In-depth summary of reports of naturally acquired SARS-CoV-2 infections in domestic animals and farmed or captive wildlife

Updated June 2, 2020

This in-depth summary was prepared by AVMA staff and will be updated on a regular basis as new reports are published. Information is tabulated chronologically, with the most recent report first. General descriptions of the tests used are provided in the SARS-CoV-2 in animals section of the AVMA COVID-19 webcenter.

The World Organisation for Animal Health (OIE) indicates that "infection of animals with COVID-19 virus meets the criteria of an emerging disease. Therefore, any infection of animals with the COVID-19 virus...should be reported to the OIE in accordance with the Terrestrial Animal Health Code." The government of each Member State submits reports to the OIE. USDA-APHIS submits disease notification on behalf of the United States. Immediate notifications and follow-up reports are available via the OIE World Animal Health Information Database (WAHIS) Interface (search COVID-19).

 

RESULTS OF TESTS PERFORMED*
 
Event Start or Report Date
Country (State)**
Species (number)
RT-PCR
Virus Isolation
Neutralizing Antibody
Published on OIE-WAHIS
(dates of reports)

June 2, 2020

USA (New York)13

Dog (1)

Positive

Not reported

Not reported

NO (as of June 2)

May 21, 2020

Spain2

CAT (1)

Positive

Not reported

Not reported

NO

May 18, 2020

Russia12

CAT (1)

Positive

Not reported

Not reported

Yes (May 26)

May 15, 2020

The Netherlands10

DOG (1)

Negative

Not reported

Positive

NO

May 15, 2020

May 25, 2020

The Netherlands1

CATS (3; mink farms)

CATS (4; mink farms)

 Positive (1 cat only)

Not reported

Positive

(all 7 cats)

NO

May 13, 2020

Germany9

CAT (1)

Positive

Not reported

Not reported

NO; but OIE is aware

May 12, 2020

France3

CAT (1)

Positive

Not reported

Not reported

NO; but OIE is aware

May 8, 2020

The Netherlands1

MINK (multiple)

Positive

Not reported

Not reported

NO

May 8, 2020

Spain2

CAT (1)

Positive

Not reported

Not reported

NO; but OIE is aware

May 1, 2020

France3

CAT (1)

Positive

Not reported

Not reported

NO; but OIE is aware (scroll to Findings in Animals section)

Apr 28, 2020

May 27, 2020

USA (North Carolina)4

DOG (1)

Positive, but not confirmed by testing at NVSL

Negative on confirmatory testing at NVSL

Negative on confirmatory testing at NVSL

Results of confirmatory testing did not meet the USDA case definition for SARS-CoV-2; no report required

Apr 26, 2020

The Netherlands1

MINK (multiple)

Positive

Not reported

Not reported

NO; but OIE is aware

April 2, 2020

China11

CATS (3)

Not done

Not done

Positive

NO

Apr 1 & 6, 2020

USA (New York)5

CATS (2)

Positive

Not reported

Positive

YES (Apr 22 & 29)

Mar 30, 2020

Hong Kong6

CAT (1)

Positive

Negative

Positive

YES (Apr 3, May 4)

Mar 27, 2020

USA (New York/Bronx Zoo)7

TIGERS/LIONS (7)***

Positive

Not done

Not done

NO

Mar 27, 2020

USA (New York/Bronx Zoo)7

LION (1)

Positive

Not reported

Not reported

Yes (Apr 17)

Mar 27, 2020

USA (New York/Bronx Zoo)7

TIGER (1)

Positive

Not reported

Not reported

YES (Apr 6)

Mar 18, 2020

Belgium8

CAT (1)

Positive

Not reported

Not reported

NO; but OIE is aware

Mar 18, 2020

Hong Kong6

DOG (1)

Positive

Positive

Positive

YES (Mar 20 & Apr 7)

Feb 27, 2020

Hong Kong6

DOG (1)

Positive

Negative

Positive

YES (Feb 29, Mar 7, 16, & 28)

*Not reported means AVMA does not know whether test is in process with results to be determined or whether test was not done and will not likely be performed on this/these animals in the future. Not done means test was not performed when report submitted and is unlikely to be performed on this/these animals in the future.
**Superscript refers to summary text on the following pages and, specifically, to the section in which additional details are provided.
***8 large cats (5 tigers and 3 lions) were believed to be infected with SARS-CoV-2. The first positive tiger reported to the OIE on April 6 was not included in the fecal testing, but the first positive lion reported on April 17 was included. All 8 large cats are described together in Section 7 of the summary text on the following pages.

