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Polio Was Almost Eradicated. This Year It Staged a Comeback.

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Polio Was Almost Eradicated. This Year It Staged a Comeback.

Firstly of this 12 months, there was a thrum of pleasure amongst world well being specialists: Eradication of polio, a centuries-old foe that has paralyzed legions of kids across the globe, appeared tantalizingly shut.

Pakistan, certainly one of solely two nations the place wild poliovirus nonetheless circulates, had not recorded circumstances in additional than a 12 months. Afghanistan had reported solely 4.

However eradication is an uncompromising objective. The virus should disappear from each a part of the world and keep gone, no matter wars, political disinterest, funding gaps or conspiracy theories. New indicators of the virus in a single nation can derail the hassle.

In polio’s case, there have been a number of ominous setbacks.

Malawi in February introduced its first case in 30 years, a 3-year-old lady who grew to become paralyzed following an infection with a virus that gave the impression to be from Pakistan. Pakistan itself went on to report 14 circumstances, eight of them in a single month this spring.

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In March, Israel reported its first case since 1988. Then, in June, British authorities declared an “incident of nationwide concern” once they found the virus in sewage. By the point New York Metropolis detected the virus in wastewater final week, polio eradication appeared as elusive as ever.

“It’s a poignant and stark reminder that polio-free nations should not actually polio-risk free,” stated Dr. Ananda Bandyopadhyay, deputy director for polio on the Invoice & Melinda Gates Basis, the biggest supporter of polio eradication efforts.

The virus is at all times “a aircraft journey away,” he added.

Polio is a extremely contagious and generally lethal enemy, able to ravaging the nervous system and inflicting paralysis inside hours. Those that get well might relapse and turn out to be critically unwell years later.

The virus multiplies within the gut for weeks and will unfold by means of feces or contaminated meals or water — for instance, when an contaminated little one makes use of the bathroom, neglects washing fingers after which touches meals.

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For many years the virus terrorized households, inflicting paralysis amongst greater than 15,000 American kids every year and lots of of 1000’s extra worldwide. Its retreat is a triumph of vaccination. After the primary vaccine arrived in 1955, the variety of circumstances dropped precipitously, and by 1979 the USA was declared polio-free.

Though the USA and Britain have excessive immunization charges, additionally they have pockets of low immunity that permit the virus to flourish. In these communities, all unvaccinated folks — not simply kids — are in danger. If polio continues to unfold in the USA for a 12 months, the nation could lose its polio-free standing beneath W.H.O. tips.

The Covid-19 pandemic left many different nations weak to a resurgence of polio: It disrupted vaccination drives for months and diverted employees and assets away from prevention packages, ensuing within the worst backslide in immunization charges in 30 years.

“The second you’re taking your eye off the ball, you realize that the virus will merely reappear,” stated Aidan O’Leary, director for polio eradication on the World Well being Group. “We now have to actually face down each single chain of transmission that we will determine.”

Support organizations first aspired to eradicate polio in 1988 and poured billions of {dollars} into the World Polio Eradication Initiative, a consortium of six companions, together with the Gates Basis, the W.H.O. and the Facilities for Illness Management and Prevention.

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Regardless of the latest circumstances, the progress is unmistakable: World circumstances of polio have fallen by 99 % — from 350,000 circumstances of paralysis in 1988 to about 240 thus far this 12 months.

That success “is each a miraculous factor and a factor that’s taken approach, approach longer than folks anticipated,” stated Invoice Gates, who has taken a pointed curiosity in polio, in an interview in February. “Eradications are tremendous arduous, they usually hardly ever must be undertaken.”

Ending polio has been significantly difficult.

There are three strains of the wild poliovirus. Sort 2 was declared eradicated in 2015, and Sort 3 in 2019. Solely Sort 1 poliovirus stays at giant, and solely in Pakistan and Afghanistan.

Till not too long ago, there was good purpose to be optimistic about Sort 1’s demise. India and Nigeria had been each thought-about inconceivable targets for polio elimination, however each achieved that objective.

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“There have been so many individuals who saved telling us you’ll by no means achieve India,” stated Dr. Hamid Jafari, W.H.O.’s director of polio eradication for the jap Mediterranean area.

Afghanistan and Pakistan have confirmed harder due to their nomadic populations, tough terrain and the baseless notion that the vaccine is a Western device for sterilizing the inhabitants, Dr. Jafari stated.

