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.



India’s Monsoon Back on Track, Heatwave to Ease, Says Weather Officials 

School children use umbrellas to cover themselves from the rain as they walk to school, in New Delhi, India May 2, 2025. (Reuters)
School children use umbrellas to cover themselves from the rain as they walk to school, in New Delhi, India May 2, 2025. (Reuters)
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India’s Monsoon Back on Track, Heatwave to Ease, Says Weather Officials 

School children use umbrellas to cover themselves from the rain as they walk to school, in New Delhi, India May 2, 2025. (Reuters)
School children use umbrellas to cover themselves from the rain as they walk to school, in New Delhi, India May 2, 2025. (Reuters)

India's monsoon has revived after stalling for more than a fortnight, and rains are set to cover central parts of the country this week, bringing relief from the heatwave in the grain-growing northern plains, two senior weather officials said on Monday.

The monsoon, the lifeblood of the country's nearly $4 trillion economy, delivers nearly 70% of the rain that India needs to water farms and replenish aquifers and reservoirs.

Nearly half of India's farmland, which has no irrigation, depends on the annual June-September rains for crop growth.

The monsoon has revived after a fortnight as a favorable weather system has developed in the Bay of Bengal, which would help the monsoon to cover entire central India this week, an official of the India Meteorological Department (IMD) told Reuters.

Monsoon rains on Monday covered almost the entire western state of Maharashtra and entered into neighboring Gujarat and central state of Madhya Pradesh, the official said.

The Monsoon's onset over Kerala occurred on May 24 and quickly covered southern, northeastern and some parts of western India ahead of its usual schedule, but its progress has stalled since May 29, according to an IMD chart that tracked the monsoon's progress.

The monsoon has gained the required momentum, and heavy rainfall is likely over west coast, central and some parts of north India in next ten days, which will significantly bring down temperatures, another weather official said.

India has received 31% lower rainfall than average in the first half of June, but in the second half the country is set to receive above average rainfall, the official said.

Monsoon rains are set to progress quickly in the next few days and could cover most parts of the country before the end of June, the official said.

Summer rains usually fall in Kerala around June 1 before spreading nationwide by mid-July, allowing farmers to plant crops such as rice, corn, cotton, soybeans and sugarcane.