Immunization strategies targeting newly arrived migrants in Non-EU countries of the mediterranean basin and black sea

Background: The World Health Organization recommends that host countries ensure appropriate vaccinations to refugees, asylum seekers and migrants. However, information on vaccination strategies targeting migrants in host countries is limited. Methods: In 2015-2016 we carried out a survey among national experts from governmental bodies of 15 non-EU countries of the Mediterranean and Black Sea in order to document and share national vaccination strategies targeting newly arrived migrants. Results: Four countries reported having regulations/procedures supporting the immunization of migrants at national level, one at sub-national level and three only targeting specific population groups. Eight countries offer migrant children all the vaccinations included in their national immunization schedule; three provide only selected vaccinations, mainly measles and polio vaccines. Ten and eight countries also offer selected vaccinations to adolescents and adults respectively. Eight countries provide vaccinations at the community level; seven give priority vaccines in holding centres or at entry sites. Data on administered vaccines are recorded in immunization registries in nine countries. Conclusions: Although differing among countries, indications for immunizing migrants are in place in most of them. However, we cannot infer from our findings whether those strategies are currently functioning and whether barriers to their implementation are being faced. Further studies focusing on these aspects are needed to develop concrete and targeted recommendations for action. Since migrants are moving across countries, development of on-line registries and cooperation between countries could allow keeping track of administered vaccines in order to appropriately plan immunization series and avoid unnecessary vaccinations

Dengue virus infections among European travellers, 2015 to 2019

Background: Dengue is a disease with major impacts on public health in tropical and subtropical countries. In Europe, in the past decade, few autochthonous outbreaks were described. Aim: We aimed to identify factors associated with frequency of dengue virus infection among European travellers and at assessing how surveillance data could support preparedness against autochthonous outbreaks within Europe. Methods: We performed a descriptive analysis of travel-related dengue cases reported by European countries from 2015 through 2019. Using flight passenger data, we calculated travellers’ infection rates (TIR). We investigated the following associations: (i) between TIR and incidence rate in selected countries of infection and (ii) between number of travel-related cases and occurrence of autochthonous outbreaks within Europe. Results: There were 11,478 travel-related dengue cases and the TIR was 2.8 cases per 100,000 travellers. Most cases were infected in Asia (71%), predominantly in south-eastern Asia. The TIR was highest among travellers returning from Asia (6.1/100,000). There was an association between the incidence rate in the country of infection and the TIR but no association between the number of travel-related cases and occurrence of autochthonous outbreaks in Europe. Conclusions: The likelihood of infection in travellers is a function of the ongoing epidemiological situation in the country of exposure. The number of travel-related cases alone is not sufficient to estimate the likelihood of autochthonous outbreaks where vectors are present in Europe. Additional contributing factors such as adequate vectorial capacity and suitable environmental conditions are required.Peer Reviewe

Estimated effectiveness of a primary cycle of protein recombinant vaccine nvx-cov2373 against COVID-19

Importance: Protein recombinant vaccine NVX-CoV2373 (Novavax) against COVID-19 was authorized for its use in adults in late 2021, but evidence on its estimated effectiveness in a general population is lacking. Objective: To estimate vaccine effectiveness of a primary cycle with NVX-CoV2373 against SARS-CoV-2 infection and symptomatic COVID-19. Design, setting, and participants: Retrospective cohort study linking data from the national vaccination registry and the COVID-19 surveillance system in Italy during a period of Omicron predominance. All adults starting a primary vaccination with NVX-CoV2373 between February 28 and September 4, 2022, were included, with follow-up ending on September 25, 2022. Data were analyzed in February 2023. Exposures: Partial (1 dose only) vaccination and full vaccination (2 doses) with NVX-CoV-2373. Main outcomes and measures: Notified SARS-CoV-2 infection and symptomatic COVID-19. Poisson regression models were used to estimate effectiveness against both outcomes. Adjusted estimated vaccine effectiveness was calculated as (1 - incidence rate ratio) × 100. Results: The study included 20 903 individuals who started the primary cycle during the study period. Median (IQR) age of participants was 52 (39-61) years, 10 794 (51.6%) were female, and 20 592 participants (98.5%) had no factors associated with risk for severe COVID-19. Adjusted estimated vaccine effectiveness against notified SARS-CoV-2 infection in those partially vaccinated with NVX-CoV2373 was 23% (95% CI, 13%-33%) and was 31% (95% CI, 22%-39%) in those fully vaccinated. Estimated vaccine effectiveness against symptomatic COVID-19 was 31% (95% CI, 16%-44%) in those partially vaccinated and 50% (95% CI, 40%-58%) in those fully vaccinated. Estimated effectiveness during the first 4 months after completion of the primary cycle decreased against SARS-CoV-2 infection but remained stable against symptomatic COVID-19. Conclusions and relevance: This cohort study found that, in an Omicron-dominant period, protein recombinant vaccine NVX-CoV2373 was associated with protection against SARS-CoV-2 infection and symptomatic COVID-19. The use of this vaccine could remain an important element in reducing the impact of the SARS-CoV-2 pandemic