In Afghanistan, polio thrived in areas the place immunization bans had been imposed by the Taliban. In late March, the Taliban allowed vaccinations to renew, however the doses are administered in door-to-door campaigns, typically by feminine well being care employees. Some have been assaulted and killed.

Just one human viral illness, smallpox, has ever been eradicated. For all its deadliness, smallpox was comparatively easy to dispatch as a result of each an infection resulted in dramatic, unmistakable signs.

Polio is way more sly: It could unfold silently, inflicting delicate flulike signs or none in any respect, and but the illness paralyzes certainly one of each 200 contaminated kids. Even one case of paralysis is a sign that there could also be lots of and even 1000’s of undetected infections.

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“Paralysis is the tip of the iceberg,” stated Dr. Walter Orenstein, affiliate director of the Emory Vaccine Heart and a former director of the USA’ Immunization Program.

However in some nations, polio has turn out to be such a dim and distant risk that well being officers have stopped searching for it. Whereas Britain and Israel monitor sewage for the virus — splendid as a result of polio spreads by means of fecal matter — many others, together with these in the USA, have ceased energetic surveillance.

“There’s little doubt that there are locations the place it must be strengthened,” stated Dr. Matshidiso Moeti, W.H.O.’s regional director for Africa.

The one case imported into Malawi from Pakistan resulted in mass immunizations of practically 28 million kids in Malawi and its neighbors. However well being care employees had turn out to be unaccustomed to door-to-door campaigns.

Within the Chikwawa district in southern Malawi in March, Charles Bizimaki woke at 5 a.m., took the lunch his spouse had packed for him and walked a number of kilometers to a close-by village. Mr. Bizimaki has been the vaccine supervisor for six villages since 2007.

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However he had not carried out a door-to-door vaccination marketing campaign since a tetanus outbreak in 2013 and had by no means led one for polio.

The marketing campaign was bodily exhausting and irritating as a result of it generally took a number of visits earlier than he might discover a little one at residence. “It was not a straightforward job,” Mr. Bizimaki stated. It took him six days to vaccinate each little one beneath 5 within the close by villages.

Immunization for polio will be completed in certainly one of two methods. The injected vaccine utilized in the USA and most wealthy nations accommodates killed virus, is powerfully protecting in opposition to sickness however doesn’t stop the vaccinated from spreading the virus to others.

Mass vaccination campaigns depend on the oral polio vaccine, which delivers weakened virus in just some drops on the tongue. The oral vaccine is cheap, simple to manage and might stop contaminated folks from spreading the virus to others, a way higher suited to extinguishing outbreaks.

However it has one paradoxical flaw: Vaccinated kids can shed the weakened virus in feces, and from there it may possibly generally discover its approach again into folks, often setting off a series of infections in communities with low immunization charges.

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If the weakened virus circulates for lengthy sufficient, it may possibly slowly mutate again right into a extra virulent kind that may trigger paralysis.

Whilst wild poliovirus has been on the decline, so-called vaccine-derived polio has been on the upswing. Instances tripled between 2018 and 2019, and once more between 2019 and 2020. Between January 2020 and April 2022, 33 nations reported a complete of practically 1,900 circumstances of paralysis from vaccine-derived polio.

The samples present in London sewage, in Israel and in New York are all vaccine-derived virus. They carry the identical genetic fingerprint, suggesting that the virus could have been circulating undetected for a few 12 months someplace on the earth.

Eradicating polio would require wiping out the vaccine-derived sort, not simply the few remaining scorching spots of untamed virus. “We undoubtedly have to cease all polio transmission, whether or not wild poliovirus or whether or not circulating vaccine-derived poliovirus,” stated John Vertefeuille, who heads polio eradication on the C.D.C.

Vaccine-derived polio has turn out to be extra prevalent as a result of the oral vaccine in use now protects in opposition to solely Varieties 1 and three of the virus. In 2016, buoyed by the seeming eradication of Sort 2 virus, the W.H.O. withdrew it from the oral vaccine. That transfer left the world more and more weak to outbreaks of residual Sort 2 virus.

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On the identical time, world well being organizations shifted away from sustaining nimble groups that may swiftly stamp out outbreaks to strengthening well being care methods total. Areas that wrestle to include polio are likely to produce other public well being issues, equivalent to poor diet, entry to secure consuming water and different infectious illness outbreaks.

