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  1. Article ; Online: Estimates of Serial Interval and Reproduction Number of Sudan Virus, Uganda, August-November 2022.

    Marziano, Valentina / Guzzetta, Giorgio / Longini, Ira / Merler, Stefano

    Emerging infectious diseases

    2023  Volume 29, Issue 7, Page(s) 1429–1432

    Abstract: We estimated the mean serial interval for Sudan virus in Uganda to be 11.7 days (95 CI% 8.2-15.8 days). Estimates for the 2022 outbreak indicate a mean basic reproduction number of 2.4-2.7 (95% CI 1.7-3.5). Estimated net reproduction numbers across ... ...

    Abstract We estimated the mean serial interval for Sudan virus in Uganda to be 11.7 days (95 CI% 8.2-15.8 days). Estimates for the 2022 outbreak indicate a mean basic reproduction number of 2.4-2.7 (95% CI 1.7-3.5). Estimated net reproduction numbers across districts suggest a marked spatial heterogeneity.
    MeSH term(s) Humans ; Hemorrhagic Fever, Ebola/epidemiology ; Ebolavirus ; Uganda/epidemiology ; Disease Outbreaks ; Basic Reproduction Number
    Language English
    Publishing date 2023-06-22
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1380686-5
    ISSN 1080-6059 ; 1080-6040
    ISSN (online) 1080-6059
    ISSN 1080-6040
    DOI 10.3201/eid2907.221718
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Evaluating the effect of targeted strategies as control tools for hypervirulent meningococcal C outbreaks: a case study from Tuscany, Italy, 2015 to 2016.

    Guzzetta, Giorgio / Ajelli, Marco / Miglietta, Alessandro / Fazio, Cecilia / Neri, Arianna / Merler, Stefano / Rezza, Giovanni / Stefanelli, Paola

    Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin

    2023  Volume 28, Issue 19

    Abstract: BackgroundMeningococcus ( ...

    Abstract BackgroundMeningococcus (
    MeSH term(s) Humans ; Disease Outbreaks/prevention & control ; Italy/epidemiology ; Meningococcal Infections/epidemiology ; Meningococcal Infections/prevention & control ; Meningococcal Infections/microbiology ; Meningococcal Vaccines ; Neisseria meningitidis ; Neisseria meningitidis, Serogroup C
    Chemical Substances Meningococcal Vaccines
    Language English
    Publishing date 2023-05-11
    Publishing country Sweden
    Document type Evaluation Study ; Journal Article
    ZDB-ID 1338803-4
    ISSN 1560-7917 ; 1025-496X
    ISSN (online) 1560-7917
    ISSN 1025-496X
    DOI 10.2807/1560-7917.ES.2023.28.19.2200650
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: The decline of the 2022 Italian mpox epidemic: Role of behavior changes and control strategies.

    Guzzetta, Giorgio / Marziano, Valentina / Mammone, Alessia / Siddu, Andrea / Ferraro, Federica / Caraglia, Anna / Maraglino, Francesco / Rezza, Giovanni / Vespignani, Alessandro / Longini, Ira / Ajelli, Marco / Merler, Stefano

    Nature communications

    2024  Volume 15, Issue 1, Page(s) 2283

    Abstract: In 2022, a global outbreak of mpox occurred, predominantly impacting men who have sex with men (MSM). The rapid decline of this epidemic is yet to be fully understood. We investigated the Italian outbreak by means of an individual-based mathematical ... ...

    Abstract In 2022, a global outbreak of mpox occurred, predominantly impacting men who have sex with men (MSM). The rapid decline of this epidemic is yet to be fully understood. We investigated the Italian outbreak by means of an individual-based mathematical model calibrated to surveillance data. The model accounts for transmission within the MSM sexual contact network, in recreational and sex clubs attended by MSM, and in households. We indicate a strong spontaneous reduction in sexual transmission (61-87%) in affected MSM communities as the possible driving factor for the rapid decline in cases. The MSM sexual contact network was the main responsible for transmission (about 80%), with clubs and households contributing residually. Contact tracing prevented about half of the potential cases, and a higher success rate in tracing contacts could significantly amplify its effectiveness. Notably, immunizing the 23% of MSM with the highest sexual activity (10 or more partners per year) could completely prevent new mpox resurgences. This research underscores the importance of augmenting contact tracing, targeted immunization campaigns of high-risk groups, and fostering reactive behavioral changes as key strategies to manage and prevent the spread of emerging sexually transmitted pathogens like mpox within the MSM community.
    MeSH term(s) Male ; Humans ; Homosexuality, Male ; HIV Infections/prevention & control ; Mpox (monkeypox) ; Sexual and Gender Minorities ; Sexual Behavior ; Italy/epidemiology
    Language English
    Publishing date 2024-03-13
    Publishing country England
    Document type Journal Article
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-024-46590-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Early prediction of SARS-CoV-2 reproductive number from environmental, atmospheric and mobility data: A supervised machine learning approach.

