La Nina phenomenon next month expected to see increase in Dengue cases

KUALA LUMPUR: The La Nina phenomenon that brings excessive rain and expected to occur in the country from next month until October is likely to see an increase in dengue cases.
Health director general Datuk Dr Noor Hisham Abdullah said, however, the health authorities were ready with preventive measures and had taken steps to destroy Aedes mosquitoes 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 after it rained for a week.
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 mosquitoes 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 which kills 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 every fortnightly starting next week, he said.
Up till April 23, dengue statistics for the 16th week this week showed a decline of 13.3% or 1,607 cases nationwide from 1,854 cases in the previous week.
Only five states showed a rise in dengue cases - the Federal Territories of Kuala Lumpur and Putrajaya 32 cases (25.2%), Negri Sembilan 10 cases(55.6%), Kelantan six cases (14.6%), Perlis four cases (100%) and Pahang two cases (6.5%). — Bernama