Heaps of rotting garbage, open drains and drums of stagnant fresh water - the Mayapuri slum in the west of Delhi is full of the very things that a city in the throes of a mosquito-borne outbreak should be desperate to avoid. Not surprisingly, its residents, most of them migrant laborers, are paying a heavy price.

Nearly all the 2,500 tenements located along a railway line have at least one person down with "the fever," as people here call it - a reference to dengue and chikungunya - both viral diseases spread by mosquitoes that bite during daylight hours. Dengue can be fatal if not treated in time; and chikungunya cripples patients with excruciating joint pain.

The latter is what knocked out Golu Kumar Paswan a week ago. The 18-year-old, who works as a laborer in a manufacturing facility, developed a high fever and pain. The virus has sapped him of all energy, making it impossible for him to go to work.

"My company doesn't pay me when I don't show up, so I'm losing out on my wages, which I need desperately to pay for my rent in Delhi and to send back to my family in the Uttar Pradesh state," Paswan said. "Things are really difficult. How am I going to survive?"

Worker crunch hits industrial output

It's a question that many of Paswan's fellow migrant workers laid low by the viral illnesses have answered by packing up their bags and leaving for their villages.

That has left the over 1,500 small-scale factories in Mayapuri, an industrial hub that relies on the steady supply of cheap labor from the neighboring slums. Everything from car parts, textiles to machinery is produced here. The area has witnessed a 20 percent dip in production and profits because workers have been calling in sick or leaving to go back home.

Neeraj Sehgal, who runs a factory manufacturing fire-proof doors for trains, offices and residential buildings, says 15 percent of his 50-strong workforce is down with some form of viral illness. That has meant a failure to deliver orders on time and falling profits. A hi-tech cutting machine that Sehgal invested in a few years ago lies idle because the three workers trained to use it are all sick.

"It's not just my factory, but nearly every facility in Mayapuri is facing a shortage of workers. It has badly affected production," Sehgal said. "Since we are small industries, we don't have back-ups. Besides, it is not easy to find replacements for workers that we spend time training."

Low-cost labor on the frontline

It's a similar story in others sectors too. Though there are no official estimates on what the chikungunya outbreak is costing Delhi's economy, there are reports that the viral illnesses have delayed road works and construction projects in the city with workers staying away.

Many of the migrant laborers live in densely-crowded slums or in makeshift huts under bridges and flyovers. A complete lack of sanitation and hygiene, and at times even a roof over their heads, means they are the first ones to get affected by the mosquito-borne illnesses. Sanitation workers are also on the frontline because of the nature of their work at garbage dumps and drains that are breeding grounds for mosquitoes.

Sanjay Gehlot, president of the Swatantara Mazdoor Vikas Sanyukt Morcha, Delhi's biggest union for sanitation workers, estimates that roughly 7,000 garbage collectors in the city are down with fever and telltale symptoms of dengue and chikungunya.

"It's a tough situation. Many of the workers, especially those who aren't completely bedridden, are still going to work because they cannot afford to lose their wages," Gehlot said. "But, of course, they are not as productive. How can you be when you are sick?"

Delhi government under fire

Delhi is no stranger to mosquito-borne illnesses. But this year's dengue and chikunguya outbreak is particularly severe with nearly 3,000 people reportedly infected according to official figures, though experts say the real number is much higher. Nearly 30 deaths in Delhi have been linked to dengue and chikungunya-related complications.

Health experts blame heavier than usual rainfall this year, coupled with the large number of construction projects in the city, as this can create many stagnant pools of water where mosquitoes can breed.

Hospitals and clinics in the city are overflowing with patients lining up with complaints of fever, chills, headache, pains, rashes, delirium and cough, among other symptoms. The local government has been strongly criticized for what is being seen as a lax attitude to the outbreak. The state health minister was criticized for saying the outbreak was a media creation.

Mukesh Yadav, press spokesman for the South Delhi Municipal Corporation, denies the outbreak is affecting the city's productivity, insisting that the government has a handle on the outbreak.

"We are carrying out door to door campaigns in the city, sending in health workers to check for mosquito breeding and carrying out outdoor fogging (spraying insecticide) drives where necessary," Yadav said.

But back at the slum in Mayapuri, residents say they haven't seen any signs of fogging or a clean up so far. "Forget fogging, even the garbage here doesn't get collected for days. What's the point of keeping my room dry and safe from mosquitoes when I have to step out into this mess everyday?” he said, pointing to the slush and rubbish lining the road leading into the slum.