Geoengineering could return risk of malaria for one billion people


Date:
April 20, 2022
Source:
Georgetown University Medical Center
Summary:
Geoengineering the climate would have massive repercussions for
the health of billions of people at risk of malaria who live in
tropical countries, according to a new finding. This is the first
assessment of how geoengineering the climate could impact the
burden of infectious diseases.



FULL STORY ========================================================================== Geoengineering the climate would have massive repercussions for the
health of billions of people at risk of malaria who live in tropical
countries, according to a new finding by scientists at Georgetown
University Medical Center and colleagues. The study appeared April 20,
2022, in Nature Communications.


==========================================================================
This is the first assessment of how geoengineering the climate could
impact the burden of infectious diseases. The study focuses on solar
radiation management (SRM), an intervention that hypothesizes emergency
actions aimed at reducing dangerous impacts of climate change. One action
that has been proposed is injecting aerosols into the stratosphere
that reflect incoming sunlight, thereby temporarily "pausing" global
warming. Though SRM is often discussed as a way to reduce climate
injustice, its potential impacts on health have seldom been studied.

"The implications of the study for decision-making are significant,"
says Colin Carlson, PhD, an assistant research professor at the Center
for Global Health Science and Security at Georgetown University Medical
Center and lead author of the study. "Geoengineering might save lives,
but the assumption that it will do so equally for everyone might leave
some countries at a disadvantage when it comes time to make decisions. If geoengineering is about protecting populations on the frontlines of
climate change, we should be able to add up the risks and benefits -- especially in terms of neglected health burdens, such as mosquito-
borne disease." A team of eight researchers from the United States, Bangladesh, South Africa, and Germany used climate models to simulate what malaria transmission could look like in two future scenarios, with medium
or high levels of global warming, with and without geoengineering. The
models identify which temperatures are most conducive for transmission
by the Anophelesmosquito and identify how many people live in areas
where transmission is possible.

In both medium- and high-warming scenarios, malaria risk was predicted to
shift significantly between regions; but in the high warming scenario, simulations found that a billion extra people were at risk of malaria
in the geoengineered world.

"On a planet that's too hot for humans, it also gets too hot for
the malaria parasite," says Carlson. "Cooling the planet might be an
emergency option to save lives, but it would also reverse course on
those declines." The study follows a 2018 commentary in Nature Climate Changeby Carlson and the study's senior author, Christopher Trisos, PhD,
a senior researcher at the University of Cape Town in South Africa. In
the commentary, the researchers proposed a hypothesis now confirmed in
the new study: because malaria transmission peaks at 25DEGC, cooling the tropics using geoengineering might ultimately increase malaria risk in
some places relative to an alternative future, but might also increase
risk in the present day.

"The potential for geoengineering to reduce risks from climate change
remains poorly understood, and it could introduce a range of new risks
to people and ecosystems," says Trisos.

Carlson says that one of the most surprising findings was the scale of potential trade-offs between regions. For example, in both scenarios, the authors found that geoengineering might substantially reduce malaria risk
in the Indian subcontinent even compared to the present day. However,
that protective effect would be offset with an increase in risk in
southeast Asia.

For decision-makers, this might complicate the geopolitical reality of
climate intervention.

"We're so early in this process that the conversation is still about
increasing Global South leadership in geoengineering research. Our study highlights that the frontlines of climate injustice aren't one monolithic
bloc, especially when it comes to health," says Carlson.

Additional study authors also included collaborators from the University
of Maryland, College Park; the International Centre for Diarrhoeal
Disease Research, Bangladesh; the University of Florida, Gainesville; the Cologne University of Applied Sciences, Germany; and Rutgers University,
New Brunswick, New Jersey.

The authors report having no personal financial interests related to
the study.

Funding for the study was provided by the Solar Radiation Management
Governance Initiative (SRMGI) Developing Country Impacts Modeling Analysis
for Solar Radiation Management (DECIMALS) grant program.


========================================================================== Story Source: Materials provided by
Georgetown_University_Medical_Center. Note: Content may be edited for
style and length.


========================================================================== Journal Reference:
1. Colin J. Carlson, Rita Colwell, Mohammad Sharif Hossain, Mohammed
Mofizur
Rahman, Alan Robock, Sadie J. Ryan, Mohammad Shafiul Alam,
Christopher H.

Trisos. Solar geoengineering could redistribute malaria risk in
developing countries. Nature Communications, 2022; 13 (1) DOI:
10.1038/ s41467-022-29613-w ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2022/04/220420092126.htm

--- up 7 weeks, 2 days, 10 hours, 51 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)