Dogs can detect coronavirus in people; Immune system can cause broad damage in COVID-19

The following is a roundup of some of the latest scientific studies on the novel coronavirus and efforts to find treatments and vaccines for coronavirus disease 2019 (COVID-19), the illness caused by the virus.

Dogs can sniff out COVID-19

Trained dogs can identify people with COVID-19, even those with no symptoms, according to researchers.

In the preliminary study published on Thursday in PLoS One, dogs who sniffed swab samples of armpit sweat could tell which samples came from COVID-19 patients and which were from people who tested negative for the new coronavirus.

That study was conducted in March. More recently, the researchers have validated the findings in additional trials, said study leader Dominique Grandjean of Alfort Veterinary School in France.

Dogs can identify infected individuals with 85% to 100% accuracy and rule out infection with 92% to 99% accuracy, Grandjean said. "It takes one tenth of a second for a trained dog to say 'yes' or 'no'," he said.

Training requires 3 to 8 weeks depending on whether the dog is already trained for odor detection. COVID-19-detecting dogs have already been deployed in airports in the United Arab Emirates, Grandjean said.

On Wednesday, the UAE and the International K9 Working Group Against COVID-19 will host a virtual workshop on the use of these trained dogs, with 25 countries expected to participate, according to the organizers.

Immune system can self-attack broadly in COVID-19

Antibodies are supposed to attack invading germs, but severely ill COVID-19 patients have so-called autoantibodies that mistakenly attack not just their own tissues and organs but even virus-fighting proteins produced by the immune system, new research shows.

Scientists studied 194 COVID-19 patients, including 55 with severe disease, plus a control group of 30 people without the virus.

In the sickest patients, they found a high frequency of autoantibodies created by the immune system causing injury to the central nervous system, blood vessels, and connective tissues like cartilage, ligaments and tendons.

They also found a high prevalence of autoantibodies that interfere with substances involved in the functioning of the immune system itself, including cytokines and other "immunomodulatory" proteins.

"The surprising extent of autoantibody reactivities" in these patients indicates that these mistakenly targeted antibodies are "an intrinsic aspect" of COVID-19. The report was posted on medRxiv on Saturday ahead of peer review. -- Reuters