However the response to an outbreak of polio — or to different infectious ailments like Covid-19 or monkeypox — requires devoted groups and packages, stated Kimberly M. Thompson, a well being care economist whose work focuses on polio eradication.

The W.H.O. has not delivered on that objective for many years, “however there is no such thing as a accountability for efficiency,” Dr. Thompson stated. Likewise, nations that obtain funding for polio are hardly ever held liable for diverting the cash to different packages, she added.

Because of the dismantling of outbreak groups, the response to vaccine-derived polio has typically been sluggish and inefficient.

“The velocity and the standard of the responses must go up to ensure that us to cease these outbreaks,” Dr. Vertefeuille stated.

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In November 2019, the W.H.O. granted an emergency use authorization for a novel oral vaccine that’s particular to the Sort 2 virus. The vaccine, which took a decade to develop, is extra genetically secure than the extensively used oral vaccine and fewer prone to revert to a kind that may trigger paralysis.

The eventual objective for polio eradication is to immunize kids in each nation with the injected vaccine utilized in the USA, stated Jalaa’ Abdelwahab, director of vaccine packages at Gavi, which helps improve immunizations in poor nations. Provides of oral vaccine could be stockpiled solely to reply to surprising outbreaks, Mr. Abdelwahab stated.

The latest circumstances have compelled a reassessment of the methods getting used to detect and include polio. The C.D.C. is planning to introduce wastewater surveillance at strategic websites within the nation, in keeping with an announcement from the company.

Pakistan has among the many largest wastewater surveillance methods for polio, however vaccine hesitancy is rampant. One workforce of scientists, led by Dr. Jai Das at Aga Khan College in Karachi, has discovered that providing communities an incentive — putting in water pumps, for instance — in the event that they elevate vaccination charges could also be more practical than unconditional money prizes for people.

Eradicating polio by 2026, the present objective, would require modern methods, persistence and persistence — and an estimated $4.8 billion.

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“That final mile, these final circumstances, are at all times the toughest,” stated Simon Bland, chief government officer of the World Institute for Illness Elimination.

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Opinion: America's 'big glass' dominance hangs on the fate of two powerful new telescopes

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Opinion: America's 'big glass' dominance hangs on the fate of two powerful new telescopes

More than 100 years ago, astronomer George Ellery Hale brought our two Pasadena institutions together to build what was then the largest optical telescope in the world. The Mt. Wilson Observatory changed the conception of humankind’s place in the universe and revealed the mysteries of the heavens to generations of citizens and scientists alike. Ever since then, the United States has been at the forefront of “big glass.”

In fact, our institutions, Carnegie Science and Caltech, still help run some of the largest telescopes for visible-light astronomy ever built.

But that legacy is being threatened as the National Science Foundation, the federal agency that supports basic research in the U.S., considers whether to fund two giant telescope projects. What’s at stake is falling behind in astronomy and cosmology, potentially for half a century, and surrendering the scientific and technological agenda to Europe and China.

In 2021, the National Academy of Sciences released Astro2020. This report, a road map of national priorities, recommended funding the $2.5-billion Giant Magellan Telescope at the peak of Cerro Las Campanas in Chile and the $3.9-billion Thirty Meter Telescope at Mauna Kea in Hawaii. According to those plans, the telescopes would be up and running sometime in the 2030s.

NASA and the Department of Energy backed the plan. Still, the National Science Foundation’s governing board on Feb. 27 said it should limit its contribution to $1.6 billion, enough to move ahead with just one telescope. The NSF intends to present their process for making a final decision in early May, when it will also ask for an update on nongovernmental funding for the two telescopes. The ultimate arbiter is Congress, which sets the agency’s budget.

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America has learned the hard way that falling behind in science and technology can be costly. Beginning in the 1970s, the U.S. ceded its powerful manufacturing base, once the nation’s pride, to Asia. Fast forward to 2022, the U.S. government marshaled a genuine effort toward rebuilding and restarting its factories — for advanced manufacturing, clean energy and more — with the Inflation Reduction Act, which is expected to cost more than $1 trillion.

President Biden also signed into law the $280-billion CHIPS and Science Act two years ago to revive domestic research and manufacturing of semiconductors — which the U.S. used to dominate — and narrow the gap with China.

As of 2024, America is the unquestioned leader in astronomy, building powerful telescopes and making significant discoveries. A failure to step up now would cede our dominance in ways that would be difficult to remedy.