SECTION 1: FARMED MINK IN THE NETHERLANDS

On April 26, Reuters reported that several mink on each of two large farms in the Netherlands had tested positive for SARS-CoV-2. Further details were provided in a report from the Dutch Minister of Agriculture, Nature, and Food Quality to the Dutch Parliament. The first farm comprised two closely situated locations housing mink, whereas at the second farm all mink were housed in a single location. Each farm had noted an increased incidence of gastrointestinal and respiratory disease and overall mortality in their animals, and several ailing mink from each farm were euthanized and then necropsied. Samples were collected from multiple tissues and organs and sent to Wageningen Bioveterinary Research in Lelystad for assessment via a SARS-CoV-2-specific PCR assay. On April 24, 2020, results confirmed that SARS-CoV-2 RNA was detected in the affected mink.

Several animal caretakers at each farm had developed symptoms consistent with COVID-19, although they were not tested. It is believed these caretakers transmitted the virus to the mink. Plans were initiated to conduct additional testing of other mink, both sick and healthy, and air and dust samples from each farm for SARS-CoV-2. All Dutch mink farmers, veterinarians, and researchers were also notified of the new requirement to report any respiratory problems or increased mortality in mink. As an additional precautionary measure, the Dutch public health agency advised people against cycling or walking within a radius of approximately 400 meters around each infected farm until the results from tests on air and dust samples were known.

On May 8, the Minister reported that SARS-CoV-2 had been detected in mink from two additional farms in the same province as the first two farms (North Brabant), bringing the total of infected mink farms in The Netherlands to four. Human safety and health precautions put into place for the first two infected farms were implemented on the second set of infected farms. Ongoing studies of SARS-CoV-2 in mink will include samples from all four farms.

As of May 26, the Minister had provided four reports (May 8, May 15, May 19, May 25) to the Parliament describing results of studies done at the infected farms. Additional information is available on the English language area of the Dutch government web site, and a preprint of early results from the first two farms was also posted on May 18 at the bioRxiv site. Key findings outlined in the Minister’s reports and the bioRxiv preprint include:

  • The initial determination that the first two farms were infected was made on the basis of detection of SARS-CoV-2 RNA in lung samples collected on April 21 or April 25 from three mink that had recently died on the first or second farm, respectively. Viral specific RNA was detected by use of quantitative RT-PCR. (bioRxiv preprint).
  • SARS-CoV-2 infection in mink can lead to pneumonia and death, but morbidity and mortality rates are low. Pregnant animals appear to develop more serious disease and are more likely to die as a result; however, no increase in pup mortality was noticed (May 8 report & bioRxiv preprint).
  • During the week after initial detection of infected mink on each farm, 18 additional mink that had recently died were collected from each farm and necropsied. A throat and rectal swab were collected from each animal at necropsy for virus-specific quantitative RT-PCR analysis. Viral RNA was detected in all throat swabs and in 34 of the 36 rectal swabs. Viral loads were higher in the throat swabs, compared with the rectal swabs (bioRxiv preprint).
  • Mink can also be asymptomatically infected with SARS-CoV-2 (May 19 report).
  • The virus seemed to have been present on both of the first two infected farms for several weeks before initial detection of infected mink (May 8 report).
  • The difference in sequences between the viruses infecting mink on the two farms suggest that there was a different source of infection for the mink on each farm (May 8 report & bioRxiv preprint).
  • Mink on each farm were most likely initially infected via transmission of the virus from farm workers with COVID-19. However comparative analyses of viral sequences detected in samples from mink on the first two farms suggest subsequent transmission of virus amongst the mink on each farm (May 8 report & bioRxiv preprint).
  • Mink on each of the first two farms are caged separately with non-permeable partition between cages, precluding direct contact as a mode of transmission. Indirect transmission between minks could occur via fomites (e.g., feed or bedding material contaminated with virus from infected humans), infectious droplets generated by the infected mink, or contaminated dust from the fecally-contaminated bedding of infected mink (bioRxiv preprint).
  • Comparison of viral RNA sequences from SARS-CoV-2 isolated from humans in The Netherlands with those from the virus infecting mink on the first two farms initially indicated that mink-to-human transmission had not occurred (May 8 report). However, in the Minister’s reports on May 19 and May 25, and based on initial comparative analyses plus phylogenetic mapping of viral genomic sequences from infected mink with those from four infected farm workers, one working on the farm described in the May 19 report and three on the farm described in the May 25 report, it was suggested that mink-to-human transmission likely occurred.
  • Additional comparative sequence analyses and phylogenetic mapping results outlined in the May 25 report indicate that the genomic sequences of SARS-CoV-2 from the employees of the two farms on which mink-to-human transmission may have occurred did not match the genomic sequences of the virus from people with COVID-19 who lived in the vicinity of either of these farms. Furthermore, the sequences from the three COVID-19 positive employees described in the May 25 report did not match any known viral sequence from COVID-19 patients across The Netherlands. These results support the conclusions drawn in the May 19 report; namely that it is plausible that mink-to-human transmission occurred on these two farms prior to the initial detection of infected mink on either farm, and prior to the time employees began wearing personal protective equipment (PPE) when working with mink.
  • SARS-CoV-2 was not identified in any air samples collected outside the infected mink houses on any of the farms, but it was detected in the initial dust fraction collected inside the mink houses on the first two farms. It is not known whether the virus in the dust fraction is infectious (May 8 and May 15 reports). Given the results noted in the May 15 report, the ban on pedestrian, bicycle, and moped traffic within a 400-meter radius of infected mink farms has been lifted. This holds true for the four already identified farms and any farms that are subsequently identified as infected with SARS-CoV-2.
  • Dutch authorities do not believe infected mink pose a risk to the general public. Risk to farm employees is mitigated with the consistent use of PPE. However, epidemiological studies on transmission of SARS-CoV-2 on mink farms continues to help ensure public health is not compromised.

