The world is currently in the grip of a coronavirus outbreak (renamed COVID-19 World Health Organisation), which was first reported in Wuhan, Hubei Province, China on 31st December 2019. The virus originated from Chinese horseshoe bats and jumped species via an intermediate host, thought to be the pangolin – a delicacy in Chinese culture and the world’s most trafficked animal – and from the pangolin to humans.
COVID-19 produces flu-like symptoms in people, the elderly and people with an underlying medical condition are at the greatest risk.
The World Health Organisation declared COVID-19 a Public Health Emergency of International Concern (PHEIC) on 30th January 2020.
The Committee believes that it is still possible to interrupt virus spread, provided that countries put in place strong measures to detect disease early, isolate and treat cases, trace contacts, and promote social distancing measures commensurate with the risk. It is important to note that as the situation continues to evolve, so will the strategic goals and measures to prevent and reduce spread of the infection. The Committee agreed that the outbreak now meets the criteria for a Public Health Emergency of International Concern and proposed the following advice to be issued as Temporary Recommendations.
Coronavirus is a large family of viruses which cause disease in a range of animal and bird species. Several coronaviruses are infectious to humans and are responsible for the common cold producing mild and self-limiting symptoms in most cases. Two coronaviruses, MERS-CoV and SARS-CoV were more pathogenic, causing severe respiratory infections. SARS virus killed 774 people between 2002-2003, MERS has killed 858 people since 2012.
Viruses can infect one species only; for example, feline herpesvirus only infects cats. Herpes simplex viruses types 1 (HSV-1) and 2 (HSV-2) which cause cold sores and genital herpes and infect humans and some primates. Other viruses, such as rabies and Ebola, can infect multiple species, which makes them zoonotic.
Viruses are made up of genome (DNA or RNA) that is a blueprint with instructions for making more viruses and a protein capsid that covers the genome. Most viruses have envelopes that are made up of lipids and surface glycoproteins which are derived from the host cell membranes which help the virus evade the host immune system.
As viruses do not contain the machinery necessary to replicate, they must hijack the machinery from a host cell. To gain entry to the cell, glycoproteins on the viral envelope attach to receptors on the surface of the cell and fuse with the host membrane allowing the virus to enter the cell. Once inside the viruses parasitise the host machinery to produce new viral progeny. COVID-19 uses the same receptor, angiotensin-converting enzyme 2 (ACE2), to unlock the cell as the SARS virus used.
Because viruses are not capable of multiplying without host cells, they are not considered to be living things.
Where did COVID-19 come from, and how did it jump species?
The Wuhan market sells 120 wildlife animals across 75 species which includes badgers, hedgehogs, wolf pups, bats, snakes, peacocks and even koalas. Stressed and often injured animals in cramped and unsanitary conditions, with cages containing different species stacked on top of each other, trading body fluids and feces. Wild and exotic animals can carry viruses that humans ordinarily wouldn’t encounter.
This mix of animals, in cramped and unsanitary conditions, is a recipe for disaster; viruses are shed faster from immuncompromised and stressed animals, which makes it easier for viruses to mingle and potentially make new strains and jump species.
Image credit, Muyi Xiao
The Lancet analysed ten genome sequences taken from the bronchoalveolar lavage fluid of nine patients. 99.98% of the sequences were the same, which tells us that the virus is new in the human population as viruses mutate quickly. They also found that 88% of the nCoV-2019 genome had the identity of two bat-derived SARS-like coronaviruses.
Symptoms of COVID-19
COVID-19 produces flu-like symptoms in people, which includes:
- Shortness of breath
- Muscle aches
- Sore throat
- Chest pain
Can cats and dogs infect humans with COVID-19?
There are alarming reports of pet owners are throwing cats and dogs out of windows due to fear that they can transmit COVID-19. As we know, there are many, many subtypes of coronavirus, some of which do infect cats and dogs, but these strains are non-infectious to humans because they are species-specific. The World Health Organisation states the following:
At present, there is no evidence that companion animals/pets such as dogs or cats can be infected with the new coronavirus. However, it is always a good idea to wash your hands with soap and water after contact with pets. This protects you against various common bacteria such as E.coli and Salmonella that can pass between pets and humans.
Feline coronavirus (FCoVs) infection is usually subclinical, but from time to time, the feline coronavirus mutates, causing feline infectious peritonitis. There is no treatment for FIP, and the disease is almost always fatal. We still don’t know what causes the feline coronavirus to mutate into the deadly form in cats, but we do know that canine and feline coronavirus is not contagious to humans.
What should you do if you are worried you have been exposed to COVID-19?
Contact your doctor and inform them you may have been exposed, they will provide information on what steps to take next to ensure the safety of the general public.
The quarantine period is 14 days, self-isolate during this period to avoid potentially infecting others. Novel coronavirus may be infectious before symptoms develop.
Once again, there is no reason to surrender cats or dogs as they have not been found to transmit COVID-19. Ways to reduce the risk of transmission or infection include the following:
- Wash hands with soap and water for twenty seconds before eating, after contact with animals and when you return home from an outing
- Avoid touching your mouth, nose or eyes unless you have just washed your hands
- Do not go to work or school if you are sick and avoid public spaces to reduce the risk of infecting others
- Sneeze into the crook of your elbow
- Dispose of tissues in a sealed bin
- Avoid unnecessary contact with farm or wild animals
- Make sure meat is thoroughly cooked before consuming
Where to get information
There are still a lot of unanswered questions regarding COVID-19 with authorities working hard to contain the virus and learn more.
This page will be updated regularly to reflect new information as it comes to light.
- World Health Organisation
- Centers for Disease Control and Prevention
- Australian Government Department of Health