The New Humanitarian Annual Report 2021

  1. Home
  2. Asia
  3. Thailand

Wiping out mosquito-borne diseases - with mosquitoes

Malaria mosquito.
The spread of malaria is being blamed on climate change (Swiss Radio)

Scientists fighting mosquito-borne diseases are racing to obtain approval to release genetically modified insects designed to stop the spread of dengue, a potentially fatal virus.

However, such moves have made environmentalists nervous as a science long used in agriculture is applied to public health.

These mosquitoes are engineered with an extra gene or inserted bacterium or have had a gene altered so that either their offspring are sterile and unable to spread dengue, or simply die.

"People generally do not like the unknown and are alarmist. Because there has never been a [field] release of GM [genetically modified] mosquitoes, critics are free to imagine what can possibly go wrong," said UK-based entomologist and professor at Imperial College London, John Mumford.

He is also the principal investigator for the World Health Organization (WHO)-funded regulatory group, Mosqguide, founded to develop best practices for deploying genetically modified mosquitoes to fight mosquito-borne diseases, primarily dengue and malaria.

For half a century, scientists have released billions of engineered insects - for example, fruit flies - to save plants, but to date there has not been a field release of insects engineered to save humans.

The Malaysia-headquartered NGO Pesticide Action Network-Asia and the Pacific opposed a since-granted request to release modified mosquitoes on the grounds that "it may have environmental or health consequences as well as carry risks arising from horizontal gene transfer", wrote executive director, Sarojeni V. Rengam, who stressed the "possibility of new health risks to humans and animals....the insect may become more virulent, aggressive, or its bite might have different effects on the host."

According to the Malaysian Health Ministry, 37,419 dengue cases were reported from January to 2 October, an increase of 17 percent on the same period last year.

Balancing act

If fish eat the larvae of modified mosquitoes and people eat the fish, one fear is how this diet may affect people, Mumford explained. "But we are forgetting that people eat modified corn and soybeans," he said.

"We have to look at the balance of risks. The risk of not controlling dengue is well-known. People die without better vector control... We need to move from worrying about risks to looking at public health benefits and addressing these risks," Mumford added.

The WHO estimates at least 50 million people worldwide are infected with dengue annually, with the number of cases doubling in the past decade and 70 percent of them recorded in Asia.

Australian researchers from the University of Queensland, funded by the Bill & Melinda Gates Foundation, have received regulatory approval to begin in December to release mosquitoes infected with a bacterium that prevents the dengue virus from multiplying, as has the Malaysian Ministry of Health.

In addition, Brazil, Panama, the US, Italy and Sudan are at varying stages in fighting mosquito-borne diseases with mosquitoes. "There are a lot of competing strategies, which is a good thing," said Mumford.

Mosqguide is cataloguing these different approaches and expects to publish case studies over the next year.


This article was produced by IRIN News while it was part of the United Nations Office for the Coordination of Humanitarian Affairs. Please send queries on copyright or liability to the UN. For more information:

Share this article
Join the discussion

Right now, we’re working with contributors on the ground in Ukraine and in neighbouring countries to tell the stories of people enduring and responding to a rapidly evolving humanitarian crisis.

We’re documenting the threats to humanitarian response in the country and providing a platform for those bearing the brunt of the invasion. Our goal is to bring you the truth at a time when disinformation is rampant. 

But while much of the world’s focus may be on Ukraine, we are continuing our reporting on myriad other humanitarian disasters – from Haiti to the Sahel to Afghanistan to Myanmar. We’ve been covering humanitarian crises for more than 25 years, and our journalism has always been free, accessible for all, and – most importantly – balanced. 

You can support our journalism from just $5 a month, and every contribution will go towards our mission. 

Support The New Humanitarian today.

Become a member of The New Humanitarian

Support our journalism and become more involved in our community. Help us deliver informative, accessible, independent journalism that you can trust and provides accountability to the millions of people affected by crises worldwide.