"I've never seen such a fierce presence of flies in my life," says a 45-year-old resident.
Swarms of flies are descending on Karachi in what residents say are record numbers in this rainy season, which adds to the misery of the "hell" of the city monsoon.
Heavy rains have flooded the port city of nearly 20 million people for weeks, overwhelming poor quality drainage systems clogged with mountains of uncollected garbage and flooding neighborhoods with sewage.
"I have never seen such a fierce presence of flies in my life," said Abdul Aziz, 45, a Karachi resident. AFP.
“Clouds of flies continue to cover food in the market. It's repulsive: they cover the fruit so much that it can't be seen under them. "
At a market in the city of Surjani, meat trader Zahid Ali watched the flies wrap around the area.
"If customers come, they leave impulsively after seeing swarms of flies," Ali said, adding that an increasing number of people working in the market became ill.
Shershah Syed, a health rights activist and prominent surgeon in Karachi, said many diseases were on the rise due to flies and mosquitoes.
"This time (the flies) are the worst, since the rainwater cannot be drained and the piles of garbage are not handled," Syed said.
“The number of children entering hospitals due to diarrhea or dysentery has multiplied by several this year. The number of children, who are the most vulnerable to fly-borne diseases, has increased by approximately 10 times. "
While Karachi is responsible for 60 percent of Pakistan's economic production, the city has long suffered a squeaky infrastructure, illegal construction and failed municipal services.
This week, The Economist Intelligence Unit ranked Karachi as one of the least livable cities in the world, along with Tripoli, Libya, devastated by war, and Caracas, the Venezuelan capital affected by the crisis.
"People in Karachi are insensitive to the idea of living with medical waste, gutter overflows, broken roads and the total lack of any respectable public transportation system," Saadat Ali Zia wrote on Twitter.
"We live in hell," Farooq Afridi tweeted.