Singapore: Six workers become first to get chikungunya disease

Lee Hui Chieh, Straits Times 18 Jan 08;

SIX people have become the first to catch a mosquito-borne, dengue-like illness here.

Concerned that the disease, chikungunya, could take root here like dengue, health and environment officials have swung into action to ensure it does not do so. They are checking everyone who lives or works within a 150m radius of the six cases.

Chikungunya first appeared here in 2006, but all cases since then - including the 10 last year - were imported ones. The six victims in this outbreak are all foreign nationals in their 20s and 30s from Bangladesh and India.

Four have already recovered; the rest were admitted to the Communicable Disease Centre (CDC) on Wednesday.

Like the dengue virus, the chikungunya virus is spread by the Aedes mosquito. A bite from a mosquito infected with the chikungunya virus brings on symptoms similar to dengue, such as fever, joint pains, chills and nausea, which last up to 10 days, though the joint pains may last weeks or even months. No treatment is available. The disease usually runs its course and goes away on its own.

Though rarely fatal, it has claimed lives in India and Reunion Island in recent years.

The death toll shows that chikungunya is not something that can be dismissed, said the CDC's clinical director, Associate Professor Leo Yee Sin.

The Health Ministry is still investigating how the outbreak here began. It was notified on Monday by a general practitioner that one of his patients, a 27-year-old Bangladeshi man, had tested positive for the chikungunya virus.

The man, ill since last Wednesday, had gone to the doctor the next day. He has not left Singapore since arriving here in 2005, and with the one-week incubation period of the virus, health officials realised he probably contracted it here.

They fanned out to screen and collect blood samples from people in Clive Street, next to Tekka Mall in Serangoon, where the man lives.

Five others, who have also not been out of the country in the past month, were found to have been infected and were taken to the CDC for checks.

One of them, Mr Vidwasekar Gnanasigamani, 38, a farmer from India, said in Tamil: 'On the first day, the pain was so bad that I couldn't walk. Now I'm better, but I still have a fever.'

Conditions here - the presence of the Aedes mosquito, and a population with no immunity to this disease - are ripe for chikungunya to become endemic, said Prof Leo.

The information at the moment shows the outbreak to be localised, said Dr Lyn James, director of the Health Ministry's communicable diseases division. But the ministry is going all out to track down all infected individuals 'to prevent the disease from taking a foothold in Singapore', she said.

From the immediate area around Clive Street, it has expanded screening to an area within a 150m radius of the street.

Almost 500 people have been screened in the last two days. Those found with the virus have been isolated in the CDC to prevent them from being bitten again by mosquitoes, which may spread the infection further.

The National Environment Agency has stepped up search-and-destroy operations for mosquitoes in the area around Clive Street and the rest of Little India. Since Monday, it has inspected 1,520 premises and found nine breeding sites.

Chikungunya victim: It started with sharp pain in ankles
Indian national soon felt pain all over his joints, and had fever
Lee Hui Chieh, Straits Times 18 Jan 08;

TUESDAY started as a day of celebration but ended in crippling pain for Mr Vidwasekar Gnanasigamani, a 38-year-old farmer from Tamil Nadu, India.

He had come here nearly a month ago to visit friends, and Tuesday was when he was in Bedok with them to celebrate Pongal, a traditional harvest festival for Tamils to give thanks for the blessings of the past year.

While travelling on the bus to return to the Little India shophouse where he was staying, a sharp pain seared his ankles.

In 15 minutes, it spread to his knees, elbows and wrists.

It was so painful that he could barely walk to the shophouse after getting off the bus. A trek that should have taken five minutes took him half an hour.

He said in Tamil: 'I walked very slowly, and had to sit down and rest after a while before walking again.'

He did not know it then, but joint pain is a classic symptom of chikungunya, a dengue-like disease spread by the Aedes mosquito.

The disease gets its name from the word in the Makonde language meaning 'that which bends up', a reference to the stooped posture that patients adopt to compensate for the severe pain in their joints.

Makonde is spoken along the border between Tanzania and Mozambique, where the disease first surfaced in 1955.

Joint pains aside, Mr Vidwasekar also sprang a high fever, another symptom.

