One morning in the last week of December in 2015, Radha Singh*, a pathologist in Pune, woke up and found she was unable to move. “I was completely frozen," she said. "I wasn’t able to get up from my chair even with help.”

The 61-year-old doctor was diagnosed with chikungunya, a viral disease transmitted to humans by infected mosquitoes. It leads to high fever and severe joint pain. While the fever abates within a few days, the joint pain often lasts longer, stretching upto a few months, particularly among older patients.

In Singh's case, the infection left her bedridden for six months. “In my career of 30 years, it was the first time I took medical leave,” said the doctor who resumed work just a fortnight ago. “I still can’t drive as it is painful to bend my leg joints.”

An ignored disease

Chikungunya rarely kills but the symptoms can be severe and debilitating. “The morbidity as a result of the disease is just one step lesser than mortality,” said Singh.

Despite this, government health departments in India tend to ignore chikungunya.

Like dengue, the chikungunya virus is transmitted through the Aedes Aegypti mosquito, but government awareness campaigns are focused on dengue. The infection is often underreported.

Take for instance, Delhi, which is currently witnessing a surge in chikungunya cases. Officially, Delhi government's health department has declared 50 cases of chikungunya, the Indian Express reported on Wednesday. But the director of the National Vector Borne Disease Control Program, Dr AC Dhariwal, told that 300 patients in Delhi have tested positive for chikungunya.

Even this number could be an underestimate, said doctors. Several of them claimed they were treating an average of three to four cases a day.

Dr Suranjeet Chatterjee, a senior consultant at the Indraprastha Apollo Hospitals, said he had treated about 25 cases of chikungunya over the last week. “Most of them had high grade fever with severe joint pains,” he said.

An official at a popular diagnostic laboratory in Delhi said that they receive at least 25 to 30 samples every day for chikungunya testing. Refusing the share the absolute numbers, he said that about 60% of the samples tested positive. In comparison, the positivity for dengue was between 10% to 20%, he added.

Unlike dengue, doctors rarely prescribed a chikungunya test. “It doesn’t matter if the test is positive as the treatment remains the same,” explained a senior doctor from a hospital in Mumbai. “Why spend money on testing, when we can use that money towards treatment."

This further contributes to the undercounting of the disease.

What leads to an epidemic

In a press statement on Wednesday, the Union health ministry attributed the rise in cases in Delhi to its "non-immune population". When the population of a city is exposed to a particular virus, it develops immunity against it. In medical terms, this is called “herd immunity”. Owing to the immunity, the likelihood of people contracting the infection is slightly lesser as the body already knows how to fight it.

In the case of Delhi, its people were more susceptible to chikungunya since the virus had not been in wide circulation in the city previously, unlike the states of Karnataka and Maharashtra, which have seen major outbreaks.

In 2006, India had witnessed an epidemic of chikungunya with 12.5 lakh suspected cases of reported from different states, according to the World Health Organisation. The highest burden was found in Karnataka and Maharashtra.

A heavy toll

A study published in the Journal of Rheumatology found that 16.2% of chikungunya cases reported in Kozhikode district in Kerala in 2009 developed some form of disability. “They had difficulty in bending, walking and climbing stairs,” said Dr Asma Rahim, the author of the paper and additional professor at the Department of Community Medicine in Government Medical College, Kozhikode. Many patients complained of pain for as long as 18 months after they contracted the infection, Rahim added.

This leads to a loss of productivity and income.

A study conducted by Vector Control Research Centre in Puducherry estimated that the 2006 outbreak led to losses amounting Rs 39.1 crores. The real losses could be higher as the calculation was made on the basis of the minimum wage set by the government, and not real wages.

The study also found that patients took an average of nine days in the case of acute illness and six months in the case of chronic illness to recuperate from the symptoms.

Like dengue, there is no cure for chikungunya in the form of a drug that can attack the virus. Doctors administer treatment to control the symptoms, as the body’s own immunity fights the disease.

This adds to the ordeal for patients. Singh was on steroid for almost five months to manage her symptoms. “Three of the medicines that I took gave me severe allergy which only worsened my condition,” she recalled.

Not all patients, however, face debilitating symptoms. Said a doctor in Pune: “In just 0.5% cases, the pain and swelling will continue for over six months.”

*The name has been changed on request.