It is now abundantly clear that COVID-19 is not "just the flu" as Italy grapples to contain the virus. The country has taken surpassed the death toll of China since it recorded 5,476 deaths with a fatality rate of 8.3 percent. China has first shown a fatality rate of 2 to 3.4 percent, but a new study shows that the rate is lower than previously known.
The study, published in the journal Nature Medicine, says that the death rate in Wuhan City, where the coronavirus emerged, is around 1.4 percent. The new estimate is based on the latest available data on Feb. 29.
The paper focused on Wuhan City, the epicenter of the outbreak, three months ago. The novel coronavirus first emerged in a wet market in Wuhan City in Hubei Province, China. Since first reported in December 2019, cases have spread across China and now, throughout the globe.
"A key public health priority during the emergence of a novel pathogen is estimating clinical severity," the researchers wrote on the paper.
Novel Coronavirus SARS-CoV-2 Colorized scanning electron micrograph of an apoptotic cell (green) heavily infected with SARS-COV-2 virus particles (purple), isolated from a patient sample. Image captured and color-enhanced at the NIAID Integrated Research Facility (IRF) in Fort Detrick, Maryland. Credit: NIAID
The new figure
The new data shows a significant decrease in the previously known 2 to 3 percent fatality rate. But experts warn that despite the low fatality rate of the coronavirus, it can infect many people, with a majority of the population infected.
The seasonal flu is a human virus, which infects most people now and then. This means that most people have some sort of immunity for the illness. In comparison, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an animal virus that has jumped across to humans. Therefore most people on the planet do not have immunity against the disease.
This explains why most people who are old, frail, and sick with underlying medical conditions are at a higher risk of experiencing severe COVID-19. Their immune systems are already compromised, making it hard for the body to get rid of the deadly virus.
The new death rate raises hopes that the worse complications of the novel coronavirus will be uncommon.
To compare, Italy, the Philippines, and Malaysia have high fatality rates of 8 percent. Malaysia and the Philippines have just started to report local transmissions, making it still too early to look at their death rates.
Still higher than flu
The death rate of coronavirus is much higher than influenza, commonly known as the flu, which infects millions of people each year but only has a 0.1 percent fatality rate in the United States. Influenza is a highly infectious viral illness caused by influenza A or B viruses. It affects the nose and throat and may also affect the lungs.
To arrive at their findings, the authors calculated the estimates based on the latest cases in Wuhan, including 48,557 confirmed patients and 2,169 deaths. The authors also noted that the older a person is, the higher the fatality risk.
People who are over 60 years old had a death risk of 2.6 percent, making the older adults age group five times more likely to die than those with symptoms between the ages of 30 and 59 years old, with a death risk of 0.5 percent. People who are below 30 years old had a fatality risk of 0.3 percent.
More infections
Across the globe, there are now 331,373 confirmed cases of the coronavirus disease (COVID-19), with 140,450 deaths, as reported by the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University (JHU). Many countries and healthcare systems are struggling due to the lack of testing kits, making disease confirmation harder and longer.
Since the COVID-19 outbreak began to pick up steam in Wuhan, health experts have since clamored to understand the nature of the virus. They believe that with the number of infections, many are still undetected.
For instance, in most countries, testing kits are allotted for those with symptoms of the disease. Some countries fail to test other people who may be exposed to the virus since they do not manifest symptoms severe enough to seek medical attention. Further, millions regard COVID-19 as a simple cold or flu, enhancing the spread of the virus.
If more people go undetected and untested, many people are at a high risk of contracting the virus without them knowing it.
"Estimation of true case numbers—necessary to determine the severity per case—is challenging in the setting of an overwhelmed healthcare system that cannot ascertain cases effectively," the authors wrote in the paper.
"Therefore...our approach has been to use a range of publicly available and recently published data sources...to build a picture of the full number of cases and deaths by age group," they added.
In summing up, the researchers say, "Our inferences were based on a variety of sources, and have a number of caveats, but considering the totality of the findings, they nevertheless indicate that COVID-19 transmission is difficult to control. With a basic reproductive number of around two, we might expect at least half of the population to be infected, even with aggressive use of community mitigation measures. Perhaps the most important target of mitigation measures would be to 'flatten out' the epidemic curve, reducing the peak demand on healthcare services and buying time for better treatment pathways to be developed. In due course, but almost certainly after the first global wave of infections, vaccines may also be available to protect against infection or severe disease."
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