The National Science Foundation’s decision will be highly consequential. Europe, which is on the cusp of overtaking the U.S. in astronomy, is building the aptly named Extremely Large Telescope, and the United States hasn’t been invited to partner in the project. Russia aims to create a new space station and link up with China to build an automated nuclear reactor on the moon.

Although we welcome any sizable grant for new telescope projects, it’s crucial to understand that allocating funds sufficient for just one of the two planned telescopes won’t suffice. The Giant Magellan and the Thirty Meter telescopes are designed to work together to create capabilities far greater than the sum of their parts. They are complementary ground stations. The GMT would have an expansive view of the southern hemisphere heavens, and the TMT would do the same for the northern hemisphere.

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The goal is “all-sky” observation, a wide-angle view into deep space. Europe’s Extremely Large Telescope won’t have that capability. Besides boosting America’s competitive edge in astronomy, the powerful dual telescopes, with full coverage of both hemispheres, would allow researchers to gain a better understanding of phenomena that come and go quickly, such as colliding black holes and the massive stellar explosions known as supernovas. They would put us on a path to explore Earth-like planets orbiting other suns and address the question: “Are we alone?

Funding both the GMT and TMT is an investment in basic science research, the kind of fundamental work that typically has led to economic growth and innovation in our uniquely American ecosystem of scientists, investors and entrepreneurs.

Elon Musk’s SpaceX is the most recent example, but the synergy goes back decades. Basic science at the vaunted Bell Labs, in part supported by taxpayer contributions, was responsible for the transistor, the discovery of cosmic microwave background and establishing the basis of modern quantum computing. The internet, in large part, started as a military communications project during the Cold War.

Beyond its economic ripple effect, basic research in space and about the cosmos has played an outsized role in the imagination of Americans. In the 1960s, Dutch-born American astronomer Maarten Schmidt was the first scientist to identify a quasar, a star-like object that emits radio waves, a discovery that supported a new understanding of the creation of the universe: the Big Bang. The first picture of a black hole, seen with the Event Horizon Telescope, was front-page news in 2019.

We understand that competing in astronomy has only gotten more expensive, and there’s a need to concentrate on a limited number of critical projects. But what could get lost in the shuffle are the kind of ambitious projects that have made America the scientific envy of the world, inspiring new generations of researchers and attracting the best minds in math and science to our colleges and universities.

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Do we really want to pay that price?

Eric D. Isaacs is the president of Carnegie Science, prime backer of the Giant Magellan Telescope. Thomas F. Rosenbaum is president of Caltech, key developer of the Thirty Meter Telescope.

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Mosquito season is upon us. So why are Southern California officials releasing more of them?

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Mosquito season is upon us. So why are Southern California officials releasing more of them?

Jennifer Castellon shook, tapped and blew on a box to shoo out more than 1,000 mosquitoes in a quiet, upscale Inland Empire neighborhood.

The insects had a job to do, and the pest scientist wanted every last one out.

Aggressive and impactful reporting on climate change, the environment, health and science.

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Their task? Find lady mosquitoes and mate.

But these were no ordinary mosquitoes. Technicians had zapped the insects, all males, with radiation in a nearby lab to make them sterile. If they achieve their amorous quest, there will be fewer baby mosquitoes than there would be if nature ran its course. That means fewer mouths to feed — mouths that thirst for human blood.

“I believe, fingers crossed, that we can drop the population size,” said Solomon Birhanie, scientific director for the West Valley Mosquito and Vector Control District, which released the mosquitoes in several San Bernardino County neighborhoods this month.

Sterilized male mosquitoes flying out of a box in Rancho Cucamonga

Sterilized male Aedes mosquitoes are released from a box in Rancho Cucamonga.

(Myung J. Chun / Los Angeles Times)

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Controlling mosquitoes with mosquitoes

Mosquito control agencies in Southern California are desperate to tamp down an invasive mosquito — called Aedes aegypti — that has exploded in recent years. Itchy, unhappy residents are demanding it. And the mosquitoes known for fierce ankle biting aren’t just putting a damper on outdoor hangouts — they also spread disease.

The low-flying, day-biting mosquitoes can lay eggs in tiny water sources. A bottle cap is fair game. And they might lay a few, say, in a plant tray and others, perhaps, in a drain. Tackling the invaders isn’t easy when it can be hard to even locate all the reproduction spots. So public health agencies increasingly are trying to use the insects’ own biology against them by releasing sterilized males.