A population-based cohort approach to assess excess mortality due to the spread of COVID-19 in Italy, January-May 2020

Aims: To assess the impact of the COVID-19 pandemic on all-cause mortality in Italy during the first wave of the epidemic, taking into consideration the geographical heterogeneity of the spread of COVID-19. Methods: This study is a retrospective, population-based cohort study using national statistics throughout Italy. Survival analysis was applied to data aggregated by day of death, age groups, sex, and Italian administrative units (107 provinces). We applied Cox models to estimate the relative hazards (RH) of excess mortality, comparing all-cause deaths in 2020 with the expected deaths from all causes in the same time period. The RH of excess deaths was estimated in areas with a high, moderate, and low spread of COVID-19. We reported the estimate also restricting the analysis to the period of March-April 2020 (first peak of the epidemic). Results: The study population consisted of 57,204,501 individuals living in Italy as of January 1, 2020. The number of excess deaths was 36,445, which accounts for 13.4% of excess mortalities from all causes during January-May 2020 (i.e., RH = 1.134; 95% confidence interval (CI): 1.129-1.140). In the macro-area with a relatively higher spread of COVID-19 (i.e., incidence rate, IR): 450-1,610 cases per 100,000 residents), the RH of excess deaths was 1.375 (95% CI: 1.364-1.386). In the area with a relatively moderate spread of COVID-19 (i.e., IR: 150-449 cases) it was 1.049 (95% CI: 1.038-1.060). In the area with a relatively lower spread of COVID-19 (i.e., IR: 30-149 cases), it was 0.967 (95% CI: 0.959-0.976). Between March and April (peak months of the first wave of the epidemic in Italy), we estimated an excess mortality from all causes of 43.5%. The RH of all-cause mortality for increments of 500 cases per 100,000 residents was 1.352 (95% CI: 1.346-1.359), corresponding to an increase of about 35%. Conclusions: Our analysis, making use of a population-based cohort model, estimated all-cause excess mortality in Italy taking account of both time period and of COVID-19 geographical spread. The study highlights the importance of a temporal/geographic framework in analyzing the risk of COVID-19-epidemy related mortality

Genotyping of circulating measles strains in Italy in 2010

Introduction. The European Regional Office of the World Health Organization developed a strategic approach to stop the indigenous transmission of measles in its 53 Member States by 2015. In Italy, laboratory surveillance activity is implemented by the National Reference Laboratory for Measles and Rubella at the Italian National Institute of Health (Istituto Superiore di Sanità, Rome). The role of the National Reference Laboratory is to strengthen surveillance systems through rigorous case investigation and laboratory confirmation of suspected sporadic cases and outbreaks. Genetic characterization of wild-type measles virus is an essential component of the laboratory-based surveillance. This study describes the molecular characterization of measles virus strains isolated during 2010. Methods. Dried blood spots, urine and oral fluid samples were collected from patients with a suspected measles infection. Serological tests were performed on capillary blood, and viral detection was performed on urine and oral fluid samples through molecular assay. Positive samples were sequenced and phylogenetically analysed.Results and discussion. The phylogenetic analysis showed a co-circulation of genotypes D4 and D8, and sporadic cases associated to genotypes D9 and B3. Then, molecular epidemiology of measles cases permitted to establish that D4 and D8 were the endemic genotypes in Italy during 2010

