Climate change impacts and vulnerability in Europe 2016

Climate change impacts on society
5.2.6 Water- and food-borne diseases
Key messages
• It is not possible to assess whether past climate change has already affected water- and food-borne diseases in Europe,
but the sensitivity of pathogens to climate factors suggest that climate change could be having effects on these diseases.
• The number of vibriosis infections, which can be life-threatening, has increased substantially in Baltic Sea states since
1980. This increase has been linked to observed increases in sea surface temperature, which has improved environmental
conditions for Vibrio species blooms in marine waters. The unprecedented number of vibriosis infections in 2014 has
been attributed to the unprecedented 2014 heat wave in the Baltic region.
• Increased temperatures could increase the risk of salmonellosis.
• The risk of campylobacteriosis and cryptosporidiosis could increase in those regions where precipitation or extreme
flooding is projected to increase.
• Climate change can have an impact on food safety hazards throughout the food chain.
Relevance
A rise in air and water temperature, extreme
precipitation events, seasonal changes, storms,
droughts and flooding, associated with climate change,
can have implications for food- and water‐borne
diseases in Europe (Semenza, Herbst, et al., 2012;
Semenza, Houser, et al., 2012) (Table 5.3). These
climatic events can alter growth rates of pathogens,
contaminate drinking, recreational and irrigation water,
and disrupt water treatment and sanitation systems.
Conversely, potential impacts will be modulated by
the quality of food safety measures, the capacity and
quality of water treatment systems, human behaviour
and a range of other conditions.
High air temperatures can adversely affect food quality
during transport, storage and handling. Elevated
marine water temperatures accelerate the growth
rate of certain pathogens, such as Vibrio species that
can cause food-borne outbreaks (seafood). On rare
occasions, they may lead to severe necrotic ulcers,
septicaemia and death in susceptible individuals
exposed during bathing in contaminated marine
environments. Floods and increased water flows can
lead to the contamination of drinking, recreational
or irrigation water and thus can increase the risk of
water‐borne diseases, such as cryptosporidiosis.
Attributing past trends in these diseases, or individual
outbreaks, to climate change is very challenging, owing
to data gaps for selected pathogens and climatic
determinants. For example, legionnaires' disease is
associated with temperature and vapour pressure but
not with climate change per se (Conza et al., 2013).
The current knowledge on the relationship between
climatic factors and the risk associated with several
climate‐sensitive food- and water-borne diseases
(caused by bacteria, viruses and parasites) in Europe is
presented in Table 5.3.
Vibrio species (non-cholera)
Brackish water and elevated ambient temperature
are ideal environmental growth conditions for certain
Vibrio species. These conditions can be found during
the summer months in estuaries and enclosed water
bodies with moderate salinity, such as the Baltic Sea.
In contrast, open ocean environments do not offer
appropriate growth conditions for these bacteria owing
to the high salt content, lower temperature and limited
nutrient content. Of the most relevance to human
health are the Vibrio species that can cause vibriosis
infections, including Vibrio parahaemolyticus, Vibrio
vulnificus and the non-toxigenic Vibrio cholerae.
Elevated levels of non-cholera Vibrio species infections
have been observed during extended hot summer
seasons with water temperatures above 20 °C in the
Baltic Sea and the North Sea (Hemmer et al., 2007;
Baker-Austin et al., 2012; Sterk et al., 2015). The
availability of data is best for the Baltic Sea region,
where a recent analysis found strong links between the
temporal and spatial peaks in sea surface temperatures
and the number and distribution of Vibrio infections.
Figure 5.7 shows the observed and projected levels
of Vibrio infections in the Baltic Sea region from 1982
to 2010, which was a period of unprecedented sea
surface temperature warming (see also Section 3.1)
Climate change, impacts and vulnerability in Europe 2016 | An indicator-based report
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