The West Valley district, which covers six cities in San Bernardino County, rolled out the first program of this kind in California last year. Now they’re expanding it. Next month, a vector district covering a large swath of Los Angeles County will launch its own pilot, followed by Orange County in the near future. Other districts are considering using the sterile insect technique, as the method is known, or watching early adopters closely.

On the plus side, it’s an approach that doesn’t rely on pesticides, which mosquitoes become resistant to, but it requires significant resources and triggers conspiracy theories.

“People are complaining that they can’t go into their backyard or barbecue in the summer,” Birhanie said at his Ontario lab. “So we needed something to strengthen our Aedes control.” Of particular concern is the Aedes aegypti, which love to bite people — often multiple times in rapid succession.

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Releasing sterilized male insects to combat pests is a proven scientific technique, but using it to control invasive mosquitoes is relatively new.

Vector control experts often point to the success of a decades-long effort in California to fight Mediterranean fruit flies by dropping enormous quantities of sterile males from small planes. That program, run by the U.S. Department of Agriculture and the California Department of Food and Agriculture, costs about $16 million a year. That’s nearly four times West Valley’s annual budget.

So rather than try to tackle every nook and cranny of the district, encompassing roughly 650,000 residents, West Valley decided to use a more targeted approach. If a problem area reaches a certain threshold — over 50 mosquitoes counted in an overnight trap — it becomes a candidate.

1 A man in a lab coat looks at plastic containers of mosquito larvae in a lab.

2 A man in a lab coat with a gloved hand uses an eye dropper in a plastic container with water and mosquito larvae.

3 Mosquito eggs in a lab

4 In the eye-dropper tube, water and mosquito larvae

5 A man in a lab coat demonstrates an X-ray machine that sterilizes the male mosquitoes.

1. Solomon Birhanie inspects a container of mosquito larvae in the lab at the West Valley Mosquito and Vector Control District in Ontario. 2. Birhanie and his team raise mosquitoes in the lab, separating them by sex, because only the males, which don’t bite humans, will eventually be released. 3. Mosquito eggs in the West Valley lab. 4. The lab can grow about 10,000 mosquitoes at a time. 5. Before the male mosquitoes are released, an X-ray machine sterilizes them. If the zapped males mate with a female, her eggs won’t hatch. (Allen J. Schaben / Los Angeles Times)

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And it’s still a big lift. About 10,000 mosquitoes are reared at a time at West Valley’s facility, about half of which will be males. The males are separated out, packed into cups and placed into an X-ray machine that looks like a small refrigerator. The sterilizing process isn’t that different from microwaving a frozen dinner. Zap them on a particular setting for four to five minutes and they’re good to go.

Equipment purchased for the program costs roughly $200,000, said Brian Reisinger, spokesperson for the district. He said it was too early to pin down a cost estimate for the program, which is expanding.

Some districts serving more people are going bigger.

The Greater Los Angeles County Vector Control District plans to unleash up to 60,000 mosquitoes a week in two neighborhoods in Sunland-Tujunga from mid-May through November.

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With the sterile-insect program, “the biggest hurdle we’re up against really is scalability,” said Susanne Kluh, general manager of the L.A. County district, which is responsible for nearly 6 million residents across 36 cities.

In part to save money, Kluh’s district has partnered with the Orange County Mosquito and Vector Control District. They’re sharing equipment and collaborating on studies, but L.A. County’s releases will move forward first, said Brian Brannon, spokesperson for the O.C. district. Orange County expects to release its “ankle biter fighters,” as Brannon called them, in Mission Viejo this fall or next spring.

So far, the L.A. County district has shelled out about $255,000 for its pilot, while O.C. has spent around $160,000. It’s a relatively small portion of their annual budgets: L.A. at nearly $25 million and O.C. at $17 million. But the area they’re targeting is modest.

Mosquito control experts tout sterilization for being environmentally friendly because it doesn’t involve spraying chemicals, and it may have a longer-lasting effectiveness than pesticides. It can also be done now. Other methods involving genetically modified mosquitoes and ones infected with bacteria are stuck in an approval process that spans federal and state agencies. One technique, involving the bacteria Wolbachia was recently approved by the Environmental Protection Agency and is now heading to the California Department of Pesticide Regulation to review, said Jeremy Wittie, general manager for the Coachella Valley Mosquito and Vector Control District.

