US to Use Genetically Modified Mosquitoes to Fight Dengue Fever

Aedes aegypti mosquitoes are seen at the Laboratory of Entomology and Ecology of the Dengue Branch of the US Centers for Disease Control and Prevention in San Juan, March 6, 2016. (REUTERS/Alvin Baez)
Aedes aegypti mosquitoes are seen at the Laboratory of Entomology and Ecology of the Dengue Branch of the US Centers for Disease Control and Prevention in San Juan, March 6, 2016. (REUTERS/Alvin Baez)
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US to Use Genetically Modified Mosquitoes to Fight Dengue Fever

Aedes aegypti mosquitoes are seen at the Laboratory of Entomology and Ecology of the Dengue Branch of the US Centers for Disease Control and Prevention in San Juan, March 6, 2016. (REUTERS/Alvin Baez)
Aedes aegypti mosquitoes are seen at the Laboratory of Entomology and Ecology of the Dengue Branch of the US Centers for Disease Control and Prevention in San Juan, March 6, 2016. (REUTERS/Alvin Baez)

After a decade of discussions, officials in Florida have voted to allow the first test in the United States of free-flying, genetically modified mosquitoes that kill any female offspring, as a way to fight the pests and the diseases they spread.

The decision came after about two hours of contentious testimony in a virtual public hearing on August 18. Many speakers railed against uncertainties in releasing genetically engineered organisms. In the end, though, worries about mosquito-borne diseases proved more compelling.

On the day of the vote, dengue fever cases in the Florida Keys islands totaled 47 so far in 2020, the first surge in almost a decade.

The same mosquitoes known for yellow fever (Aedes aegypti) also spread dengue as well as Zika and Chikungunya. The species is especially hard to control among about 45 kinds of mosquitoes that whine around the Keys.

According to a report by the Science News website, the genetically modified mosquitoes plan will kick off in January, 2021. Florida workers will set out boxes of eggs of specially bred male yellow fever mosquitoes. The eggs will grow into normal-looking males, and like other male mosquitoes, they drink flower nectar, not blood.

Then planners hope that during tests, these Oxitec foreigners will charm female mosquitoes into mating. A bit of saboteur genetics from the males will kill any female offspring resulting from the mating, and over time that should shrink the swarms. Sons that inherit their dad's no-daughter genes will go on to shrink the next generation even further.

By now, Oxitec has supplied some billion saboteur male mosquitoes for release elsewhere around the world, especially in Brazil, where Zika can flare up and dengue is common.

The company believes that its successful trials in other regions around the world are a sufficient response to the objections surrounding its project. No potential harms on humans or environment have been observed in the locations where genetically modified mosquitoes were launched.



China Says its Astronauts Complete Record-breaking Spacewalk

File Photo: Astronaut Liu Yang waves as she is out of a return capsule of the Shenzhou-14 spacecraft, following a six-month mission on China's space station, at the Dongfeng landing site in Inner Mongolia Autonomous Region, China December 4, 2022. China Daily via REUTERS
File Photo: Astronaut Liu Yang waves as she is out of a return capsule of the Shenzhou-14 spacecraft, following a six-month mission on China's space station, at the Dongfeng landing site in Inner Mongolia Autonomous Region, China December 4, 2022. China Daily via REUTERS
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China Says its Astronauts Complete Record-breaking Spacewalk

File Photo: Astronaut Liu Yang waves as she is out of a return capsule of the Shenzhou-14 spacecraft, following a six-month mission on China's space station, at the Dongfeng landing site in Inner Mongolia Autonomous Region, China December 4, 2022. China Daily via REUTERS
File Photo: Astronaut Liu Yang waves as she is out of a return capsule of the Shenzhou-14 spacecraft, following a six-month mission on China's space station, at the Dongfeng landing site in Inner Mongolia Autonomous Region, China December 4, 2022. China Daily via REUTERS

Two Chinese astronauts this week completed a world-record spacewalk of more than nine hours, according to a statement from China's Manned Space Agency, marking another milestone for Beijing's rapidly expanding space program.

The spacewalk, carried out by Cai Xuzhe and Song Lingdong outside the Tiangong space station in low-Earth orbit on Tuesday, was at least four minutes longer than the last record set by NASA astronauts James Voss and Susan Helms in 2001, according to Reuters.

The two astronauts of China's Shenzhou-19 mission donned their Feitian spacesuits to carry out an array of tasks on the station's exterior, including the installation of space-debris protection devices, China's space agency said.

"They successfully completed all the planned tasks and felt very excited about it," Wu Hao, a staffer from the China Astronaut Research and Training Center, told China Central Television, a state broadcaster.

The former Soviet Union in 1965 became the first nation to carry out a spacewalk. Since then, Russia and the United States have conducted hundreds of such missions, primarily outside the International Space Station for tasks ranging from solar panel installations to materials research.

The first spacewalk by a Chinese astronaut occurred in 2008.

China's spacewalking milestone this week comes amid a flurry of other recent cosmic achievements that have boosted Beijing's competitive footing with the United States.

China landed its first rover on Mars in 2021 and earlier this year became the first country to retrieve rock samples from the moon's treacherous far side in its Chang'e-6 mission.

Beijing is targeting 2030 to land its first astronauts on the moon to become the second country after the US to put humans there. Beijing has courted roughly a dozen countries for its International Lunar Research Station program, an effort to build a moon base on the moon's south pole.

That program rivals NASA's Artemis program, which aims to return US astronauts to the moon for the first time since the final Apollo mission of 1972.