As of May 20, the Dutch government began conducting mandatory testing for SARS-CoV-2 infection at all mink farms in The Netherlands, and any animal (mink or otherwise) found to be infected with SARS-CoV-2 will require mandatory reporting to the appropriate government authority. In addition, all non-employee visitors to mink farms are not prohibited.

Cats on infected mink farms (May 15 and May 25 reports): The Minister’s May 15 report to Parliament provided results of serological studies on the cats living at the first two infected farms. These cats are feral or semi-feral. Eleven cats were tested via serology and three of the 11 had circulating antibodies against SARS-CoV-2. In the May 25 report, the number of tested cats had increased to 24, with a total of seven (three reported previously, plus four additional cats) testing positive for virus-specific antibodies. SARS-CoV-2 RNA was also detected in one of the seropositive cats, but at such a low copy number that genomic sequencing was not possible. The seven seropositive cats had been infected with SARS-CoV-2, and six were no longer shedding virus. However, the source of the virus (infected mink or infected farm workers) in cats is not known, nor is it known whether the cats transmit the virus to other animals. Additional studies are ongoing to better understand what role, if any, cats on mink farms play in transmission of the virus. Pending results of these additional studies, farm owners have been advised to ensure new cats cannot enter their mink farms, nor existing cats leave.

The Dutch Minister of Agriculture, Nature, and Food Quality notified the OIE via a letter to the Director General, dated April 26, 2020, of the first two infected mink farms. No notifications of the additional infected mink farms or infected cats have been published on the OIE web site, nor are immediate or follow-up notifications available at the OIE World Animal Health Information Database (WAHIS) Interface.

SECTION 2: PET CATs IN SPAIN

On May 8, La Vanguardia, a Barcelona newspaper, reported that a pet cat in the Catalonia region of Spain whose owner had recently died of COVID-19 tested positive for SARS-CoV-2 by RT-PCR. Other people living in the same household were also ill with the disease. The cat was presented to the local veterinarian for complications related to a chronic heart condition, hypertrophic cardiomyopathy. Because of its worsening heart condition, the cat was euthanized. It did not die of COVID-19.

After the cat was euthanized, veterinarians sent its body to the Center for Research in Animal Health in Barcelona, where a necropsy was performed on April 22, and samples were collected from various organs and tissues. Tests (RT-PCR) were run on these samples, and results from the nasal cavity and gastrointestinal tract were “weakly positive” for viral RNA. It is not clear what other samples were tested. On May 12, the AVMA was informed by colleagues in Spain that additional tests were planned, including virus isolation and serology, to determine whether the cat had circulating antibodies against SARS-CoV-2 before it was euthanized.

The OIE was made aware of this cat on May 11, 2020; however, as of May 13, there was no notification published on the OIE-WAHIS Interface.

