable Disease Control department of the Directorate General of Health Services, citing figures from March 8 to 15.

Exhausted after losing a lot of fluid, five-year-old Fatema falls asleep in a bed at the icddr,b where she was admitted yesterday. The hospital in the capital’s Mohakhali has been dealing with a high number of diarrhoea patients over the past few days. Photo: Rashed Shumon

Nearly half of the patients' pathogens could not be identified and at least half of the other half, whose pathogens could be identified, have cholera.

Dr Ahmed points out that summer-time diarrhoea and cholera flare-ups are normal, but this time, it is the scale that made the difference.

On March 26, approximately 1,200 patients visited the hospital, while around the same time last year, there were 600.

In March 2021, it saw a staggering 750 patients in one day.

However, this year the hospital has been logging over a thousand patient visits every single day since March 13.

In Jatrabari's Shuti Khalpar, locals say every other house has diarrhoea. Nearly 30 percent of all patients who visited the emergency ward of the Islamia General Hospital on Dhalpur Road were suffering from diarrhoea, intake records show.

Shuti Khalpar is an area where vehicles are a rare sight, but pedestrians throng the broken tarmac. Hawkers with baskets sit smack-dab in the middle of the road, despite it being a major street.

Anybody in the locality, who can afford a Tk 30 five-gallon water canister, purchases their drinking water here.

As a severely dehydrated Sohel Rana was hooked to an IV saline, listless in bed, his colleague wondered what caused this.

"We are bachelors sharing a flat. We work as collectors for a microfinance NGO. We buy our drinking water, but we use supply water for washing and [sometimes for] drinking," said Rana's colleague.

Nazma Begum, a resident in Shuti Khalpar, held up a glass of supply water with greenish-brown tinge. It smelled mildly of urine, suggesting cross-contamination with sewage lines.

In 2019, Jatrabari's water sample was tested by the local government and rural development (LGRD) ministry. The tests found both coliform and heterotrophic bacteria -- vibrio cholerae is a type of the latter.

Based on their reports, the High Court had demanded an explanation from the Dhaka Water Supply and Sewerage Authority.

Dr Ahmed said the water is perfectly safe at the source but gets contaminated when being supplied through the network.

Abdul Khaleque, operator of Dakshinkhan's Mollapara water pump, explained how the supply water gets contaminated: "A new pipeline has been introduced a week ago. We have to stop supplying water to the old one when we supply to the new. As a result, sewage water seeps into the pipelines because of negative pressure."

Taslima, a 40-year-old homemaker, gets the supply water in her house. She had just returned home following her treatment at icddr,b a few hours before the filing of this report.

Her block in Mollapara houses 15 families living in adjacent rooms in a row. It had six diarrhoea patients.

"I used to drink boiled water, but I still got sick. The toilet water often gets mixed with the supply water," she said.

Md Muzahidur Rahman, executive engineer of Zone 9, which includes Dakshinkhan, said, "The problem will be solved once the [pipeline] work is finished. We have been notified by the icddr,b about the outbreak. The situation may improve within a week."

Meanwhile, in Jatrabari's Gobindapur area, the breaches in supply lines are directly caused by the residents.

Hosepipes flow out directly from the side of the Gobindapur water pump and run across the roadand to residences. They are stomped on by pedestrians and run over by rickshaws. Resultant holes are temporarily fixed with only duct tape.

Pradeep Kanti Das, a resident in the area, said, "We had to resort to this [hosepipe] because our water comes from another pump from across the highway. As so many heavy vehicles ply the road, we get no water [from there]. All the homes get their water through hosepipes."

Pump operator Shipon Miah, standing next to Pradeep while he talked, feigned ignorance about the pipes.

"All our pipes run five feet underground. They are illegal. I know nothing about this… I came here three months ago," he said.

Pradeep countered, "Wasa officials know about this. None of this is free water. We pay monthly bills for it."

Al Amin, Wasa's executive engineer in Zone-1, said, "We have heard about a diarrhoea outbreak from icddr,b and have ramped up monitoring. We have checked our systems and found nothing wrong.

"We have still asked the chlorination department to be vigilant. There is a lot of water demand during the summer; so if there are leaks in the pipe, negative pressure causes sewage to seep in. Furthermore, water reservoirs are often unclean."