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https://doi.org/10.1177/22799036221105314
Journal of Public Health Research
2022, Vol. 11(3), 1 –6
© The Author(s) 2022
DOI: 10.1177/22799036221105314
journals.sagepub.com/home/phj
Journal o
f
Public Health Research
Research Article
Introduction
Humanity is faced with a new reality. The COVID-19 pan-
demic is putting a strain on health, life, relationships, the
economy, and health systems of every country in the
world, outlining a global scenario that was difficult to
imagine until 2 years ago.1
The difficulty of curbing the various waves of conta-
gion, which were barely contained by lockdown policies
that yielded transitory results and were often opposed by
1105314PMJXXX10.1177/22799036221105314Journal of Public Health ResearchLugoboni et al.
research-article2022
1Department of Medicine, Addiction Medicine Unit, Verona University Hospital, Verona, Italy
2Drug Addiction Unit (Ser. D.), Naples, Italy
3Department of Neurosciences, Biomedicine, and Movement Sciences, University of Verona, Verona, Italy
4Department of General Psychology, University of Padova, Padova, Italy
5Padova Neuroscience Center, University of Padova, Padova, Italy
6Drug Addiction Unit (SerT), ASP Siracusa, Lentini, Italy
*Acciaro Maria, Aieta Francesca, Amoroso Maria Antonietta, Barbero Alessandro, Boca Damiana, Cadamuro Daniela, Castorina Maria, Cirigliano
Domenica, Di Bartolo Sabina, Dispenza Carmelina, Ficili Maria Assunta, Furnari Maria Teresa, Gelmi Martina, Gentile Rossana, Gramignani Donatella,
Iannuzziello Camilla, Indelicato Antonio, Intilla Simonetta, Lacatena Anna Paola, Liuzza Guglielmo, Manasse Daniele, Marrella Giovanni, Musso Franca,
Palmeri Vincenza, Paparella Maria Maddalena, Pecoraro Carmela, Piali Elisa, Pulvirenti Erika, Schirosi Gabriella, Scichilone Livia, Sgroi Viviana, Vaccaro
Rosetta, Vinci Antonella.
Corresponding author:
Lorenzo Zamboni, Department of Neuroscience, Biomedicine and Movement, University of Verona, L.A. Scuro 10, Verona 37129, Italy.
Email: Lorenzo.zamboni88@gmail.com
COVID-19 vaccination and drug users:
Past, present, and future
Fabio Lugoboni1, Luigi Stella2, Lorenzo Zamboni1,3, Simone Campagnari1,
Francesca Fusina4,5 and Ernesto De Bernardis6; GICS*
Abstract
Vaccination against COVID-19 is crucial in the attempt of containing the virus’ spread, but facing a viral pathogen with
such a high prevalence means that vaccination strategies are facing an unprecedented situation. People that use illicit drugs
may have elevated risk of adverse outcomes from COVID-19 given their high prevalence of underlying medical conditions,
including respiratory and pulmonary disease, chronic liver disease, cardiovascular and cerebrovascular conditions, diabetes,
and compromised immune systems. Despite a widespread distribution on the Italian territory, a large presence of health
personnel and a long-standing experience in vaccinations, addiction clinics have yet to be involved in the vaccination campaign
against COVID-19. The aim of this study was to investigate the beliefs of drug users attending some Italian addiction clinics,
in order to envisage any vaccine administration strategies involving the services themselves. A questionnaire used for the
Italian general population to investigate the relative importance of some factors in influencing the propensity to vaccinate
against COVID-19, was administrated to drug users in a multicenter survey. The majority of respondents expressed
general confidence in vaccines and a good willingness to undergo vaccination. Given strong peer networks, high coverage of
treatment and harm reduction interventions, Italian public addiction clinics could play a strategic role in administering the
vaccine in this hard-to-reach population, usefully aiding the global campaign against the virus.
