Do Africans Want Genetically Modified Mosquitoes?

Mosquito sitting on a leaf

Utibe Effiong, MPH ’14

Physician, MidMichigan Health Medical Center, Mount Pleasant

A recent plan to release over 750-million genetically modified mosquitoes in Florida received final approval from local authorities a few weeks ago. While the proposal already had state and federal approval, the news received strong reactions from residents and environmental advocacy groups in the United States, who fear the effect on the ecosystem and public health.

The idea of genetically modifying mosquitoes (GMMs) as a strategy for controlling the diseases transmitted by these much-maligned insects might seem innovative. But scientists around the world have been fiddling with mosquitoes and other insects to increase disease control for decades.

There have been many releases of sterile insects around the world, with varying degrees of success in the control of pests.

In 1951, Bushland and Hopkins demonstrated that screwworm flies could be sterilized with x-rays, and by 1959 Edward Knipling had proposed the concept of releasing factory-produced sterile insects to control populations of certain pests. Since then, the sterile insect technique (SIT) has undergone substantial modification and now includes the production of transgenic insects. There have been many releases of sterile insects around the world, with varying degrees of success in the control of pests.

The genetically modified mosquitoes approved for release in Florida are another modification of the sterile insect technique. According to the approval notice issued by the US Environmental Protection Agency, the mosquito, named OX5034, has been altered to produce female offspring (which carry malaria) that die in the larval stage, well before hatching and growing large enough to bite and spread disease.

A Somewhat Quantitative Survey

The recent publication by fellow Nigerian scientists—Patricia Okorie and colleagues—originally drew my attention to the issue of GMMs. With over 100 million people at risk of malaria, dengue, and yellow fever, Nigeria has the largest burden of mosquito-borne diseases in Africa. But mosquito-control programs in Africa have seen little success because of insecticide resistance and difficulties in scaling up successful strategies such as the use of long-lasting insecticide-treated bed-nets.

Given that, Okorie and colleagues decided to consult other Nigerian researchers about alternatives. And the vast majority were skeptical about a potential release. Many expressed concerns that GMMs could spread in an uncontrolled manner beyond release sites. Other concerns were related to the production of hybrids with unknown consequences; the possibility that GMMs could transmit unknown diseases, be resistant to insecticides, harm ecosystems; and of course, the cost of such initiatives.

With further analysis, however, the Okorie team concluded that while a majority of participants were skeptical, most would encourage the strategy provided there were contingency measures to remove them if an unanticipated risk became evident during the release. Not surprisingly, Okorie’s study was criticized as not representing the views of Nigerian scientists. Georgina Mwansat, an entomologist at the University of Jos, noted that sampling only 164 researchers from two of Nigeria’s 36 states “is not enough to form an opinion on all of the scientists in the country.”

A Somewhat Qualitative Survey

I concur that, with a study conducted in a limited geographical and cultural space, it is likely Okorie heard from only a very small proportion of Nigeria’s more than 500 ethnicities. Okorie’s team may also have been talking to people from age groups that do not represent national public opinion. With a median age of 17.8 years and with widespread social media activity, it is likely a more general perspective on GMMs in Nigeria is shaped by people under 40.

This understanding informed my recent attempt to conduct an opinion sample among Nigerian users of social media. To be clear, this was not a quantitative scientific exercise, nor was it any kind of formal qualitative study. But I wanted to hear what young Nigerians from different ethnic groups in different vocations and regions thought about the use of GMMs to control malaria. My query received 46 comments from 20 Nigerians representing at least nine ethnic groups, in 12 vocations, living on 3 continents.

Several responses reflected religious-based views that are skeptical of scientific endeavors, especially genetic engineering. Some expressed concerns about the role of corrupt government officials in dealing with a potential GMM release in Nigeria.

The use of biotechnology to prevent human disease may be innovative and show promise. But it takes more than innovation to solve public health problems.

Most respondents were concerned about the balance of the ecosystem, one pointing out the outcome of mosquito eradication efforts in India, where a major resurgence of malaria occurred after Indian DDT applications were reduced in the 1970s. Others openly expressed a preference for chemical-based mosquito eradication to anything related to genetic modification. One thought it would be a good idea but reminded me that a malaria vaccine is on the verge of approval. Another pointed me in the direction of the mosquito repellants she distributes.

Several comments criticized the overall feasibility of the approach. Others wondered about financing such measures. One comment expressed the very African attitude that government and governance is top of mind over other concerns: “We’ll look into this matter after the elections.”

Better Policy and Governance

The use of biotechnology to prevent human disease may be innovative and show promise. But it takes more than innovation to solve public health problems. Sufficient policy work and broad public communication and participation are also necessary. For Nigerians and most people in the developing world, opportunities to participate in shaping policy around technologies and interventions that affect their lives must become more commonplace.

[GMM programs] must consider biological, environmental, sociopolitical, ethical, and cultural dimensions to be truly successful in enhancing public health.

Following the work led by Okorie, African scientists have continued to explore potential GMM programs. Regional consultations have been offered to inform the public about environmental risks associated with such interventions. And despite public health concerns about GMMs, the genetic modification of other tropical disease vectors, such as transgenic schistosome-resistant (TSR) snails, are now under consideration.

As an environmental health scientist, I agree with Coulibaly and colleagues. While GMM technologies offer opportunities for broad, inexpensive, safe, egalitarian, complementary vector control, such programs must consider biological, environmental, sociopolitical, ethical, and cultural dimensions to be truly successful in enhancing public health.

About the Author

Utibe Effiong, alum of Michigan Public Health and physician at the MidMichigan Health Medical Center in Mount PleasantUtibe Effiong, MD, MPH ’14 is an internal medicine physician, public health scientist, and clinical assistant professor of medicine at Central Michigan University. He is also a Senior Fellow at the Aspen Institute. Read more about Dr. Effiong in A Desire to Be More: How Public Health Connects Medicine to Patient Communities.


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