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Poonam Devi moans in pain on the stretcher in the packed hospital emergency room, her ankles and wrists swollen, an IV hooked up to left arm to hydrate her.

Patients like her, fevered, aching, unable to walk or sit on their own, are packing hospitals across New Delhi because of chikungunya, a mosquito-borne viral illness. In the Indian capital alone, cases of chikungunya soared to 3,251 so far this year from just 64 last year, according to government data. Last year it was dengue, another viral ailment transmitted by mosquitoes, that infected thousands.

The cycle of illness and packed hospital "fever clinics" plays out every year as monsoon rains fill puddles and open drains in the teeming city, creating swarms of mosquitoes that thrive in the warm, damp weather.

Some years it's mainly dengue; in others, it's mostly chikungunya. The epidemics start promptly in August and stay for months, sickening tens of thousands and killing dozens, each year seeming to catch the government and population unprepared for it.

"Everyone in our neighborhood is getting it," said Devi's sister, Susheela, who goes by one name. She sat holding her sister's hand inside Ram Manohar Lohia Hospital, one of the city's largest government-run hospitals. A portion of the hospital's emergency room has been set aside for chikungunya patients like Devi.

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One day last week, Dr. Prerna Mor, who was supervising incoming patients at the hospital, had already seen nearly 300 patients with clinical symptoms of chikungunya in the first four hours of her shift. Mor, a fellow resident and a few nurses quickly assessed patients before other doctors took over.

Dengue and chikungunya have killed at least 20 people in the capital so far this year, according to news reports. But statistics on the illnesses are likely conservative since the poorest people in this city of 16 million never see a doctor or a hospital. Both diseases are treated only for their symptoms, reducing the fever and relieving the aches, until the infection passes. As a result, tens of thousands of people are tested at private laboratories and treated at private clinics, which don't report on what made their patients sick unless the government specifically asks.

Just as predictable as the illnesses each year is the shifting of blame as soon as the public hears of the soaring number of cases. Each year the government goes into overdrive only after hundreds if not thousands have already been sickened.

This year is no different.

Stung by criticism that it has handled the outbreak so far very poorly, the local government has set up hundreds of clinics, like the one where Devi was diagnosed, to treat chikungunya, dengue and malaria patients. It has canceled all vacation for doctors and staff at government-run clinics and hospitals.

Hundreds of municipal workers rushed to trim knee-high grass in public parks and fog the city with anti-mosquito pesticides — after many had already gotten sick.

But experts say responsibility for controlling diseases spread by mosquitoes cannot be the government's alone. Officials conduct public-awareness advertising campaigns urging people to wear long sleeves, use mosquito repellent and get rid of standing water. But the advice is routinely ignored, even with municipal workers going from home to home in some neighborhoods on the lookout for mosquito breeding areas.

"There's no community participation here. People want the government to take the entire responsibility of keeping their neighborhoods clean," said Dr. A.K. Gadpayle, medical superintendent at Ram Manohar Lohia Hospital.

Without the communities coming together to ensure mosquitoes don't breed, "no government anywhere in the world can succeed," he added.

The annual outbreak comes as health experts and governments contemplate the potential for a global outbreak of another mosquito-borne illness, Zika. Like dengue and chikungunya, Zika is transmitted by the Aedes aegypti and Aedes albopictus mosquitoes.

A recent study published in medical journal Lancet says 2.6 billion people living in parts of Asia and Africa could be at risk of Zika infection, based on analysis of travel, climate and mosquito patterns in those regions.

But experts in India caution that the study may exaggerate the risks because the Zika virus has been around since the late 1940s and it's not clear if the virus had reached these countries sometime in the past, allowing people to build immunity.

Zika can cause fetal death and severe brain defects in the children of women infected during pregnancy. Yet the vast majority of people infected never get sick, and symptoms are mild for those who do, so surveillance systems may have missed cases.

No cases of Zika have been reported in India so far.

"In the times of rapid international travel, and international mass gatherings such as the FIFA World Cup and the Olympics, or religious gatherings like the hajj, there is always a potential threat of import of Zika infection," said Dr. Lalit Pant, an infectious diseases specialist at the Public Health Foundation of India.

But the country has facilities to test people for Zika if cases are reported, Pant added. "We know what to do. The challenge is how well can we do."

At Ram Manohar Lohia Hospital, Gadpayle isn't too concerned about Zika. He has his hands full with chikungunya this year.