Last chikungunya spurt in 2006, doctors suggest precautions

The sudden spike in chikungunya cases in several parts of north India, including Delhi, has come nearly ten years after a big outbreak of the mosquito- borne disease across the country.
In 2006, over 13 lakh suspected chikangunya fever cases were reported across the country, according to National Vector Borne Disease Control Programme (NVBDCP).
This year till July 28, 9,990 suspected cases of the disease have been recorded, with Karnataka reporting 7,591 cases.
At the AIIMS laboratories, which get blood samples from Delhi and other parts of the country, 362 samples have tested positive during July to August 20.
"Out of 133 samples sent to our labs, 83 were tested positive in July and this month till August 20, out of 502 samples, 279 tested positive for chikungunya," said Lalit Dar of Department of Microbiology at AIIMS.

Health experts have attributed the rise to a possible "evolution" in the virus that carries this disease and change in weather factors like humidity.

"What we have found out is that suddenly number of chikungunya cases have increased in Delhi as also in several other parts of the country.
"The disease is caused by the same aedes aegypti mosquito which causes dengue but the difference is that dengue virus has four strains while chikungunya has only one," NVBDCP Director, A C Dhariwal said.
Dhariwal and other health experts have acknowledged the sudden spike in chikangunya cases but have appealed to people not to panic.

Chikangunya is a debilitating, though not life- threatening, disease with patients showing symptoms similar to dengue. Typical symptoms include high-grade fever, severe joint pain, muscle pain and headache, joint swelling, or rashes. But it is not as dangerous as dengue in which there is a risk of bleeding due to abrupt fall in platelet count.
"The joint pains last longer compared to dengue cases and especially elderly people find it extremely difficult. Though, people should not worry as it not a life-threatening disease like dengue," Dar said.
Safdarjung Hospital Medical Superintendent A K Rai said over 600 patients came to its fever clinic on Sunday.

"We are getting both dengue and chikungunya cases. And, though we have recorded about 42 chikungunya cases, it is actually a lot more," he said.
In Delhi, however, municipal corporations have only
reported 20 cases of chikungunya till August 20.
The states generally affected by chikungunya are Andhra Pradesh, Karnataka, Maharasthra, Madhya Pradesh, Tamil Nadu, Gujarat and Kerala, according to NVBDCP.
Another reason behind the spike in cases in Delhi and other regions could be "reduction in extrinsic incubation period", NVBDCP Director Dhariwal said.
Extrinsic incubation period refers to the time required for the development of a disease agent in a vector, from the time of uptake of the agent to the time when the vector is infective.

"So, it is possible this period has got reduced and so more cases have suddenly come up," he said.
Regional Adviser, World Health Organisation South East Regional Office (WHO-SEARO) Jamsheed Mohammed says, "Spike in chikungunya cases have occurred not just in Delhi but other parts of the country."
"But, we are doing the needful to combat vector-borne diseases, so we prepare guidelines and also build national capacity to lead a programme," he said.
As per NVBDCP, chikungunya occurs in Africa, India and south east Asia and is primarily found in urban or peri-urban areas.
In India, a major epidemic of chikungunya fever was reported in 1963 (Calcutta), 1965 (Pondicherry and Madras in Tamil Nadu, Rajahmundry, Vishakapatnam and Kakinada in Andhra Pradesh; Sagar in Madhya Pradesh; and Nagpur in Maharashtra) and in 1973 in Barsi in Maharashtra. Thereafter, sporadic cases also continued to be recorded, especially in Maharashtra during 1983 and 2000, it said.

According to NVBDCP, 27,553 clinically-suspected cases of chikunguna were reported last year and 16,049 suspected cases in 2014.