Safety of heterologous ChAdOx1-S/BNT162b2 primary schedule versus homologous BNT162b2 vaccination: Insights from an Italian post-marketing study, 2021.

During COVID-19 vaccination campaign, possible ChAdOx1-S-associated risks of thrombosis with thrombocytopenia syndrome led to implement ChAdOx1-S/BNT162b2 heterologous vaccination, despite the limited information on its reactogenicity and safety. We conducted a prospective observational post-marketing surveillance study to assess the safety of this heterologous schedule. A casually selected sample of recipients (n: 85; age: 18-60 years) of ChAdOx1-S/BNT162b2 at the vaccination hub of the Foggia Hospital, Italy, was matched with an equal sample of recipients of homologous BNT162b2. Safety was evaluated 7 days, 1 month and 14 weeks after the primary vaccination series using an adapted version of the "V-safe active surveillance for COVID-19 vaccine safety" CDC standardized questionnaire. After 7 days, local reactions were highly frequent (>80%) in both groups, and systemic reactions were less common (<70%). Moderate or severe pain at the injection site (OR = 3.62; 95%CI, 1.45-9.33), moderate/severe fatigue (OR = 3.40; 95%CI, 1.22-9.49), moderate/severe headache (OR = 4.72; 95%CI, 1.37-16.23), intake of antipyretics (OR = 3.05; 95 CI%, 1.35-6.88), inability to perform daily activities and work (OR = 2.64; 95%CI, 1.24-5.62) were significantly more common with heterologous than homologous vaccination. No significant difference in self-reported health status was recorded 1 month or 14 weeks after the second dose with BNT162b2 or ChAdOx1-S/BNT162b2. Our study confirms the safety of both heterologous and homologous vaccination, with a slight increase in some short-term adverse events for the heterologous regimen. Therefore, administering a second dose of a mRNA vaccine to the recipients of a previous dose of viral vector vaccine may have represented an advantageous strategy to improve flexibility and to accelerate the vaccination campaign.

Hospital admission and mortality rates for non-Covid diseases among residents of the long-term care facilities before and during the pandemic: a cohort study in two Italian regions.

Aim: Long-term-care facility residents are a vulnerable population who experienced reduced healthcare access during the pandemic. This study aimed to assess the indirect impact of the COVID-19 pandemic, in terms of hospitalisation and mortality rates, among this population in two Italian Regions, Tuscany and Apulia, during 2020 in comparison with the pre-pandemic period. Subject and methods: We conducted a retrospective cohort study on people residing in long-term-care facilities from 1 January 2018 to 31 December 2020 (baseline period: 1 January 2018-8 March 2020; pandemic period: and 9 March-31 December 2020). Hospitalisation rates were stratified by sex and major disease groups. Standardised weekly rates were estimated with a Poisson regression model. Only for Tuscany, mortality risk at 30 days after hospitalisation was calculated with the Kaplan-Meier estimator. Mortality risk ratios were calculated using Cox proportional regression models. Results: Nineteen thousand two hundred and fifty individuals spent at least 7 days in a long-term-care facility during the study period. The overall mean non-Covid hospital admission rate per 100 000 residents/week was 144.1 and 116.2 during the baseline and pandemic periods, with a decrease to 99.7 and 77.3 during the first (March-May) and second lockdown (November-December). Hospitalisation rates decreased for all major disease groups. Thirty-day mortality risk ratios for non-Covid conditions increased during the pandemic period (1.2, 1.1 to 1.4) compared with baseline. Conclusion: The pandemic resulted in worse non-COVID-related health outcomes for long-term-care facilities' residents. There is a need to prioritise these facilities in national pandemic preparedness plans and to ensure their full integration in national surveillance systems. Supplementary information: The online version contains supplementary material available at 10.1007/s10389-023-01925-1.

Association of socio-economic deprivation with COVID-19 incidence and fatality during the first wave of the pandemic in Italy: lessons learned from a local register-based study.