    Caruso, Pier Francesco / Angelotti, Giovanni / Greco, Massimiliano / Guzzetta, Giorgio / Cereda, Danilo / Merler, Stefano / Cecconi, Maurizio

    International journal of medical informatics

    2022  Volume 162, Page(s) 104755

    Abstract: Introduction: SARS-CoV-2 was declared a pandemic by the WHO on March 11th, 2020. Public protective measures were enforced in every country to limit the diffusion of SARS-CoV-2. Its transmission, mainly by droplets, has been measured by the effective ... ...

    Abstract Introduction: SARS-CoV-2 was declared a pandemic by the WHO on March 11th, 2020. Public protective measures were enforced in every country to limit the diffusion of SARS-CoV-2. Its transmission, mainly by droplets, has been measured by the effective reproduction number (Rt) that counts the number of secondary cases caused in a population by an average infectious individual at time t. Current strategies to calculate Rt reflect the number of secondary cases after several days, due to a delay from symptoms onset to reporting. We propose a complementary Rt estimation using supervised machine learning techniques to predict short term variations with more timely results.
    Material and methods: Our primary goal was to predict Rt of the current day in the twelve provinces of Lombardy with the highest possible accuracy, and with no influence of the local testing strategies. We gathered data about mobility, weather, and pollution from different public sources as a proxy of human behavior and public health measures. We built four supervised machine learning algorithms with different strategies: the outcome variable was the daily median Rt values per province obtained from officially adopted algorithms.
    Results: Data from 243 days for every province were presented to our four models (from February 15th, 2020, to October 14th, 2020). Two models using differential calculation of Rt instead of the raw values showed the highest mean coefficient of determination (0.93 for both) and residuals reported the lowest mean error (-0.03 and 0.01) and standard deviation (0.13 for both) as well. The one with access to the value of Rt of the day before heavily relied on that feature for prediction, while the other one had more distributed weights.
    Discussion: The model that had not access to the Rt value of the previous day and used Rt differential value as outcome (FDRt) was considered the most robust according to the metrics. Its forecasts were able to predict the trend that Rt values would have developed over different weeks, but it was not particularly accurate in predicting the precise value of Rt. A correlation among mobility, atmospheric, features, pollution and Rt values is plausible, but further testing should be performed.
    Language English
    Publishing date 2022-04-01
    Publishing country Ireland
    Document type Journal Article
    ZDB-ID 1466296-6
    ISSN 1872-8243 ; 1386-5056
    ISSN (online) 1872-8243
    ISSN 1386-5056
    DOI 10.1016/j.ijmedinf.2022.104755
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: How habitat factors affect an Aedes mosquitoes driven outbreak at temperate latitudes: The case of the Chikungunya virus in Italy.

    Solimini, Angelo / Virgillito, Chiara / Manica, Mattia / Poletti, Piero / Guzzetta, Giorgio / Marini, Giovanni / Rosà, Roberto / Filipponi, Federico / Scognamiglio, Paola / Vairo, Francesco / Caputo, Beniamino

    PLoS neglected tropical diseases

    2023  Volume 17, Issue 8, Page(s) e0010655

    Abstract: Background: Outbreaks of Aedes-borne diseases in temperate areas are not frequent, and limited in number of cases. We investigate the associations between habitat factors and temperature on individuals' risk of chikungunya (CHIKV) in a non-endemic area ... ...