On May 21, a preprint was posted on the medRxiv site describing results of a Spanish study in which 23 asymptomatic and quarantined mammalian pets from 17 households with confirmed human cases of COVID-19 were tested for presence of viral RND by use of RT-PCR. The 23 pets included 12 dogs, 8 cats, 2 rabbits, and one guinea pig. Two samples were collected from each animal (oropharyngeal and rectal swabs) one time only sometime between three and 41 days after their owners had been diagnosed with COVID-19. Only one cat tested positive, and only on the oropharyngeal swab collected four days after its owner was diagnosed; all other pets tested negative. The positive cat was an 8-year-old female and one of two cats owned by th same person with severe COVID-19 (defined as respiratory involvement with radiological alteration and need for external oxygen support). Follow-up swabs were collected 26 days after the first samples were collected from the two cats belonging to this owner, and both cats tested negative for SARS-CoV-2 by use of RT-PCR. Infection was not confirmed in this one positive at either by repeat sampling and positive RT-PCR results, virus isolation, or detection of virus-specific antibodies.

SECTION 3: PET CATS IN FRANCE

In a May 1, 2020 press release, the joint virology research unit of the National Veterinary School of Alfort, the French National Agency for Food, Environmental, and Occupational Health Security, and the French National Research Institute for Agriculture, Food, and the Environment, in connection with the Pasteur Institute, reported that SARS-CoV-2 RNA was detected in samples collected from a cat whose owner was suspected to have COVID-19.

This cat was one of approximately 12 that were part of a study to determine whether cats who were owned by or lived with someone confirmed or suspected to have COVID-19 could become infected with SARS-CoV-2. Rectal and nasopharyngeal samples were collected from each cat and subjected to a quantitative RT-PCR assay that specifically amplified two SARS-CoV-2 genes. Results from the rectal sample of one cat, which had clinical signs of respiratory and gastrointestinal disease, were positive; all other samples collected were negative.

The researchers collaborated with local veterinary practitioners to identify the cats used in this initial study, and plan to continue their surveillance to learn more about how SARS-CoV-2 affects pets.

The OIE was made aware of the SARS-CoV-2 positive cat in France on May 2, 2020 via a ProMED mail notification; refer to the tabulated list above for a link to that notification.

In a May 12, 2020 press release from the National Veterinary School of Toulouse (ENVT), the school reported that SARS-CoV-2 RNA was detected, using viral-specific RT-PCR, in a cat in Bordeaux, France. This represents the second SARS-CoV-2 positive cat in France. This cat, like the previous positive cats from multiple countries, lived in a household with people strongly suspected of having COVID-19. The cat had developed clinical signs of respiratory disease, including a cough, and was examined several times by a local veterinary practitioner. The cough persisted despite treatment with anti-infectious and anti-inflammatory agents. A nasopharyngeal sample was collected from the cat, and analyzed via two separate RT-PCR assays, each amplifying distinct SARS-CoV-2 genes. A rectal swab specimen was also analyzed in the same manner. The nasopharyngeal sample was positive for SARS-CoV-2; however, the rectal swab specimen was negative.

The RT-PCR tests were performed at the Host-Pathogen Interactions (IHAP) research unit of ENVT, which together with the University Veterinary Hospital Center for Companion Animals is studying suspected cases of COVID-19 in domestic carnivores, particularly cats and ferrets, two species shown to be susceptible to SARS-CoV-2 via experimental infection. The study of COVID-19 in domestic carnivores at ENVT is a collaborative project with the National Veterinary School of Alfort and VetAgroSup in Lyon.

The OIE was made aware of this cat by receipt of the ENVT press release on May 12; however, as of May 13, there was no notification published on the OIE-WAHIS Interface.

SECTION 4: PET DOG (PUG) IN USA (NORTH CAROLINA)

On April 28, 2020, a local news station reported that a pug in North Carolina had tested positive for COVID-19. This dog was one of three pets (2 dogs and a cat) belonging to a family in which 3 of the 4 family members were confirmed to have COVID-19 in March. All 3 had recovered by April 1 when they joined a new COVID-19 study being conducted by Duke University. Blood and oral and nasal swab specimens were collected from the human family members, and oral swab specimens from the three pets on April 1. The samples from the pets were tested, using a SARS-CoV-2 specific RT-PCR assay. Only the sample collected from the pug tested positive. Although the owners had noted the pug acting mildly ill while they were sick with COVID-19, it is not clear whether the clinical signs in the dog were related to SARS-CoV-2.

