On April 4, 2020, the US Department of Agriculture (USDA) announced that samples from a 4-year-old female Malayan tiger at the Bronx Zoo in New York City tested positive for SARS-CoV-2 by RT-qPCR. The swab samples were collected and tested after two Malayan tigers, three Siberian tigers, and three African lions showed respiratory signs for a week. On April 17, the OIE confirmed that one of the African lions tested positive for SARS-CoV-2 by RT-qPCR. Later on, all these animals and one asymptomatic Siberian tiger tested positive for SARS-CoV-2 by RT-qPCR of stool samples. The five positive tigers live separately in the same enclosure. The three lions live in an enclosure in another zoo area, and they occasionally interacted. The Bronx Zoo also has one Malayan tiger and two Siberian tigers living in a distant enclosure. These three tigers showed no clinical signs. SARS-CoV-2 was identified and characterized in a Malayan tiger. The seven symptomatic animals have improved and are expected to fully recover. In addition, SARS-CoV-2 characterization has shown distinct viral sources for tigers and lions, with similarities between tiger and zookeeper viruses suggesting human-animal transmission, but no identified viral source was found for the infection in lions.
On April 26, 2020, the Dutch Ministry of Agriculture, Nature, and Food Quality communicated SARS-CoV-2 outbreak in two mink (Neovison vison) farms, after respiratory disease and increased mortality. Infection by SARS-CoV-2 has been reported in minks on a farm with 13,000 minks. Additional infections were identified on a second farm with 7,500 adult minks. Three minks with gastrointestinal and respiratory signs were euthanized. Samples of manure, air, and dust collected from the vicinity of the farm are being tested for the presence of the virus. Cats from the farms will also be tested. At least one worker tested positive for SARS-CoV-2 in both farms. It is not surprising that minks are susceptible because they are from the same family (Mustelidae) as ferrets (Mustela putorius furo), and ferrets can be experimentally infected with SARS-CoV-2 and transmit the disease to other ferrets by direct or indirect contact. The infection in minks appears to be a case of human-to-animal infection, once viral sequences of two farms were related to human being sequences, but in separate introductions. In addition, since March 2020, rabbit farms near infected visons have been investigated by the Dutch Ministry of Agriculture, Nature, and Food Quality due to possible susceptibility to SARS-CoV-2.
Experimental transmission study has shown that pigs (Sus scrofa) and chickens (Gallus gallus) were not susceptible to SARS-CoV-2, since none of the animals seroconverted and all samples were negative for viral RNA after intranasal inoculation. On the other hand, fruit bats (Rousettus aegyptiacus) have presented virus replication detected by RT-PCR, in situ hybridization (ISH), and immunohistochemistry (IHC) associated with mild rhinitis.