“Using pesticides or insecticides, resistance crops up very quickly,” said Nathan Grubaugh, associate professor of epidemiology at the Yale School of Public Health.

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Vector control experts hope the fact that the sterilization technique doesn’t involve genetic modification will tamp down conspiracy theories that have cropped up around mosquito releases. One erroneous claim is that a Bill Gates-backed effort to release mosquitoes was tied to malaria cases in Florida and Texas. Reputable outlets debunked the conspiracy theory, pointing out that Gates’ foundation didn’t fund the Florida project and that the type of mosquito released (Aedes) does not transmit malaria.

To get ahead of concerns, districts carrying out the releases say they’ve engaged in extensive outreach and education campaigns. Residents’ desire to rid themselves of a scourge may overcome any anxieties.

“I think if you have the choice of getting eaten alive by ankle biters or having a DayGlo male X-rayed mosquito come by looking for a female to not have babies with, you’d probably go for the latter,” Brannon said. (“DayGlo” is a riff on the fluorescent pigment product of the same name — the sterilized mosquitoes were dusted with bright colors to help identify them.)

Mosquitoes buzz around the face of a woman wearing sunglasses

Sterilized male mosquitoes buzz around vector ecologist Jennifer Castellon as they are released in Rancho Cucamonga earlier this month.

(Myung J. Chun / Los Angeles Times)

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Disease at our doorstep

As the climate warms and some regions become wetter, dengue is expanding to areas it’s never been seen before — and surging in areas where it’s established. Florida has seen alarming spikes in the viral infection in recent years, and Brazil and Puerto Rico are currently battling severe outbreaks. While most people infected with dengue have no symptoms, it can cause severe body aches and fever and, in rare cases, death. Its alias, “breakbone fever,” provides a grim glimpse into what it can feel like.

In October of last year, the city of Pasadena announced the Golden State’s first documented locally transmitted case of dengue, describing it as “extremely rare” in a news release. That same month, a second case was confirmed in Long Beach. Local transmission means the patient hadn’t traveled to a region where dengue is common; they may have been bitten by a mosquito carrying the disease in their own neighborhood.

Surging dengue abroad means there’s more opportunity for travelers to bring it home. However, Grubaugh said it doesn’t seem that California is imminently poised for a “Florida-like situation,” where there were nearly 1,000 cases in 2022, including 60 that were locally acquired. Southern California in particular lacks heavy rainfall that mosquitoes like, he said. But some vector experts believe more locally acquired cases are inevitable.

A woman stands under a tree in a residential area, releasing mosquitoes from a box.

Ale Macias releases sterilized male mosquitoes in Upland this month.

(Myung J. Chun / Los Angeles Times)

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Set them free

In mid-April, a caravan of staffers from the West Valley district traveled to five mosquito “hot spots” in Chino, Upland and Rancho Cucamonga — where data showed mosquito levels were particularly high — to release their first batches of sterilized male mosquitoes for the year. Peak Aedes season is months away, typically August to October in the district, and Birhanie said that’s the point. The goal is to force down the numbers to prevent an itchy tsunami later.

Males don’t bite, so the releases won’t lead to more inflamed welts. But residents might notice more insects in the air. Sterilized males released by West Valley will outnumber females in the wild by at least 100 to 1 to increase their chances of beating out unaltered males, spokeperson Reisinger said.

“They’re not going to be contributing to the biting pressure; they’re just going to be looking for love,” as Reisinger put it.

Eggs produced by a female after a romp with a sterile male don’t hatch. And female mosquitoes typically mate only once, meaning all her eggs are spoiled, so to speak. Vector experts say the process drives down the population over time.

Interestingly, the hot spots were fairly spread out across the district, indicative of the bloodsuckers’ widespread presence and adaptive nature. A picturesque foothills community in Upland was “especially interesting” because of its relatively high elevation, Birhanie said.

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It was once inhabited primarily by another invasive mosquito that prefers colder, mountainous climates. Construction and deforestation in the area has literally paved the way for its humidity- and heat-loving brethren to move in.

Another neighborhood, in Rancho Cucamonga, posed a mystery. For the last two years, mosquito levels were consistently high. Door-to-door inspections, confoundingly, didn’t reveal the source.