Additional samples, including oral and rectal swab specimens and blood, were collected from the three pets in the household by public health veterinarians and subsequently submitted to the US Department of Agriculture (USDA) National Veterinary Services Laboratory (NVSL) for confirmatory testing.

On May 27, the USDA reported that the NVSL had conducted confirmatory testing but was unable to verify infection in the Pug. No virus was isolated, and there was no evidence of an immune response using the available tests. It was suggested that the weak detection by PCR from the original oral swab might be the result of contamination from the COVID-19 positive household.

Because confirmatory testing did not verify infection in the Pug, the USDA did not submit a report to the OIE.

This case exemplifies why it is critical for confirmatory testing to be completed before reaching a final conclusion as to whether a pet is truly infected with SARS-CoV-2.

SECTION 5: PET CATS (2) IN USA (NEW YORK)

On April 22, the CDC and the US National Veterinary Services Laboratories (NVSL) announced the first pets with confirmed cases of SARS-CoV-2 infection in the United States. One cat lived in Nassau County on Long Island, and the other in Orange County, which is approximately 65 miles NNW of Manhattan.

Both cats had clinical signs of a mild respiratory illness, and both tested presumptive positive for SARS-CoV-2 at a private veterinary laboratory, which then reported the results to state and federal officials. Confirmatory testing (repeat RT-PCR and sequencing as well as serology) was conducted at the NVSL and included collection of additional samples.

This first cat was an indoor-outdoor cat whose owner had no symptoms of COVID-19 and was never tested. However, it lived in an area with a high number of human COVID-19 cases, and it was tested by a veterinarian after it showed mild respiratory signs. It was presumed that that this cat was infected by either its owner, who was asymptomatically infected with SARS-CoV-2, or by another infected person in the neighborhood.

Samples from the second cat were taken after it showed clinical signs of respiratory illness. The owner of that cat had tested positive for COVID-19 prior to the cat becoming ill. Another cat in the household never exhibited clinical signs of illness; results of testing done at the NVSL for this cat were negative.

Both positive cats are expected to fully recover. The NVSL-confirmed positive results were reported to the OIE on April 22, and a follow-up report was submitted on April 29.

SECTION 6: PET CAT (1) AND DOGS (2) IN HONG KONG

At the onset of the COVID-19 outbreak in Hong Kong, government officials with the Agriculture, Fisheries and Conservation Department (AFCD) recommended that mammalian pets, including dogs and cats, from households with persons hospitalized because of COVID-19 should be cared for in quarantine and tested for infection with SARS-CoV-2. As of April 15, 30 dogs, 17 cats, and 2 hamsters had been held at the AFCD quarantine facility. However, only two dogs and one cat had tested positive for SARS-CoV-2. None of the animals in quarantine, including the three positive animals, developed clinical signs of respiratory disease, and at least seven animals have been released from quarantine, including all pets that tested positive.

Dog 1 (Pomeranian): On February 28, the AFCD reported that samples obtained on February 26 from the nasal and oral cavities of a quarantined 17-year-old Pomeranian whose owner had been diagnosed with COVID-19 had tested “weak positive” for SARS-CoV-2, using a real-time reverse-transcriptase polymerase chain reaction (RT-PCR) test. Results from a rectal swab and fecal sample were negative. The RT-PCR test is sensitive, specific, and does not cross-react with other coronaviruses of dogs or cats. A “weak positive” result suggests a small quantity of SARS-CoV-2 RNA was present in the samples, but does not distinguish between RNA detected from intact virus and that detected from fragments of viral RNA.

PCR testing was repeated on samples collected February 28, March 2, 5, and 9 with continued “weak positive” results on nasal cavity samples. In addition, gene sequencing of SARS-CoV-2 from the Pomeranian and its close human contacts was completed on March 12 and the viral sequences were very similar. Results of a virus neutralizing antibody test on a sample collected March 3 were negative, but further serological testing on that blood sample yielded positive results, suggesting the Pomeranian had developed an immune response to the virus. Virus isolation was performed with negative results. Results of RT-PCR conducted on nasal samples on March 12 and 13 were also negative, and the dog was released to its owner on the following day. The dog never showed clinical signs of respiratory disease during quarantine.

Experts from the School of Public Health of the University of Hong Kong and the College of Veterinary Medicine and Life Sciences of the City University of Hong Kong believe the consistency and persistence of the results suggest the virus may have spread from the infected people to the Pomeranian in this case. Testing was conducted by the laboratories of the AFCD and the School of Public Health of the University of Hong Kong. The latter is an accredited reference laboratory for the WHO for the testing of SARS-COV-2.
Unfortunately, the Pomeranian that tested positive reportedly passed away three days after release. The dog was 17 years old and had ongoing health issues that were likely responsible for the death of this dog, rather than COVID-19. Its owner declined necropsy.