    Abstract Background: Outbreaks of Aedes-borne diseases in temperate areas are not frequent, and limited in number of cases. We investigate the associations between habitat factors and temperature on individuals' risk of chikungunya (CHIKV) in a non-endemic area by spatially analyzing the data from the 2017 Italian outbreak.
    Methodology/principal findings: We adopted a case-control study design to analyze the association between land-cover variables, temperature, and human population density with CHIKV cases. The observational unit was the area, at different scales, surrounding the residence of each CHIKV notified case. The statistical analysis was conducted considering the whole dataset and separately for the resort town of Anzio and the metropolitan city of Rome, which were the two main foci of the outbreak. In Rome, a higher probability for the occurrence of CHIKV cases is associated with lower temperature (OR = 0.72; 95% CI: 0.61-0.85) and with cells with higher vegetation coverage and human population density (OR = 1.03; 95% CI: 1.00-1.05). In Anzio, CHIKV case occurrence was positively associated with human population density (OR = 1.03; 95% CI: 1.00-1.06) but not with habitat factors or temperature.
    Conclusion/significance: Using temperature, human population density and vegetation coverage data as drives for CHIKV transmission, our estimates could be instrumental in assessing spatial heterogeneity in the risk of experiencing arboviral diseases in non-endemic temperate areas.
    MeSH term(s) Animals ; Humans ; Aedes ; Chikungunya virus ; Case-Control Studies ; Italy/epidemiology ; Chikungunya Fever/epidemiology ; Disease Outbreaks
    Language English
    Publishing date 2023-08-17
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2429704-5
    ISSN 1935-2735 ; 1935-2735
    ISSN (online) 1935-2735
    ISSN 1935-2735
    DOI 10.1371/journal.pntd.0010655
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Reporting delays of chikungunya cases during the 2017 outbreak in Lazio region, Italy.

    Manica, Mattia / Marini, Giovanni / Solimini, Angelo / Guzzetta, Giorgio / Poletti, Piero / Scognamiglio, Paola / Virgillito, Chiara / Della Torre, Alessandra / Merler, Stefano / Rosà, Roberto / Vairo, Francesco / Caputo, Beniamino

    PLoS neglected tropical diseases

    2023  Volume 17, Issue 9, Page(s) e0011610

    Abstract: Background: Emerging arboviral diseases in Europe pose a challenge due to difficulties in detecting and diagnosing cases during the initial circulation of the pathogen. Early outbreak detection enables public health authorities to take effective actions ...

    Abstract Background: Emerging arboviral diseases in Europe pose a challenge due to difficulties in detecting and diagnosing cases during the initial circulation of the pathogen. Early outbreak detection enables public health authorities to take effective actions to reduce disease transmission. Quantification of the reporting delays of cases is vital to plan and assess surveillance and control strategies. Here, we provide estimates of reporting delays during an emerging arboviral outbreak and indications on how delays may have impacted onward transmission.
    Methodology/principal findings: Using descriptive statistics and Kaplan-Meyer curves we analyzed case reporting delays (the period between the date of symptom onset and the date of notification to the public health authorities) during the 2017 Italian chikungunya outbreak. We further investigated the effect of outbreak detection on reporting delays by means of a Cox proportional hazard model. We estimated that the overall median reporting delay was 15.5 days, but this was reduced to 8 days after the notification of the first case. Cases with symptom onset after outbreak detection had about a 3.5 times higher reporting rate, however only 3.6% were notified within 24h from symptom onset. Remarkably, we found that 45.9% of identified cases developed symptoms before the detection of the outbreak.
    Conclusions/significance: These results suggest that efforts should be undertaken to improve the early detection and identification of arboviral cases, as well as the management of vector species to mitigate the impact of long reporting delays.
    MeSH term(s) Humans ; Chikungunya Fever/diagnosis ; Chikungunya Fever/epidemiology ; Disease Outbreaks ; Italy/epidemiology ; Europe ; Public Health
    Language English
    Publishing date 2023-09-14
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2429704-5
    ISSN 1935-2735 ; 1935-2735
    ISSN (online) 1935-2735
    ISSN 1935-2735
    DOI 10.1371/journal.pntd.0011610
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Priority age targets for COVID-19 vaccination in Ethiopia under limited vaccine supply.

    Galli, Margherita / Zardini, Agnese / Gamshie, Worku Nigussa / Santini, Stefano / Tsegaye, Ademe / Trentini, Filippo / Marziano, Valentina / Guzzetta, Giorgio / Manica, Mattia / d'Andrea, Valeria / Putoto, Giovanni / Manenti, Fabio / Ajelli, Marco / Poletti, Piero / Merler, Stefano

    Scientific reports

    2023  Volume 13, Issue 1, Page(s) 5586

    Abstract: The worldwide inequitable access to vaccination claims for a re-assessment of policies that could minimize the COVID-19 burden in low-income countries. Nine months after the launch of the national vaccination program in March 2021, only 3.4% of the ... ...

