Background: Toscana virus (TOSV) is transmitted to humans through bites of infected sand flies. Neuroinvasive TOSV infections are leading causes of meningitis/encephalitis in southern Europe and notifiable in Italy since 2016. In 2022–23, Italy experienced extreme climate anomalies and a concomitant increase in mosquito and tick-borne disease transmission. Aim: To identify the spatiotemporal distribution and risk groups of neuroinvasive TOSV infections in Italy in 2022–23 vs 2016–21. Methods: We retrospectively described all autochthonous, laboratory-confirmed neuroinvasive TOSV cases notified to the national surveillance system in 2016–23 using frequencies, proportions, incidences and incidence risk ratios (IRRs) with 95% CIs, stratified by year, sex, age, region/ autonomous province (AP) of infection/exposure and infection/exposure municipality by urbanisation level. Results: In 2022–23, 276 cases were notified (average annual incidence: 2.34/1,000,000 population) vs 331 cases in 2016–21 (0.92/1,000,000), with increased incidence extending into September. In 2022–23, infections were acquired in 12/21 regions/APs, predominantly in Emilia Romagna (57.6%; 159/276) as in 2016–21, including four regions/APs with no local infections in 2016–21. Similar to 2016–21, during 2022–23 residence in rural municipalities (vs urban), male sex, working age (19–67 years) and age > 67 years (vs ≤ 18 years) were identified as risk factors with IRRs of 2.89 (95% CI: 2.01–4.17), 2.17 (95% CI: 1.66–2.84), 5.31 (95% CI: 2.81–10.0) and 5.06 (95% CI: 2.59–9.86), respectively. Conclusion: Italy experienced a nearly 2.6-fold increase in neuroinvasive TOSV incidence in 2022–23 vs 2016–21. Raising public awareness on risk factors and personal protection measures may enhance prevention efforts.
Human neuroinvasive Toscana virus infections in Italy from 2016 to 2023: Increased incidence in 2022 and 2023
network, Italian Arbovirus Surveillance;network., Italian Arbovirus Surveillance
2025-01-01
Abstract
Background: Toscana virus (TOSV) is transmitted to humans through bites of infected sand flies. Neuroinvasive TOSV infections are leading causes of meningitis/encephalitis in southern Europe and notifiable in Italy since 2016. In 2022–23, Italy experienced extreme climate anomalies and a concomitant increase in mosquito and tick-borne disease transmission. Aim: To identify the spatiotemporal distribution and risk groups of neuroinvasive TOSV infections in Italy in 2022–23 vs 2016–21. Methods: We retrospectively described all autochthonous, laboratory-confirmed neuroinvasive TOSV cases notified to the national surveillance system in 2016–23 using frequencies, proportions, incidences and incidence risk ratios (IRRs) with 95% CIs, stratified by year, sex, age, region/ autonomous province (AP) of infection/exposure and infection/exposure municipality by urbanisation level. Results: In 2022–23, 276 cases were notified (average annual incidence: 2.34/1,000,000 population) vs 331 cases in 2016–21 (0.92/1,000,000), with increased incidence extending into September. In 2022–23, infections were acquired in 12/21 regions/APs, predominantly in Emilia Romagna (57.6%; 159/276) as in 2016–21, including four regions/APs with no local infections in 2016–21. Similar to 2016–21, during 2022–23 residence in rural municipalities (vs urban), male sex, working age (19–67 years) and age > 67 years (vs ≤ 18 years) were identified as risk factors with IRRs of 2.89 (95% CI: 2.01–4.17), 2.17 (95% CI: 1.66–2.84), 5.31 (95% CI: 2.81–10.0) and 5.06 (95% CI: 2.59–9.86), respectively. Conclusion: Italy experienced a nearly 2.6-fold increase in neuroinvasive TOSV incidence in 2022–23 vs 2016–21. Raising public awareness on risk factors and personal protection measures may enhance prevention efforts.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