The results of the Pomeranian were initially reported to the OIE on February 29, with follow-up reports on March 7 and March 16. A final report was submitted on March 28.
Dog 2 (German Shepherd dog): On March 19, the AFCD reported that a two-year-old German Shepherd Dog, whose owner had tested positive for COVID-19, had also tested positive for SARS-CoV-2, using RT-PCR. The dog also had positive results of Tests run on samples collected March 19 and 20 also yielded positive results, with tests on samples collected for the next 10 consecutive days being negative. On March 25, the AFCD reported that virus was isolated from one or more samples collected from the German Shepherd Dog, and on April 3, reported that the dog developed neutralizing antibodies to the virus. Another mixed-breed dog from the same residence continually tested negative for SARS-CoV-2. Neither dog developed signs of respiratory disease while in quarantine, and both were returned to their owner.

The results of the German Shepherd Dog were initially reported to the OIE on March 20, with a final report on April 7.

On May 14, an article describing SARS-CoV-2 infection in the two Hong Kong dogs was published online in Nature.

Cat: On March 31, the AFCD reported that a pet cat that lived in a residence with an individual confirmed to be ill with COVID-19 had tested positive, using RT-PCR for SARS-CoV-2 run on oral cavity, nasal, and rectal swab samples collected March 30. Results of testing of oral and nasal swab samples collected on April 1 were also positive. Virus neutralizing antibodies against SARS-CoV-2 were also detected in serum collected before the cat was released back to its owner, but virus was not able to be isolated from any samples collected. The cat was released from quarantine after 14 days and multiple negative PCR tests.

The results from the cat were initially reported to the OIE on April 3, with a final report on May 5.

SECTION 7: CAPTIVE TIGERS (5) AND LIONS (3) IN USA (NEW YORK, BRONX ZOO)

On April 5, the USDA National Veterinary Services Laboratories (NVSL) announced a positive finding of SARS-CoV-2 in samples from one tiger at the Bronx Zoo in New York. The USDA-APHIS reported the positive tiger to the OIE on April 6.

The tiger was one of five tigers and three lions housed in two enclosures at the zoo. Four of these tigers and all of the lions had developed clinical signs of mild respiratory disease over the course of a week. The affected animals were long-term residents of the zoo without any chronic medical conditions, and no new animals had been introduced to the groups for several years. As such, it was presumed that the other large cats with clinical signs of respiratory disease were also infected with SARS-CoV-2. The source of infection was presumed to be transmission from a zookeeper, who at the time of exposure had not yet developed symptoms of COVID-19.

On April 17, the USDA-APHIS provided a report to the OIE indicating that one of the three lions had also been confirmed by the NVSL to be infected with SARS-CoV-2.

On April 22, the Wildlife Conservation Society (WCS) published an update on the tigers and lions at its Bronx Zoo. The zoo’s laboratory partners had developed a fecal sample test that allowed the other large cats to be tested without the need for general anesthesia. The zoo tested all of the tigers and lions described in the initial report except for the original positive tiger. Results from these 7 animals were positive, suggesting that the 8 large cats described in the initial report were all likely to have been infected with SARS-CoV-2. The WCS also reported that the 4 tigers and 3 lions that initially developed clinical signs of respiratory disease were recovering well. Animals in other parts of the zoo, including other large cats, never developed clinical signs of disease, and enhanced biosecurity protocols have been implemented for staff caring for the nondomestic felids in the four zoos overseen by the WCS.

SECTION 8: PET CAT IN BELGIUM

On March 18, the Federal Agency for the Safety of the Food Chain (FASFC) in Belgium was informed by the Faculty of Veterinary Medicine at the University of Liege that SARS-CoV-2 RNA was detected by RT-PCR and high throughput sequencing PCR in the feces and vomit of a cat with digestive and respiratory clinical signs. The cat was owned by a person confirmed to be infected with SARS-CoV-2, but it was not reported whether the sequences of virus in the cat and the owner were similar.

