Heat Wave–Associated Vibriosis, Sweden and Finland, 2014

Abstract

During summer 2014, a total of 89 Vibrio infections were reported in Sweden and Finland, substantially more yearly infections than previously have been reported in northern Europe. Infections were spread across most coastal counties of Sweden and Finland, but unusually, numerous infections were reported in subarctic regions; cases were reported as far north as 65°N, ≈100 miles (160 km) from the Arctic Circle. Most infections were caused by non-O1/O139 V. cholerae (70 cases, corresponding to 77% of the total, all strains were negative for the cholera toxin gene). An extreme heat wave in northern Scandinavia during summer 2014 led to unprecedented high sea surface temperatures, which appear to have been responsible for the emergence of Vibrio bacteria at these latitudes. The emergence of vibriosis in high-latitude regions requires improved diagnostic detection and clinical awareness of these emerging pathogens.

Application of three different methods to determine the prevalence, the abundance and the environmental drivers of culturableVibrio choleraein fresh and brackish bathing waters

“…For the Baltic Sea—as the most prominent example—where dramatically increasing numbers of V. cholerae infections have been reported in recent years (Baker‐Austin et al . , ), no quantitative data on V. cholerae concentrations are available. In addition, no information is available on the dose–response relationships of V. cholerae nonO1/nonO139 in general and of different V. cholerae serogroups/strains specifically.…”

“…Especially in Northern Europe (Baltic Sea), infections of swimmers have been predominantly caused by V. cholerae nonO1/nonO139 (Baker‐Austin et al . ). Some serious infections of swimmers due to V. cholerae nonO1/nonO139 have also been reported from other European countries (Stypulkowska‐Misiurewicz et al .…”

“…) and maximum values 10°C above the long‐term average have been reported during a recent heatwave in the Baltic Sea (Baker‐Austin et al . ). It is well known that higher temperatures enhance growth of V. cholerae and other Vibrios (Huq et al .…”

“…The observed increase in infection frequency has been linked to global warming and the significantly increased water temperatures observed in many aquatic environments (Baker‐Austin et al . ; Vezzulli et al . ).…”

“…In the past two decades, Vibrio-associated infections have been significantly increasing in Europe and the United States of America (Newton et al 2012;Baker-Austin et al 2013;Le Roux et al 2015;Vezzulli et al 2016). Especially in Northern Europe (Baltic Sea), infections of swimmers have been predominantly caused by V. cholerae nonO1/nonO139 (Baker-Austin et al 2016b). Some serious infections of swimmers due to V. cholerae nonO1/nonO139 have also been reported from other European countries (Stypulkowska-Misiurewicz et al 2006;Huhulescu et al 2007;Sterk et al 2015;Dobrovic et al 2016;Engel et al 2016;Hirk et al 2016;Maraki et al 2016).…”