COVID-19 (Coronavirus Disease 19)

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COVID-19, or coronavirus disease discovered in 2019, is responsible for a global pandemic.

COVID-19 is caused by a virus called SARS CoV-2, or severe acute respiratory syndrome coronavirus 2, because it’s genetically similar to the SARS coronavirus which was responsible for the SARS outbreak in 2002.

Now, coronaviruses that circulate among humans are typically benign, and they cause about a quarter of all common cold illnesses.

In COVID-19 what happened is that there was a coronaviruses initially circulating among bats, which are a natural animal reservoir, that seems to have mutated and ultimately started causing disease in humans.

The outbreak began in China, but has since spread around the world.

Worldwide, as of August 1st 2020, or roughly 8months into the outbreak, there have been about 18 million confirmed cases of COVID-19 and 681 thousand deaths, resulting in a fatality rate of approximately 4%.

However, current studies suggest that the actual fatality rate is likely to be lower, around 0.7%.

The reason for this is that there are a lot of undiagnosed COVID 19 cases which makes the actual number of cases go up.

Many of these are asymptomatic carriers; in fact the National Institute of Allergy and Infectious Diseases, has estimated that 25 to 50 % of the cases may remain asymptomatic.

During this worldwide pandemic, there are many lessons to be learned from how different countries have responded to the disease.

To explore that, let’s use an epidemic curve which shows the number of new cases in a country seen each day.

The horizontal line represents the capacity of the healthcare system within that country.

Health care capacity accounts for things like the number of beds and ventilators as well as the number of healthcare workers and resources like personal protective equipment or PPE they have available.

Usually, the healthcare system is working near full capacity, so when a pandemic like COVID-19 breaks out, even a relatively small increase in the number of patients can overwhelm the healthcare system.


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