Keywords
COVID-19, addiction, vaccine, addiction treatment
Date received: 19 May 2022; accepted: 19 April 2022
2 Journal of Public Health Research
social protests due to their serious economic, educational,
and social consequences, have identified mass immuniza-
tion as the only strategy to overcome this global health
crisis.2
Vaccination against a viral pathogen with such a high
global prevalence is without precedent. However, it
remains certain that as long as vaccines remain effective, a
higher vaccine uptake will reduce the number of COVID-
19-related deaths, stem the spread of the transmissible
strain of the virus, and reduce risk of the evolution of other,
even more virulent strains in the future.3
Some priority populations have been identified in inter-
national vaccination efforts.4 Phase 1 of the programs will
immunize priority populations, including frontline health-
care workers, quarantine and border staff and nursing
home and disability care residents and staff, followed by
delivering doses to people aged from over 80 to 60 years,
younger adults with underlying medical conditions and
critical and high-risk workers.4
In the most developed countries, vaccination campaigns
have started rapidly, using health personnel and often atyp-
ical places of mass administration. In Italy, for example,
pharmacists, retired doctors, doctors in training of all spe-
cialties were involved, also using large spaces such as bar-
racks and exhibition pavilions.5
But whilst the vaccination campaigns are being rolled
out worldwide, new virus variants are likely to continue to
evolve. Higher transmission rates require a higher level of
immunity to bring R0 below one and more transmissible
virus strains require more people to be vaccinated in order
to keep the viral spread and the disease under control.3
Furthermore, higher transmission rates increase the evolu-
tionary potential of the virus by increasing the input of
new mutations, potentially giving rise to even more viru-
lent strains.6
A major concern is that mutations could eventually give
rise to vaccine-resistant strains. Such vaccine mutants can
potentially be favored during protracted infections in
patients with a weakened immune response.3,6
COVID-19 has disproportionally affected racial/ethnic
minority groups and persons who are economically and
socially disadvantaged. Ensuring equitable COVID-19
vaccine coverage is a worldwide priority. Continued moni-
toring of vaccination coverage by social vulnerability met-
rics is critical for developing tailored, local vaccine
administration and outreach efforts to reduce COVID-19
vaccination inequities.7,8
People reporting use of illicit drugs and alcohol may
represent a high-risk population in this respect, given their
high prevalence of comorbid health conditions.9,10 In par-
ticular, people who inject drugs may be at elevated risk of
adverse outcomes from COVID-19 given their high preva-
lence of underlying medical conditions, including respira-
tory and pulmonary disease, chronic liver disease,
cardiovascular and cerebrovascular conditions, diabetes,
and compromised immune systems. Last but not least,
they reported the highest prevalence of tobacco smoking
ever. Importantly, such conditions may be underdiagnosed
in this population.9–13
In times of crisis, these communities face challenges
such as being unable to access health services or receiving
the same quality of health care as others due to high rates
of social and economic disadvantage, stigma and discrimi-
nation from healthcare providers.12,13
Since the early 80s of the last century, Italy has had a
widespread network of public services, denominated SerD
(Dependency Services), created to counteract the spread of
addiction to illicit drugs and alcohol. These publicly
funded services provide counseling, treatment for drug
withdrawal, methadone and buprenorphine maintenance
programs, drug-free programs, psychotherapy, and other
services. These centers also provide care for medical prob-
lems related to addiction, as well as HIV, HCV, and HBV
testing.14
In Italy, with a population of 58,000,000, there are 558
SerD, each with a coverage area of some 100,000 inhabit-
ants, on average. Currently, 6624 operators are active in
these services, such as health personnel, 1470 doctors and
1970 Professional Nurses. Also considering the staff who
provide psycho-social support, in SerDs there is one oper-
ator every 20.5 drug users (DUs). Globally, in Italy, there
are 136,320 subjects in charge of SerDs, with an average
age of 41 years.15
The Italian SerDs, especially in the 1990s, significantly
contributed to provide clinical data on the response to vac-
cinations, especially anti-hepatitis ones, in injection DUs,
considered the subjects, by far, at greatest risk of contract-
ing such infections. Indeed, up to now more than half of
the international scientific literature on vaccination of
injection DUs, in terms of both adherence to programs and
efficacy in the immune response, comes from the basic
research of these services.16–18 Furthermore, their wide-
spread distribution on the Italian territory, their ongoing
activity over the years, the presence of multi-professional
teams and the completeness of the care provided have
resulted in the highest levels of compliance to vaccination
campaigns in the world.19–21
Aims
Despite a widespread diffusion on the Italian territory, a
large presence of health personnel and a long-standing
experience in the vaccination of their users, the SerDs
have still not been involved in vaccination campaigns
against COVID-19. The aim of this study was to investi-
gate the beliefs of DUs attending some Italian SerDs, look-
ing for possible comparisons with the data available in the
general Italian population, in order to envisage any vac-
cine administration strategies involving the services
themselves.
