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Scent dogs detect coronavirus reliably from skin swabs

A recent study by the University of Helsinki and Helsinki University Hospital confirmed that scent detection dogs can be taught to identify individuals…

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A recent study by the University of Helsinki and Helsinki University Hospital confirmed that scent detection dogs can be taught to identify individuals with a coronavirus infection from skin swabs. In the experimental set-up at Finland’s Helsinki-Vantaa International Airport , the accuracy of the dogs in identifying the samples was 92 percent.

Credit: Egil Björkman

A recent study by the University of Helsinki and Helsinki University Hospital confirmed that scent detection dogs can be taught to identify individuals with a coronavirus infection from skin swabs. In the experimental set-up at Finland’s Helsinki-Vantaa International Airport , the accuracy of the dogs in identifying the samples was 92 percent.

The rapid and accurate identification and isolation of patients with coronavirus infection is an important part of global pandemic management. The current diagnosis of coronavirus infection is based on a PCR test that accurately and sensitively identifies coronavirus from other pathogens. However, PCR tests are ill-suited for screening large masses of people because of, among other things, their slow results and high cost.

Researchers from the Faculties of Veterinary Medicine and Medicine at the University of Helsinki and from Helsinki University Hospital jointly designed a triple-blind, randomized, controlled study set-up to test the accuracy of trained scent detection dogs where none of the trio – dog, dog handler or researcher – knew which of the sniffed skin swab samples were positive and which negative. The study also analysed factors potentially interfering with the ability of the dogs to recognize a positive sample.

The three-faceted study has now been published in the journal BMJ Global Health. The study provides valuable information on the use of scent dogs in pandemic control.

Correct identification in over 90 percent of samples; only small differences in accuracy between dogs

In the first phase of the study, the dogs were taught to discriminate the skin swab samples of coronavirus patients from those of volunteers who tested negative. After a training period of several weeks, the dogs moved from the training centre to Helsinki-Vantaa Airport for the next stages of the study.

In the second phase of the study, four trained dogs completed a validation test to prove their discriminatory ability. During the experiment, each dog was presented with a series of 420 samples over a period of seven days. As several parallel samples had been collected from each sample donor, each dog received an identical set of 114 coronavirus patient samples and 306 control samples for sniffing. The coronavirus status of all sample donors had been confirmed by PCR. During each testing day, the dog sniffed 20 sample tracks with three samples each, with the tracks presented in random order.

The dogs recognized the samples correctly 92 percent of the time. While their sensitivity to detect a positive coronavirus sample was 92 percent, their specificity was 91 percent. Only small differences in accuracy were observed between the four dogs. The coronavirus infection being caused by virus variants was the single largest factor contributing to erroneous identification by the dogs.

The study confirms previous reports suggesting that scent dogs can identify individuals with a coronavirus infection.

“Our study set-up was of a high scientific standard. The sample sizes were sufficiently large, and all dogs sniffed an identical set of samples, allowing comparison of their performances. The dogs also had to successfully indicate sample sets containing only negative samples – an important trait when screening individuals. Another significant advantage was that samples were collected from outpatients instead of hospital patients. In addition, the testing was performed under real-life conditions rather than in a laboratory”, says the leader of the DogRisk research group and docent of clinical research in companion animals Anna Hielm-Björkman from the University of Helsinki.

“I was particularly impressed by the fact that dogs performed worse with samples we had collected from patients suffering from a disease caused by a coronavirus variant. The explanation is simple: the dogs had originally been trained with the initial wild-type virus, and thus they did not always identify the variant samples as positive. This reveals their incredible ability of discrimination”, says Anu Kantele, Professor of Infectious Diseases and Chief Physician at the University of Helsinki and Helsinki University Hospital.

Major help from scent dogs at airports and ports

The third phase of the study was conducted by screening passengers and staff at Helsinki-Vantaa Airport in a real-life situation. The scent dogs correctly identified 98.7 percent of the negative samples. The low number of coronavirus-positive samples in real-life testing prevented a proper assessment of the dogs’ performance with positive samples. However, based on positive ‘work motivation samples’ regularly given to the dogs during this part of the study, the performance on the correctly identified positive samples also was evaluated at 98.7 percent. Work motivation samples are naive samples pre-collected from PCR positive patients, but not previously sniffed by dogs. They are provided to the dogs at regular intervals to maintain their interest in the target odour in situations and environments where the proportion of positive samples is otherwise very low.

“Scent dogs can provide an invaluable tool for limiting viral spread during a pandemic, serving for example at air- and seaports. Such a reliable, cheap approach to rapidly screen a vast number of samples or to identify passing virus carriers from a large crowd is of value particularly when the testing capacity with traditional approaches is insufficient”, says Anu Kantele.