He is one of six people here, all foreign nationals in their 20s and 30s, who have been who have been diagnosed with chikungunya this month.

Five of them, including him, were staying in the same shophouse.

They were picked up only after a 27-year-old man from Bangladesh, the third among them to fall sick, went to see a general practitioner who suspected that he had either dengue or chikungunya and sent him for a blood test.

When the result was positive for chikungunya, the GP informed the Health Ministry, which sent its officers to investigate.

All six men were taken to the Communicable Disease Centre on Wednesday.

Only Mr Vidwasekar and another man from Bangladesh were admitted because tests showed that they still had the virus in their blood and were potentially infectious.

As there is no treatment for chikungunya, they were given drugs for the fever and pain, and fluids to prevent dehydration.

Only Mr Vidwasekar is still running a temperature.

The father of two sons aged four and seven had been planning to travel to Malaysia the day he fell sick.

He said: 'Now, I just want to get well soon and go back to India.'

Chikungunya strikes Singapore
Tan Hui Leng, Today Online 18 Jan 08;

A day after Today reported about studies being done here on a hitherto little-known viral disease, the Ministry of Health (MOH) announced that there are six confirmed cases of chikungunya fever, including the first likely case of local transmission.

A 27-year-old Bangladeshi man, who has not gone overseas for several months, has caught the virus the same way dengue is transmitted – through mosquitoes.

Prior to Monday, which was when MOH was notified, all cases of chikungunya reported here were contracted overseas. There were 10 such cases in Singapore in all of last year.

To keep the virus from gaining a foothold here, the National Environment Agency (NEA) is conducting intensive mosquito-control operations in the Clive Street area, where the patient resided, and will extend checks to cover Little India over the next few days.

All houses and shop premises are being checked and treated with insecticides, and inspections will carry on into the night, said the MOH and the NEA in a joint statement yesterday.

Meanwhile, screening done by the two agencies have found five other persons, all foreign nationals who have been in the country for at least a month, with chikungunya fever.

They have been sent to the Communicable Disease Centre for further medical assessment and two have been admitted for isolation.

Screening of residents and workers in the Clive Street area is continuing, even as investigations are in progress regarding the source of their infections.

"Unlike dengue, chikungunya is not an endemic disease in Singapore," said MOH's director of communicable diseases, Dr Lyn James.

This is why the authorities are stepping up protective measures.

An acute viral disease, chikungunya fever is caused by a virus of the same name. Symptoms include a sudden onset of fever, chills, headache, nausea, vomitting, and joint pain.

Some patients may develop a rash on the body and limbs. The illness is usually self-limiting and most symptoms last for three to 10 days.

The Bangladeshi man first developed symptoms of fever, body ache, joint pains and lethargy on Jan 8. Two days later, he sought treatment from a General Practitioner and a blood test showed that he had chikungunya. He is now being managed as an outpatient.

Another patient, Mr G Vidwasekar, who fell ill on Tuesday, told 938Live: "I was celebrating Pongal at my friend's place in Bedok. On my way back in a bus, I felt pain in my legs, mostly on my ankles. When I got off the bus, I felt very weak and could not walk at all. I had to walk and stop along the way. Normally I take five minutes to walk back, but that night, I took half an hour."

There is no specific drug treatment for the chikungunya virus and treatment usually includes bed rest, fluid replacement and medication for fever and pain relief. Hospitalisation may be required for more severe cases.

Currently, there is also no effective vaccine for chikungunya fever although the Singapore Immunology Network is working with the NEA and MOH to develop one, as TODAY had reported.

MOH and NEA has advised those who have been in the area recently and have developed a fever to consult their doctors.

"Like dengue fever, is a mosquito-borne disease and the best way to prevent chikungunya fever is to take precautionary measures to prevent mosquito breeding," said MOH and NEA in a joint press release yesterday.

"Persons infected with chikungunya fever should be isolated from further mosquitoes bites (by staying indoors and sleeping under a mosquito net during the first few days of illness) to reduce the risk of further transmission of the virus."

Like dengue, chikungunya fever is found in many countries. Recent outbreaks have occurred in Africa and as close to home as Malaysia and Indonesia.

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