Lugoboni et al. 3
Methods
A recent document from the World Health Organization
tried to systematize the main behavioral mechanisms that
can influence adherence to the COVID vaccination cam-
paign. The document identified three types of factors that
can increase the propensity for effective vaccination.22
The first factor encompasses the enabling conditions.
Numerous studies have shown that reducing barriers and
making it easy to get vaccinated improves adherence to
vaccination campaigns. Especially in those who are not
strongly opposed to vaccination, it could be crucial to
reduce the inconvenience of getting vaccinated, identify-
ing the actions that can be taken to make it easy to get
vaccinated as well as increasing the accessibility of the
vaccination sites and simplifying logistics.
The second group of factors refers to social influences
and is based on studies showing that social networks have
an impact, both positively and negatively, on people’s
behaviors in the decision to get vaccinated. It is possible to
hypothesize that communicating the importance of vacci-
nation by health professionals and opinion leaders can
increase the propensity to get vaccinated.
The third behavioral category that influences the pro-
pensity to vaccinate is the individual motivation. Scientific
evidence underlines the need to build trust in the initial
stages of vaccination campaigns, to foresee the negative
consequences generated by the lack of vaccination, and
emphasize the positive impact on others deriving from the
vaccination of the individual.22,23
Based on these premises, the present study explored:
first, the attitude toward vaccinations of the DUs of some
Italian SerDs who have joined the initiative, promoted by
the Addiction Medicine Service of the GB Rossi University
Hospital of Verona and by the Italian Society for Drug
Addiction (SITD) toward vaccines and vaccination against
COVID-19, in order to explore the profile of those who are
more or less inclined to get vaccinated.
Second, the issues related to vaccine and vaccination
against COVID-19 on which this particular type of popula-
tion requires more information and their desired communi-
cation channels.
Third, the relative importance of some factors in influ-
encing the propensity to be vaccinated against COVID-19,
which was assessed with a questionnaire.
The questionnaire, based on the one proposed to a sam-
ple of the Italian general population by the Management
and Health Laboratory of the Sant’Anna School of
Advanced Studies and the National Agency for Regional
Health Services—AGENAS,23 was proposed to the DUs
of some Italian SerDs. Participation in the research was
free and anonymous, completely without benefits for
patients. The study began on 1st April, 2021 and ended on
20th April.
The observational sections of the questionnaire asked
the participants to express their degree of agreement with
respect to a series of statements, on a 1–5 Likert scale
whose extremes represent strong disagreement and strong
agreement. In other observational questions, participants
were able to select one or more options from a predefined
list of answers.23
Results
About 525 males (81.3%) and 121 females (18.7%) par-
ticipated in the study, for a total of 646 subjects. The mean
age was 41.14 years (SD 11.48).
Question 1. The risks associated with the COVID-19
disease are greater than the possible side effects of the
vaccine.
Totally or partially disagree: 23.2%
Neither disagree nor agree: 19.8%
Partially and totally agree: 57%
Question 2. The COVID-19 vaccine is a big business
for pharmaceutical companies and therefore it cannot
be trusted.
Totally or partially disagree: 34.9%
Neither disagree nor agree: 21.9%
Partially and totally agree: 43.2%
Question 3. The COVID-19 vaccine was developed too
quickly to be sure it is safe and effective.
Totally or partially disagree: 30.4%
Neither disagree nor agree: 20.6%
Partially and totally agree: 49%
Question 4. The COVID-19 vaccine is the quickest way
to return to normal life
Totally or partially disagree: 18.6%
Neither disagree nor agree: 12.4%
Partially and totally agree: 69%
Question 5. Vaccines are among the safest pharmaceu-
tical products
Totally or partially disagree: 23.3%
Neither disagree nor agree: 13.6%
Partially and totally agree: 63.1%
Question 7. I think it is right to have your parents or
elderly family members vaccinated against COVID-19
as soon as possible.
