CHIKUNGUNYA

Lohith Reddy

• First outbreak of the disease

• in the year 1952

• in the Makonde plateau, along the border between Tanzania and Mozambique.

• Chikungunya is a Makonde word (one of the local languages in Tanzania) meaning

‘that which bends up’.

• Describes the posture patient assumes to relieve the severe joint pains

• The disease was first described

Marion Robinson

and

W.H.R. Lumsden in 1955

An Epidemic of Virus Disease in Southern Province, Tanganyika Territory, in 1952-53;II. General Description and Epidemiology," in the Transactions of the Royal Society of Tropical Medicine and Hygiene, Volume 49, Number 1, January 1955.

The Indian Scenario

• First outbreak

India

1963

Calcutta

• Since the first reported case in 1963 there have been sporadic outbreaks in varies parts of India.

• Re-emergence of the disease in India

especially in the southern states.

• Outbreak in December 2005 more that 3,80,000 reported cases of Chikungunya in India.

Closer to home

• State of Karnataka reported 78,000 cases

• Andhra Pradesh reported 200,000 cases.

The First Culprit

• Chikungunya Virus,

or• Buggy Creek Virus

• Family -Togaviridae

• Genus - Alpha virus.

• enveloped virions • spherical, 60 to 70 nm

in diameter • positive-sense,

single-stranded RNA genome, ca.

• 11.7 kilobases long.

• Lipid-containing envelope has two (rarely three) surface glycoproteins.

• Mediates attachment, fusion, and penetration.

• French researchers on the Indian Ocean island of Reunion say

re-emergence was spurred by a mutated form.

• Two changes to the structure of E1

• Makes the virus more likely to enter mosquito cells and replicate after the insect has fed on the blood of an infected person.

Second culprit

• Aedes aegypti (the yellow fever mosquito),

• Aedes albopictus (the Asian tiger mosquito)