Influenza In Italy Research Articles

Assessment of Epidemiological Trend of Influenza-Like Illness in Italy from 2010/2011 to 2023/2024 Season: Key Points to Optimize Future Vaccination Strategies against Influenza.

Seasonal influenza is an acute respiratory infectious disease due to influenza viruses, causing a relevant number of illnesses and deaths each year worldwide. Influenza is a preventable disease by vaccination. The aim of this study was to assess the epidemiology of seasonal influenza in Italy through the analysis of data from the epidemiological and virological RespiVirNet surveillance system for the season 2010/2011 to 2023/2024 to identify the epidemiological key points to plan the most appropriate vaccination strategies. The cumulative and maximum weekly incidence of influenza-like illness (ILI) and epidemic period (beginning, end, duration in weeks) were assessed in the pre-pandemic period (2010/2011-2019/2020) and they were compared to the pandemic and post-pandemic one. In all seasons, children reported the highest incidence values of ILI and longer epidemic periods in contrast with the older population. The epidemic seasons 2020/2021 and 2021/2022 had abnormal trends while in the last seasons 2022/2023 and 2023/2024 the epidemiological and virological trends of ILI were confirmed as reported in the pre-pandemic period but with high intensity. Influenza virus A was predominant: the H3N2 subtype circulated more than virus H1N1pdm09. In the few seasons when influenza virus B was the most frequent influenza agent, it co-circulated with influenza virus A. The monitoring of cases is the fundamental tool to better understand the epidemiology of influenza and to optimize future preventive strategies.

Excess hospitalizations and in-hospital mortality associated with seasonal influenza in Italy: a 11-year retrospective study

BackgroundInfluenza and flu-like syndromes are difficult to monitor because the symptoms are not specific, laboratory tests are not routinely performed, and diagnosis codes are often lacking or incompletely registered in medical records. This may result in an underestimation of hospital admissions, associated costs, and in-hospital mortality. Therefore, this study aimed to estimate the public health and economic burden of hospitalisations associated with influenza in Italy, at the national and regional levels.MethodsThis 11-year retrospective study included patients admitted to hospitals for influenza or diagnoses associated with influenza (including respiratory and cardiocirculatory conditions) from 2008/09 to 2018/19. Data on hospitalisations were extracted from the Italian Hospital Discharge Records. Information on weekly influenza-like syndrome incidence and weekly average temperature were used to estimate the burden of influenza in terms of hospital admissions in every Italian region and for different age groups by applying a negative binomial model. The model was also applied to estimate in-hospital mortality and the total costs of influenza and influenza-like hospital admissions.ResultsOver the study period, in addition to 3,970 average seasonal admissions coded as influenza, we estimated an average of 21,500 excess hospitalization associated with influenza per season, which corresponds to 36.4 cases per 100,000. Most of the excess hospitalisations concerned older individuals (> 65 years) and children (0–4 years) with 86 and 125 cases per 100,000, respectively. Large variations were observed across regions. Overall, the total estimated hospital burden associated with influenza (including respiratory and cardiocirculatory conditions) was approximately €123 m per year. While the in-hospital mortality for admissions with a primary diagnosis of influenza was very low (~ 150 cases per season), cases increased dramatically for primary diagnoses of influenza and pneumonia (about 9,500 cases per season). The average seasonal in-hospital deaths attributable to influenza were equal to 2,775 cases.ConclusionsOur findings suggest a remarkable underestimation of the burden of influenza, mostly in the older population but not neglectable in younger individuals. Our results may aid the management of current and future flu seasons and should be used for policy making (e.g., vaccine strategies) and operation management choices (e.g., planning and staffing beds during influenza peaks). Overall, the present study supports the need for increased testing for influenza in Italy to tackle the current underestimation of influenza burden.

The FLURESP European commission project: cost-effectiveness assessment of ten public health measures against influenza in Italy: is there an interest in COVID-19 pandemic?

