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COVID-19: Making Sense of the Numbers

Varying Mortality Rates Paint an Intriguing Picture

The pandemic has been going for months now, and we still have not been able to answer the single most important question: what is the death rate?

Right now, we are seeing numbers that are all over the place, with dramatic fluctuations from country to country. In Germany, the mortality rate is under 1 percent, while in Italy it has ballooned to an alarming 10 percent. This is a big disparity. The problem is - there have not been enough tests conducted to know how many people have been infected. As testing ramps up, the mortality rates may fall, because 4 out of every 5 people are spreading the virus without even knowing it—as their symptoms are so mild they don't realize they have it or they have none at all (Report of the WHO-China Joint Mission, 2020). The German experience may give us a window into the future. While most countries have focused their testing on the sick, Germany has been testing its citizens who present with mild symptoms, regardless of age, hence they have tested a significant number of mild cases. The result is a much lower death rate. In theory, this low number could be pushed down even further if we include the 60 percent of cases that have no symptoms.

The Death Rate in China Keeps Trending Down

A study published on March 19 in Nature Medicine found that the death rate in Wuhan was 1.4 percent (Wu et al., 2020). Early in the outbreak, the World Health Organization placed the figure at 5.8 percent. One early study even had the rate as high as 12 percent (Mizumoto and Chowell, 2020).

There are several reasons why the new study of Wuhan patients is significant: It did not include people who were asymptomatic. Other factors will further influence mortality rates:

Poor healthcare. China has an inferior health care system in relation to Western countries and significantly higher rates of people dying of secondary infections compared to the West.

The smoking epidemic. China has the largest population of smokers in the world—over 40 percent of adult Chinese males smoke, while the rate is under 3 percent for adult females. Smoking elevates your risk for numerous health problems, and pre-existing conditions play a big part in the mortality rate for COVID-19. One Chinese study of 78 patients who were suffering from Coronavirus-related pneumonia found that the likelihood of the disease progressing was 14 times higher in those with a history of smoking (Lui et al. 2020).

Breathing polluted air. China also has a huge air pollution problem. Recently, it was so bad in Wuhan that protests broke out (Griffiths, 2019). Many people in China have lung problems when compared to the West, and hence, compromised health.

Why are the Italian Numbers so High?

While the mortality rate in Italy is alarming, most of the deaths are in the north, which has some of the most polluted air in Europe. Before the outbreak, a leading environmental scientist described air pollution in the region as “frightening” and “alarming” (Cornu 2019a, 2019b). It may be no coincidence that the three areas hit particularly hard at this time, in China, Italy, and Iran—have some of the worst air pollution on the planet. Residents in Hubei Province where Wuhan is, and in the city of Tehran, often breathe in the equivalent of a pack of cigarettes a day (Davis, 2020).

Another factor affecting the mortality rate in Italy involves health reporting protocols. Professor Walter Ricciardi, an advisor to the Italian Health Ministry, observes that the high death rates there may reflect the way that deaths are recorded. “The way in which we code deaths in our country is very generous in the sense that all the people who die ... with the coronavirus are deemed to be dying of the coronavirus," he has said. “On re-evaluation by the National Institute of Health, only 12 percent of death certificates have shown a direct causality from coronavirus, while 88 percent of patients who have died have at least one pre-morbidity—many had two or three” (Newey, 2020). Pre-morbidity refers to having serious health issues prior to the onset of a disease.

The spread of infection could also be much higher in Italy because of the custom of kissing people on their cheeks when meeting. Italy also has one of the oldest populations in the world, with the country's average age of death from Coronavirus at 81. Yet another factor contributing to the situation in Italy is the prominence of the country's anti-vaccination movement (Broder, 2019), as elderly Italians who have been fighting off the flu would also be at greater risk of dying of COVID-19. In one recent study of 83,000 elderly residents in Northern Italy, just 50 percent had been vaccinated for flu (Bellino et al., 2019).

Be Vigilant, but There is Need to Panic

What makes this virus so challenging is that many people don't even know they have it and are spreading it to others. It also spreads very easily. As a result, demand for hospital beds in some places is outstripping supply. But there is light at the end of the tunnel. The New England Journal of Medicine has published an editorial by immunologist Dr. Anthony Fauci. Based on the downward trend in the mortality rate in China, he and his colleagues wrote:

If one assumes that the number of asymptomatic or minimally symptomatic cases is several times as high as the number of reported cases, the case fatality rate may be considerably less than 1%. This suggests that the overall clinical consequences of Covid-19 may ultimately be more akin to those of a severe seasonal influenza (which has a case fatality rate of approximately 0.1%) or a pandemic influenza (similar to those in 1957 and 1968) rather than a disease similar to SARS or MERS, which have had case fatality rates of 9 to 10% and 36%, respectively” (Fauci et al., 2020).

Mortality rates for Covid-19 in the United States are all over the place and represent dramatically different outcomes. Estimates on the number of potential deaths in the United States have ranged from 2 million to 20,000. One way to better understand the threat is to compare these figures to the seasonal flu, which has a death rate of about 0.1 percent. Two years ago, the flu killed 61,000 Americans. Of course, there is no vaccine for Covid-19, while there is for the flu. It is only when we better understand the true mortality rate, once testing becomes more common, will we be able to get an accurate picture as to what the rate is. But based on the number of asymptomatic cases that have yet to be counted, there is every reason to believe that Dr. Fauci and his colleagues may be right.


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