Measles in Italy, laboratory surveillance activity during 2010

Introduction. The European Regional Office of the World Health Organization (WHO/Europe) developed a strategic approach to stop the indigenous transmission of measles in its 53 Member States by 2015. This study describes the measles laboratory surveillance activity performed by the National Reference Laboratory for Measles and Rubella at the Italian National Institute of Health (Istituto Superiore di Sanità) during 2010. Methods. Urine, oral fluid and capillary blood samples from 211 suspected measles cases arrived to the NRL from different regions of Italy for confirmation of the clinical diagnosis. Serological and/or molecular assays were performed; after molecular detection, positive samples were sequenced and genotyped.Results and discussion. 85% (180/211) of the specimens were confirmed as measles cases and 139 of these were analyzed phylogenetically. The phylogenetic analysis revealed a co-circulation of D4 and D8 genotypes for the reviewed period

Characteristics of COVID-19 cases in Italy from a sex/gender perspective

Introduction: Coronavirus disease 19 (COVID-19) is an infectious disease caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). To date, few data on clinical features and risk factors for disease severity and death by gender are available. Aim: The current study aims to describe from a sex/gender perspective the characteristics of the SARS-CoV-2 cases occurred in the Italian population from February 2020 until October 2021. Method and results: We used routinely collected data retrieved from the Italian National Surveillance System. The highest number of cases occurred among women between 40 and 59 years, followed by men in the same age groups. The proportion of deaths due to COVID-19 was higher in men (56.46%) compared to women (43.54%). Most of the observed deaths occurred in the elderly. Considering the age groups, the clinical outcomes differed between women and men in particular in cases over 80 years of age; with serious or critical conditions more frequent in men than in women. Conclusions: Our data clearly demonstrate a similar number of cases in women and men, but with more severe disease and outcome in men, thus confirming the importance to analyse the impact of sex and gender in new and emerging diseases

Increasing situational awareness through nowcasting of the reproduction number

The time varying reproduction number R is a critical variable for situational awareness during infectious disease outbreaks, but delays between infection and reporting hinder its accurate estimation in real time. We propose a nowcasting method for improving the timeliness and accuracy of R estimates, based on comparisons of successive versions of surveillance databases. The method was validated against COVID-19 surveillance data collected in Italy over an 18-month period. Compared to traditional methods, the nowcasted reproduction number reduced the estimation delay from 13 to 8 days, while maintaining a better accuracy. Moreover, it allowed anticipating the detection of periods of epidemic growth by between 6 and 23 days. The method offers a simple and generally applicable tool to improve situational awareness during an epidemic outbreak, allowing for informed public health response planning

Focolaio di COVID-19 in un campo estivo nella Regione Piemonte (2021): descrizione, lezioni apprese e raccomandazioni per futuri campi estivi

