Rise in Dengue Type 2 virus cases

Patwant Singh Channel NewsAsia 29 Aug 14;

SINGAPORE: Dengue Type 2 virus cases are getting more common in Singapore. The proportion of the second most common type of dengue virus rose to 25 per cent of all dengue cases in August, from 15 per cent for the first eight months of this year.

Type 1 virus cases in August accounted for 73 per cent of all cases, compared to 82 per cent for the first eight months of this year.

The authorities have warned that should the Type 2 virus become more prevalent, the risk of an epidemic may increase as the immunity level for the Type 2 virus is lower.

"We hope that residents as well as Singaporeans will continue to protect themselves and protect their families. And ex-dengue patients should be aware that immunity against one type of virus does not bring you immunity for another type, so there is still a risk of picking up a different serotype. So we need to continue to watch out and be alert," said Ms Grace Fu, Second Minister for the Environment and Water Resources, and Minister in the Prime Minister's Office.

Ms Fu was making a site visit to the MacPherson dengue cluster on Thursday (Aug 28) to see the steps taken by the Marine Parade Town Council against mosquito breeding habitats. As of Aug 25, a total of 229 cases have been reported in Circuit Road, one of three dengue clusters in MacPherson. Four-fifths of the cases of dengue here are Type 2 virus cases and the rest are Type 1.

With Singapore still in the peak dengue season, the authorities are keeping a close watch on the situation.

- CNA/by

More DEN-2 cases, but too early to be considered serotype switch: Grace Fu
Today Online 28 Aug 14;

SINGAPORE — Contrasting with observations across the rest of Singapore, dengue serotype DEN-2 has been found to be the predominant strain of the virus among the cases reported in the Circuit Road cluster, presently the largest active cluster.

As of Monday (Aug 25), 229 dengue cases have been reported in the Circuit Road cluster, of which 80 per cent are dengue serotype DEN-2, and the rest are DEN-1.

This is the reverse of observations islandwide. DEN-1 took up a 82.4 per cent majority of cases across the island in the first eight months of this year, while DEN-2 took up 15.4 per cent. DEN-3 and DEN-4 cases took up trace proportions.

In August alone, however, DEN-1 saw a dip to 73 per cent while DEN-2 saw a spike to 25 per cent.

Still, it is too early to deem this a serotype switch, said Second Minister for Environment and Water Resources Grace Fu during a site visit to MacPherson dengue cluster this afternoon.

“It is too early to predict that this is a switch of serotype, but we will monitor the situation closely,” Ms Fu said.

A change in the predominant dengue serotype calls for concern because the population lacks immunity to this new circulating serotype. The last switch was observed in March last year, from DEN-2 to DEN-1.

Ms Fu called for residents to work closely with the town council and authorities, cautioning that they “should not let their guard down, even if (they) have had dengue before”.

During this afternoon’s site visit, Ms Png Chiew Hoon, general manager of Marine Parade Town Council, also shared how they have been working with residents to tackle dengue, such as by giving out insect repellents, increasing checks on drains and common corridors.

Meanwhile, the total number of dengue cases reported dipped to 421 last week (ending Aug 23) from 442 the previous week.

The National Environment Agency (NEA) said it has conducted two million inspections to date and will continue to focus on areas with high potential for dengue transmission, like construction sites. The NEA has also issued 71 Stop Work Orders and 14 contractors have been prosecuted in court for repeat offences