BackgroundThe FLURESP project is a public health research funded by the European Commission, with the objective to design a methodological framework to assess the cost-effectiveness of existing public health measures against human influenza pandemics. A dataset has been specifically collected in the frame of the Italian health system. As most of interventions against human influenza are relavant against other respiratory diseases pandemics, potential interests in COVID-19 are discussed.MethodsTen public health measures against human influenza pandemics pandemic were selected to be also relevant to other respiratory virus pandemics such as COVID 19: individual (hand washing, using masks), border control (quarantine, fever screening, border closure), community infection (school closure, class dismissal, social distancing, limitation of public transport), reduction of secondary infections (implementation of antibiotic therapy guidelines), pneumococcal vaccination for at-risk people, development of Intensive Care Unit (ICU) capacity, implementation of life support equipments in ICU, screening interventions, vaccination programs targeting health professional and targeting general population.ResultsUsing mortality reduction as effectiveness criteria, the most cost-effective strategies are “reduction of secondary infections” and “implementation of life support equipment in ICU”. The least cost-effective option whatever the level of pandemic events are screening interventions and mass vaccination.ConclusionsA number of intervention strategies against human influenza pandemics appears relevant against every respiratory virus, including the COVID-19 event. Measures against pandemics should be considered according to their expected effectiveness but also their costs for the society because they impose substantial burden to the population, confirming the interest of considering cost-effectiveness of public health measures to enlighten decision making.

Characterizing the transmission patterns of seasonal influenza in Italy: lessons from the last decade

BackgroundDespite thousands of influenza cases annually recorded by surveillance systems around the globe, estimating the transmission patterns of seasonal influenza is challenging.MethodsWe develop an age-structured mathematical model to influenza transmission to analyze ten consecutive seasons (from 2010 to 2011 to 2019–2020) of influenza epidemiological and virological data reported to the Italian surveillance system.ResultsWe estimate that 18.4–29.3% of influenza infections are detected by the surveillance system. Influenza infection attack rate varied between 12.7 and 30.5% and is generally larger for seasons characterized by the circulation of A/H3N2 and/or B types/subtypes. Individuals aged 14 years or less are the most affected age-segment of the population, with A viruses especially affecting children aged 0–4 years. For all influenza types/subtypes, the mean effective reproduction number is estimated to be generally in the range 1.09–1.33 (9 out of 10 seasons) and never exceeding 1.41. The age-specific susceptibility to infection appears to be a type/subtype-specific feature.ConclusionsThe results presented in this study provide insights on type/subtype-specific transmission patterns of seasonal influenza that could be instrumental to fine-tune immunization strategies and non-pharmaceutical interventions aimed at limiting seasonal influenza spread and burden.

The burden of seasonal influenza in Italy: A systematic review of influenza-related complications, hospitalizations, and mortality.

Reliable country‐specific data on influenza burden play a crucial role in informing prevention and control measures. Our purpose was to provide a comprehensive summary of the available evidence on the burden of seasonal influenza in Italy. We performed a systematic literature review of articles published until July 31, 2020. PubMed, Embase, and Web of Science were searched using terms related to burden, influenza, and Italian population. We included studies investigating seasonal influenza‐related complications, hospitalizations, and/or mortality. Sixteen studies were included: eight (50%) analyzed influenza‐related complications, eight (50%) hospitalizations, and seven (43.8%) influenza‐related deaths. Only three studies (19.7%) concerned pediatric age. The synthesis of results showed that patients with chronic conditions have an increased risk for complications up to almost three times as compared with healthy people. Hospitalizations due to influenza can occur in as much as 5% of infected people depending on the study setting. Excess deaths rates were over sixfold higher in the elderly as compared with the rest of population. Although there are still gaps in existing data, there is evidence of the significant burden that influenza places each year especially on high‐risk groups. These data should be used to inform public health decision‐making.

Outbreaks of Equine Influenza in Italy during 2019

Outbreaks of Equine Influenza in Italy during 2019

Pandemics and regional economic growth: evidence from the Great Influenza in Italy

Abstract We investigate the link between the 1918 Great Influenza and regional economic growth in Italy, a country in which the measures implemented by public authorities to contain the contagion were limited or ineffective. The pandemic caused 600,000 deaths in Italy: 1.2% of the population. Going from regions with the lowest mortality to those with the highest mortality is associated to a decline in per capita GDP growth of 6.5%, which dissipated within 3 years. Our estimates provide an upper bound of the adverse effect of pandemics on regional economic growth in the absence of non-pharmaceutical public-health interventions.

