Created on 07 Mar 2020 ;    Modified on 08 Jul 2022 ;    Translationitalian

Time trend of Coronavirus Covid-19 in Italy

Data updated at 2022-11-24.

Preamble

For those who have consulted this WEB page before 2022-07-08. Given the persistence of the Covid-19 epidemic, we have decided to aggregate data by week instead of using daily data provided by the Ministry of Health. We have also radically simplified the amount of data observed, limiting ourselves to new cases and deaths.

Goal

Here we report the trend over time of the data relating to the COVID-19 epidemic which has hit Italy since February 2020. The source of these data is the Ministry of Health, and the Civil Protection performs their diffusion.

Graphical analysis

Here we have two sections where we report data:

  • of last 32 weeks (about 7 months);
  • and from the official start of (February 2020) to the last update.
Last 32 weeks

Below we report at November 2022 trend of new covid cases and that of deaths, calculated weekly in the last 32 weeks. In particular:

  • the histogram (red vertical bars) shows new covid-19 cases for each week; the relative scale, is on the left;
  • the blue line shows the number of deaths, again per week; in in this case the scale is on the right, and is unitary.
COVID-19, Italy, new cases in the last 32 weeks

While the following graph displays the normalized ratio of deaths per 10,000 new positives during the past 32 weeks. The detail of how this ratio is calculated is described later in this article.

COVID-19, Italy, death rate normalized for 10,000 new cases, last 32 weeks

The whole period of the epidemic

Instead, the following graphs cover the entire period of the epidemic, from February 2020 to today.

Below is the histogram (red vertical bars) of the new cases of covid-19, calculated weekly. On the left there is the scale with the relative values, expressed in millions.

In addition, we also report the number of deaths (blue line), always calculated on a weekly basis. In this case the scale with the values is on the right, and is unitary.

COVID-19, Italy, new cases

One may wonder what relationship there is between the number of deaths and that of new positives. This analysis requires some precautions:

  • first of all it would be useful to compare the result with the death rate for a known illness, such as the flu. The US CDC clearly publishes this report (which you can consult at this address). According to CDC, in the US, there are 28,000 deaths every 29 million flu patients. That is to say 9.6 deaths per 10,000 flu patients. So if we calculate the death ratio compared to the new cases of covid-19 per 10,000 we can make a comparison.
  • Furthermore we consider the fact that if we report the deaths in the week directly with the new positives in the same week, we would have insignificant and exasperated values. This is because the peaks in deaths occur a couple of weeks after peaks in new positives. Doing the ratio on the current week directly, we would have a high number of deaths, derived from the peak of new positives two weeks earlier, compared to fewer new positives in the current week. Consequentially we have to relate the deaths to the new positives from two weeks ago.

With the aforementioned attentions, we can normalize the number of deaths per 10,000 new positives. Excluding the first four weeks, that have enormous values, after the first month of the epidemic we get lower values.

The following graph shows the trend of the normalized ratio between deaths and per 10,000 new positives. Excluding the first 4 weeks.

COVID-19, Italy, normalized death ratio

Observations

Looking at the graph showing the new positives throughout the whole period of the epidemic, the different macroscopic waves are clearly observable. Notice how the first wave, in the spring of 2020, had a number of new positives rather limited (less than 40,000 new positives/week). But mortality was very high, reaching over 5,000 deaths per week.

Next wave, the Delta variant, from winter 2020 to spring 2021, had a number of new cases higher than those of Alfa, reaching over 200,000 cases per week. But the here the mortality, although still high, did not exceed in absolute value the mortality of Alfa.

With the Omicron variant, from winter 2021 to summer 2022, the peak of new cases has soared to over 1 million 200,000 cases in one week. Fortunately, mortality in absolute values is practically halved. At the peak it was around 2600 cases per week.

Thinking about death rates in relation to 10,000 new cases, at the peak of the Alpha variant, we can observe little more than 1400 deaths every 10000 new positives.

While with the Delta variant the the same ratio drops to less than 400 deaths every 10,000 new cases.

As you can guess, with the Omicron variant the relationship under analysis improves, and by a lot. We observe that, at the peak, it dropped below 200 cases for every 10,000 new positives. Arriving in the summer of 2022 at values of the order of a few tens (this aspect can be seen well in the graph for the last 32 weeks). That is to say a mortality (ironic) only 4 or 5 times higher than that of the flu.

