What does not work in the new system for deciding the colors of the regions

The case of Sicily, which remained in the white zone, turns the spotlight on the parameters used to decide the anti Covid-19 measures and on the times to put them into practice

(photo: Michele Feola / Unsplash) The issue is not whether the new parameters for the color change of the Italian regions have been chosen too much or too little restrictively. Nor is it whether the measures and closures corresponding to each color are adequate or not. The question, which we have learned and seen to be crucial in the management of the health emergency from Covid-19, is the speed with which we respond to the trend of epidemic curves. In order to intervene promptly - at the regional level - when there is a need and to reopen and relax the measures as soon as the conditions of circulation of the virus allow it.

We are in these days and weeks at test bed of the new system for calculating the color of the regions, which for the first time since criteria and parameters have been revised, are at risk of moving from the white zone to the yellow zone, and so on. As is known, the new parameters have been calibrated taking into account the fact that a large part of the population is now vaccinated, thus shifting attention more to the stress of health facilities than to the circulation of the virus. Curious, however, that there is no indicator that takes into account the actual regional progress of the vaccination campaign, and it would seem to be no coincidence that the first region that could pass into the yellow zone - Sicily - is also the one with the vaccination campaign. which proceeds more slowly. But that's another story.

What teaches the stay in the white zone of Sicily

At least for this week Sicily, like all other Italian regions, will continue to remain in the white zone, waiting for the new update of the ministry della Salute on Friday 27 August. This despite the fact that he was widely predicted to go yellow as early as the beginning of this week, and despite the fact that the circulation of the virus appears not entirely under control. So much so that the Region has decided to impose anti-contagion restrictions on its own initiative in more than 50 municipalities, in which a sort of yellow zone will apply, as well as two municipalities (Niscemi and Barrafranca) in which the rules will be those of the orange zone. The measures will be in force until September 6.

The parameter calculation system itself has also contributed to this strange situation, which could highlight methodological criticalities potentially replicable in other regions. If the three parameters that define the transition to the yellow zone are well known - over 50 weekly cases per 100 thousand inhabitants, the occupancy of hospital beds for Covid-19 patients is over 15% and in intensive care over 10% - is it is precisely the computation of intensive care that appears to be the weak link in the system. And for at least two reasons.

The issue of intensive care

The first, which seems to be a question of goat wool but is not at all, is that the percentage of intensive care is employed calculated using the data updated daily by the National Agency for Regional Health Services (Agenas) as a numerator, while the denominator (i.e. the places available) are recalculated by law only once a month (at the beginning), thus generating an indicator which does not photograph the actual reality of intensive care. Precisely this happened in Sicily, where using the number of ICU places currently available as a denominator, the occupation would have been greater than 10%, while using the data updated to 1 August (when the available places were more than the current ones) employment was 9.2%.

The second, on the other hand, concerns the calculation of the so-called "activatable" places in intensive care, that is, those normally not used but potentially available if needed and the therapies intensive standard are saturated. Where is the problem? It is easy to say: activating the available places even if there is really no need allows you to change the occupancy index of intensive care and perhaps to lower the indicator below one of the conventional thresholds.

Sicily in August has more than 100 intensive care places active more than in July. But it has also happened in many other regions, as evidenced by the fact that in several cases the number of places that can still be activated has dropped to zero in recent weeks or is much lower than a few months ago. Basically, in many cases, intensive care has already been brought close to the maximum state of alert, although the occupation for Covid-19 cases is just a few percent. Of course this flexibility is not infinite (indeed, in many cases it has already been exhausted), but it can contribute to distorting the meaning of the occupancy indicator, leading to the color change later than in theory it would have been expected.

A combination of retarding factors

It is not only the calculation method of intensive care occupation that can generate a certain delay between the epidemiological situation and the measures. Since the introduction of the measures, in fact, several experts have pointed out that the transition from monitoring based essentially on registered cases (with the Rt index as protagonist) to one centered above all on hospital admissions means that our vision on the circulation of the virus is moved forward in time.

As is known, both in the growth phase of infections and in the waning phase, hospitalizations, intensive care and deaths are the last indicators to react and this means determining a passage of color of the regions (in one way or another, ie closing as well as reopening) later than in the past. Of course this is a consequence dictated by the need not to rely as much as before on the less serious cases of the disease, but it is a downside of the new system that should not be forgotten.

To this are added other factors of delay inherited from the past, and partly not eliminable. For example, the new colors of the regions come into effect on Monday based on the decision of the ministry of the previous Friday, which in turn is based on the data of the control room referring to Tuesday, which usually have some delay compared to the actual trend of the epidemic. Not to mention that there are regions that even now, more than a year and a half after the start of the pandemic, communicate data with a systematic time lag.

"Light" yellow zone

Also if it is not strictly an element linked to monitoring, the variation of the rules in force in the yellow zone compared to the previous color system is also worrying as a delaying factor in the reaction to a wave of infections. In practice, in fact, according to the rules in force, a region in yellow should simply reintroduce the obligation of outdoor masks and reduce the capacity in sports facilities and for events such as concerts or festivals, without changing the occupation of the premises, impose curfews or other restrictions. Except for major events, therefore, in everyday life the transition from the white to the yellow zone will make little difference, and therefore it is unlikely that these small changes will have a significant impact on the circulation of the virus.

Putting together all these factors, which add up their effects, the risk is that serious measures are taken (i.e. from the orange zone, since the yellow one is quite mild) only many weeks later than when the surge in Covid-19 begins, making it very it is more complicated to obtain the inversion of the trend and the containment of the circulation of the virus.

Estimating exactly how many weeks is difficult, but to give an idea: two or three as a time difference between the contagion curve and the '' trend of hospital occupations, one as a cumulative delay in the various phases of data transmission, another for the bureaucratic-administrative times for the entry into force of the measures, perhaps some other week reduced thanks to the places that can be activated in the intensive care units that lower the occupancy rates, and finally the need to reach 20% occupancy (ie the orange zone) before the change of color translates into significant containment actions. And all this is true not only in the ascending phase, but also in the descending one, with the risk of being with the restrictions still in place for weeks when the situation is now back under control.


Politics - 14 hours ago

Where will the green pass be mandatory from September?


Ethiopia believes it can replace social networks with local alternatives


Social network countermeasures to protect users in Afghanistan

Topics

Coronavirus Italy Mathematics Coronavirus numbers Vaccines policy Coronavirus vaccine globalData.fldTopic = " Coronavirus, Italy, Mathematics, Coronavirus numbers, Politics, Vaccines, Coronavirus vaccine "

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.