The Jerusalem Post

COVID isn’t spread by mosquitoes, but the next pandemic might be

- • By DAVID LAZARUS

Omar Akbari, an associate professor of cell and developmen­tal biology at UC San Diego, admits he loses sleep thinking about the next pandemic and how it could be so much worse than COVID-19.

“When COVID first happened, labs quickly tested to see if it could be borne by mosquitoes,” he told me. “Thankfully, it wasn’t. But imagine if it was.”

If so, the global death toll “could have been ten-fold, a hundred-fold worse,” Akbari said. That is, instead of looking at nearly four million COVID-19 fatalities worldwide, as is now the case, we’d be looking at as many as 400 million dead.

“It’s a scary thought,” said Akbari, one of the country’s foremost mosquito researcher­s. “Mosquitoes are the ultimate pathogen-transmissi­on machines. They’re really, really good at it.”

A circuitous path led me to his doorstep. I came across a press release from the pest-control company Terminix.

It featured a list of “the top cities in the United States that were most interested in finding out more about mosquitoes,” based on Internet searches last year.

What got my attention was that the top city for mosquito queries wasn’t a destinatio­n built on swamp land, such as Chicago, New Orleans and, I suspect, all of Florida. It was Bakersfiel­d, California.

Then I found a recent press release from another pest control business, Orkin, naming Los Angeles as the most mosquito-infested city in the country.

That puts LA ahead of boggier metropolis­es such as Atlanta – the most mosquito-infested city for the previous seven years – Washington and Dallas.

Intrigued, I decided to reach out to mosquito experts to find out if California in general and LA in particular are facing a mosquito menace perhaps few of us may be aware of.

The answer, I’m sorry to say, is yes. And its name is

According to the Centers for Disease Control and Prevention, the Aedes mosquito, aka the yellow fever mosquito, is “the main type of mosquito that spreads Zika, dengue, chikunguny­a and other viruses.”

“Because Aedes aegypti mosquitoes live near and prefer to feed on people, they are more likely to spread these viruses than other types of mosquitoes,” the CDC warned.

And here’s the bad news: The tropical Aedes mosquito is believed to have settled in California in 2013, likely after arriving aboard a cargo ship. It’s been thriving and spreading ever since.

“The danger that poses is significan­t,” Akbari said. “Unlike other mosquitos, which may only come out at dusk, Aedes is a daytime mosquito, and it likes to feed on humans.”

You’ll know it when you see it. It’s a dark, Darth Vadery-looking insect with white bands.

Anthony A. James, a professor of molecular biology and biochemist­ry at UC Irvine, told me the Aedes mosquito previously had a tough time gaining a foothold in California “because winters were cool and long enough to challenge their survival.”

“As things have warmed up, it is not as challengin­g for them,” he said. “Combining this with the human-driven availabili­ty of water from landscapin­g, agricultur­al use and small containers in yards, we have essentiall­y created an ideal environmen­t for them.”

Thanks, climate change!

EVERY MOSQUITO maven I spoke with told me the same. Our warming environmen­t is like Christmas for the Aedes mosquito, providing the aggressive, bloodthirs­ty little creatures with ideal circumstan­ces in which to proliferat­e.

“As the climate becomes warmer, we run the risk that these mosquitoes will spread into new areas, and with that the increased potential of mosquito-borne disease,” said Ryan C. Smith, an associate professor of entomology at Iowa State University.

He cited the Aedes mosquito’s “strong human preference­s” and the fact that they’re “aggressive daytime biters.”

“While for the time being this is just a nuisance,” Smith said, “it is important from the perspectiv­e that these mosquito species have the potential to transmit a wide range of mosquito-borne viruses.”

He cited an outbreak of the Zika virus in Florida in 2016.

Zika has been linked to birth defects, brain disorders and other illnesses.

“Aedes aegypti in Florida were able to promote Zika virus transmissi­on in and around Miami once it was introduced by human travel,” Smith said.

Which brings us back to COVID-19. As Akbari said, researcher­s wasted little time trying to determine if the virus could be spread by mosquitoes, including Aedes aegypti.

The conclusion, as reported a year ago in the scientific journal is that it can’t, “even in the unlikely event that a mosquito fed upon a viremic host.”

But Akbari and other specialist­s say we aren’t in the clear. Next time, they say, things could be different.

“As Aedes aegypti becomes more and more prevalent,” Akbari told me, “we could see transmissi­on of more and more pathogens.”

Basically, it’s just a matter of chance.

“If a person infected with the dengue virus or another virus transmitte­d by these mosquitoes were to come to California, and that individual was bitten, then it is possible that diseases such as dengue could then be spread,” said Craig Montell, a professor of molecular, cellular and developmen­tal biology at UC Santa Barbara.

“Dengue causes a wide spectrum of disease,” says the World Health Organizati­on. While many people infected with the virus experience only flu-like symptoms, severe cases can lead to bleeding, organ impairment and death. What can we do?

“That’s a tough one,” replied Jason L. Rasgon, a professor of entomology and disease epidemiolo­gy at Penn State. “Aedes aegypti are pretty difficult to eradicate.”

He suggested targeting their breeding sites, which tend to be any body of water near their favorite food (you and me). “The thing is,” Rasgon observed, “they don’t need a lot of water – very little, actually – so that can be hard.”

Akbari said pesticides are a possibilit­y, but they can be harmful to other insects we have no quarrel with, such as honey bees. Also, the Aedes mosquito, hardy little bugger that it is, probably would develop resistance to any chemicals we throw at it.

A better solution, Akbari said, may be to fiddle with the genome of the mosquitoes, introducin­g sterile males into the population or other approaches that battle the bugs on a molecular level.

“We need to develop new technologi­es,” he said. “What we have at the moment is not working.”

Now he’s not the only one losing sleep.

(Los Angeles Times/TNS)

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