Autochthonous dengue outbreak in Northern Italy, September 2024: epidemiological, microbiological, entomological investigation and public health response
Year: 2026
Type: article
Study design: Observational Study
Abstract: BACKGROUND: Dengue is an emerging public health threat in temperate regions of Europe where Aedes albopictus is established. In 2024 Italy experienced an unprecedented increase in autochthonous dengue transmission. In September 2024, a cluster of locally acquired dengue cases was detected in Cavezzo, Emilia-Romagna, Northern Italy. METHODS: An outbreak investigation was initiated following confirmation of the first autochthonous dengue case on 17 September 2024. Enhanced surveillance was activated including retrospective case finding, targeted community screening, and strengthened laboratory diagnostics. Vector control measures were implemented starting within a 200m radius of confirmed cases and expanded based on epidemiological and entomological findings. Blood and organ donation safety measures were introduced, and whole genome sequencing were performed on human and mosquito samples. RESULTS: 44 autochthonous dengue cases were identified with symptom onset between 31 July and 23 September 2024; 68.2% were detected retrospectively. No epidemiologically linked cases were detected outside Cavezzo. Most cases occurred in older adults (median age 63 years); two patients were hospitalised and recovered fully. Dengue virus serotype 2 (DENV-2), genotype II, lineage F.1.1, was detected in both human and Ae. albopictus samples. Phylogenetic analysis identified a distinct cluster separate from sequences associated with the contemporaneous outbreak reported in Fano, Italy. Following vector-control interventions, mosquito density declined and no further virus-positive pools were detected. CONCLUSION: This outbreak highlights the increasing vulnerability of temperate European regions to dengue transmission and underscores the importance of rapid case detection, community engagement, and targeted vector-control strategies in preventing wider spread.
Authors: Jasleen Singh, Tiziana Lazzarotto, Christina Merakou, Giada Rossini, Maurilia Marcacci, Guido Di Donato, Rodolfo Veronesi, Antonino Bella, Giulietta Venturi, Marco Di Luca, Arianna Puggioli, Ilaria Pati, Raffaele Donadio, Rino Biguzzi, Nicola Alvaro, Alessandra Fantuzzi, Flavia Riccardo, Giacomo Creola, Paola Angelini, Giulio Matteo, Mattia Calzolari, Michele Dottori, Patrizio Pezzotti, Chiara Sacco, Martina Del Manso, Francesco Severini, Luciano Toma, Caterina Vocale, Silvia Galli, Liliana Gabrielli, Greta Roncarati, Giulia Piccirilli, Simona Venturoli, Evangelia Petrisli, Giorgio Gallinella, Luca Ruotolo, Beatrice Mola, Isabella Bon, Margherita Ortalli, Fabrizia Valleriani, Angela Taraschi, Chiara Pinoni, Barbara Secondini, Valeria Di Lollo, Alessandro Albieri, Romeo Bellini, Marco Carrieri, Roberta Colonna, Luciano Donati, Debora Ruggeri, Sabina Sanseverinati, Elisabetta Fioretti, Barbara Mai, Carmela Palomba, Miriam Benatti, Giuseppe Diegoli, Giovanna Mattei, Stefano Benedetti, Cristina Liverani, Monica Soracase, Esther Rita De Gioia, Claudio Gualanduzzi, Cinzia Perilli, Alessia Leucci, Annalisa Grisendi, Mara Scremin, Katia Marzani, Deborah Torri, Letizia Lombardini
Institutions: Istituto Superiore di Sanità, European Centre for Disease Prevention and Control, IRCCS Azienda Ospedliero-Universitaria di Bologna Policlinico di Sant'Orsola, University of Bologna, Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise G. Caporale, Centro Agricoltura Ambiente (Italy), Centro Nazionale Sangue, Azienda Unità Sanitaria Locale Della Romagna, Azienda Unita' Sanitaria Locale Di Modena, Regione Emilia-Romagna, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna "Bruno Ubertini"
Language: English
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $3,710
Funder: European Commission
OpenAlex ID: W7154293091