Information was also not available regarding what other conditions potentially leading to respiratory or gastrointestinal signs in this cat were considered or evaluated. The cat reportedly became ill at some point after its owner had returned from Italy, but the date samples were collected in relationship to when the cat’s clinical signs first appeared and how those samples were collected (e.g., directly from the cat, off the floor) are not known. Because other etiologic causes for the cat’s illness were not excluded and little is known about the samples in which viral material was detected, a clear link between the presence of viral material and clinical signs consistent with coronavirus infection cannot be established. The condition of the cat reportedly improved 9 days after onset of clinical signs.

The National Veterinary Services of Belgium provided a brief summary of this cat to the OIE on March 28; however, as of May 13, there was no notification published on the OIE-WAHIS Interface.

On March 23, 2020, provisional emergency advice from the FASFC’s independent Scientific Committee regarding the zoonotic risk of SARS-CoV-2 was published electronically. The provisional report was updated on April 14 and ultimately approved on April 24. The Scientific Committee concluded that:

  • The risk of a SARS-Cov-2 infected human transmitting the virus to a pet dog or cat is low.
  • The risk of a SARS-Cov-2 infected pet dog or cat transmitting the virus to a human is negligible, compared with the risk of transmission via person-to-person spread.
  • On the basis of the current state of knowledge, dogs and cats can be considered an epidemiologically dead end for SARS-CoV-2. This is subject to change as new data become available.
SECTION 9: PET CAT IN GERMANY

On May 13, Prof. Asisa Volz of the Institute of Virology at the University of Veterinary Medicine Hannover (Germany) reported through ProMED-mail (Coronavirus Disease 2019 Update 181) that a cat in Germany was confirmed to be infected with SARS-CoV-2, using RT-PCR performed at the Bavarian Office for Health and Food Safety. This 6-year-old female cat lived together with its owner in a retirement home in Upper Palatinate, Bavaria. The owner had died of COVID-19 on April 12, 2020. There were also two other cats (15-year-old female and 10-year-old male) living in the same retirement home, in which there was an ongoing outbreak of COVID-19. All three cats had contact with the residents of the retirement home, but none of the cats had any signs of respiratory disease.

On April 29, 2020, throat swabs of all cats were collected and analyzed for SARS-CoV-2 by use of a virus-specific RT-PCR. Results from the throat swab collected from the cat belonging to the woman that died was a “weak positive.” Results of RT-PCR on throat swabs from the other two cats were negative. All cats were immediately isolated together at a quarantine facility supervised by the local competent veterinary office, and throat swabs were again collected on May 4. The two negative cats remained negative. The positive cat was confirmed as clearly positive for SARS-CoV-2. All cats have been subsequently transferred to an appropriate quarantine isolation facility at the University of Veterinary Medicine Hannover (TiHo). As of May 6, 2020, none of the cats had developed clinical signs of respiratory disease. All three cats continue to be housed together. The cats will be closely monitored for SARS-CoV-2 infection, including development of specific signs of disease, viral shedding patterns, and seroconversion. RT-PCR positive samples will be further investigated by TiHo and also confirmed and analyzed by whole genome sequencing at the Friedrich-Loeffler-Institut (FLI), Insel Riems, Germany.

The SARS-CoV-2 positive cat was reported to the OIE on May 13, 2020 via the initial ProMED-mail notification (scroll to the “findings in animals” section of the Questions and Answers on COVID-19 page on the OIE web site).

SECTION 10: PET dog IN The Netherlands

On May 15, the Dutch Minister of Agriculture, Nature, and Food Quality provided a report to the Dutch Parliament of a pet dog found to be infected with SARS-CoV-2. The 8-year-old American bulldog was owned by a person with a confirmed diagnosis of COVID-19. The dog had been examined by a veterinarian because of breathing problems. On April 30, the breathing problems became more severe, and the dog was euthanized. Samples were taken and tested in the laboratory. SARS-CoV-2 RNA was not been detected by use of RT-PCR, but antibodies against the virus were detected in a serum sample collected immediately prior to euthanasia. The latter finding indicates the dog had been infected with SARS-CoV-2. However, it is not known whether the dog's breathing problems were the result of an infection with SARS-CoV-2 or due to other causes. It is assumed that the dog became infected via transmission of the virus from its ill owner. The OIE has not yet been notified of this infected dog.

The Dutch government has not changed its existing advice on COVID-19 and the handling of pets: patients with confirmed or suspected COVID-19 should avoid contact with their animals as a precaution, and pets of patients with confirmed or suspected COVID-19 should stay indoors as much as possible.