“Our research group will continue to study how scent dogs can best help our society. We hope that this newly published study will help to allocate funds for the development of this new ‘tool’. There are many other diseases where research could benefit from the excellent sense of smell that these dogs possess”, says Hielm-Björkman.

The study was conducted with the support of the Finnish Cultural Foundation, Svenska Kulturfonden i Finland, Academy of Finland, Jane and Aatos Erkko Foundation, Finnish Medical Association, Veterinary Hospital Chain Evidensia, Nose Academy, Finavia, Vantaa city and deputy mayor Timo Aronkytö. The research group of Anna Hielm-Björkman has also been supported by private donations through the coronadog fundraising campaign, organized jointly by the Finnish Kennel Club and the University of Helsinki. The dogs were initially trained at the NGO Wise Nose trainings center.


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Cruise Line Drops Pre-Cruise Covid Testing Rule

The major cruise lines walk a delicate line. They need to take the actual steps required to keep their passengers safe and they also need to be aware of…

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The major cruise lines walk a delicate line. They need to take the actual steps required to keep their passengers safe and they also need to be aware of how things look to the outside public. It's a mix of practical covid policy balanced with covid theater.

You have to do the right thing -- and Royal Caribbean International (RCL) - Get Royal Caribbean Group Report, Carnival Cruise Lines (CCL) - Get Carnival Corporation Report, and Norwegian Cruise Lines (NCLH) - Get Norwegian Cruise Line Holdings Ltd. Report have been doing that with very meticulous protocols-- but you also have to show the general public you're taking the pandemic seriously. The cruise industry has been under the microscope of both public perception and the Centers for Disease Control (CDC) since covid first appeared.

That's not because you're likely to get infected on a cruise ship than at a concert, sporting event, theme park, restaurant, or any other crowded space. It's because when you get sick at one of those locations nobody can pinpoint the source of your infection

Cruises last from 3 days to 7 days or even longer and that means that some people will get covid onboard and that will be blamed on the cruise industry. To mitigate that Carnival, Royal Caribbean, and Norwegian have rigid protocols in place that require passengers 12 and over to be vaccinated as well as pre-cruise covid tests taken no more than two days before your cruise leaves.

Once cruise line has dropped that testing requirement (at least on a few sailings) and that could lead Royal Caribbean, Carnival, and Norwegian to follow. 

Sina Schuldt/picture alliance via Getty

Holland America Drops Some Covid Testing

As the largest cruise lines sailing from the U.S., Royal Caribbean, Carnival, and Norwegian don't want to be the first to make major covid policy changes. They acted more or less in tandem when it came to loosening, then dropping mask rules and have generally followed the lead of the CDC, even when that agency's rules became optional.

Now, Holland America cruise line has dropped pre-cruise covid testing on a handful of cruises. It's a minor move, but it does provide cover and precedent for Royal Caribbean, Carnival, and Norwegian to eventually do the same.

"Holland America Line becomes the first US-based cruise line to remove testing for select cruises. Unfortunately for those taking a cruise from the United States, the new protocols are only in place for certain cruises onboard the company’s latest ship, the Rotterdam, in Europe," Cruisehive reported.

The current CDC guidelines do recommend pre-cruise testing, but the cruise lines into following those rules. By picking cruises sailing out of Europe, Holland America avoids picking a fight with the federal agency just yet, but it will be able to gather data as to whether the pre-cruise testing actually helps.

Holland America has not changed its vaccination requirements for those cruises which mirror the 12-and-up rule used by Royal Caribbean, Carnival, and Norwegian.

Some guests have called for the end of the testing requirement because they believe it's more theater than precaution because people can test and then contract covid while traveling to their cruise.

The Current Cruise Protocols Work

Royal Caribbean President Michael Bayley does expect changes to come in his cruise line's covid protocols, and he talked about them during Royal Caribbean's recent President's Cruise, the Royal Caribbean Blog reported.

"I think pre cruise testing is going to be around for another couple of months," Bayley told passengers during a question and answer session. "We obviously want it to go back to normal, but we're incredibly cognizant of our responsibilities to keep our crew, the communities and our guests safe."

People do still get covid onboard despite the crew being 100% vaccinated and all passengers 12 and over being vaccinated, but the protocols have worked well when it comes to preventing serious illness.

Bayley said that the CDC shared some information with him in a call.

"The cruise industry sailing out of the US ports over the past 12 months and how many people have been hospitalized with Covid and how many deaths occurred from Covid from people who'd sailed on the industry's ships, which is in the millions," he said, "And the number of people who died from COVID who'd sailed on ships over the past year was two."

That success may be why the major cruise lines are reluctant to make changes. The current rules, even if they're partially for show, have been incredibly effective.

"Two is terrible. But but but against the context of everything we've seen, that's it's truly been a remarkable success." he added.

