Dengue numbers have been relatively low this year, with between 100 and 300 new cases a week. This is nowhere near the 700-plus new weekly infections seen at times in 2013 and last year.
But this could well change in the near future after 361 cases were diagnosed last week - the highest weekly total this year.
This is unusual as the end of the year is generally a low period for dengue infections.
The National Environment Agency said the number of Aedes mosquitoes is higher than normal due to the warmer than usual year-end weather, which promotes faster breeding and maturation.
Even more worrying is the emergence of the Den-1 strain, which has been relatively dormant here in recent years. There are four dengue strains. Unlike other infectious diseases, getting infected with one dengue strain does not confer immunity against the other three.
This means that many people who were infected recently have no immunity against this strain, and could get infected again.
The people most at risk are the youth and young adults. Last year, roughly one in 250 people here aged 15 to 44 years fell ill with dengue. About two out of three were male.
Singapore might be at the start of a dengue upswing. But if everyone cooperates by assiduously checking for mosquito breeding, we could nip the outbreak in the bud. So far this year, four people have died of dengue, and 10,265 have fallen ill from a simple mosquito bite. These deaths and illnesses, including many cases who needed to be hospitalised, could have been prevented.
Most mosquito breeding is found in homes, in containers and flower pot plates and trays. So, we cannot conveniently blame construction sites for the increase in mosquitoes.
Anyone who gets dengue knows the fault lies within the neighbourhood, because mosquitoes do not fly very far from their hatching ground.