COVID-19 is an infectious disease caused by a newly discovered coronavirus. Coronaviruses are a large family of viruses which cause respiratory illness, ranging from the common cold to more serious diseases (World Health Organisation , n.d.). A virus is a microscopic parasite usually much smaller than bacteria, that lack the ability to reproduce, thrive and survive outside of a host body (Vidyasagar, 2016). Dr. Zissis Chroneos from Pennsylvania State University (Penn State) College of Medicine, Hershey, PA, research focuses on influenza pneumonia and the treatment of influenza inflammatory disease. Dr. Zissis Chroneos said that COVID-19 describes the disease caused by a novel Coronavirus (CoV) known as SARS-CoV-2 (Hellenic News , 2020). SARS-CoV-2 belongs to the genetically related severe acute respiratory syndrome related family of Coronavirus. The strain is highly contagious strain with mixed mode of contact and airborne transmission. The virus originated in Wuhan City, China and was a new strain of coronavirus that has not been detected prior (Health Direct, 2020). First reported in Wuhan at the end of 2019. Prof Stephen Turner, head of the department of microbiology at Melbourne’s Monash University, says what’s most likely is that virus originated in bats (Readfearn, 2020). SARS-CoV-2 can also infect cats and ferrets. Dr Zissis Chroneos said that it originated as a zoonotic infection from bats via intermediate species. The main natural source of different Coronavirus species are bats. Pangolins could be the putative intermediate species as found by molecular evidence (Hellenic News , 2020). Symptoms of the disease can include low-grade fevers, persistent low-grade headaches, coughing, unexplained pain, dyspnea and malaise (Department of Health, 2020). Most people with COVID-19 have mild to moderate symptoms. The people at most risk in Australia are people 70 years or older, people 65 years or older with medical conditions, Aboriginals and Torres Strait Islanders who are 50 years or older with a chronic medical condition as well as people with compromised immune systems (Health Direct, 2020).
Different strands of Coronavirus have previously caused outbreaks or pandemics, none quite as large as SARS-CoV-2. COVID-19 is the third member of the beta CoV family in the last 25 years to cause a pandemic and rapid widespread from humans to human transmission (Hellenic News , 2020). In 2002 and 2003, severe acute respiratory syndrome coronavirus (SARS-CoV) initiated an outbreak of the disease severe acute respiratory syndrome (SARS) in mainland China and Hong Kong. It was thought to originate in the Chinese ‘wet market’ (Woodley, 2020). Only spreading to 29 countries prior to being contained. The disease quickly spread through respiratory droplets and contaminated surfaces. Mainly affecting people 60 years or older, almost identical to the age of people most impacted by COVID-19. The strain had the same symptoms as COVID-19 being fever, respiratory symptoms, cough and malaise. Even though the death rate for SARS was higher than COVID-19, COVID-19 has already claimed more lives. As well as mote social and economic repercussions (Healthline, n.d.). The virus ended due to it not having the fitness to persist in the human population. The outbreak had 8098 cases across 29 countries and had 774 deaths worldwide. Whilst, COVID-19 has impacted 210 countries so far (Worldometers, 2020). With 2,552, 491 reported cases and 177,234 reported deaths world-wide as of April 22, 2020 (Worldometers, 2020). Another strand of Coronavirus that has caused outbreaks is Middle East respiratory syndrome also known as MERS-CoV. Which is a viral respiratory disease caused by a novel Coronavirus. Symptoms which are shared with COVID-19 being ever, cough and shortness of breath as well as pneumonia being a common symptom but not always present. The virus does not pass easily from person to person unless close contact occurs (World Health Organisation, 2019).The fist outbreak of MERS occurred in 2012 and multiple have occurred since (The Conversation, 2020). Approximately 80% of reported cases occurred in Saudi Arabia, although it has been recorded in 26 other countries. One of which include South Korea, recording 186 cases and 36 deaths between May and July in 2015 (Woodley, 2020). From September 2012 to November 2019 there have been 2494 confirmed cases and 858 associated deaths (World Health Organisation, 2019).
SARS-CoV-2 can spread multiple ways, much like any living organism viruses try to multiply and spread in order to maintain survival (Queensland Health, 2020). Even though, the basic outlines of transmission for COVID-19 have not fully been determined there are some factors that could play a role in the spreading of COVID-19 (Ghose, 2020). SARS-CoV-2 spreads from person to person is through droplets that an infected person sneezes or coughs out much like the flu (Queensland Health, 2020). Large droplets of virus-laden mucus are the main mode of transmission. The droplets that carry the SARS-CoV-2 enter the body through the mucous membranes of the face such as eyes, nose and mouth. Thus, offering a direct path to the throat and lungs. The droplets may fall directly to one’s nose, mouth and eyes if close enough to the infected person. Therefore, the virus enters the system straight away. Another way is it that droplets may fall to a surface and then one touches the contaminated surface. The virus could then move into the mucus membranes if the persons hands are not washed. Or the infected person could cough into their hands and then touch the surface which you could then touch. Another way to spread the virus could be direct membrane-to-membrane contact such as kissing or sharing items that touch one’s mouth, eyes or nose such as cutlery, water bottles, cups, straws and cosmetics (Ghose, 2020). A whole new way that diseases can spread without being coughed or sneezed in large mucus droplets is through aerosol transmission. This means that it has to be able to suspend in the air for long enough to infect someone who passes by. When someone emits virus particles it may be in a range of sizes and some particles are small enough to be known as aerosols or fine particles. Which may be suspended in the air for multiple hours and can move with air currents.