Catalonia stops fourth wave but stagnates at 1,500 daily cases

Santa Coloma de GramenetAgainst all prognosis, Catalonia has controlled the growth and virulence of the fourth wave and has avoided an explosion of new infections and hospitalisations that would overwhelm the health system. The rise has been contained with relative ease thanks, in part, to the restrictions, the vaccination campaign and the good weather which is making it possible to do more outdoor activities and avoid risky interactions. However, the spread of the virus remains constant and at high levels: in the last week 1,500 infections have been diagnosed per day. In addition, the rate of infection or Rt stands at 0.96 and shows that although the epidemic is not accelerating it is not slowing down either.

Catalonia is experiencing a new phase of stagnation, according to Clara Prats, a physicist and researcher at the Computational Biology and Complex Systems Group (Biocom-SC) at UPC. "The fourth wave is a little different from the previous ones: this time there has not been an explosion of cases, the growth has been smooth and sustained over a month, but as we came from high numbers, now the curve of infections has stagnated at high numbers," she explains. The case of hospitals is more evident: when the fourth wave began, the baseline occupancy figure was 1,500 patients on the ward and 400 patients in intensive care units (ICU); now, there are 1,608 patients on the ward and 492 in ICU. "Last September the same thing happened to us: we stagnated at a thousand cases a day and 150 patients in the ICU. The difference is that the current figures are worse, with 50% more infections and triple the number of critical patients," summarises Prats.

Confirmed stabilisation, now would be the time to see the decline in the epidemiological curve, but for now it is either very subtle (hospitals) or has difficulties to materialise (Rt). "We cannot send the wrong message to the population or distort reality: the fact that the epidemic has not spiralled out of control does not mean that the virus has disappeared or is more benevolent. Many people continue to be infected and admitted to hospitals," warns the president of the Catalan Society of Intensive and Critical Care Medicine (SOCMIC), Jesus Caballero, who puts at 50% the increase in admissions to ICUs in recent weeks.

The doctor stresses that very few patients are discharges and at an almost desperate pace. "For every discharge we give, a patient arrives and that is why the figures have just not come down at all. Occupation will only improve when the discharges we give exceed the number of new patients," explains Caballero, who is also the head of intensive care medicine at the Hospital Arnau de Vilanova de Lleida. However, he points out that there is a certain feeling that soon may reach the ceiling of new admissions and, therefore, see a "decline in number of patients".

"Firewall" vaccines

A hypothesis defended by experts consulted by ARA is that vaccination has had an effect on the control of the fourth wave and the fact that Easter has not caused so much havoc. "We believe that it has been able to act as a firewall within the family groups," explains Caballero. The vaccines are not sterilising - they do not completely eliminate contagion - but the fact that there are vaccinated people in a bubble group reduces the possibility of contagion. "The vaccines help us gain weeks against the virus and, as we vaccinate the most vulnerable people, diagnosing 1,500 cases a day will not be associated with serious illness, hospitalisation and mortality," agrees Prats.

Covid mortality is close to 15% but the vaccination campaign is already beginning to reduce the number of deaths, especially among people over 80 years old. Now the priority is to vaccinate the population over 55 years as quickly as possible to release pressure on the health system. To achieve this, we must press the accelerator and vaccinate people who, due to their age (50-70), are more likely to enter the ICU. "At the moment, the system benefits indirectly from the fact that older people from residences no longer enter the hospital and the vaccination of health workers allows the team to be fully active," summarises Caballero.

In favour, for now, of de-escalation

The acceleration of the epidemiological curve due to Easter has been ruled out although there has been a slight upturn in infections and hospitals have a high proportion of patients (half, in some centers) who have been admitted the last ten or fifteen days, coinciding with the incubation period after the holidays. However, this scenario is not very comparable with the forecasts of the experts, who feared an overwhelming avalanche of new positives and sick people. In this sense, Prats admits that the big problem with the coronavirus is that their behaviour is very unpredictable.

"You always expect that any breakthrough in social interaction will force you to take a step back and this is normal. It is important to remain cautious because every time we have relaxed restrictions there has been an increase in infections," acknowledges Prats. However, she explains that the fact that by Easter there was an increase in mobility and there was no acceleration of infections is "a very clear point in favor of the population".

Citizens' responsibility is one of the arguments put forward by the Government for lifting mobility restrictions within Catalonia and experts consulted by ARA ensure that it is a "logical reaction" in response to the evolution of epidemiological data.

"Mobility is not bad if you avoid risky behaviours such as closed environments. A reopening now can lead to a smooth growth that we could control immediately as we have done now," says Prats. Caballero also believes that severe measures have to be short-lived. "The population has to understand the restrictions, and if there is an improvement, it is not daring to relax them. The message that the authorities are sending is key: why didn't people understand that last week when regional containment was extended? Because they told us that we had successfully overcome Easter," explains the doctor.

Caballero also argues that it should be borne in mind that the epidemiological evolution is asymmetrical territorially. There are three areas with a progression more aggressive than the rest if you look at the number of infections per 100,000 inhabitants and the positivity rate: Lleida has 255 cases and a positivity of 10%; Catalunya Central registers a rate of 197 positives and a positivity of 7.3% and Girona is detecting 162 cases with a positivity of 6.9%.

In contrast, in the country as a whole, on average, 134 infections per 100,000 inhabitants are being detected -about 10,350 per week- and positivity has fallen to 6.2%. Barcelona and the metropolitan area, for example, already have around 5%. "It would be good to consider more surgical measures. If we have understood that the virus does not behave equally between autonomous communities and countries, we should apply the same logic in Catalonia," he argues. For now, however, is an alternative ruled out by the Department of Health, which will prioritise mass screenings in the most affected areas.