Upholding public trust in Aedes battle

Plan to release mosquitoes infected with Wolbachia to reduce dengue infection


Deputy Prime Minister (DPM) Datuk Seri Dr Wan Azizah Wan Ismail recently announced that the government will be launching an operation to release mosquitoes infected with Wolbachia in 10 localities in July to boost control of dengue.

The mosquitoes to be released are not genetically modified and are only infected with Wolbachia, a natural bacterium present in 60% of all species of insects.

It sounds like great news: The measure follows the success of a pilot project which was carried out in 2017, when four million Wolbachia-infected Aedes mosquitoes were released in five localities in Shah Alam, Selangor, and Keramat in Kuala Lumpur. The results of the pilot project showed a decrease of 60% to 70% of dengue cases in the areas.

The only problem is — where can us, the rakyat get more information, clarifications or raised questions or even doubts about this operation?

After a quick search on the web, I realised that the only official information available online is from the Medical Entomology Unit of the Institute of Medical Research which conducted the pilot project since 2016 at two initial sites (AU2 Keramat and Section 7 in Shah Alam).

While it is a great start to reach out to the public, I still feel that the information on the website is a one-sided conversation where the scientists deliver the facts; the public receives the facts.

There is lack of a platform there among the public, scientists and policymakers to interact actively (eg a pop-up feedback form, a live chat or a science media centre for public discourse).

The site only feeds the readers with the six basic ingredients of the five Ws (who, what when, where and why) and an H (how) with a generous amount of benefits derived from the trials.

However, I personally feel that the risk communication of the project is left out even though there are a lot of details on the advancement of technology applied in the Wolbachia project.

Now, technology is a fickle friend: It can take away value as well as add it. For example, the technology that has given us cheap energy has also given us carbon dioxide that will overheat the planet.

While the fickleness of technology can be a problem, the key failures have been due to lack of regulation. And regulation requires good governance.

Hence, the public needs to understand the risks and uncertainties relevant to the decisions made by the government and the scientific community.

We need to know and trust that the government will monitor this operation to reduce the potential risk which might occur later.

Will we be expecting any challenges in the form of mosquito and movements (eg how far and high they fly, and how well they could compete with their wild counterparts to mate with females?)

Is there a difference method applied in the operation between the landing and high-rise buildings?

Now, what about the risks? Mosquitoes have been here longer than humans have. What are the ramifications if we eradicate certain specific species of mosquitoes from the Malaysian ecosystem?

Once we significantly reduce the population of targeted mosquitoes, would this approach disrupt the food web?

This question is raised because mosquitoes, in their larval or adult forms, are a primary food source for various species of fish, aquatic insects, flying insects, birds, amphibians, reptiles and bats and they are also pollinators.

Wiping out a species of mosquito could leave a predator without prey, or a plant without a pollinator and this means we are breaking the food chain.

In addition, an article in Nature references the number of migratory birds that nest in the Arctic tundra could drop by more than 50% without mosquitoes to eat.

If there is no food, these animals are not able to think to get another food, and therefore they will have to adapt or die.

We could cause something that we can’t control in terms of their population changes.

All these information are vital for the welfare of the community and the protection of the environment and biodiversity, as once they are gone, they are gone for good.

An article in the Nature quoted Phil Lounibos, an ecologist at the Florida Medical Entomology Laboratory in Vero Beach, who says that “eliminating mosquitoes would temporarily relieve human suffering”.

His work suggests that efforts to eradicate one vector species would be futile, as its niche would quickly be filled by another.

His team collected female yellow-fever mosquitoes (Aedes aegypti) from scrap yards in Florida and found that some had been inseminated by Asian tiger mosquitoes (Aedes albopictus), which carry multiple human diseases.

The insemination sterilises the female yellow-fever mosquitoes — showing how one insect can overtake another. So, how long the Wolbachia method of control will be effective as many control measures become less effective over time. For example, many insect pests have shown increasing resistance to chemical insecticides.

Just to be clear, what I am communicating here is by no means an argument against the scientific consensus of Wolbachia and the biological control of mosquito-borne disease; nor is it an argument against communicating facts — or even values, for that matter.

Rather, it is a call for a greater public understanding in science and technology. We need to bridge the gap among the policymakers, scientists and the rakyat. Public understanding of science is driven not just by knowledge of facts, but also by individuals’ trust in the scientific community and the relevant authorities.

In my opinion, the announcement of the national operation is an exemplary of a deficit model (DM) which is a term from the field of Science and Technology Studies, used to describe initiatives or projects that are based upon a belief in the public’s lack of knowledge and scientific literacy and seek to remedy it by providing more, and correct information.

However, a large body of literature has now identified significant problems with the DM, which is monologic (one-way flow of information) and is regarded as the lowest level of communication.

The problems will then undermine the aims of organisers or authorities, thus limiting the efficacy of efforts to communicate with the public.

Yes indeed, so far, the Malaysians trust that the DPM had made the right decision after consulting the experts or scientific authorities who sit in the national-level committee on dengue.

However, the project proponent and federal government need to be as transparent as possible with regards to this operation and continue to share relevant information with the rakyat before we distrust the scientific solution.

  • Noor Asmaliza is a trained science communicator from National University of Singapore and the Australia National University. She has worked in a national think tank in science, technology and innovation. The views expressed are of the writer and do not necessarily reflect the stand of the newspaper owners and editorial board.