I tried to do some digging into Italy. Specifically, studies about bed shortages during past flu seasons or similar trends, for comparison. I couldn't find anything that specific, but I did find some other things.
Italy has several databases tracking each flu season. They put up weekly reports
here. Here's their
methodology (in Italian). You can go back 10 years to get an idea of how each flu season progressed. They report weekly numbers directly from hospitals region-wide. These numbers are based on a hospital monitoring system of lab-confirmed cases in ICU patients. For example, here are the reported numbers for several recent flu seasons:
2019/20 - as of the end of February, 169 serious cases, 24 fatalities
2018/19 - 812 serious cases, 205 fatalities
2017/18 - 764 serious cases, 173 fatalities
2016/17 - 230 serious cases, 68 fatalities
2014/15 - 648 serious cases, 163 fatalities
2009/10 - 259 fatalities, maximum of 37/week (H1N1 pandemic) - 77.2% had 1 or more pre-existing risk factors
Those numbers are very low, but here are some
reasons (Google translated):
The second surveillance system is that of severe and complicated forms of laboratory-confirmed flu in ICU patients. This system monitors the number of deaths attributable to influenza that are observed in the patient population that has a very serious clinical picture.
For the reasons described above, neither monitoring system provides the total number of deaths that seasonal flu causes in Italy each year. For the latter, it is also necessary to underline an additional element to keep in mind. If we analyze the specific mortality data due to flu that Istat provides every year in Italy, the deaths from flu are a few hundred. The main reason is that the flu virus often aggravates the already compromised conditions of patients suffering from other pathologies (for example respiratory or cardiovascular) up to causing their death. In these cases, the flu virus is often not identified either because it is not sought or because death is attributed to general pneumonia.
For this reason, several published studies use different statistical methods for estimating flu mortality and its complications. It is thanks to these methodologies that an average of 8000 deaths from influenza and its complications are attributed annually in Italy.
This
2019 study, which they link to at the bottom of the page, estimates over 68,000 excess deaths from flu over 4 flu seasons (ranging between 7k and 25k), for an average of 17,000 per year. That is purely a result of statistical analysis (estimating excess mortality, not based on actual tests), so not very reliable. But the point is that a lot of cases simply get classified as pneumonia. Many of the Covid cases too probably would've been classified as pneumonia if they hadn't been tested.
So now we check
ISTAT, which records all death certificates. These are the mortality numbers for the past few years (most recent available is 2017):
2017 - 663 flu, 13,516 pneumonia (total respiratory system diseases was 53,272)
2016 - 316 flu, 10,837 pneumonia (total respiratory system diseases was 46,537)
2015 - 675 flu, 11,632 pneumonia (total respiratory system diseases was 48,518)
Over the last 10 years the range for flu is 267-675, for pneumonia 6,905-13,516, and total RSDs 37,771-53,272. So an average of between 3,777 and 5,327 people die of respiratory illness every year in Italy. A graph like the following is misleading in that it only compares coronavirus to lab-tested ICU flu cases:
ISTAT doesn't have a weekly or daily breakdown of respiratory deaths, so it's hard to find a graph to compare to the above image. (The daily average for respiratory disease deaths based on the above numbers is between 103 and 146 per day, or 721-1,022/week, but any given day can be higher or lower than that.) One thing that will be able to give a sense of the impact of the recent coronavirus deaths is Italy's
Sismg system, which records deaths of all causes in people 65+ from 34 cities. Fluctuations give an idea if mortality is above or below average for that time of year. The
last report ends February 29 and shows mortality slightly below what was expected. On that date, Italy had only 8 coronavirus deaths. So in the next weeks as new reports are published, we should be able to see if overall mortality rises or not, i.e. how much of an impact if any the coronavirus cases have had. (However, Bergamo isn't one of the cities included in Sismg, so that needs to be taken into account.)
www.imperial.ac.uk