Another aspect worthy of consideration is the fact that the temporal diffusion of variants of the virus has gradually increased. The significant incidence of the Alfa variant has declined in a few months: in July 2020 the new related cases were less than 2000 per week, except for a slight recovery in August, probably due to import from the holiday areas and in September, with the reopening of the schools.

But the Delta variant began to dominate in the fall of 2020 to continue to be present until July 2021, when it was replaced by the Omicron. Almost a year of presence.

While Omicron is showing much more resistant, given the values of new cases in both spring and summer 2022. Values, at the summer peak, more than 600,000 cases per week.

Conclusions

What we have observed in relation to the death rate should lead us to think carefully when we listen phrases like: "it is little more than an influence". Even because if the Omicron mutation proved to be much less dangerous than the previous ones, nothing prevents the next variant may be more contagious and more dangerous at the same time. In this respect, the case of the Spanish flu should remind us of something.

Not only. We have seen that summer is no longer a bulwark against the spread of the virus. Probably due to the lifting of restrictions on the use of masks and the lack of compliance by the population with the hygienic and spacing rules.

So we think it is fundamental, even in Omicron times, counteract the mutations of the virus. And to do this we have two weapons:

  • don't get sick, which implies distance, mask and hygiene;
  • vaccinate, to get out of the disease as quickly as possible (with or without symptoms) in case we get sick.

Used data

Below is the detail of the data used to generate the graph, extrapolated from this data source published by the Civil Protection:

national trend by week
year week new_positives new_deaths new_swabs normalized_deaths_by_10000_new_positive_cases positive_cases_by_100_swabs date
2020 9 1686 34.0 21127.0 8558.72 7.98 2020-02-24
2020 10 5681 332.0 28810.0 6454.85 19.72 2020-03-02
2020 11 17372 1443.0 74962.0 3052.61 23.17 2020-03-09
2020 12 34391 3667.0 133503.0 1485.27 25.76 2020-03-16
2020 13 38551 5303.0 195628.0 1040.7 19.71 2020-03-23
2020 14 31259 5108.0 237431.0 1203.17 13.17 2020-03-30
2020 15 27415 4012.0 318732.0 1088.46 8.6 2020-04-06
2020 16 22609 3761.0 346348.0 990.76 6.53 2020-04-13
2020 17 18703 2984.0 401118.0 896.11 4.66 2020-04-20
2020 18 13042 2240.0 396113.0 1033.58 3.29 2020-04-27
2020 19 8353 1676.0 412140.0 1049.92 2.03 2020-05-04
2020 20 6365 1348.0 439048.0 989.79 1.45 2020-05-11
2020 21 4423 877.0 442052.0 1094.28 1.0 2020-05-18
2020 22 3161 630.0 431727.0 1410.95 0.73 2020-05-25
2020 23 1979 484.0 357796.0 1460.33 0.55 2020-06-01
2020 24 1991 446.0 384183.0 522.35 0.52 2020-06-08
2020 25 1912 289.0 363652.0 643.31 0.53 2020-06-15
2020 26 1434 104.0 330249.0 648.54 0.43 2020-06-22
2020 27 1306 123.0 323669.0 696.78 0.4 2020-06-29
2020 28 1466 93.0 300523.0 422.92 0.49 2020-07-06
2020 29 1377 91.0 299238.0 341.32 0.46 2020-07-13
2020 30 1689 62.0 322523.0 301.95 0.52 2020-07-20
2020 31 1970 47.0 356193.0 969.54 0.55 2020-07-27
2020 32 2497 51.0 333079.0 164.2 0.75 2020-08-03
2020 33 3357 191.0 307573.0 119.15 1.09 2020-08-10
2020 34 5438 41.0 450220.0 117.69 1.21 2020-08-17
2020 35 8880 40.0 578704.0 77.7 1.53 2020-08-24
2020 36 9421 64.0 632916.0 102.96 1.49 2020-08-31
2020 37 10084 69.0 598861.0 126.93 1.68 2020-09-07
2020 38 10406 97.0 614696.0 145.11 1.69 2020-09-14
2020 39 11715 128.0 654250.0 153.65 1.79 2020-09-21
2020 40 15462 151.0 697041.0 243.82 2.22 2020-09-28
2020 41 29622 180.0 780608.0 268.38 3.79 2020-10-05
2020 42 59296 377.0 975869.0 250.94 6.08 2020-10-12
2020 43 111550 795.0 1113420.0 230.21 10.02 2020-10-19
2020 44 183577 1488.0 1313916.0 208.9 13.97 2020-10-26
2020 45 225788 2568.0 1406795.0 203.47 16.05 2020-11-02
2020 46 243444 3835.0 1503673.0 208.71 16.19 2020-11-09
2020 47 230349 4594.0 1510190.0 224.62 15.25 2020-11-16
2020 48 176341 5081.0 1425999.0 251.9 12.37 2020-11-23
2020 49 143699 5174.0 1311089.0 297.78 10.96 2020-11-30
2020 50 114885 4442.0 1090062.0 272.1 10.54 2020-12-07
2020 51 112086 4279.0 913399.0 303.96 12.27 2020-12-14
2020 52 95133 3126.0 917012.0 359.81 10.37 2020-12-21
2020 53 107775 3407.0 880142.0 317.51 12.25 2020-12-28
2021 1 120667 3423.0 965114.0 272.15 12.5 2021-01-04
2021 2 104795 3422.0 1315299.0 291.52 7.97 2021-01-11
2021 3 85564 3284.0 1727343.0 322.21 4.95 2021-01-18
2021 4 86272 3055.0 1732691.0 267.06 4.98 2021-01-25
2021 5 83734 2757.0 1696000.0 255.69 4.94 2021-02-01
2021 6 85210 2304.0 1805855.0 232.48 4.72 2021-02-08
2021 7 87435 2141.0 1890358.0 238.58 4.63 2021-02-15
2021 8 116124 1981.0 2073948.0 203.23 5.6 2021-02-22
2021 9 142388 2086.0 2209958.0 196.44 6.44 2021-03-01
2021 10 155934 2360.0 2280459.0 191.81 6.84 2021-03-08
2021 11 153383 2797.0 2267599.0 201.91 6.76 2021-03-15
2021 12 145050 2991.0 2202385.0 222.27 6.59 2021-03-22
2021 13 136312 3097.0 2106755.0 196.09 6.47 2021-03-29
2021 14 101627 3224.0 1854823.0 227.4 5.48 2021-04-05
2021 15 100385 2673.0 2039578.0 193.16 4.92 2021-04-12
2021 16 92568 2311.0 2031573.0 178.9 4.56 2021-04-19
2021 17 82112 1939.0 1988809.0 161.12 4.13 2021-04-26
2021 18 66478 1656.0 1982198.0 160.81 3.35 2021-05-03
2021 19 47942 1323.0 1805643.0 171.25 2.66 2021-05-10
2021 20 33084 1069.0 1655819.0 144.18 2.0 2021-05-17
2021 21 23836 821.0 1526792.0 200.96 1.56 2021-05-24
2021 22 16436 477.0 1242229.0 163.06 1.32 2021-05-31
2021 23 12461 479.0 1277054.0 162.11 0.98 2021-06-07
2021 24 8112 268.0 1311660.0 218.2 0.62 2021-06-14
2021 25 5581 202.0 1215473.0 225.77 0.46 2021-06-21