BACKGROUND: COVID-19 has been characterised by its global and rapid spread, with high infection, hospitalisation, and mortality rates worldwide. However, the course of the pandemic showed differences in chronology and intensity in different geographical areas and countries, probably due to a multitude of factors. Among these, socio-economic deprivation has been supposed to play a substantial role, although available evidence is not fully in agreement. Our study aimed to assess incidence and fatality rates of COVID-19 across the levels of socio-economic deprivation during the first epidemic wave (March-May 2020) in the Italian Province of Foggia, Apulia Region. METHODS: Based on the data of the regional active surveillance platform, we performed a retrospective epidemiological study among all COVID-19 confirmed cases that occurred in the Apulian District of Foggia, Italy, from March 1st to May 5th, 2020. Geocoded addresses were linked to the individual Census Tract (CT) of residence. Effects of socio-economic condition were calculated by means of the Socio-Economic and Health-related Deprivation Index (SEHDI) on COVID-19 incidence and fatality. RESULTS: Of the 1054 confirmed COVID-19 cases, 537 (50.9%) were men, 682 (64.7%) were 0-64 years old, and 338 (32.1%) had pre-existing comorbidities. COVID-19 incidence was higher in the less deprived areas (p < 0.05), independently on age. The level of socio-economic deprivation did not show a significant impact on the vital status, while a higher fatality was observed in male cases (p < 0.001), cases > 65 years (p < 0.001), cases having a connection with a nursing home (p < 0.05) or having at least 1 comorbidity (p < 0.001). On the other hand, a significant protection for healthcare workers was apparent (p < 0.001). CONCLUSIONS: Our findings show that deprivation alone does not affect COVID-19 incidence and fatality burden, suggesting that the burden of disease is driven by a complexity of factors not yet fully understood. Better knowledge is needed to identify subgroups at higher risk and implement effective preventive strategies.

European Cohorts of patients and schools to Advance Response to Epidemics (EuCARE): a cluster randomised interventional and observational study protocol to investigate the relationship between schools and SARS-CoV-2 infection.

BACKGROUND: Contradictory results were reported on the role of school closure/reopening on the overall SARS-CoV-2 transmission rate, as well as on which kind and level of mitigation measures implemented in schools may be effective in limiting its diffusion. Some recent studies were reassuring, showing that opening did not increase the community spread, although teachers and families are worried about the high class density. On the other hand, distance learning was associated with a negative impact on learning, sociability and psychological health, especially in vulnerable children. As it becomes clear that the SARS-CoV-2 pandemic will last for a long time, there is a high need for studies and solutions to support safe schools opening based on scientific evidence of harms and benefits. The Lolli-Methode (LM) is a strategy for epidemiological surveillance and early intervention aiming at SARS-CoV-2 outbreaks' reduction in schools, relying on polymerase chain reaction analysis of saliva samples. METHODS: In this cluster randomised trial protocol, we aim to determine whether the LM is useful to support schools opening and to reduce clusters and attack rates in schools, compared with the standard of care (SoC) surveillance by public health departments. This multicenter study will enrol 440 classes (around 8800 students, teachers and other personnel) from two countries, cluster randomised to LM or SoC. The samples from the pools will be collected and tested using PCR-based techniques. Test results will be combined with questionnaires filled in by children, parents, schoolteachers, and principals, concerning ongoing mitigation measures, their perceived psychological impact and other health and socio-economic information. An ancillary observational study will be carried out to study the prevalence of SARS-CoV-2 in schools, frequencies and size of clusters and attack rates, to compare the effectiveness of the different preventive measures adopted and to evaluate psychological issues in students and teachers in relation to the pandemic's containment measures. DISCUSSION: By the end of this study, we will have defined and characterised the applicability of the LM for SARS-CoV-2 surveillance, as well as the impact of pandemic preventive measures on children and teachers. Trial registration International Standard Randomised Controlled Trial Number: NCT05396040, 27.05.2022.

