Is an old population a contributing factor for the spread of the disease of COVID-19?

Question

There is a public figure/writer on the Internet which plays a sort of "informal journalist", who stated in a tweet (without a source), that "Italy is hit hard, experts say, because they have the oldest population in Europe."

Now this can be interpreted in two ways. That death rates are higher because of this (it makes sense), or that the disease is spread faster because of this. Could this last idea be true?

Is an old population a contributing factor for the spread of the disease, or does the disease infect younger and older populations in the same way?

Answer 1

There are some theories that the COVID-19 outbreak started in hospitals (VOX, March 13, 2020):

Another theory is that intense spread of the virus in the hospital system, before doctors realized there was a problem, may have amplified the outbreak. Some 10 percent of medical workers in Lombardy have been infected, according to a March 3 Washington Post report, and health workers account for 5 percent of those infected in the country.

In hospitals, in general, there are more older people.

There were also several cases of quick spread of infection in nursing homes.

Hospitals and nursing homes are environments where people live close together, so this is why infection can spread quickly among older people.

Younger people get infected in schools, when they travel to areas with lot of infected people and when they engage in contact sports, for example.

One of the reasons for a lot of cases in Italy is that they didn't act quickly when the inefction started.

Answer 2

Although COVID-19 spreads among young people with active social activities, the mortality rate of young people is extremely small. However, the elderly who have relatively little social activity have a high mortality rate.

Italy is the world's second-largest country with the highest proportion of elderly people, so it has a relatively large number of deaths compared to the number of infected people.

Answer 3

The issue is as you state that Italy has a very high elderly population, something like 23% whereas in China it is only 12%. Death rates have been high amongst the elderly.

Italy has had 12 462 confirmed cases according to the Istituto Superiore di Sanità as of March 11, and 827 deaths. Only China has recorded more deaths due to this COVID-19 outbreak. The mean age of those who died in Italy was 81 years and more than two-thirds of these patients had diabetes, cardiovascular diseases, or cancer, or were former smokers. It is therefore true that these patients had underlying health conditions, but it is also worth noting that they had acute respiratory distress syndrome (ARDS) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia, needed respiratory support, and would not have died otherwise. Of the patients who died, 42·2% were aged 80–89 years, 32·4% were aged 70–79 years, 8·4% were aged 60–69 years, and 2·8% were aged 50–59 years (those aged >90 years made up 14·1%). The male to female ratio is 80% to 20% with an older median age for women (83·4 years for women vs 79·9 years for men).

https://www.wsj.com/articles/italy-with-elderly-population-has-worlds-highest-death-rate-from-virus-11583785086

https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)30627-9/fulltext