    Abstract The worldwide inequitable access to vaccination claims for a re-assessment of policies that could minimize the COVID-19 burden in low-income countries. Nine months after the launch of the national vaccination program in March 2021, only 3.4% of the Ethiopian population received two doses of COVID-19 vaccine. We used a SARS-CoV-2 transmission model to estimate the level of immunity accrued before the launch of vaccination in the Southwest Shewa Zone (SWSZ) and to evaluate the impact of alternative age priority vaccination targets in a context of limited vaccine supply. The model was informed with available epidemiological evidence and detailed contact data collected across different geographical settings (urban, rural, or remote). We found that, during the first year of the pandemic, the mean proportion of critical cases occurred in SWSZ attributable to infectors under 30 years of age would range between 24.9 and 48.0%, depending on the geographical setting. During the Delta wave, the contribution of this age group in causing critical cases was estimated to increase on average to 66.7-70.6%. Our findings suggest that, when considering the vaccine product available at the time (ChAdOx1 nCoV-19; 65% efficacy against infection after 2 doses), prioritizing the elderly for vaccination remained the best strategy to minimize the disease burden caused by Delta, irrespectively of the number of available doses. Vaccination of all individuals aged ≥ 50 years would have averted 40 (95%PI: 18-60), 90 (95%PI: 61-111), and 62 (95%PI: 21-108) critical cases per 100,000 residents in urban, rural, and remote areas, respectively. Vaccination of all individuals aged ≥ 30 years would have averted an average of 86-152 critical cases per 100,000 individuals, depending on the setting considered. Despite infections among children and young adults likely caused 70% of critical cases during the Delta wave in SWSZ, most vulnerable ages should remain a key priority target for vaccination against COVID-19.
    MeSH term(s) Child ; Aged ; Young Adult ; Humans ; Adult ; COVID-19 Vaccines ; Ethiopia ; ChAdOx1 nCoV-19 ; COVID-19 ; SARS-CoV-2 ; Vaccines ; Vaccination
    Chemical Substances COVID-19 Vaccines ; ChAdOx1 nCoV-19 (B5S3K2V0G8) ; Vaccines
    Language English
    Publishing date 2023-04-05
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-023-32501-y
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Evaluation of Waning of SARS-CoV-2 Vaccine-Induced Immunity: A Systematic Review and Meta-analysis.

    Menegale, Francesco / Manica, Mattia / Zardini, Agnese / Guzzetta, Giorgio / Marziano, Valentina / d'Andrea, Valeria / Trentini, Filippo / Ajelli, Marco / Poletti, Piero / Merler, Stefano

    JAMA network open

    2023  Volume 6, Issue 5, Page(s) e2310650

    Abstract: Importance: Estimates of the rate of waning of vaccine effectiveness (VE) against COVID-19 are key to assess population levels of protection and future needs for booster doses to face the resurgence of epidemic waves.: Objective: To quantify the ... ...

    Abstract Importance: Estimates of the rate of waning of vaccine effectiveness (VE) against COVID-19 are key to assess population levels of protection and future needs for booster doses to face the resurgence of epidemic waves.
    Objective: To quantify the progressive waning of VE associated with the Delta and Omicron variants of SARS-CoV-2 by number of received doses.
    Data sources: PubMed and Web of Science were searched from the databases' inception to October 19, 2022, as well as reference lists of eligible articles. Preprints were included.
    Study selection: Selected studies for this systematic review and meta-analysis were original articles reporting estimates of VE over time against laboratory-confirmed SARS-CoV-2 infection and symptomatic disease.
    Data extraction and synthesis: Estimates of VE at different time points from vaccination were retrieved from original studies. A secondary data analysis was performed to project VE at any time from last dose administration, improving the comparability across different studies and between the 2 considered variants. Pooled estimates were obtained from random-effects meta-analysis.
    Main outcomes and measures: Outcomes were VE against laboratory-confirmed Omicron or Delta infection and symptomatic disease and half-life and waning rate associated with vaccine-induced protection.
    Results: A total of 799 original articles and 149 reviews published in peer-reviewed journals and 35 preprints were identified. Of these, 40 studies were included in the analysis. Pooled estimates of VE of a primary vaccination cycle against laboratory-confirmed Omicron infection and symptomatic disease were both lower than 20% at 6 months from last dose administration. Booster doses restored VE to levels comparable to those acquired soon after the administration of the primary cycle. However, 9 months after booster administration, VE against Omicron was lower than 30% against laboratory-confirmed infection and symptomatic disease. The half-life of VE against symptomatic infection was estimated to be 87 days (95% CI, 67-129 days) for Omicron compared with 316 days (95% CI, 240-470 days) for Delta. Similar waning rates of VE were found for different age segments of the population.
    Conclusions and relevance: These findings suggest that the effectiveness of COVID-19 vaccines against laboratory-confirmed Omicron or Delta infection and symptomatic disease rapidly wanes over time after the primary vaccination cycle and booster dose. These results can inform the design of appropriate targets and timing for future vaccination programs.
    MeSH term(s) Humans ; COVID-19 Vaccines ; COVID-19/epidemiology ; COVID-19/prevention & control ; SARS-CoV-2 ; Hepatitis D
    Chemical Substances COVID-19 Vaccines
    Language English
    Publishing date 2023-05-01
    Publishing country United States
    Document type Meta-Analysis ; Systematic Review ; Journal Article ; Research Support, U.S. Gov't, P.H.S. ; Research Support, Non-U.S. Gov't
    ISSN 2574-3805
    ISSN (online) 2574-3805
    DOI 10.1001/jamanetworkopen.2023.10650
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: First outbreak of Zika virus in the continental United States: a modelling analysis.