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Visualizing A Decade Of Population Growth And Decline In US Counties

Visualizing A Decade Of Population Growth And Decline In US Counties

There are a number of factors that determine how much a region’s population…

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Visualizing A Decade Of Population Growth And Decline In US Counties

There are a number of factors that determine how much a region’s population changes.

If an area sees a high number of migrants, along with a strong birth rate and low death rate, then its population is bound to increase over time. On the flip side, as Visual Capitalists Nick Routley details below, if more people are leaving the area than coming in, and the region’s birth rate is low, then its population will likely decline.

Which areas in the United States are seeing the most growth, and which places are seeing their populations dwindle?

This map, using data from the U.S. Census Bureau, shows a decade of population movement across U.S. counties, painting a detailed picture of U.S. population growth between 2010 and 2020.

Counties With The Biggest Population Growth from 2010-2020

To calculate population estimates for each county, the U.S. Census Bureau does the following calculations:

      A county’s base population → plus births → minus deaths → plus migration = new population estimate

From 2010 to 2020, Maricopa County in Arizona saw the highest increase in its population estimate. Over a decade, the county gained 753,898 residents. Below are the counties that saw the biggest increases in population:

Phoenix and surrounding areas grew faster than any other major city in the country. The region’s sunny climate and amenities are popular with retirees, but another draw is housing affordability. Families from more expensive markets—California in particular—are moving to the city in droves. This is a trend that spilled over into the pandemic era as more people moved into remote and hybrid work situations.

Texas counties saw a lot of growth as well, with five of the top 10 gainers located in the state of Texas. A big draw for Texas is its relatively affordable housing market. In 2021, average home prices in the state stood at $172,500$53,310 below the national average.

Counties With The Biggest Population Drops from 2010-2020

On the opposite end of the spectrum, here’s a look at the top 10 counties that saw the biggest declines in their populations over the decade:

The largest drops happened in counties along the Great Lakes, including Cook County (which includes the city of Chicago) and Wayne County (which includes the city of Detroit).

For many of these counties, particularly those in America’s “Rust Belt”, population drops over this period were a continuation of decades-long trends. Wayne County is an extreme example of this trend. From 1970 to 2020, the area lost one-third of its population.

U.S. Population Growth in Percentage Terms (2010-2020)

While the map above is great at showing where the greatest number of Americans migrated, it downplays big changes in counties with smaller populations.

For example, McKenzie County in North Dakota, with a 2020 population of just 15,242, was the fastest-growing U.S. county over the past decade. The county’s 138% increase was driven primarily by the Bakken oil boom in the area. High-growth counties in Texas also grew as new sources of energy were extracted in rural areas.

The nation’s counties are evenly divided between population increase and decline, and clear patterns emerge.

Pandemic Population Changes

More recent population changes reflect longer-term trends. During the COVID-19 pandemic, many of the counties that saw the strongest population increases were located in high-growth states like Florida and Texas.

Below are the 20 counties that grew the most from 2020 to 2021.

Many of these counties are located next to large cities, reflecting a shift to the suburbs and larger living spaces. However, as COVID-19 restrictions ease, and the pandemic housing boom tapers off due to rising interest rates, it remains to be seen whether the suburban shift will continue, or if people begin to migrate back to city centers.

Tyler Durden Sat, 07/02/2022 - 21:00

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Tesla EV deliveries fall nearly 18% in second quarter following China factory shutdown

Tesla delivered 254,695 electric vehicles globally in the second quarter, a nearly 18% drop from the previous period as supply chain constraints, China’s…

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Tesla delivered 254,695 electric vehicles globally in the second quarter, a nearly 18% drop from the previous period as supply chain constraints, China’s extended COVID-19 lockdown and challenges around opening factories in Berlin and Austin took their toll on the company.

This is the first time in two years that Tesla deliveries, which were 310,048 in the first period this year, have fallen quarter over quarter. Tesla deliveries were up 26.5% from the second quarter last year.

The quarter-over-quarter reduction is in line with a broader supply chain problem in the industry. It also illustrates the importance of Tesla’s Shanghai factory to its business. Tesla shuttered its Shanghai factory multiple times in March due to rising COVID-19 cases that prompted a government shutdown.

Image Credits: Tesla/screenshot

The company said Saturday it produced 258,580 EVs, a 15% reduction from the previous quarter when it made 305,407 vehicles.

Like in other quarters over the past two years, most of the produced and delivered vehicles were Model 3 and Model Ys. Only 16,411 of the produced vehicles were the older Model S and Model X vehicles.

Tesla said in its released that June 2022 was the highest vehicle production month in Tesla’s history. Despite that milestone, the EV maker as well as other companies in the industry, have struggled to keep apace with demand as supply chain problems persist.

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