2021 26 5260 177.0 1208991.0 174.9 0.44 2021-06-28
2021 27 7972 126.0 1168575.0 102.86 0.68 2021-07-05
2021 28 16176 92.0 1283303.0 71.71 1.26 2021-07-12
2021 29 29972 82.0 1435886.0 51.71 2.09 2021-07-19
2021 30 37959 116.0 1483506.0 55.85 2.56 2021-07-26
2021 31 41097 155.0 1462948.0 77.62 2.81 2021-08-02
2021 32 44335 212.0 1432000.0 77.14 3.1 2021-08-09
2021 33 43986 319.0 1396461.0 95.94 3.15 2021-08-16
2021 34 45658 342.0 1614909.0 88.48 2.83 2021-08-23
2021 35 41226 422.0 1901730.0 94.84 2.17 2021-08-30
2021 36 35004 404.0 1933833.0 110.56 1.81 2021-09-06
2021 37 29736 391.0 1966654.0 112.32 1.51 2021-09-13
2021 38 24236 387.0 1978362.0 111.4 1.23 2021-09-20
2021 39 21458 334.0 2002115.0 111.85 1.07 2021-09-27
2021 40 18300 270.0 1930204.0 155.74 0.95 2021-10-04
2021 41 17602 240.0 2393249.0 155.66 0.74 2021-10-11
2021 42 23305 285.0 3324669.0 122.29 0.7 2021-10-18
2021 43 30792 274.0 3202869.0 126.66 0.96 2021-10-25
2021 44 36095 285.0 3087166.0 111.37 1.17 2021-11-01
2021 45 51318 390.0 3463133.0 96.85 1.48 2021-11-08
2021 46 65460 402.0 3697483.0 79.59 1.77 2021-11-15
2021 47 82158 497.0 3836023.0 77.41 2.14 2021-11-22
2021 48 101313 521.0 3999354.0 79.95 2.53 2021-11-29
2021 49 116499 636.0 3657401.0 83.26 3.19 2021-12-06
2021 50 163648 810.0 4376218.0 63.25 3.74 2021-12-13
2021 51 258143 970.0 4986419.0 53.92 5.18 2021-12-20
2021 52 680688 1035.0 6192041.0 30.35 10.99 2021-12-27
2022 1 1108961 1392.0 6611935.0 21.81 16.77 2022-01-03
2022 2 1219324 2066.0 7638066.0 21.54 15.96 2022-01-10
2022 3 1165753 2419.0 7409388.0 22.49 15.73 2022-01-17
2022 4 976223 2626.0 6946828.0 22.99 14.05 2022-01-24
2022 5 694173 2622.0 6023076.0 28.44 11.53 2022-01-31
2022 6 481681 2244.0 4522069.0 32.61 10.65 2022-02-07
2022 7 363398 1974.0 3447950.0 36.52 10.54 2022-02-14
2022 8 289598 1571.0 2991358.0 33.87 9.68 2022-02-21
2022 9 255656 1327.0 2642537.0 35.87 9.67 2022-02-28
2022 10 340825 981.0 2780213.0 29.25 12.26 2022-03-07
2022 11 477340 917.0 3151885.0 20.99 15.14 2022-03-14
2022 12 495537 997.0 3311639.0 19.45 14.96 2022-03-21
2022 13 479724 1002.0 3240001.0 19.57 14.81 2022-03-28
2022 14 439580 964.0 4135788.0 22.77 10.63 2022-04-04
2022 15 416362 939.0 2770358.0 22.19 15.03 2022-04-11
2022 16 420457 1001.0 2521554.0 20.86 16.67 2022-04-18
2022 17 364817 924.0 2369443.0 20.7 15.4 2022-04-25
2022 18 291534 877.0 2007367.0 24.29 14.52 2022-05-02
2022 19 256447 755.0 1785016.0 24.06 14.37 2022-05-09
2022 20 187156 708.0 1578425.0 20.3 11.86 2022-05-16
2022 21 138122 617.0 1353911.0 32.0 10.2 2022-05-23
2022 22 114426 380.0 1078784.0 28.84 10.61 2022-05-30
2022 23 144333 442.0 1160749.0 26.4 12.43 2022-06-06
2022 24 219234 330.0 1232380.0 20.21 17.79 2022-06-13
2022 25 350017 381.0 1554587.0 16.03 22.52 2022-06-20
2022 26 528722 443.0 1988512.0 15.49 26.59 2022-06-27
2022 27 662236 561.0 2418223.0 14.35 27.39 2022-07-04
2022 28 652044 819.0 2644490.0 18.57 24.66 2022-07-11
2022 29 509060 950.0 2354900.0 20.63 21.62 2022-07-18
2022 30 376763 1211.0 1959866.0 24.52 19.22 2022-07-25
2022 31 272156 1050.0 1577590.0 24.32 17.25 2022-08-01
2022 32 186133 924.0 1232988.0 33.58 15.1 2022-08-08
2022 33 150954 662.0 965776.0 32.13 15.63 2022-08-15
2022 34 156055 625.0 1023784.0 24.16 15.24 2022-08-22
2022 35 131788 485.0 1018577.0 28.0 12.94 2022-08-29
2022 36 110014 377.0 964808.0 27.45 11.4 2022-09-05
2022 37 113008 369.0 936020.0 23.89 12.07 2022-09-12
2022 38 142518 302.0 1032303.0 25.89 13.81 2022-09-19
2022 39 225904 270.0 1216814.0 20.76 18.57 2022-09-26
2022 40 286501 369.0 1417512.0 21.15 20.21 2022-10-03
2022 41 284270 469.0 1507797.0 19.7 18.85 2022-10-10
2022 42 247519 606.0 1446463.0 22.06 17.11 2022-10-17
2022 43 201466 560.0 1282700.0 24.07 15.71 2022-10-24
2022 44 167298 546.0 1106423.0 31.74 15.12 2022-10-31
2022 45 183332 485.0 1144580.0   16.02 2022-11-07
2022 46 224180 531.0 1232125.0   18.19 2022-11-14

Enjoy. ldfa