SECTION 11: CatS IN China

On April 3, 2020, a preprint posted on the bioRxiv site described a serological survey of cats conducted during the initial outbreak of COVID-19 in Wuhan, China to determine whether cats had antibodies against SARS-CoV-2, which would indicate they had been infected with the virus. Blood was collected from 39 cats prior to the onset of the outbreak (March-May, 2019) and 102 cats after the onset (January-March, 2020) and sera stored before testing. Results indicate:

  • Antibodies against SARS-CoV-2 were not detected in any samples collected prior to the outbreak, suggesting that virus was not circulating in Wuhan prior to the onset of the outbreak.
  • After the outbreak, SARS-CoV-2-specific antibodies were detected, using an ELISA, in 15 of 102 serum samples obtained from cats (14.7%).
    • These 15 cats either lived with an owner who had COVID-19 (n=3), at a veterinary clinic (n=6), or on the street as strays until they were moved to an animal shelter after the onset of the outbreak (n=7).
  • It was not reported how many of the 87 cats that were seronegative for SARS-CoV-2 lived with people who had COVID-19.
  • Eleven of the ELISA-positive samples were also positive via a tissue culture-based virus neutralizing test (VNT).
    • The highest titers of neutralizing antibodies (1:360 or 1:1080) were found in the three cats that lived with owners who had COVID-19.
    • Four cats did not have detectable neutralizing antibodies,
    • The remaining four cats had titers <1:40.

The authors concluded that SARS-CoV-2 had infected the cat population in Wuhan during the outbreak. However, the relatively low seroconversion rate that resulted in neutralizing antibodies (6.9% [7 cats] of the 102 cats tested had any level of virus neutralizing antibodies) and low to non-existent titers of neutralizing antibodies in all but the three cats who lived with people diagnosed with COVID-19 (these 3 cats represent 2.9% of total population of cats surveyed; they were the only cats that developed neutralizing antibody titers greater than just above background) suggests that cats may not be readily infected with SARS-CoV-2 under natural conditions. The significance of this seroconversion rate to development of virus-mediated disease in cats or transmission of the virus from cats to other animals, including people, is not known.

The OIE has not been notified of these cats.

SECTION 12: Cat IN Russia

On May 26, the Deputy Head of the Federal Service for Veterinary and Phytosanitary Surveillance in the Russian Ministry of Agriculture submitted an Immediate Notification to the OIE of SARS-CoV-2 in a cat. The report indicated that on May 18, throat and nasal swab samples were collected from this cat and tested by use of RT-PCR for presence of SARS-CoV-2 RNA. The amplified gene segment was sequenced, which confirmed that it was 100% homologous to the expected N gene fragment of the virus. The cat is quarantined and will continue to be monitored. No other information was provided regarding whether the cat had any abnormal clinical signs or was owned or a stray. If owned, the COVID-19 status of the cat’s owner was also not provided.

SECTION 13: PET DOG IN USA (NEW YORK)

On June 2, the USDA NVSL announced the first confirmed case of SARS-CoV-2 in a dog in the United States. This pet, a German Shepherd Dog, lived with one other dog and their two owners in New York state. One of the dogs’ owners had tested positive for, and the second had symptoms consistent with, COVID-19 prior to the German Shepherd Dog developing signs of respiratory illness. The second dog in the household remained apparently healthy. Samples taken from the affected German Shepherd Dog tested presumptive positive for SARS-CoV-2 by use of RT-PCR performed at a private veterinary laboratory, which then reported its results to state and federal officials. Results of further laboratory tests performed at the NVSL on the original and additional samples collected from the German Shepherd Dog confirmed that this dog was infected with SARS-CoV-2. The dog was presumed to have been infected by its owners and is expected to make a full recovery. Results of serological tests conducted by the NVSL on the second dog in the household revealed virus-specific antibodies, indicating that although this dog never developed clinical signs of disease, it had been exposed to the COVID-19 virus.

The USDA case definition for SARS-CoV-2 infection in animals includes the following:

  • Suspect case: Animal determined to be at high risk of exposure to an infected person, and demonstrating compatible clinical signs as determined by an animal health professional.
  • Presumptive positive case: animal tests positive by use of RT-PCR specific for SARS-CoV-2.
  • Confirmed positive case: sequence confirmation of virus either direct from sample or from virus isolate, OR demonstration of SARS-CoV-2 neutralizing antibodies. All confirmatory testing will occur at NVSL.

All cases of SARS-CoV-2 infection in animals within the USA that are confirmed by testing conducted at the NVSL will be posted on the USDA/APHIS Web site and reported to the OIE.