Covid-19 vaccination programme effectiveness against SARS-CoV-2 related infections, hospital admissions and deaths in the Apulia region of Italy: a one-year retrospective cohort study.

Studies reporting vaccine effectiveness against COVID-19 outcomes concentrate mainly on estimates of one single type of vaccine and variant, seldom considering waning effects. We aimed to estimate the effectiveness of the overall COVID-19 vaccination programme implemented in the Apulia region of Italy at preventing SARS-CoV-2 infections, COVID-19-related hospital admissions and deaths during alpha and delta variant dominant periods. We conducted a retrospective cohort study using electronic health records of persons 16 years and older resident in the Apulia region, assessing the effectiveness of the combined use of BNT162b2, mRNA-1273, ChAdOx1-S and Ad26.COV2.S vaccines against confirmed COVID-19 infections, hospitalisations and deaths, for fully and partially vaccinated persons as well as by time since vaccination and variants. Cox regression models yielding hazard ratios were used to calculate the overall vaccination programme effectiveness. From 1 January to 1 December 2021, we included 3,530,967 eligible persons in the cohort, of whom 2,770,299 were fully vaccinated and 158,313 were COVID-19 positive at the end of the study period. The effectiveness of the programme over the entire study period for fully vaccinated persons against COVID-19 infection, hospitalisation and death were 87.69% (CI95% 87.73-88.18), 94.08% (93.58-94.54) and 95.95% (CI95% 95.26-96.54), respectively. The effectiveness against COVID-19 infection of fully vaccinated subjects during the alpha and delta period was respectively 88.20% (CI95% 87.60-99.78) and 59.31% (CI95% 57.91-60.67), against hospitalisation 93.89% (CI95% 92.67-94.90) and 88.32% (CI95% 86.50-89.90) and against death 93.83% (CI95% 91.65-95.45) and 85.91 (CI95% 79.98-90.09). The waning effects of the programme regarding COVID-19 infection during the delta period were stronger than for alpha, with 75.85% (CI95% 74.38-77.24) effectiveness after 1-2 months and 8.35% (CI95% 3.45-13.01) after 5-6 months after full vaccination. The effectiveness against hospitalisation and death during the delta period waned rapidly and at 7-8-months after the full vaccination respectively decreased to 27.67% (CI95% 7.48-43.45) and 48.47 (CI95% 53.97-34.82). Our study suggests that the COVID-19 vaccination program in Apulia was strongly protective against COVID-19 infection, hospitalisation, and death due to alpha as well as delta variants, although its effectiveness is reduced over time.

Estimating the Proportion of Asymptomatic COVID-19 Cases in an Italian Region with Intermediate Incidence during the First Pandemic Wave: An Observational Retrospective Study.

Early in the COVID-19 pandemic, asymptomatic transmission represented an important challenge for controlling the spread of SARS-CoV-2 through the traditional public health strategies. Further understanding of the contribution of asymptomatic infections to SARS-CoV-2 transmission has been of crucial importance for pandemic control. We conducted a retrospective epidemiological study to characterize asymptomatic COVID-19 cases occurred in the Apulia region, Italy, during the first epidemic wave of COVID-19 outbreak (February 29-July 7, 2020). We analyzed data collected in a regional platform developed to manage surveillance activities, namely, investigation and follow-up of cases and contacts, contact tracing, and laboratory and clinical data collection. We included all asymptomatic cases that were laboratory-confirmed during the appropriate follow-up, defined as persons infected with SARS-CoV-2 who did not develop symptoms/clinical signs of the disease. Between February 29 and July 7, 2020, a total of 4,536 cases were diagnosed with COVID-19 among 193,757 tests performed. The group of persons with asymptomatic SARS-CoV-2 infection consisted of 903 cases; the asymptomatic proportion was 19.9% (95% CI: 18.8-21.1%); this decreased with increasing age (OR: 0.89, 95% CI: 0.83-0.96; p = 0.001), in individuals with underlying comorbidities (OR: 0.55, 95% CI: 0.41-0.73; p < 0.001), and in males (OR: 0.69, 95% CI: 0.54-0.87; p = 0.002). The median asymptomatic SARS-CoV-2 RNA positive period was 19 days (IQR: 14-31) and the cumulative proportion of persons with resolution of infection 14 days after the first positive PCR test was 74%. As the public health community is debating the question of whether asymptomatic and late spreaders could sustain virus transmission in the communities, such cases present unique opportunities to gain insight into SARS-CoV-2 adaptation to human host. This has important implications for future COVID-19 surveillance and prevention.

