Confirmed the presence of Bluetongue in Aosta Valley region

On 9 September 2024, two clinical outbreaks of bluetongue (BT), serotype 8 (BTV-8), were reported in the Aosta Valley region, in the municipalities of Perloz and Aosta. These outbreaks, both affecting cattle, caused in the suspension of the “disease free” status for the region, as communicated by ministerial note DGSAF 0027276/2024 .

In Italy,in 2024, 354 outbreaks of BTV-8 have been notified by the competent authority  through SIMAN (Animal Disease Information System), of which 94% are clinical outbreaks.

In Sardinia, five outbreaks of serotype 8 had already been reported between January and February. Moreover, with the onset of the vector season, identified at Italian latitude between late summer and late autumn, numerous BT outbreaks have also been reported in mainland Italy.

As of 12 September 2024, in addition to the two outbreaks in the Aosta Valley, for BTV-8 the following were notified by the competent authority:

• 180 in Sardinia
• 89 in Piedmont
• 45 in Calabria
• 19 in Lombardy
• 9 in Emilia Romagna
• 8 in Sicily
• 2 in Liguria.

In terms of affected species, 318 outbreaks involved sheep, 43 cattle, 11 goats, 2 alpacas, and 1 camel.

In Europe, 15 outbreaks have been reported in 2024 (7 in Spain, 7 in Andorra and one in Switzerland).

Bluetongue is a non-contagious viral disease transmitted by a vector (biting midges) of the genus Culicoides. It affects both domestic and wild ruminants, with morbidity in sheep reaching up to 100%. In past seasons in Europe, serotype 8 had affected an unusually large number of cattle².

For serotype 8, during the 2023 season, 243 outbreaks were notified in Sardinia (in the provinces of Nuoro, Oristano, South Sardinia, and Gallura Northeast Sardinia) and one in Tuscany (in the province of Grosseto).

Other serotypes reported in BT outbreaks are serotype 3 (485 outbreaks in Sardinia), serotype 4 (53 outbreaks in Abruzzo, Basilicata, Campania, Emilia Romagna, Lazio, Liguria, Lombardy, Marche, Molise, Puglia, Sardinia, Sicily, and Tuscany), and 21 outbreaks in Lombardy and Sardinia for which the serotype has yet to be identified.

The latest notes issued by the ministry of health are available on the National Information System for Bluetongue .

References

1. Purse, B. V., Mellor, P. S., Rogers, D. J., Samuel, A. R., Mertens, P. P., & Baylis, M. (2005). Climate change and the recent emergence of bluetongue in Europe. Nature reviews microbiology, 3(2), 171-181.
2. WOAH, 2021 – Blue tongue technical card