COVID-19 outbreak at a summer camp in Piedimont region in 2021: description, lessons learned and recommendations for future summer camps Introduction In August 2021, an outbreak of coronavirus disease 2019 (COVID-19) occurred in a summer camp in Piedmont region, Italy, affecting primarily campers aged ≤16 years. We conducted a retrospective cohort study among campers and personnel (attendees) to determine the attack rate (AR), evaluate possible factors associated with transmission and propose recommended measures for the organization of future summer camps. Materials and methods A de-identified database including demographic, role of attendees, cohorting, means of transportation to the camp, inter-camper interactions, SARS-CoV-2 testing results and symptomatology was used. All analysis data came from a collection of data carried out by the organizing private company and the information related to the mitigation protocol put in place was provided by the health care personnel. All campers were asked to have an antigen/molecular test within 72 hours before departure. Nine dedicated buses departed from different Italian regions towards the camp. All travellers wore a surgical mask during the trip. Upon arrival, regardless of the bus used, the campers were divided into 11 subgroups with no further contact between them unless they were blood relatives. No SARS-CoV-2 screening tests were scheduled for campers after arrival and during the camp period. On the other hand, personnel had a screening test at each shift change. During the camp period, antigen tests were performed at cases with symptoms suggestive of infection. Only attendees enrolled in the private company and those who received at least one test since arrival at the camp were considered in the study. We calculated overall AR and relative risk (RR) along with specific, transmission-focused risk factors. Results Among the 187 study participants, the median age was 14 years (range: 6-45). Seven days after arrival at the camp, 8 campers developed symptoms and tested positive. The overall AR was 33.7% (63 out of 187), and 34.2% (50/146) for campers and 31.7% (13/41) for staff, respectively. Among those with available symptoms information, 72% (36/50) were asymptomatic at the time of testing. Only 17.1% of campers had direct contact with blood relatives from other subgroups. The AR of participants using a bus was 36.2% (59/163) with an RR of 1.18 (95% CI = 0.51-2.73,) and the AR of those belonging to a subgroup was 35% (62/177) with an RR of 3.5 (95% CI = 0.54-22.7). For personnel, participation to a subgroup gave an AR of 38.7% (12/31) and an RR of 3.87 (95% CI = 0.57-26.18). All but four subgroups had a high AR (>33,3). Conclusions Getting tested prior to traveling and campers separation into low-contact subgroups was not sufficient enough to avoid a high number of infections in this summer camp. Analysis did not allow the identification of an index case or helped to understand whether the outbreak originated from the attendees who travelled on the same bus. The high AR observed in all subgroups suggest that there was frequent contact between attendees belonging to different subgroups. Sharing of common areas such as the canteen and contact between attendees are possible factors that have contributed to the spread of the outbreak. The experience gained by the analysis of this data was used for the review of measures for the organization of summer camps in 2022

Relative effectiveness of a 2nd booster dose of COVID-19 mRNA vaccine up to four months post administration in individuals aged 80 years or more in Italy. A retrospective matched cohort study

Several countries started a 2nd booster COVID-19 vaccination campaign targeting the elderly population, but evidence around its effectiveness is still scarce. This study aims to estimate the relative effectiveness of a 2nd booster dose of COVID-19 mRNA vaccine in the population aged >= 80 years in Italy, during predominant circulation of the Omicron BA.2 and BA.5 subvariants. We linked routine data from the national vaccination registry and the COVID-19 surveillance system. On each day between 11 April and 6 August 2022, we matched 1:1, according to several demographic and clinical characteristics, individuals who received the 2nd booster vaccine dose with individuals who received the 1st booster vaccine dose at least 120 days earlier. We used the Kaplan-Meier method to compare the risks of SARS-CoV-2 infection and severe COVID-19 (hospitalisation or death) between the two groups, calculating the relative vaccine effectiveness (RVE) as (1 - risk ratio)X100. Based on the analysis of 831,555 matched pairs, we found that a 2nd booster dose of mRNA vaccine, 14-118 days post administration, was moderately effective in preventing SARS-CoV-2 infection compared to a 1st booster dose administered at least 120 days earlier [14.3 %, 95 % confidence interval (CI): 2.2-20.2]. RVE decreased from 28.5 % (95 % CI: 24.7-32.1) in the time-interval 14-28 days to 7.6 % (95 % CI: -14.1 to 18.3) in the time-interval 56-118 days. However, RVE against severe COVID19 was higher (34.0 %, 95 % CI: 23.4-42.7), decreasing from 43.2 % (95 % CI: 30.6-54.9) to 27.2 % (95 % CI: 8.3-42.9) over the same time span. Although RVE against SARS-CoV-2 infection was much reduced 2-4 months after a 2nd booster dose, RVE against severe COVID-19 was about 30 %, even during prevalent circulation of the Omicron BA.5 subvariant. The cost-benefit of a 3rd booster dose for the elderly people who received the 2nd booster dose at least four months earlier should be carefully evaluated