Self-reported olfactory and gustatory dysfunctions in COVID-19 patients: a 1-year follow-up study in Foggia district, Italy.

BACKGROUND: From the initial stages of the pandemic in early 2020, COVID-19-related olfactory and gustatory dysfunctions have been widely reported and are emerging as one of the most frequent long-term sequelae of SARS-CoV-2 infection. However, data regarding the long-term recovery of the sense of smell and taste are lacking. This study aimed to characterize the evolution up to one year after the diagnosis of self-reported olfactory and gustatory dysfunctions in COVID-19 cases. METHODS: Based on the data of the active surveillance platform of the Apulia region, Italy, we selected the residents of Foggia district who were confirmed positive for SARS-CoV-2 from March 1st to June 16th, 2020, and home-quarantined with paucisymptomatic-to-mild clinical presentation. Self-reported olfactory and gustatory dysfunctions were recorded at baseline through a survey of dichotomous questions. The evolution of these symptoms at approximately one year was prospectively assessed via telephone by the validated sino-nasal outcome test 22 (SNOT-22, Italian version). RESULTS: Among the 1,175 COVID-19 cases notified in the Foggia district during the first epidemic wave, 488 had paucisymptomatic-to-mild clinical presentation. Of these, 41.2% (n = 201, 95% confidence interval [CI] 36.8-45.7%) reported at least one sensory dysfunction. A total of 178 to 201 (88.5%) patients agreed to participate in the follow-up survey. According to the SNOT-22 results, the persistence of a sensory dysfunction was observed in the 29.8% (n = 53, 95% CI 23.2-37.1%) of them. Particularly, loss of smell persisted in 25.8% (n = 46, 95% CI 19.6-32.9%), loss of taste in 21.3% (n = 38, 95% CI 15.6-28.1%), loss of both in 17.4% (n = 31, 95% CI 12.2-23.8%) of participants in the follow-up. The rates of full recovery increased over time: from 59% at 30 days to 71.9% at 90 days for the sense of smell; from 61.3% at 30 days to 74.7% at 90 days for the sense of taste. CONCLUSIONS: The persistence of COVID-19-related olfactory and gustatory dysfunctions up to 12 months after the disease onset in a noteworthy proportion (approximately 3 out of 10) of patients with paucisymptomatic-to-mild clinical presentation deserves further investigations due to its possible pathophysiological implications and impact on the quality of life.

Estimating the Proportion of Asymptomatic COVID-19 Cases in an Italian Region with Intermediate Incidence during the First Pandemic Wave: An Observational Retrospective Study