Totally or partially disagree: 12.7%
Neither disagree nor agree: 11%
Partially and totally agree: 76.7%
Question 8. I think it is right to have your children vac-
cinated against COVID-19 as soon as possible
Totally or partially disagree: 19.4%
Neither disagree nor agree: 17.3%
Partially and totally agree: 63.3%
4 Journal of Public Health Research
Question 9. I think it is right to introduce limitations for
those who, despite having the chance to be vaccinated,
decide not to get the vaccine against COVID-19
Totally or partially disagree: 32%
Neither disagree nor agree: 20.1%
Partially and totally agree: 47.3%
Question 10. On a scale of 1 (poor) to 5 (excellent),
how do you rate the level of your knowledge on vacci-
nation against COVID-19?
1–2: 35.8%
3: 38%
4–5: 26.2%
Question 11. On a scale from 1 (totally discouraged) to
5 (totally encouraged), encouraged would you feel
about getting vaccinated if you felt you were properly
informed about the risks of vaccination?
1–2: 17.7%
3: 22.9%
4–5: 59.4%
All results are reported in Table 1 and Table 2.
Discussion
Although the importance of vaccinating even the most
socially vulnerable people against COVID has been
stressed by several official organizations, given that they
are more difficult to reach there is no scientific literature
regarding the vaccination of DUs directly at their own
clinics. To the extent of our knowledge, this is the only
work that has evaluated the opinion of these subjects
regarding the COVID vaccination.
It is difficult to compare this study with the correspond-
ing national study (AGENAS) for a number of reasons: the
first is methodological—the national study was of a sam-
ple type and analyzed factors related to age, education and
region of origin. It started in December 2020 and ended in
January 2021, involving 12,322 people.23 The second is
linked to the fact that, from a social point of view, those
who are addicted to substances are much more marginal-
ized than the average citizen. With these precautionary
premises, it can be affirmed that our study, while pointing
out a slightly greater opposition toward the anti-Covid
vaccination, globally, compared to the sample study on the
Italian population, underlines a substantial greater propen-
sity to be vaccinated, compared to opposing it, with a wide
range of undecided.
Keeping these caveats in mind, we can affirm that our
study, while highlighting a slightly greater opposition
toward the vaccine in this population compared with the
national survey results, within the DU group has found a
greater proportion of people willing to be vaccinated com-
pared to those that oppose the vaccine, with a wide range
of undecided subjects.
However, some important points should be made. If we
match the general population sample to the age and level
of education (the lowest) of our sample, the results of the
two questionnaires tend to overlap. Indeed, in the national
questionnaire, the older population was clearly more
favorable to vaccination, probably feeling to be more at
risk of serious complications from COVID-19; likewise,
the less educated groups of the general population were
more opposed to the vaccine.23
There is also another very important note to make; the
AGENAS study ended before concerns broke out regard-
ing some particular vaccines. Indeed, since 2012, while
millions of citizens from all over the world were being
vaccinated, several cases of thrombocytopenia, following
the Moderna, Pfizer, but above all Astra-Zeneca vaccines
have been added to the Vaccine Adverse Event Reporting
System (VAERS) in the US and in many other countries.
So far, two mRNA and two adenovirus-vectored vac-
cines have received a conditional marketing authorization
in the EU and other countries.
The Astra-Zeneca vaccine, in particular, has attracted
media attention. Directly or indirectly, this has led to its
suspension in some countries, including Italy, with subse-
quent restrictions related to its supposed thrombotic risk.
Table 1. Distribution of answers to questions 12 and 13.
First source of
information on
Covid vaccines?
Who would you like
to learn more about
covid vaccines from?
Frequency (%) Frequency (%)
Family 71 (11.23) 29 (4.63)
Word of mouth 63 (9.97) 16 (2.55)
TV 340 (53.80) 139 (22.17)
Internet 82 (12.97) 29 (4.63)
Social media 16 (2.53) 12 (1.91)
Newspapers 21 (3.32) 17 (2.71)
General practitioner 15 (2.37) 156 (24.88)
Doctor 7 (1.11) 150 (23.92)
Health institutions 17 (2.69) 79 (12.60)
Total 632 (100) 627 (100.00)
No answer 16 21
Table 2. Question 14: what would you like more information on?.
Role and importance of
COVID-19 vaccinations
Side effects of
COVID-19 vaccination
Conflicts of interest in the field
of vaccines against COVID-19
How COVID-19 vaccines
work
n (%) 251 (38.73) 163 (25.15) 73 (11.27) 121 (18.67)
Lugoboni et al. 5
Some Northern European countries have even ordered it to
be withdrawn from trade.24–27 The great media coverage
that has been given to these events has, in all likelihood,
influenced the result of our study, which took place during
this period of great uncertainty about the safety of some
vaccines, not only limited to Astra-Zeneca.
