With the current global situation and the ever-growing number of cases of the infamous COVID-19, it is no wonder that pet owners and vets across the globe are questioning the safety of their animals against the virus.
COVID-19 is less commonly known as SARS-CoV-2. As the name suggests it is the second discovered severe acute respiratory syndrome caused by the coronavirus. Coronavirus is a widely misused term used to refer to the current SARS-CoV-2 outbreak. The World Health Organisation class coronaviruses as “a large family of viruses that can cause illness ranging from the common cold to the more severe MERS (Middle Eastern respiratory syndrome) or SARS (severe acute respiratory syndrome)”. Since 2002 there have been only 3 outbreaks of SARS worldwide. The first outbreak was of SARS-CoV which originated in Guangdong, China and began in November 2002. The second SARS-CoV outbreak began in September 2003 and originated in a Singapore SARS research lab. By December 2003 it had spread to Taiwan via an attendee of a medical conference held in Singapore. This outbreak was not contained until May 2004.The current SARS outbreak is the third outbreak since 2002 and is caused by the newly discovered SARS-CoV-2.
Coronaviruses, originating from the family Coronaviridae, like many diseases are zoonotic, meaning they originate from animals and are capable of crossing the species barrier to infect humans. Surprisingly, the vast majority of all diseases are zoonoses, with 6 out of every 10 known diseases and 3 out of every 4 newly discovered diseases being zoonoses. The coronaviridae family consists of positive-sense single stranded RNA enveloped viruses of which there are 3 orders: Arteriviruses, Roniviruses and Toroviruses creating icosahedral, rod like or pleomorphic shaped viruses, respectively. The good news is that as coronaviruses are enveloped, they are less resistant making them more sensitive to external factors, such as pH, temperature and solvents, and thus are more easily neutralised, causing them to lose their virulence.
So why is the current COVID-19 spreading so fast? In actual fact, COVID-19 May not be spreading as fast as we think. The reproduction number (R0 ) is the number of people that will be infected if in contact with a contagious individual. Currently, in the UK, COVID-19 has an R0 value of 0.7-1.0, and a worldwide mean of 2.6. To put that into perspective, the Spanish flu of 1918 had an R0 value of 1.4-2.8 and the seasonal flu has an R0 value between 0.9-2.1. An example of a highly infectious disease is hand foot and mouth disease, with an average R0 value of 22.25 across China as stated by the National Centre for Biotechnological Information, so respectively, COVID-19 has a relatively low reproduction number.
Having thought to originate from an animal reservoir, most likely bats, it is no wonder that animals across the world have tested positive for COVID-19. The national geographic stated that several countries, for example China where a German Shepherd and a Pomeranian tested positive, have had reports of dogs and cats sick with the virus have been confirmed. As stated by the USDA only 4 cats, 1 dog, 1 tiger and 1 lion have been infected by COVID-19 in the USA. However, there is no evidence, other than the virus likely originated from an animal reservoir, which shows that animals play a part in spreading the disease to humans. In New York, several large cats, including tigers and lions, were confirmed, by way of PCR and antibody tests, to have had the disease after showing signs of respiratory illness, however all of them have fully recovered. Similarly, reports of European Minks (similar to ferrets) on multiple farms in the Netherlands were reported to have had the disease after showing gastrointestinal and respiratory signs. However, the Centre for Disease Control and Protection confirmed that all of these infections were thought to have stemmed from exposure to an infected handler.
Studies conducted by the Centre for Disease Control and Protection showed that “Ferrets, Hamsters and Cats are able to pass on SARS-CoV-2 to other animals of their own species, as well as studies conducted on non-human primates such as macaques, monkeys and marmosets showing the same result. It has been found that the infection is less easily transferred to dogs” - as stated by cdc.gov.uk.
It is important to note that of the pets who got sick, most only had mild illness and fully recovered. There is no exact number for the confirmed cases of COVID-19 in animals, however the United States Department of Agriculture maintains a list showing that only 10 cases have been reported in the USA. It is advised to treat animals and animal quarantine with the same cautiousness as humans, for example, only letting your pet interact with household members and isolating the animal from any infected individuals. However, with no vaccination, only precautions such as good hygiene practices and social distancing measures can be taken to prevent you and your pets from being infected with COVID-19.
Written by Hannah Supple (L6)