Early in the COVID-19 pandemic, asymptomatic transmission represented an important challenge for controlling the spread of SARS-CoV-2 through the traditional public health strategies. Further understanding of the contribution of asymptomatic infections to SARS-CoV-2 transmission has been of crucial importance for pandemic control. We conducted a retrospective epidemiological study to characterize asymptomatic COVID-19 cases occurred in the Apulia region, Italy, during the first epidemic wave of COVID-19 outbreak (February 29-July 7, 2020). We analyzed data collected in a regional platform developed to manage surveillance activities, namely, investigation and follow-up of cases and contacts, contact tracing, and laboratory and clinical data collection. We included all asymptomatic cases that were laboratory-confirmed during the appropriate follow-up, defined as persons infected with SARS-CoV-2 who did not develop symptoms/clinical signs of the disease. Between February 29 and July 7, 2020, a total of 4,536 cases were diagnosed with COVID-19 among 193,757 tests performed. The group of persons with asymptomatic SARS-CoV-2 infection consisted of 903 cases;the asymptomatic proportion was 19.9% (95% CI: 18.8-21.1%);this decreased with increasing age (OR: 0.89, 95% CI: 0.83-0.96;p = 0.001), in individuals with underlying comorbidities (OR: 0.55, 95% CI: 0.41-0.73;p < 0.001), and in males (OR: 0.69, 95% CI: 0.54-0.87;p = 0.002). The median asymptomatic SARS-CoV-2 RNA positive period was 19 days (IQR: 14-31) and the cumulative proportion of persons with resolution of infection 14 days after the first positive PCR test was 74%. As the public health community is debating the question of whether asymptomatic and late spreaders could sustain virus transmission in the communities, such cases present unique opportunities to gain insight into SARS-CoV-2 adaptation to human host. This has important implications for future COVID-19 surveillance and prevention.

Effect of Previous SARS-CoV-2 Infection on Antibody Response to a Single Immunization with the Pfizer BNT162b mRNA Vaccine Among Healthcare Workers in Foggia, Italy.

INTRODUCTION: Data have suggested that SARS-CoV-2 infection causes an antibody response at least as strong as one BNT162b2 vaccine dose. Nevertheless, some aspects require further investigation to better understand the immunogenicity of one vaccine dose among infected individuals. Thus, we evaluated how previous SARS-CoV-2 infection may influence the humoral immunity after a single Pfizer BNT162b mRNA vaccine dose in a sample of healthcare workers (HCWs). METHODS: As part of the routine surveillance activity conducted among HCWs of the Policlinico Riuniti Foggia Hospital (Apulia region, Italy), we conducted a retrospective serosurvey in the period January-March 2021. We compared specific antibody titres (anti-spike IgGs measured by enzyme-linked immunoassay, ELISA) after SARS-CoV-2 infection and after the first dose of the BNT162b2 vaccine, analysing the impact of sex, age, time since infection, and presence of symptoms on the humoral response. RESULTS: We included in the study 58 HCWs (mean age 44.1 years, 48.2% male) with anti-spike IgG titres available before and after the first BNT162b2 vaccine dose. Among these, we observed higher titres in previously infected cases (N = 21) than in COVID-19-naïve subjects (N = 37) (medians 1510 vs. 0.68; p < 0.001). A statistically significant difference in anti-spike IgG titres was also observed among previously infected HCWs before vaccine dose in comparison with post-dose infection-naïve HCWs (medians 18.37 vs. 0.68, p < 0.001). Among infected individuals, no differences by sex, age, or time since infection were reported (p > 0.05). Post-dose titres of symptomatic and asymptomatic infected HCWs slightly differed (medians = 1900 vs. 1090; p = 0.048). CONCLUSION: Our data support the viable hypothesis of a single-dose vaccine regimen in individuals with a history of COVID-19, but no conclusion on duration of protection in this group can be drawn from our study.

Uptake of Vaccinations among Children with Chronic Diseases Is Affected by Knowledge Gaps and Implementation Challenges in Italy.

(1) Background: Children with chronic medical conditions may be at increased risk for severe complications related to vaccine-preventable infections. Therefore, additional booster doses or supplementary vaccines are recommended, over and above the routine immunization schedule for healthy children. The aim of this study was to investigate attitude, knowledge, and practices toward additional vaccinations for children affected by chronic conditions among pediatricians and parents. (2) Methods: This study is based on two surveys: (i) a national cross-sectional survey, targeting pediatrician working in hospitals or in the primary health sector; (ii) a local cross-sectional survey, targeting parents of children with a previous diagnosis of chronic disease. (3) Results: Despite the fact that most of the health professionals and parents interviewed had an overall positive vaccine attitude, most pediatricians did not show an adequate knowledge of additional vaccinations for children affected by chronic diseases. Moreover, the coverage of additional recommended vaccinations in chronic pediatric patients was low. (4) Conclusions: This research highlighted important existing challenges hampering optimal vaccination coverage among pediatric chronic patients, including knowledge gaps on tailored vaccination schedules among pediatricians and organizational issues. The ongoing review of the Italian national immunization plan is a not-to-be-missed-opportunity to include evidence-based, detailed, and comprehensive recommendations on vaccinations for children affected by chronic conditions.

