Study finds Chandler man gave pets COVID-19 - SanTan Sun News SanTan Sun News

Study finds Chandler man gave pets COVID-19

November 8th, 2021 development
Study finds Chandler man gave pets COVID-19

Santan Sun News Staff

Scientists say a Chandler resident is the world’s first genetically documented case of COVID-19 transmission from a human to an animal.

The Translational Genomics Research Institute (TGen), an affiliate of City of Hope, last week announced that it has published its findings from an ongoing study in the journal “One Health.”

While there are five pilot studies nationwide examining COVID in animals, the TGen study is the only one to include genomic sequencing of the virus from both pet and human samples.

“This level of testing resulted from TGen’s overall efforts to monitor the virus and its potentially more-dangerous variants by sequencing as many positive human samples of the virus as possible,” TGen senior science writer Steve Yozwiak said.

Hayley Yaglom, a TGen epidemiologist at the institute’s infectious-disease lab in Flagstaff and lead author of the study, said the Chandler case is “the first example we had from the project that demonstrated the likelihood of virus transmission from a pet owner to animals in the household.”

“This is a great example of using genomics to gain intelligence about pathogens,” said David Engelthaler, Ph.D., director of TGen’s Pathogen and Microbiome Division, the branch of TGen studying infectious diseases. “This study shows that we can not only use genomics to help track COVID variants across the globe, but we can also use this technology to track exact transmissions, and in this case transmission from pet owners to pets.”

Patient confidentiality prevents TGen from saying much about man at the center of the study’s discovery, except to say that the “pet parent” infected his dog and cat.

“The pet parent was not yet vaccinated, took little precaution to protect his cat and dog and entertained guests who were not vaccinated. The owner recovered from COVID, and both his pets were asymptomatic,” Yozwiak said.

The animals were confined to an apartment and “had little-to-no opportunity to be exposed to the virus and so it was highly unlikely that the pets infected their owner,” he added.

“Plus, in each case examined in the study, it was the pet parent who exhibited COVID first,” Yozwiak said. “Worldwide, there is no documented case of COVID transmission from a pet to its pet parent.”

Researchers were unable to tell if the dog or cat were infected first, or if one infected the other, “though that is a possibility,” he added.

The Chandler dog and cat “were buddies who had close contact with each other,” researchers said.

TGen’s infectious-disease laboratory is located in Flagstaff, and is its base for all its anti-COVID research.

In this study, Yaglom and a veterinarian from the Arizona Department of Health Services visited the homes in Coconino and Maricopa counties of pet owners who have tested positive for the virus in the past two weeks and test their pets for COVID.

Arizona researchers tested 39 dogs and 22 cats in 24 households and found 14 positive cases of COVID in pets among six households.

TGen’s COVID animal study is conducted under a grant from the Arizona Department of Health Services. Funds come from the U.S. Centers for Disease Control and Prevention in coordination with the Council of State and Territorial Epidemiologists.

The Chandler man and his pets “all were infected with the identical strain of coronavirus: B.1.575, an early and unremarkable version” of the COVID-cuasing virus, Yozwiak said.

“Fewer than 25 documented cases exist of Arizonans infected with this strain, according to information drawn from the COVID variant tracking dashboard that TGen maintains for the CDC and ADHS,” Yozwiak added.

To date, more than 46,000 positive samples of Arizonans with COVID have been genetically sequenced, he said.

Researchers deduced that the virus spread from the pet parent to either the dog or cat, or both.

Yaglom said the findings reinforced the need for pet owners to protect their pets by getting vaccinated.

If they do get COVID, they should wear masks when they are around their pets. “As difficult as it might be for many pet owners, they should avoid cuddling, kissing, allowing pets to lick their faces, or sleeping with them,” Yozwiak added.

Owners don’t have to completely isolate from their pets, Yaglom said, but they should minimize contact “as best they can” while they exhibit COVID symptoms.

The study will continue through the rest of 2021 and might go into 2022 if researchers obtain additional funding, which would allow them to continue education and outreach efforts, bolstering active surveillance of the virus.

Dog and cat owners who have tested positive for COVID-19 within the past two weeks are eligible to participate in the study. The tests are free. Owners must be at least 18, provide consent and fill out a questionnaire. The pet must be vaccinated against rabies, mainly housed indoors, and tolerant of the handling and restraint necessary for routine veterinary care.

A veterinarian is present when samples are taken. No animals are harmed in the course of this study.

Pet owners must wear masks during sample collection, and project staff will wear masks and gloves. Spanish-speaking staff will be available, as needed. Pet owners will be notified of test results within 3-4 weeks. For pets that test positive, owners may be asked to enable collection of additional samples. Positive tests will be reported to the Arizona State Veterinarian and ADHS.

For more information about testing pet dogs or cats for COVID, or to participate in the study,

TGen, an affiliate of City of Hope, is a nonprofit organization dedicated to conducting groundbreaking research with life-changing results. The City of Hope is a world-renowned independent research and treatment center for cancer, diabetes and other life-threatening diseases.

Both institutes to complement each other in research and patient care, with City of Hope providing a clinical setting to advance scientific discoveries made by TGen. TGen is focused on helping patients with neurological disorders, cancer, diabetes and infectious diseases through cutting-edge translational research.

TGen physicians and scientists work to unravel the genetic components of both common and complex rare diseases in adults and children.


This is a great example of using genomics to gain intelligence about pathogens.

– David Engelthaler