Health director-general Dr Noor Hisham Abdullah said, however, that health authorities were ready with preventive measures and had taken steps to destroy Aedes breeding grounds in hotspots nationwide, particularly in the Klang Valley since April.
“The operation will be upgraded continuously to ensure Aedes mosquitoes do not breed when the country is facing the rainy season, especially with the coming La Nina phenomenon,” he told Bernama here.
He said a study conducted in Kuala Lumpur, Pahang, Kedah and Johor in 2011 revealed that the La Nina phenomenon and rain would further increase the risk of dengue infection following one week of rain.
There were also studies that correlated the relationship between the La Nina phenomenon with an increase in the incidence of dengue fever in other countries, he said.
“For example, a study conducted in 2016 showed a significant increase in the incidence of dengue cases in the Philippines when the La Nina phenomenon occurred in that country,” he said.
The La Nina phenomenon is associated with the amount of rainfall that exceeds normal rate and episodes of abundant and prolonged rain that increase water accumulation in places that can hold water in the surroundings, such as tree holes, leaves, bottles and tyres which are suitable for Aedes breeding.
To enhance the effectiveness of the preventive measures, Noor Hisham advised the people to be more aware of their home environment by ensuring there were no mosquito breeding grounds.
“Spend just 10 minutes to search and destroy Aedes breeding grounds and place abate to kill mosquito larvae in water containers or flower vases,” he said.
He said the Health Ministry was currently taking new measures to control mosquitoes, namely the Outdoor Residual Spray (ORS) technique.
“Normally fogging is done in the areas identified as dengue hotspots but the ORS method involved spraying on the wall of the premises, to kill the mosquitoes,” he said.
To deal with places that were not easily reached, Noor Hisham said insecticide fogging operations using ultra low volume (ULV) would be carried out.
It would include all dengue fever hotspots, especially in the Klang Valley for every two weeks, he said.
– BERNAMA