Sex and gender differences in COVID-19: an Italian local register-based study.

OBJECTIVES: The present study aimed to explore differences in COVID-19 outcomes between male and female cases in the Apulian District of Foggia, Italy. DESIGN AND SETTING: We performed a retrospective epidemiological study among all COVID-19 confirmed cases that occurred in the Apulian District of Foggia from 29 February to 30 June 2020. The surveillance data from a regional registry (GIAVA-COVID) were used. MAIN OUTCOMES: The main outcome measures were the proportion of hospitalisations, virus clearance and the case fatality rate. RESULTS: A total of 1175 cases (50.7% female; median age: 55 years) were identified among 55 131 tests performed. The proportion of hospitalisation with COVID-19 diagnosis was 45.4% in men versus 37.9% in women (p<0.01), while the average length of stay in hospitals was 31.3±14.6 days in women versus 26.8±14.4 days in men (p<0.01). The proportion of cases who achieved virus clearance was higher in women (84.2%; days to clearance: 28.0±12.1) than in men (79.3%; days to clearance: 29.4±12.9; p<0.05). Men were associated with a significantly higher risk of dying from COVID-19 than women (case fatality rate 16.1% vs 10.4%; p<0.01). The mean time, from diagnosis to death, was 14.5±14.4 days in women compared with 10.6±10.7 days in men (p<0.01). The male sex, age ≥55 years and presence of at least one underlying comorbidity significantly raised the risk of hospitalisation, persistent infection and death (p<0.05). CONCLUSIONS: This study suggests that more attention should be paid to sex as a variable for the interpretation of COVID-19 data. Sex-disaggregated data will help clinicians to make appropriate patient-tailored medical decisions.

Large-scale IgM and IgG SARS-CoV-2 serological screening among healthcare workers with a low infection prevalence based on nasopharyngeal swab tests in an Italian university hospital: Perspectives for public health.

BACKGROUND: Healthcare workers (HCWs) are highly exposed to SARS-CoV-2 infection given their specific tasks. The IgG-IgM serological assay has demonstrated good accuracy in early detection in symptomatic patients, but its role in the diagnosis of asymptomatic patients is uncertain. The aim of our study was to assess IgM and IgG prevalence in sera in a large cohort of HCWs previously subjected to Nasopharyngeal swab test (NST) after accurate risk assessment due to positive COVID-19 patient exposure during an observation period of 90 days. METHODS: 2407 asymptomatic HCWs that had close contact with COVID-19 patients in the period between April 8th and June 7th were screened with NST based on the RT-PCR method. In parallel, they underwent large-scale chemiluminescence immunoassays involving IgM-IgG serological screening to determine actual viral spread in the same cohort. RESULTS: During the 90-day observation period, 18 workers (0.75%) resulted positive for SARS-CoV-2 infection at the NST, whereas the positivity rates for IgM and IgG were 11.51% and 2.37%, respectively (277 workers). Despite high specificity, serological tests were inadequate for detecting SARS-CoV-2 infection in patients with previous positive NST results (IgM and IgG sensitivities of 27.78% and 50.00%, respectively). CONCLUSIONS: These findings indicate a widespread low viral load of SARS-CoV-2 among hospital workers. However, serological screening showed very low sensitivity with respect to NST in identifying infected workers, and negative IgG and IgM results should not exclude the diagnosis of COVID-19. IgG-IgM chemiluminescence immunoassays could increase the diagnosis of COVID-19 only in association with NST, and this association is considered helpful for decision-making regarding returning to work.