A line of men in black rain boots push trash carts through the alleys of Lahore, Pakistan. They stop at an open sewer along a neighborhood street and start to pull up shoes, bricks, plates and any other trash that might block the flow of wastewater.
Standing water is a prime breeding ground for mosquitoes. And the local government in Lahore is on a focused mission: Stop the spread of dengue fever by mosquitoes.
Two years ago, an estimated 20,000 people in and around the city of Lahore contracted the deadly tropical disease. This year, the region has recorded just a few dozen cases of dengue fever, which usually involves a high fever, horrible headache, and severe bone and joint pain.
What triggered the sharp decline in dengue cases? Fortuitous weather patterns may have helped to keep the mosquito population low. But many leaders also credit a mobile phone app — and the public health campaign that uses it.
"We pull up the trash, put it in the basket, tie up the bag and take it away," says sanitation worker Tanvir Channa. He says that he doesn’t often think about his role in combating a deadly epidemic. "Whatever I do, it’s just to provide for my kids," the thin 30-year-old says.
To make sure workers like Channa don’t skip out on their tasks and allow the dengue mosquitoes to breed, they’re followed by an investigator who uses a smartphone to their progress. In this case, it’s a tall man in plaid shirt named Mohammad Saleem Taqi.
"I open this application, called Clean Lahore, to enter a field activity," he says. "I take pictures before and after the work is done, enable location services to map this spot, and then send it on to my supervisors."
In the photograph, an inspector Mohammad Saleem Taqi takes a snapshot of sanitation workers as they clear out debris in sewers. The government feeds the photos into a map to track the city’s effort to stop dengue fever. (Beenish Ahmed/NPR)