Chikungunya virus may be here to stay: Expert

Scientist working on vaccine says it'll be tough for Singapore to wean itself from virus
Judith Tan, Straits Times 14 Jun 08;

CHIKUNGUNYA surfaced in Singapore in January this year, infecting 13 people in Little India.

Then, two cases of the dengue-like illness emerged in Upper Thomson Road five months later.

And only two days ago, an expatriate housewife in Farrer Road was diagnosed with the disease.

Now, a scientist working on a vaccine against chikungunya believes it is just a matter of time before the virus becomes a permanent part of Singapore's disease landscape.

Dr Lee Smith, vice-president for product development at local biotech firm SingVax, said: 'Singapore is surrounded by Thailand, Malaysia and Indonesia where the disease is endemic. It is difficult for Singapore to wean itself from the chikungunya virus.'

Dr Smith said it was 'quite amazing' that Singapore has avoided large-scale outbreaks of the mosquito-borne disease for so many years.

Like dengue, chikungunya is spread by the Aedes mosquito. Its symptoms, which usually appear within days, include fever, headache, fatigue, nausea, vomiting, muscle ache, rash and joint pain.

These are similar to symptoms of dengue, which makes diagnosing the disease difficult. It can be distinguished only after a laboratory test of the patient's blood.

Dr Smith said that recently, however, the chikungunya virus had gone through a genetic mutation.

It can now be carried by the Aedes albopictus mosquito, cousin to the Aedes aegypti, which is known to spread both chikungunya and dengue.

'The mutation made it easier for the virus to reproduce inside the Aedes albopictus mosquito, more commonly known as the Asian Tiger mosquito because of its stripes. It has been found in Mediterranean Europe and has travelled north to Germany. It was the vector that caused the epidemic in northern Italy last year,' Dr Smith said.

The latest case diagnosed here was a 37-year-old expatriate housewife who lives in the Farrer Road area.

She developed symptoms last week and sought outpatient treatment two days later.

As she and her family did not travel recently, it was likely a case of local transmission.

But a spokesman for the Health Ministry said there is no need for mass screening in the latest case since family members and close neighbours did not catch the virus.

The housewife was discharged from hospital on Thursday.

The disease usually lasts three to 10 days so patients should rest, hydrate regularly and take medication for fever and pain.

There is currently no cure for the disease but last month SingVax announced plans to start work on a vaccine.

Dr Smith said the United States military has already developed a vaccine against the virus but it has yet to see the light of day.

'Priorities have since changed. The focus now is global terrorism,' he said.

The military's vaccine has already been tested on people who have contracted the disease. Dr Smith said local researchers are working with the US military to expand those trials.

Disease common in other parts of the world
Straits Times 14 Jun 08;

WHILE chikungunya fever is rarely fatal, deaths have been reported overseas.

The disease is endemic in places such as India, Africa, Sri Lanka, Malaysia and Indonesia.

It was first reported in Tanzania in 1953.

In India, the disease was first reported in Calcutta in 1963. From March 2005 to March 2006, more than 3,000 cases were found on La Reunion, a French island located on the Indian Ocean.

Since then, other countries in the south-west Indian Ocean have also reported chikungunya cases.

In 2006, several European countries - France, Germany, Italy, Norway and Switzerland - reportedly saw imported cases.

Last year, an outbreak of chikungunya fever was reported in the province of Ravenna in north-eastern Italy. As of last November, a total of 204 cases were confirmed.

The Italian epidemic marked the first outbreak in Europe.

The Pasteur Institute in France found that the virus had mutated and can be transmitted by the Aedes albopictus mosquito. This species is present all over Europe.

Since the beginning of this year, there has been a total of 24 chikungunya cases in Singapore. Out of these, 16 were locally transmitted.

JUDITH TAN

Farrer Road market stallholders concerned about recent chikungunya case
Channel NewsAsia 13 Jun 08;

SINGAPORE: Stallholders in the Farrer Road area are getting concerned after the most recent single case of chikungunya was found in the area.

Stallholders pointed out some potential mosquito breeding sites such as a false ceiling where water sometimes collects.

The recent spate of wet weather hasn't helped improve the situation.

Residents also said there is also a need for authorities to ensure common areas are kept clean.

Two cases of chikungunya fever were detected in the Teachers Housing Estate near the Upper Thomson Road area. It was the first time the disease has been found locally, outside the Little India cluster.

The Ministry of Health (MOH) was informed on 3 June that an 86-year-old retiree had chikungunya fever. She was admitted to hospital but has since been released.

Then on 5 June, a maid from the same household was detected to have the fever too, following a blood screening. She received outpatient treatment.

Investigations revealed that this was likely a case of local transmission as both did not travel recently. - CNA/vm