“That’s one of the things about invasive Aedes mosquitoes — you can’t find them,” he said.

Next steps

Some vector control experts want to see a regional approach to sterile mosquito releases, similar to the state Medfly program.

Jason Farned, district manager for the San Gabriel Valley Mosquito and Vector Control District, believes a widespread effort “would be much more effective” and thinks that will come in time.

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There are no talks underway to make it happen, and it’s not yet clear how it would work. Vector control agencies are set up to serve their local communities.

Fears of a bad mosquito year ahead are bubbling as the weather warms. Rain — which there was plenty of this spring — can quickly transform into real estate for mosquito reproduction.

When the swarms come, mosquito haters can take typical precautions: dump standing water and wear repellent. And they can root for the sterile males to get lucky.

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After months of silence, Voyager 1 has returned NASA's calls

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After months of silence, Voyager 1 has returned NASA's calls

For the last five months, it seemed very possible that a 46-year-old conversation had finally reached its end.

Since its launch from Kennedy Space Center on Sept. 5, 1977, NASA’s Voyager 1 spacecraft has diligently sent regular updates to Earth on the health of its systems and data collected from its onboard instruments.

But in November, the craft went quiet.

Voyager 1 is now some 15 billion miles away from Earth. Somewhere in the cold interstellar space between our sun and the closest stars, its flight data system stopped communicating with the part of the probe that allows it to send signals back to Earth. Engineers at the Jet Propulsion Laboratory in La Cañada Flintridge could tell that Voyager 1 was getting its messages, but nothing was coming back.

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“We’re to the point where the hardware is starting to age,” said Linda Spilker, the project scientist for Voyager mission. “It’s like working on an antique car, from 15 billion miles away.”

Week after week, engineers sent troubleshooting commands to the spacecraft, each time patiently waiting the 45 hours it takes to get a response here on Earth — 22.5 hours traveling at the speed of light to reach the probe, and 22.5 hours back.

By March, the team had figured out that a memory chip that stored some of the flight data system’s software code had failed, turning the craft’s outgoing communications into gibberish.

A long-distance repair wasn’t possible. There wasn’t enough space anywhere in the system to shift the code in its entirety. So after manually reviewing the code line by line, engineers broke it up and tucked the pieces into the available slots of memory.

They sent a command to Voyager on Thursday. In the early morning hours Saturday, the team gathered around a conference table at JPL: laptops open, coffee and boxes of doughnuts in reach.

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At 6:41 a.m., data from the craft showed up on their screens. The fix had worked.

“We went from very quiet and just waiting patiently to cheers and high-fives and big smiles and sighs of relief,” Spilker said. “I’m very happy to once again have a meaningful conversation with Voyager 1.”

Voyager 1 is one of two identical space probes. Voyager 2, launched two weeks before Voyager 1, is now about 13 billion miles from Earth, the two crafts’ trajectories having diverged somewhere around Saturn. (Voyager 2 continued its weekly communications uninterrupted during Voyager 1’s outage.)

They are the farthest-flung human-made objects in the universe, having traveled farther from their home planet than anything else this species has built. The task of keeping communications going grows harder with each passing day. Every 24 hours, Voyager 1 travels 912,000 miles farther away from us. As that distance grows, the signal becomes slower and weaker.

When the probe visited Jupiter in 1979, it was sending back data at a rate of 115.2 kilobits per second, Spilker said. Today, 45 years and more than 14 billion miles later, data comes back at a rate of 40 bits per second.

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The team is cautiously optimistic that the probes will stay in contact for three more years, long enough to celebrate the mission’s 50th anniversary in 2027, Spilker said. They could conceivably last until the 2030s.

The conversation can’t last forever. Microscopic bits of silica keep clogging up the thrusters that keep the probes’ antennas pointed toward Earth, which could end communications. The power is running low. Eventually, the day will come when both Voyagers stop transmitting data to Earth, and the first part of their mission ends.

But on the day each craft goes quiet, they begin a new era, one that could potentially last far longer. Each probe is equipped with a metallic album cover containing a Golden Record, a gold-plated copper disk inscribed with sounds and images meant to describe the species that built the Voyagers and the planet they came from.

Erosion in space is negligible; the images could be readable for another billion years or more. Should any other intelligent life form encounter one of the Voyager probes and have a means of retrieving the data from the record, they will at the very least have a chance to figure out who sent them — even if our species is by that time long gone.

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