The majority of respondents expressed general confi-
dence in vaccines as pharmaceutical compounds, perhaps
because they were reminiscent of previous effective vac-
cination campaigns targeting drug addiction risk factors,
such as hepatitis. It should be noted that the universal vac-
cination against hepatitis B, which for almost three decades
has been compulsorily administered to newborns, has, in
fact, led to less attention toward vaccine prophylaxis,12
while the recent campaigns for the eradication of hepatitis
C, which saw the active participation of the SerDs, did not
see an equal attention toward vaccination against hepatitis
from virus A, however highly recommended in liver dis-
ease and DU.26 The sharp decrease in the circulation of the
HIV virus among DUs has also led to a sharp decline in
serological surveillance in SerD.12
Two thirds of DUs have however expressed a clear
intention to vaccinate and vaccinate their children, while
the vaccination intention regarding their parents rises to
three quarters of the sample being in favor, strongly con-
vinced that vaccination is the fastest way to return to
normal.
One of the most negative data is the low level of infor-
mation reported by DUs, especially if we consider the fact
that they continuously attend highly medicalized services
and that, in SerDs there is an operator/user ratio of 1:20. It
seems surprising that the vast majority of the interviewed
subjects learned the information about vaccines from tele-
vision; only a small part has received information from the
doctors of the service they attend. On the other hand, the
majority of respondents indicated the service doctors as the
source from which they would like to be informed. The top-
ics of greatest interest were, in order, the importance of vac-
cination against COVID, its side effects and, to a much
lesser extent, the possibly serious adverse reactions to
vaccines.
Despite these aspects, the Italian SerD could represent an
excellent vaccination opportunity for a population that would
otherwise be difficult to reach outside the usual healthcare
context.28,29 The presence of multi-professional teams, the
possibility of carrying out and storing blood samples, and the
past experience of targeted vaccination campaigns, candi-
date Italian addiction clinics for a leading role in the contain-
ment of the spread of COVID among drug addicts in Italy, as
was the case for anti-hepatitis vaccinations.28–30
This opportunity should not be considered exhausted
with the attainment, hopefully in the immediate future, of
herd immunity. As reported above, the issues with respect
to the persistence of valid antibody coverage, with the nec-
essary serological checks and any recalls, in addition to the
possible emergence of new variants resistant to common
vaccines, see new importance given to the role of SerDs in
delivering healthcare in a general sense among this disad-
vantaged population.
Equity of access to interventions to prevent, diagnose
and treat COVID-19 means ensuring that vaccines are
accessible and available free of charge to everyone every-
where, especially to those who are under-served and at
increased risk of adverse health outcomes.30 Given strong
peer networks, high coverage of treatment and harm reduc-
tion interventions, and the availability of other access
points which could serve as settings for COVID-19 immu-
nization and/or points of contact for vaccine education and
referral, Italy is well positioned to ensure DUs attending
SerD are not left behind.
The faster we adapt, the better our long-term prospects
will be. We must stop the evolution and spread of more
virulent virus strains now, but we must also be prepared for
the future. It is therefore critical to support public health
policies with strict control measures in order to protect our
healthcare systems, our individual wellbeing, and, in other
words, our future. Leaving no one behind.
Author contributions
ED, LS, LZ, FL, were responsible for the study concept and
design. GICS, SC contributed to the data acquisition. LZ, assisted
with the data analysis and interpretation of findings. ED, FL, FF
drafted the manuscript. All authors critically reviewed the con-
tent and approved the final version of the manuscript for
publication.
Declaration of conflicting interests
The author(s) declared no potential conflicts of interest with
respect to the research, authorship, and/or publication of this
article.
Funding
The author(s) received no financial support for the research,
authorship, and/or publication of this article.
Limitations of the study
Given the above, this work presents a few limitations:
– no power analysis to estimate the necessary sample size was
carried out;
– no standardized questionnaires were used.
Significance for public health
Addiction is a common health problem. In Italy there are more
than 550 SerD (Dependency Services), with 128.000 patients.
This number is not unimportant and COVID-19 vaccination
could increase the quality of life of these patients.
Compulsory declarations
Verona-Trento-Rovigo ethics committee, approve this study,
protocol number 2822CESC.
6 Journal of Public Health Research
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