COVID-19 vaccination uptake and green pass certification in Italy

By Ekaterina Kochergina and Tommaso Ramella

Presented at the ResPOnsE COVID-19 Workshop: Two years of COVID-19 in Italy. Values, attitudes, and behaviors in the pandemic period 2020-21.

Introduction

In this brief analysis, we explore the patterns of COVID-19 vaccination uptake in a sample of adult Italians in the period between the summer and autumn of 2021.

The acceptance of COVID-19 vaccines is far from absolute in many European countries (Heyerdahl et al. 2022). This is a concern because low vaccination acceptance and low vaccination rates put national health systems at higher risk of malfunctioning through increases in the number of infections, hospitalizations, and deaths (Callender 2016; Watson et al. 2022).

Against this background, we focus our attention on differences in COVID-19 vaccination uptake related to age, gender, and level of education. Moreover, considering that Italy’s immunization plan initially prioritized certain groups of workers, we explore differences between workers in the private and public sectors and we explore whether vaccination rates change over time among the two groups.

Anti-COVID vaccination uptake and green pass certification in Italy

Italy’s immunization plan, rolled out in December 2020, declared a prioritization strategy to vaccinate firstly healthcare workers, nursing home residents, and people over 80 years of age.

By April 2021, the Italian government issued a compulsory vaccination mandate for all doctors, dentists, and health professionals. By August, to access many venues it was necessary to hold the so-called Green Pass, that is, either a certificate proving vaccination status or negative swab test results. In the latter case, the pass was valid for 48h after the test.

At the end of the summer, the Italian government required the Green Pass certificate to be mandated in all private and public workplaces starting from the 15th of October. After this date, workers without a valid Green Pass would be considered unjustifiably absent from their workplace and would not be paid for each day of absence.

Workers who were not vaccinated, but planned to use the Green Pass with a negative swab test result, were required to bear the financial cost of the swab test (i.e., around 15 Euros) (Marcellusi et al. 2022).

Data, analysis, and results

The dataset used in this brief report belongs to the ResPOnsE COVID-19 project carried out by the spsTREND Laboratory at the University of Milan. The survey targeted Italian respondents aged 18 or over who were interviewed in four waves. For further information on the data see the ResPOnsE COVID-19 web page.

We chose to work with the 3rd and 4th survey waves because they coincide with the start of mass anti-COVID vaccination in Italy (in June 2021 for all ages) and with the announcement of the Green Pass certification to access cultural venues and to travel in August and to access working places in October.

Using self-reported data on vaccination uptake (“Have you already received the COVID-19 vaccine?”) we constructed a dependent variable, which takes values of 0 if a respondent hadn’t been vaccinated and 1 if the respondent had at least 1 dose of the vaccine.

As independent variables, we used a set of socio-demographic characteristics that had been demonstrated to be significant correlates of vaccination intake (Dubé et al. 2018; MacDonald 2015; Mesch and Schwirian 2015): sex, age, achieved educational level, a binary variable for the labor sector (two major groups “Public sector” and “Private sector”), a binary variable for the wave (3rd and 4th wave of the study) and the interaction between labor sector and the survey wave (specifically between wave 4 and working in the private sector).

The sample for the analysis comprises respondents between 18 and 92 years old who reported being employed. In order to focus on differences between workers employed in the private or public sector, we excluded respondents who were not employed at the time of the survey. The resulting sample consisted of about 5000 respondents.  Results of a linear probability regression model are reported in Figure 1.

Figure 1. Vaccination uptake and independent variables marginal values (N=5,053)

Our results are consistent with existing literature, confirming a significant association between age and educational level with vaccination intake, and no significant differences between men and women.

More people are vaccinated in the autumn compared to summer (in the 4th wave of the survey compared to the 3rd wave of the survey), which is explained by a time effect.

Older people have a higher probability of being vaccinated. This is the effect of the Italian immunization plan when older cohorts had earlier access to vaccination.

Moreover, previous studies found stronger negative attitudes toward vaccination and lower trust in modern vaccine technologies, such as mRNA among younger people (Moscardino et al. 2022), likely backed by the belief that COVID-19 infection is more dangerous for elderly people or people with comorbidities.

Lastly, we found a statistically significant difference in vaccination intake between workers in the private and public sectors: more public sector workers were vaccinated compared to private workers in the summer. However, by the fall, private workers were catching up with vaccination intake, overcoming the difference observed in the previous period.

Discussion

The observed differences between public and private workers could be accounted for by two factors.

The first factor was unequal access to vaccination between the two groups when preferences were being made by the government firstly vaccinating public workers (doctors, teachers, nurses, and first responders).

Second, we suppose that new regulations in the Autumn Green Pass policy (i.e., abandoning negative tests and requiring all workers to have proof of vaccination to be allowed in the workplace) might have had a speeding-up effect on private workers.

In other words, if private workers had been postponing vaccination in late summer or early autumn, with the new Green Pass policy they had a further incentive to get vaccinated quickly. This hypothesis cannot be tested with the available dataset and needs further investigation.

Conclusions

In this work, we explore COVID-19 vaccination uptake among a sample of Italian adults using the ResPOnsE COVID-19 data. We observe significant differences in vaccination intake between workers involved in the private and public sectors.

Similar results are now being reported in other studies across the EU. For example, Mills and Ruttenauer describe cross-country differences in vaccination uptake given diverse contexts for introducing certification. The authors demonstrate age-specific differences in vaccine rollouts in France and Italy.

In both countries, young people (aged 18–24 years and 25–49 years) showed the most vaccine anticipation and uptake around the date of certification implementation for activities like participation in nightclub life and big events (Mills and Rüttenauer 2022).

The authors also demonstrated that the vaccination certificates are not effective when introduced during shortages in vaccine supply and are not effective in setups with average or high uptake, but perform well in countries with low vaccination anticipation (Mills and Rüttenauer 2022).

While we cannot provide a theoretical explanation of the difference between COVID-19 vaccination uptake among private and public workers groups, future research could fruitfully address this area of research with further confirmatory analysis.

Reference list
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Photo by Diana Parkhouse on Unsplash


Ekaterina Kochergina and Tommaso Ramella

Ekaterina Kochergina is a sociologist and a doctoral student at the University Milano Bicocca. She has an MA in research methodology at the Yuri Levada Analytical Centre and is specialized in quantitative research methodology and administration of large-scale surveys. Her research interests cover quantitative survey methodology, social capital, and social trust.

Tommaso Ramella is a Postdoc researcher in economics at the University of Milano Bicocca. His research interests include the labor market, well-being, personality traits, and resilience.