No let-up in dengue infections

Dengue cases cross 200 mark for seventh consecutive week and are expected to rise over the next few months.
Dengue cases cross 200 mark for seventh consecutive week and are expected to rise over the next few months. ST PHOTO: JAMIE KOH

The number of dengue cases has crossed 200 for the seventh consecutive week, according to the latest figures released by the National Environment Agency (NEA) yesterday.

There were 212 cases reported in the week ending Aug 6. There were 40 cases in total on Aug 7 and Aug 8, as of 3pm.

While the latest weekly number is nine fewer than the previous week's, NEA said the dengue infection rate has been fluctuating in the same range for the past few weeks.

Moreover, the numbers are expected to rise over the next few months given that Singapore is now in its traditional peak dengue season, warned the agency.

Infectious diseases experts told The Straits Times that the latest figures are worrying, although it remains to be seen if the total number of dengue cases will exceed 30,000, which the authorities said was a possibility earlier this year.

The authorities warned at the start of the year that the total number of cases could exceed that in 2013, which saw more than 22,000 cases. There have been more than 10,300 cases so far this year.

"Every time there is a new case of dengue, this person becomes a suitable source of transmitting dengue," said Dr Leong Hoe Nam, an infectious diseases specialist at Mount Elizabeth Novena Hospital.

"The only way (to bring down the number of cases) is to get rid of Aedes aegypti mosquitoes," he said, adding that it is difficult as the chance of finding an Aedes aegypti mosquito with dengue is just 1 per cent.

The NEA's mosquito trap data has shown a steady rise in the number of Aedes aegypti mosquitoes since April this year.

Dengue fever usually develops four to seven days after a person has been bitten by a carrier mosquito. The virus has already claimed the lives of seven people this year.

The traditional peak dengue season in Singapore is from June to October, when the warmer weather speeds up mosquito breeding and maturation, said Dr Hsu Li Yang, head of the infectious diseases department at Tan Tock Seng Hospital.

"The rise in dengue cases is not unexpected because we are currently still within the usual dengue peak season in Singapore," said Dr Hsu. "Given that we are already in August, it is quite unlikely for the number of dengue cases to exceed 30,000 this year.

"Nonetheless, the case count is already higher than the average of previous years, so the mozzie wipeout measures are still important."

Dr Wong Sin Yew, an infectious diseases physician at Gleneagles Medical Centre, added: "Hopefully, it will not exceed 30,000... We hope that it can be below 20,000 by December 2016."

A version of this article appeared in the print edition of The Straits Times on August 11, 2016, with the headline 'No let-up in dengue infections'. Print Edition | Subscribe