Elderly people: propensity to be vaccinated for seasonal influenza in Italy

ABSTRACT Seasonal influenza continues to be a major cause of illness and death. Vaccination is the most cost-effective prophylaxis to prevent the disease and it is particularly important for people who are at high risk of serious complications derived from influenza, especially for people ≥65 years. In Italy, the influenza vaccination program has been unsuccessful with low rates of uptake in people ≥65 years. We analyzed all the community ≥65 years of the Health Promoting Agency (HPA) of Brescia (northern Italy) to evaluate the propensity attitudes toward influenza vaccination among people ≥65 years in four consecutive seasonal influenza campaigns (from 2014/2015 to 2017/2018). Information about subjects were retrieved from administrative databases. Data from 952,822 records were analyzed. The prevalence of vaccinated subjects in the four campaigns was 38.6%, 33.7%, 37.7%, and 40.1%, respectively. Among vaccinated people, the frequencies of individuals aged 65–69.9 years were lower than the frequencies of those in the other age classes, with highest frequencies of vaccinated people in the 75–79.9 years age-class. Overall, males showed a slightly higher propensity to be vaccinated and the propensity toward vaccination increased with age in both genders. Suffering from a chronic disease increased the propensity to vaccination; hypertension had the highest impact on the propensity whereas suffering from vasculopathy has the opposite effect. The value of this study is the possibility to know the factors that might indicate a propensity to get an influenza vaccination and to consider a different approach to people ≥65 years with the characteristics indicating a lower propensity to vaccination.

Case Report of Equine Influenza in Italy, in 2014

Equine influenza (EI) is a highly contagious respiratory disease presently caused by subtype H3N8. As no active surveillance is ongoing in Italy, clinical observations of veterinary practitioners would indicate the infection as endemic. This study reports the isolation and genetic characterization of an EI virus (EIV) from a stable of Thoroughbred race horses. The episode was characterized by fever and dry cough and involved eleven, 2- to 3-year-old, flu vaccinated horses, four of which were found positive for EIV, by reverse-transcriptase real-time polymerase chain reaction (RRT-PCR) targeting the matrix gene. The EIV of two of the four RRT-PCR positive samples was successfully passaged in embryonated chicken eggs. Analysis of amino acid (AA) sequences of hemagglutination (HA) residues detected seven substitutions in the Italian isolate when compared with the prototype strain A/eq/Richmond/1/2007 (H3N8 American lineage, Florida clade 2). The constructed phylogenetic tree locates the present strain within the Florida clade 2, together with viruses isolated between 2011 and 2014 in Algeria, China, Eire, Germany, Japan, Mongolia, and the United Kingdom. Within this cluster, the Italian isolate presents 100% AA identity with A/eq/North Rhine Westphalia/1/2014, responsible of an outbreak in Germany around the same period. Even if vaccinated, only two of the 11 clinically involved animals, different from the EIV-positive animals, reacted positive in HA inhibition. Monitoring of the circulating strains of EIV is essential especially for verifying the appropriateness of the vaccine virus composition, as recommended by the OIE Panel of experts, on the basis of the genetic and antigenic characteristics of emerging strains.

Highly pathogenic H7N7 avian influenza in Italy

Since 1997, there have been several occurrences of low pathogenicity avian influenza (LPAI) H5 and H7 viruses in Italy. Furthermore, H5N2 and H7N1 highly pathogenic (HP) AI viruses were responsible...

Understanding the dynamics of seasonal influenza in Italy: incidence, transmissibility and population susceptibility in a 9-year period.

Objectives: Influenza surveillance systems have been established in many countries in the world, yielding timely information about the intensity and features of seasonal outbreaks. Such data have also been used to estimate epidemiological parameters and to evaluate the effect of factors on infection dynamics. However, little is known about the extent of under‐reporting in surveillance data, and thus of the true influenza incidence in the population. Design: Through mathematical and statistical modelling, we analysed Italian epidemiological and virological surveillance data collected together with serological data derived from influenza vaccine clinical trials performed in Italy. Results: Depending on the season, the reporting rate estimates ranged between 20% and 33% of the total incidence with higher reporting rates in seasons dominated by A/H3N2 virus. Despite a generally higher number of individuals immune against A/H3N2 viruses, effective reproduction ratios were quite similar in all seasons varying between 1·2 and 1·4. We observed an age‐dependent transmissibility for different subtypes: susceptible children were more likely than susceptible adults and elderly to get infected when A/H1N1 or B strains were circulating, while no clear age‐dependence was found for A/H3N2. We also perform sensitivity analysis under different assumptions for vaccine effectiveness, generation time (GT) and model variants; we found that the overall results in predicted patterns were extremely similar, with a slightly better fit obtained with shorter GTs. Conclusions: Our results provide relevant information on the influenza dynamics to fine‐tune intervention strategies and for data collection improvement.

