Fresh approach needed to tackle dengue
OUT of the RM25 billion extra health allocation in the 2017 budget, RM80 million was earmarked to expand the National Community Health Empowerment programme to prevent and control mosquito-borne diseases.
This comes on the back of a worsening dengue problem, with an increasing number of cases recorded yearly since 1980. There were 120,836 cases in 2015, up from 43,346 cases in 2013 – an increase of 179%. From January to August this year, 71,590 cases were detected – 193 Malaysians have lost their lives.
However, is directing RM80 million to mosquito control the most effective use of these funds?
Most of the money will probably be spent on community education and fogging.
Fogging is highly visible and sends reassuring signals to the affected community. Unfortunately, studies looking at the effectiveness of fogging indicate that the method achieves little. To be effective, fogging must rapidly reduce the mosquito population by around 97% and be repeated regularly.
Many infective mosquitoes escape unharmed as they are often found indoors in homes, offices and enclosed spaces when the fogging teams pass by.
A lot depends on the diligence of the operator: machines can be poorly maintained; insecticide dosages can be incorrect, undermining effectiveness. Fogging can also give residents a false sense of security, leading to a complacent attitude towards ensuring that drains are covered and containers are emptied of stagnant water.
Mosquito control efforts, mainly based around fogging, are extremely expensive at RM6,700 per reported dengue case. Malaysia spends around RM310 million every year on these activities. This amount is the equivalent to the budget cuts experienced by the Ministry of Health in 2015 and 2016. About the same amount was allocated for the 1Malaysia Supplementary Food Programme for primary school pupils under the 2017 Budget.
There are a number of strategies available to reduce the breeding opportunities for mosquitos. Water-collecting litter, clogged drains and discarded tyres are particularly favoured by these insects.
Health authorities cannot hope to eliminate all breeding places in parks, empty land, buildings, building sites, blocked drains and septic tanks.
Health Minister Datuk Seri Dr S. Subramaniam said in 2014 that public apathy undermines effective dengue control efforts. Few people seem willing to give up 10 minutes each day to get rid of breeding sites around their homes and workspaces.
Theoretically, mosquito numbers could be reduced by infecting the males with a fertility-reducing bacteria (Wolbachia). Trials are taking place in Singapore, with plans for Malaysian field tests next year. A few years ago, “genetically sterile” male Aedes aegypti mosquitoes were released as part of viability tests to decrease the population of this insect. New mosquito traps are being developed. But the arrival on the scene of a new vaccine against dengue fever, calls into question the wisdom of pumping more money into mosquito control. This vaccine, Dengvaxia (CYD-TDV) was first licensed in Mexico in December 2015, which has now included it in their national immunisation programme.
Dengvaxia demonstrated significant levels of protection (57%) against dengue infection during clinical trials, which involved over 10,000 children in five Asian countries, including Malaysia.
The vaccine has since been licensed by nine other endemic countries including Singapore, Indonesia, Thailand and the Philippines. WHO has recommended countries to adopt the vaccine in national immunisation programmes, particularly for children aged between nine and 16 years.
Deputy Health Minister Datuk Seri Dr Hilmi Yahya stated earlier that the government is “still doubtful of the vaccine’s effectiveness, as such there is no need to register the vaccine in the country for the time being”.
What is clear is that approaches to mosquito control are both ineffective and costly. In light of tighter budget lines and the availability of more cost effective methods, perhaps it is time for the Ministry of Health to take on a fresh approach to fighting dengue.
Philip Stevens Senior Fellow Institute for Democracy and Economic Affairs