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No more nose swabs? Why a saliva test for COVID-19 could be a 'game changer' – CBC.ca

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Instead of having an extra-long swab pushed way up your nose, you could soon just spit into a cup to get tested for COVID-19. 

SalivaDirect, a cheap, saliva-based test for the disease developed by researchers at Yale University, received emergency authorization for use from the U.S. Food and Drug Administration earlier this week. The test was developed with the help of funding from the NBA, National Basketball Players Association and a grant from the Mercatus Center at George Mason University.

Rather than being commercialized and licensed to particular companies, it’s being released as an “open source” protocol — a recipe that’s freely available for other labs to follow using a variety of commercially available ingredients and equipment. 

Unfortunately, the test isn’t yet available in Canada. But here’s why the new test and similar tests under development could be a big step forward in keeping the pandemic under control.

The team says the new saliva-based test is ‘simpler and less invasive’ than traditional nasopharyngeal swab tests for COVID-19. (Lisa Maree Williams/Getty Images)

How the SalivaDirect test works

The test detects genetic material or RNA from SARS-CoV-2, the coronavirus that causes COVID-19, using equipment in a lab.

In that way, it’s very similar to the nose swab tests that have been the standard for detecting COVID-19 up until now. Because that analysis has to be done in a lab, the results aren’t instantaneous — like the traditional test, they’ll take about a day to come back.

But the new test has two main differences:

  • The RNA is collected from saliva, not a nose swab.
  • It skips a step required in standard tests called “nucleic acid extraction,” which separates RNA from the sample and requires special chemical ingredients. Instead, it uses a widely available enzyme and heat.

Lab tests comparing SalivaDirect to a traditional nasal swab test found it was only slightly less sensitive, and both types of tests got the same result more than 90 per cent of the time.

Swab samples are tested for coronavirus RNA at a hospital in Liege, Belgium. SalivaDirect also tests for RNA, so analysis in the new saliva-based test must also be done in a lab. (Francisco Seco/The Associated Press)

Main advantages

Even people who haven’t had the test probably aren’t enticed by images or video of the nose swabbing procedure.

“We can all agree that it’s not a pleasant experience,” said Anne Wyllie, associate research scientist at the Yale School of Public Health, part of the team that developed the new test.

The team calls the test “simpler and less invasive” than traditional nasopharyngeal swab tests for COVID-19.

But its advantages go beyond comfort.

In an FDA news release, Admiral Brett G. Giroir, assistant secretary at the U.S. Department of Health and Human Services and its COVID-19 testing co-ordinator, called the new test a “testing innovation game changer that will reduce the demand for scarce testing resources.”

That’s because:

  • The sample can be collected in any sterile container and requires neither nose swabs, which are sometimes in short supply, nor chemicals called nucleic acid preservatives.
  • Skipping the nucleic acid extraction step eliminates the need for the chemical kits and reagents, which are also sometimes in short supply. It also reduces the processing time.
  • The sample can be collected by the patient him or herself under supervision of a health-care worker. That could potentially lower the risk to health-care workers, who currently have to do the nose swabbing on patients.
  • It has already been tested and shown to work with reagents and instruments from different companies. “This flexibility enables continued testing if some vendors encounter supply chain issues, as experienced early in the pandemic,” Yale University said in a news release.
  • That also makes it cheaper than traditional COVID-19 testing, in addition to being simpler and less invasive. Wyllie estimates the chemical ingredients needed for the test cost less than $4 US ($5.30 Cdn), and she thinks labs could do it for roughly $10 a sample.
One U.S. company, DiaCarta, has already submitted its COVID-19 saliva test to Health Canada for review. Health Canada says it hasn’t been accepted yet, but the department is working ‘as quickly as possible.’ (CBC News)

Limited testing, availability so far

So far, the test has only undergone limited testing in the lab and results have only been published online, prior to peer review, on a few dozen known positive and negative samples.

“It’s really with a small, fairly controlled sample,” said Dr. Andrew Morris, a professor of medicine at the University of Toronto and Sinai Health System, who wasn’t involved in the research. “We don’t know how the test will perform in the real world.”

However, based on that preliminary data, he called the performance “pretty good.”

Spitting in a cup may soon be an alternative to the standard COVID-19 test that goes up through the nose, but saliva tests haven’t yet been approved for use in Canada. 2:00

SalivaDirect is currently being tested on the field in partnership with the National Basketball Association and the National Basketball Players Association. Part of the goal is to find out:

  • If it’s effective for detecting asymptomatic or presymptomatic cases.
  • If cases can be detected in “pooled” samples where samples from many individuals are combined for testing at the same time, to see if cases are popping up, for example, on a team or in a workplace.

The test will be offered first at the Yale Pathology Laboratory and at the Jackson Laboratory for Genomic Medicine in Farmington, Conn.

It has not yet been authorized for use in Canada. But Morris says in general, once tests are approved by Health Canada, provinces have been able to scale up pretty rapidly.

Morris notes that SalivaDirect isn’t the first saliva test for COVID-19 authorized in the U.S. — the FDA says it’s the fifth: “It just appears that this one is easier and doesn’t require the [extraction] reagents.”

A similar test from Rutgers Clinical Genomics Laboratory and Spectrum Solutions is being used by Major League Baseball.

One U.S. company, DiaCarta, has already submitted its COVID-19 saliva test to Health Canada for review. Health Canada says it hasn’t been accepted yet, but the department is working “as quickly as possible.”

Norm Powell, left, of the Toronto Raptors steals the ball from Garrett Temple of the Brooklyn Nets in Game 2 of an NBA playoff series, Wednesday. The saliva-based test was developed with funding from the NBA and the National Basketball Players Association. (Kevin C. Cox/Pool Photo/AP)

Potential applications: Schools, workplaces

However, Morris thinks it could lead to wider testing.

“It’s been difficult to get people to go to assessment centres,” he said. “If they’re able to provide a spit sample, it will make it a lot easier for public health officials to get samples from people we need to get it from.”

He thinks it has a lot of promise for large populations such as school, college or university students and large workplaces.

Future of saliva tests

Wyllie hopes the saliva test will also be a stepping stone toward faster tests and at-home tests.

Those would be similar to at-home pregnancy tests that provide results within minutes, allowing people to test daily before work or school.

Some such tests are already under development. In Canada, there are teams working on development at the University of Saskatchewan, the University of Regina and Ontario’s Western University; Kelowna, B.C.-based Metabolic Insights; and Victoria-based ImmunoPrecise Antibodies in collaboration with the University of Victoria.

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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