Parental perception of influenza in Italy: A web survey

Parental perception of influenza in Italy: A web survey

The effects of control measures on the economic burden associated with epidemics of avian influenza in Italy

In 1999, Italy experienced a devastating epidemic of high-pathogenicity avian influenza (HPAI) caused by an H7N1 virus subtype. After this epidemic, a ministerial decree was passed to implement control measures for low-pathogenicity avian influenza (LPAI) due to H5 and H7 subtypes. We investigated whether these control measures have decreased the public expenditure associated with epidemics of LPAI and HPAI by comparing the direct and consequential losses of the 1999 epidemic to the losses associated with successive epidemics. The estimated total economic burden of the epidemics was about euro650 million (euro217 million in direct losses and euro433 million in consequential losses). The 1999 epidemic accounted for most of these losses (euro507 million: euro112 million in direct losses and euro395 million in consequential losses), whereas the total economic burden for the 5 successive LPAI was euro143 million (euro105 million in direct losses and euro38 million in consequential losses). These results demonstrate that the implementation of a coordinated set of disease-control measures, which included both emergency and prophylactic vaccination, was able to reduce the overall costs associated with avian influenza epidemics. The results also show that the application of adequate LPAI control measures may limit the risk of emergence of an HPAI virus in an area with a high poultry density, allowing the complete disruption of the poultry market and its huge associated costs to be avoided.

Outbreaks of Classical Swine Influenza in Italy in 1976

Summary Confirmation was obtained of the occurrence in Italy in 1976 of an epizootic of classical swine influenza in pigs. Confirmation was based on the isolation of influenza virus strains showing a close antigenic relationship with both classical influenza A/Swine/ Iowa/30 (Hsw 1 N1) virus and A / New Jersey / 8 / 76 virus; a rise in antibody titer in sera obtained during the acute and convalescent stages of illness; and a high incidence of HI antibodies in tests with A / New Jersey virus (Hsw 1 N1) and a very low incidence in tests with influenza A/Victoria/3/75 (H3 N2) virus on 1330 sera from 46 farms in the province of Mantova (North Italy). Zusammenfassung Bericht uber das Auftreten klassischer Schweineinfluenza in Italien im Jahre 1976 Das epizootische Auftreten klassischer Schweineinfluenza in Schweinen wurde in Italien bestatigt. Diese Bestatigung basiert auf den folgenden Ergebnissen: a) Isolierung von Influenzastammen mit naher antigenetischer Verwandtschaft zu den klassischen Influenzastammen A/Swine/Iowa/30 (HSwl/ N1) und A / New Jersey J 8 / 76. b) Anstieg der Antikorpertiter in Schweineseren wahrend der akuten Krankheitsphase und in der Konvaleszenzphase. c) Haufiger Nachweis von Antikorpern im HAH-Test gegen das A / New Jersey-Virus (HSw1/N1) sowie sehr seltener Nachweis von Antikorpern gegen Influenza A/Victoria/3/75 (H3/N2) in 1330 Seren von 46 Farmen der Provinz Mantua/Norditalien.

An Electronic Learning Course on Avian Influenza in Italy (2008)

An Electronic Learning Course on Avian Influenza in Italy (2008)

Low Pathogenicity Avian Influenza in Italy During 2007 and 2008: Epidemiology and Control

Since 1999, the Italian poultry production system has experienced several outbreaks of avian influenza (AI), mainly located in northeastern Italy. This paper describes the low pathogenicity (LP) AI outbreaks detected during the surveillance activities implemented in 2007-08. From May to October 2007, ten rural and hobby poultry farms were infected by an LPAI virus of the H7N3 subtype. In August-October 2007, the H7N3 LPAI virus was introduced into the industrial poultry sector with the involvement of six meat turkey farms. Phylogenetic analysis of the hemagglutinin gene indicated that all but one of the H7N3 virus strains had a high level of homology (98.7%-99.8%). Furthermore, in August 2007, an LPAI H5N2 virus was identified in a free-range geese and duck breeder flock. The hemagglutinin and neuraminidase genes showed a high level of homology (99.8% and 99.9%, respectively) with H5N2 LPAI viruses isolated from mallards in July 2007 in the same area, suggesting a possible introduction from the wild reservoir. All the birds (in total 129,386) on the infected poultry farms were culled. The prompt implementation of AI control measures, including the enforcement of a targeted emergency vaccination plan, allowed the rapid eradication of infection. In 2008, three LPAI viruses (two H7N1 and one H5N1) were identified in dealer/rural farms. The surveillance activity implemented in this area allowed the prompt detection of LPAI viruses of the H5 and H7 subtypes in the rural sector, which, as observed in the 2007 epidemic, might be the source of infection for industrial poultry.

