12 November 2008

Global chikungunya virus activity update

This update reports on a number of current and recent chikungunya virus (CHIKV) outbreaks. It is not a comprehensive listing of all outbreaks. Further information on reported and suspected outbreaks can be accessed via the NaTHNaC Outbreak Surveillance Database.

India

As of 3 November 2008, the Indian government reported 79,000 suspected cases of CHIKV from 12 states of India. No deaths have been reported [1]. The most affected state is Karnataka with 46,087 suspected cases, followed by Kerala (24,652 cases), West Bengal (7,538 cases), Maharashtra (445 cases), and Gujurat (182 cases). The states of Andhra Pradesh, Tamil Nadu, Goa, Haryana, Rajasthan, Delhi and Uttar Pradesh have reported less than 100 cases each.

Indonesia

Media sources have reported outbreaks of CHIKV in Indonesia throughout 2008. Affected areas include the islands of Bali, Java (including Jakarta), Sulawesi, and Sumatra. Details of these unverified outbreaks can be found on the NaTHNaC Outbreak Surveillance Database.

Malaysia

Between 1 January and 1 November 2008, a total of 3,129 cases of CHIKV have been reported [2]. The state of Johor has reported the most cases (1,632). Cases have been reported throughout peninsular Malaysia and in Sarawak on the island of Borneo. Identification and removal of mosquito breeding sites and insecticide spraying of affected areas is ongoing.

             

Maldives

Between 1 January and 4 October 2008, 606 cases of CHIKV were reported [3]. In July 2008, there was a peak in the number of cases (60 cases per week), and since then disease activity has subsided with around 10 cases per week reported throughout September.

Singapore

Since January 2008, Singapore has experienced local as well as imported cases of CHIKV. As of 24 September 2008, a total of 231 cases have been reported. Of these, 108 were imported (99 from Malaysia, four from Indonesia, two from Sri Lanka, two from India and one from the Maldives). The remaining 123 cases were acquired locally [4]. Vector control measures have been implemented.

Thailand

Between 1 August and 7 October 2008, 82 cases of CHIKV were reported in a village in Narathiwat province [5]. Laboratory testing of samples from 38 of the cases showed evidence of infection with CHIKV. The peak of the outbreak was mid-September, and the number of new cases is now declining.

Advice for Travellers

Chikungunya virus is a mosquito transmitted viral infection and is endemic to large parts of Africa, the Middle East, India and South East Asia.

Initial symptoms include sudden onset of severe arthralgias and myalgias, accompanied by fever, headache and conjunctivitis. Joint involvement is usually symmetrical, affects the extremities and can result in swelling, pain, redness and limitation of movement.

A maculopapular rash involving primarily the trunk can occur concurrently with resolution of fever. Ilness usually resolves over three to five days. Most patients recover fully over a period of a few weeks, although 5 - 10% of patients will experience persistent joint pain, stiffness and swelling.

There is no vaccine available to protect against CHIKV. Travellers to affected areas are advised to take insect bite precautions, particularly during daylight hours when Aedes mosquitoes are active.

Health professionals in the UK should consider the diagnosis of CHIKV infection in returned travellers with a compatible illness and travel history.

References

1. Indian Government Directorate of National Vector Borne Disease Control Programme. Status report on Dengue and Chikungunya as on 03.11.08. [Accessed 11 November 2008]. Available at: http://www.nvbdcp.gov.in/Doc/dengue-chikun-report-03.11.08.pdf  

2. Ministry of Health of Malaysia. Current situation of chikungunya infection in Malaysia, 1 November 2008 (In Malay). [Accessed 11 November 2008]. Available at: http://www.moh.gov.my/MohPortal/newsFull.jsp?action=load&id

=367  

3. Ministry of Health of the Maldives. Fortnightly epidemiological report, wk 39 & 40 2008, 2 November 2008. [Accessed 11 November 2008]. Available at: http://www.health.gov.mv/publications.asp?id=5&PagePos=4

4. Ministry of Health of Singapore. Update on chikungunya fever situation (5), 25 September 2008. [Accessed 11 November 2008]. Available at: http://www.moh.gov.sg/mohcorp/pressreleases.aspx?id=20014

5. World Health Organization Regional Office for South East Asia. Communicable disease newsletter, October 2008. [Accessed 11 November 2008]. Available at: http://www.searo.who.int/LinkFiles/CDS_News_letter_vol-5_issue-3.pdf

Links

Health Protection Agency. Chikungunya.

United States Centre for Disease Control and Prevention. Chikungunya Fact Sheet

European Centre for Disease Prevention and Control: Chikungunya fever