Many people who fall ill with the new coronavirus disease will experience mild, flu-like symptoms.
But COVID-19 is not the same as flu.
So far, the novel coronavirus appears more contagious, more deadly and has more potential to overwhelm the health system.
Here’s how the two compare.
The ways COVID-19 and flu are similar
Viruses cause both influenza and COVID-19, and their first symptoms are often very similar.
They can cause fever, coughing and a sore throat, and in both cases, symptoms can vary from mild to fatal.
While none of us have any immunity to the new coronavirus, research shows our immune systems respond to it in the same way as to influenza.
The immune cells that emerge in the blood before patients recover from COVID-19, are the same cells we see in people before they recover from flu.
That means frequent and thorough handwashing, covering coughs and sneezes with your elbow or a tissue, and if you’re sick, avoiding contact with others.
COVID-19 is more contagious
Epidemiologists use a couple of different measures to work out how far and fast a virus is likely to spread.
One of these is called the “basic reproduction number”, otherwise known as the R naught, or R0.
The R0 refers to the number of secondary infections generated from one infected individual, said Sanjaya Senanyake, an infectious diseases specialist from the Australian National University.
“For COVID-19, that number is 2 to 2.5. That means one person with COVID-19 goes on to infect two or two-and-a-half people,” Dr Senanyake said.
That figure is higher than for flu, for which the R0 varies, but is estimated to be around 1.3.
That means the new coronavirus is about twice as contagious as influenza.
COVID-19, however, appears to spread a little slower than flu, which has a shorter incubation period (the time from infection to the appearance of symptoms).
“When we talk about infectiousness … the other measure is something we call a serial interval, which is the speed between infection,” Dr Senanyake said.
While pre-symptomatic transmission (when the virus spreads before symptoms appear) is a major driver of transmission for influenza, that’s not likely to be the case with COVID-19.
While there are people who can shed the COVID-19 virus 24-48 hours prior to showing symptoms, according to the World Health Organisation (WHO), this doesn’t appear to be a major driver of its spread.
COVID-19 is more deadly
Most people who get the new coronavirus or flu will get better.
“Eighty per cent of people with COVID-19 just have a mild to moderate illness that lasts about two weeks,” Dr Senanyake said.
However, the fraction of people who develop severe disease with COVID-19 is higher than it is for influenza.
According to the WHO, 15 per cent of COVID-19 cases are severe infections that require oxygen, and 5 per cent are critical infections, requiring ventilation.
The mortality rate for COVID-19 also appears to be higher than for influenza, especially seasonal influenza.
“For seasonal flu it tends to be about 0.1 per cent,” Dr Senanyake said.
That equates to around one in 1,000 people.
At a rate of 1 per cent, COVID-19 would be about 10 times more deadly than seasonal flu, which is estimated to kill between 290,000 and 650,000 people globally every year.
But the true mortality rate will take some time to fully understand, as there are many mild cases likely not yet reported.
Those most at risk
The people in the community most at risk for severe influenza are:
- pregnant women,
- elderly people,
- people with chronic medical conditions (such as asthma),
- people who have compromised immune systems.
For COVID-19, those most at risk are:
- people who have recently been in a high risk country or region (mainland China, Iran, Italy or Korea),
- people who have been in close contact with someone who has a confirmed case of COVID-19,
- elderly people,
- people with chronic medical conditions,
- people who have compromised immune systems,
- Aboriginal and Torres Strait Islander peoples (as they have higher rates of chronic illness).
But health experts have warned younger adults shouldn’t be complacent about their risk, as it’s not impossible for them to have a severe form of the disease or even die from it.
While children are key drivers of influenza transmission in the community, initial data from the COVID-19…
Source Website How does coronavirus COVID-19 compare to flu? – Health