An Electronic Learning Course on Avian Influenza in Italy (2008)

The success of emergency intervention to control contagious animal diseases is dependent on the preparedness of veterinary services. In the framework of avian influenza preparedness, the Italian Ministry of Health, in cooperation with the National Reference Centers for Epidemiology and Avian Influenza, implemented an electronic learning course using new web-based information and communication technologies. The course was designed to train veterinary officers involved in disease outbreak management, laboratory diagnosis, and policy making. The "blended learning model" was applied, involving participants in tutor-supported self-learning, collaborative learning activities, and virtual classes. The course duration was 16 hr spread over a 4-wk period. Six editions were implemented for 705 participants. All participants completed the evaluation assignments, and the drop out rate was very low (only 4%). This project increased the number of professionals receiving high-quality training on AI in Italy, while reducing expenditure and maximizing return on effort.

Low Pathogenicity Avian Influenza in Italy During 2007 and 2008: Epidemiology and Control

Low Pathogenicity Avian Influenza in Italy During 2007 and 2008: Epidemiology and Control

Vaccination as a tool to combat introductions of notifiable avian influenza viruses in Europe, 2000 to 2006

In late 2000, Italy was the first country of the European Union (EU) to implement an emergency vaccination programme against notifiable avian influenza. Vaccination with a conventional vaccine containing a seed strain with a different neuraminidase subtype from that of the field virus was used to complement biosecurity and restriction measures as part of an overall eradication strategy. This vaccination technique, in line with the Differentiating Infected from Vaccinated Animals system (DIVA), was applied several times until March 2008. This strategy enabled the identification of field exposed flocks and ultimately the eradication of low pathogenic H7N1, H7N3 and H5N2 infections. Italy was also the first country to implement a bivalent H5/H7 prophylactic vaccination programme of defined poultry populations, which was discontinued in December 2006. Following the incursion of highly pathogenic H5N1 into Europe, in 2005 and 2006, two other EU Member States, namely France and the Netherlands, implemented preventive vaccination programmes in 2006 but they targeted selected poultry populations different from those targeted in Italy and were implemented for short periods of time. Data generated during six years of experience with vaccination against avian influenza in Italy indicate that it is a useful tool to limit secondary spread and possibly prevent the introduction of low pathogenic avian influenza viruses in a susceptible population. The experience of France and the Netherlands provides data on vaccination of ducks and hobby poultry respectively and monitoring programmes associated with vaccination and difficulties related to their application. The advantages and disadvantages of vaccination need to be considered in the decision-making process, including the financial aspects of vaccination.

Mitigation Measures for Pandemic Influenza in Italy: An Individual Based Model Considering Different Scenarios

BackgroundIndividual-based models can provide the most reliable estimates of the spread of infectious diseases. In the present study, we evaluated the diffusion of pandemic influenza in Italy and the impact of various control measures, coupling a global SEIR model for importation of cases with an individual based model (IBM) describing the Italian epidemic.Methodology/Principal FindingsWe co-located the Italian population (57 million inhabitants) to households, schools and workplaces and we assigned travel destinations to match the 2001 census data. We considered different R0 values (1.4; 1.7; 2), evaluating the impact of control measures (vaccination, antiviral prophylaxis -AVP-, international air travel restrictions and increased social distancing). The administration of two vaccine doses was considered, assuming that first dose would be administered 1-6 months after the first world case, and different values for vaccine effectiveness (VE). With no interventions, importation would occur 37–77 days after the first world case. Air travel restrictions would delay the importation of the pandemic by 7–37 days. With an R0 of 1.4 or 1.7, the use of combined measures would reduce clinical attack rates (AR) from 21–31% to 0.3–4%. Assuming an R0 of 2, the AR would decrease from 38% to 8%, yet only if vaccination were started within 2 months of the first world case, in combination with a 90% reduction in international air traffic, closure of schools/workplaces for 4 weeks and AVP of household and school/work close contacts of clinical cases. Varying VE would not substantially affect the results.ConclusionsThis IBM, which is based on country-specific demographic data, could be suitable for the real-time evaluation of measures to be undertaken in the event of the emergence of a new pandemic influenza virus. All preventive measures considered should be implemented to mitigate the pandemic.