Hilly hamlets of Kasargod, Kerala's [Images] northern district, are in the grip of an unprecedented viral fever which has affected around 2,000 people who have symptoms akin to chikungunya, causing concern among health officials.

The situation has aggravated with the onset of the monsoon, leading to heavy breeding ground for mosquitoes, which transmit the chikungunya virus that hit the districts of Kottayam, Pathanamthitta and Alappuzha last year on the large scale.

Hundreds of people, mostly from middle and lower income groups, have been afflicted with viral fever with complaints of acute joint pain and rashes on their bodies and long queues outside government and private hospitals have become a daily feature.

While majority of the viral fever cases reported in the affected hilly locality is endemic in nature, officials have expressed concern over mounting cases with chikungunya symptoms with the aedes albopictus mosquitoes getting an easy breeding ground in water-logged areas and rubber farms, deputy district medical Officer Dr M Kunhiraman said.

The maximum number of cases were reported from Panathady, Kallar, Balal, Kuttikol, Muliyar and Kumbadaje villages that lie closer to adjoining Karnataka where chikungunya cases had been reported during April which saw heavy unseasonal rains, sources here said.

Officials so far confirmed 11 chikungunya cases while fresh cases with the symptoms were being reported every day.

Most affected people are engaged in rubber and areca farms. Besides prescribing medicines, the doctors advise patients to take at least a week-long rest to reduce the severity of the disease besides suggesting precautionary measures.

The fever spreads quickly as the Aedes mosquitoes can intake up to 0.5 micro litre blood and target another person.

"The rain water collected in shells used for collecting rubber milk and the sprinkled irrigated water accumulated in areca palms becomes easy breeding ground for the mosquitoes and those bitten by such mosquitoes automatically fall victim to the painful disease," district malaria officer V Suresh said.