PETALING JAYA: The weather will be hotter and drier this year – making it ideal for the Aedes mosquito and the dengue fever it spreads, say experts.
Historically, they said, climate played a part in dengue transmission and higher cases were expected in 2023.
“Usually, there will be one peak in June or July and a smaller one in January or February,” said National Antarctica Research Centre climatologist Prof Datuk Dr Azizan Abu Samah.
“Since dengue is endemic, the environment, especially temperature, is correlated to the Aedes population. That is, an increase in temperature sees an increase in Aedes mosquitoes.”
He added that high-density areas such as Cheras were Aedes hotspots.
“Normally, dengue cases increase during El Nino years. Since we are going to El Nino-Southern Oscillation (ENSO) neutral for 2023, dengue cases are expected to increase compared with 2021 and 2022, which overall, were cooler years.
“The peak tends to follow the weather temperature cycle, not the rain cycle,” added Prof Azizan.
El Nino will bring about dryer and warmer weather.
Public health advocate Datuk Dr Zainal Ariffin agreed that the weather affected dengue transmission – therefore, higher cases were expected this year.
On how one can learn from the Covid-19 pandemic to manage dengue, which is endemic in several countries, he said this could be done through intensive health education, especially in hotspots.
Screening for dengue fever at hospitals and clinics was another way, he added.
Dr Zainal said regular checks at Aedes breeding grounds in housing and industrial sites were also important.
According to World Health Organisation (WHO) modelling, there is an estimated average of 390 million dengue virus infections per year, of which about 96 million are severe infections.
In terms of the number of actual cases reported, WHO said the number had increased over eight-fold in the last two decades, from 505,430 cases in 2000 to more than 2.4 million in 2010 and 5.2 million in 2019.
It also said 3.9 billion people were at risk of infection.