    Marini, Giovanni / Guzzetta, Giorgio / Rosà, Roberto / Merler, Stefano

    Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin

    2017  Volume 22, Issue 37

    Abstract: Since 2015, Zika virus (ZIKV) has spread throughout Latin and Central America. This emerging infectious disease has been causing considerable public health concern because of severe neurological complications, especially in newborns after congenital ... ...

    Abstract Since 2015, Zika virus (ZIKV) has spread throughout Latin and Central America. This emerging infectious disease has been causing considerable public health concern because of severe neurological complications, especially in newborns after congenital infections. In July 2016, the first outbreak in the continental United States was identified in the Wynwood neighbourhood of Miami-Dade County, Florida. In this work, we investigated transmission dynamics using a mathematical model calibrated to observed data on mosquito abundance and symptomatic human infections. We found that, although ZIKV transmission was detected in July 2016, the first importation may have occurred between March and mid-April. The estimated highest value for R
    Language English
    Publishing date 2017-09-14
    Publishing country Sweden
    Document type Journal Article
    ZDB-ID 1338803-4
    ISSN 1560-7917 ; 1025-496X
    ISSN (online) 1560-7917
    ISSN 1025-496X
    DOI 10.2807/1560-7917.ES.2017.22.37.30612
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: How habitat factors affect an Aedes mosquitoes driven outbreak at temperate latitudes

    Angelo Solimini / Chiara Virgillito / Mattia Manica / Piero Poletti / Giorgio Guzzetta / Giovanni Marini / Roberto Rosà / Federico Filipponi / Paola Scognamiglio / Francesco Vairo / Beniamino Caputo

    PLoS Neglected Tropical Diseases, Vol 17, Iss 8, p e

    The case of the Chikungunya virus in Italy.

    2023  Volume 0010655

    Abstract: Background Outbreaks of Aedes-borne diseases in temperate areas are not frequent, and limited in number of cases. We investigate the associations between habitat factors and temperature on individuals' risk of chikungunya (CHIKV) in a non-endemic area by ...

    Abstract Background Outbreaks of Aedes-borne diseases in temperate areas are not frequent, and limited in number of cases. We investigate the associations between habitat factors and temperature on individuals' risk of chikungunya (CHIKV) in a non-endemic area by spatially analyzing the data from the 2017 Italian outbreak. Methodology/principal findings We adopted a case-control study design to analyze the association between land-cover variables, temperature, and human population density with CHIKV cases. The observational unit was the area, at different scales, surrounding the residence of each CHIKV notified case. The statistical analysis was conducted considering the whole dataset and separately for the resort town of Anzio and the metropolitan city of Rome, which were the two main foci of the outbreak. In Rome, a higher probability for the occurrence of CHIKV cases is associated with lower temperature (OR = 0.72; 95% CI: 0.61-0.85) and with cells with higher vegetation coverage and human population density (OR = 1.03; 95% CI: 1.00-1.05). In Anzio, CHIKV case occurrence was positively associated with human population density (OR = 1.03; 95% CI: 1.00-1.06) but not with habitat factors or temperature. Conclusion/significance Using temperature, human population density and vegetation coverage data as drives for CHIKV transmission, our estimates could be instrumental in assessing spatial heterogeneity in the risk of experiencing arboviral diseases in non-endemic temperate areas.
    Keywords Arctic medicine. Tropical medicine ; RC955-962 ; Public aspects of medicine ; RA1-1270
    Subject code 910
    Language English
    Publishing date 2023-08-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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