Authors response: Measles outbreak linked to an international dog show in Slovenia, 2014.

The letter by Filia et al. [1] provides interesting additional information on the measles outbreak linked to an international dog show, reported in our paper recently published in Eurosurveillance [2]. After its publication, no additional measles cases linked to this outbreak were reported in Slovenia, and the number has remained at 44. Together with 18 Italian cases and one detected in Belgium, this gives a total of 63 measles cases linked to this outbreak. In addition to data on measles cases, the Italian authors have also provided data on age and vaccination status of the participants at the dog show. In Slovenia, we only focused on measles cases and contact tracing; demographic information for the Slovenian participants at the dog show was not available. The median age of participating population from Italy was 45 years, five years higher than the median age of the cases reported in Slovenia. Data on vaccination status of the Slovenian participants were not available. The majority (77.1%) of the Italian participants was unvac-cinated. In Slovenia, vaccination coverage was high during the last decades, thus we assume that a smaller proportion of the participants were unvaccinated since also the proportion of unvaccinated cases was smaller (23/44; 52%). When comparing the median age of Italian and of Slovenian measles cases, our cases were older (31 in Italy as compared with 40 years of age in Slovenia). In addition, the vaccination status of the cases was different: among Italian cases only two (11%) were vaccinated with one dose, while nearly half (21/44) of the Slovenian cases were vaccinated with one (nine cases) or two (12 cases) doses. It is interesting to note that among 18 Italian measles cases detected, there were mostly women, only two cases were in men (though 47.4% of participants were male), while nearly half (19/44) of the Slovenian cases were male. Molecular characterisation of viruses from cases linked to international mass gatherings is important for tracing international measles virus transmission pathways, but not always helpful in identifying country of origin. Namely, in 2014, measles virus D8 (with exact matching sequence) has been identified in many European countries [2]. In Slovenia, D8 genotype was also observed in one of the cases linked to the outbreak in Bosnia and Herzegovina which were reported in the same period (November to December 2014) [2]. It is worth mentioning that there was another dog show in Ljubljana in January …