Government officials from each of the 30 EEA countries completed a survey questionnaire in 2007, and officials from 29 of 30 countries completed questionnaires in 2009/2010 (nonresponse, Lichtenstein). Different national infectious disease experts were interviewed for the two survey rounds, with an 89% concordance in their assessments; 18 infectious diseases were evaluated in both rounds and for only 2 (chikungunya and dengue fever) did the proportion of countries reporting an impact change significantly (p < 0.1).
The majority of country representatives indicated that they believed climate change would have an impact on all major categories of infectious diseases (vector-, water-, food-, and rodent-borne) (). Diseases with a low or nonexistent disease burden in Europe (e.g., plague, yellow fever, cholera) were ranked rather low (ECDC 2010a). Here we discuss the results by infectious disease category, planning and preparedness, and surveillance activities. For simplicity, summary estimates are reported for the 2009/2010 survey unless otherwise noted.
Infectious diseases likely to be affected by climate change based on survey responses by infectious disease experts representing EEA countries in 2007 and 2009/2010.
Vector-borne diseases. Individual vector-borne diseases judged by national experts to be likely affected by climate change in the future included Lyme borreliosis (79%), West Nile fever (70%), and tick-borne encephalitis (TBE; 63%) (). About one-fourth of respondents also attributed outbreaks or increases in the incidence of these diseases during the last decade to climate change (30%, 25%, and 22% for Lyme borreliosis, West Nile fever, and TBE, respectively). Other vector-borne disease outbreaks (e.g., leishmaniasis, hantavirus infections; data not shown) tend to occur in low numbers or infrequently, which makes attribution to climate change difficult and limits interpretation.
The data for 2009/2010 were mapped by pathogen and country. Potential effects of future climate change on Lyme borreliosis were of concern to respondents from almost all countries except for officials from three Mediterranean countries (Italy, Malta, and Greece) and two Atlantic countries (Ireland and Iceland) (). Respondents in northern and central Europe thought climate change is likely to affect TBE, and respondents in southern Europe expected effects on West Nile fever ( and ). A larger number of respondents in 2009/2010 than in 2007 felt that climate change would affect chikungunya (52% vs. 17%, p = 0.048) and dengue fever (38% vs. 17%, p = 0.07) in their countries (, ). Experts also reported an increase in the geographic distribution and seasonality of several insect-, tick-, and rodent-borne diseases in their countries in the previous decade ().
Figure 1 Responses from national infectious disease experts from EEA countries, 2009–2010, as to whether specific vector-borne diseases would be affected or not affected by climate change. (A) Borreliosis (Lyme disease). (B) TBE. (C) Hantavirus infections. (more ...)
Figure 2 Responses from national infectious disease experts from EEA countries, 2009–2010, as to whether specific vector-borne diseases would be affected or not affected by climate change, 2009/2010. (A) West Nile fever. (B) Chikungunya fever. (C) Dengue. (more ...)
General changes in insect-, tick-, or rodent-borne diseases in European countries over the last decade, according to infectious disease experts, 2009/2010.a
Countries of the northeast reported expansion in the geographic distribution of tick-borne diseases (Lyme borreliosis and TBE) (), whereas countries of the south reported expansion in the distribution of mosquito-borne diseases (e.g., West Nile fever; ). Both local range contraction and range expansion were reported in the case of leishmaniasis in Portugal ().
Food- and water-borne diseases. A large proportion of the experts indicated that they believed that water-borne diseases would be affected by climate change in the future (). Leptospirosis (56%) and cryptosporidiosis (40%) were cited by the largest number of respondents (, ). However, respondents from only 3 countries (Finland, Romania, and Sweden) reported increases of water-borne diseases over the last decade (data not shown). Drinking water supplies in Europe can be regarded as a potential source of vulnerability to climate change; for example, the extent of the vulnerability may be determined by whether access is via public (e.g., municipal) or private water systems. Respondents indicated that the proportion of their population using private drinking water sources were 1–10% in 12 countries, 11–20% in 2 countries, 21–40% in 2 countries, and > 40% in 1 country. Responses were missing for 9 countries. In all 5 countries that had > 11% of private drinking water sources, experts considered the country to be at risk of water-borne outbreaks from climate change.
Figure 3 Responses from national infectious disease experts from EEA countries, 2009–2010, as to whether specific food- and water-borne diseases would be affected or not affected by climate change. (A) Leptospirosis. (B) Cryptosporidiosis. (C) Salmonellosis. (more ...)
Approximately three-fourths of country experts believed that food-borne infections will be affected by climate change (). During the most recent survey, the majority of country experts listed salmonellosis (60%), campylobacteriosis (54%), and enterovirus infections (50%) as likely to be affected by climate change in the future (). Nearly one-third (9 of 28) of country experts reported an observable increase of food-borne diseases over the last decade, but few attributed the food-borne disease outbreaks to climate change (data not shown).
Planning and preparedness. Only 9 of 27 respondents indicated that their countries had completed a national assessment specifically focused on the potential health impacts of climate change (, ). Coverage of infectious diseases by the assessment was reported to be extensive, adequate, or minimal by 4, 3, and 2 respondents, respectively. However, in 14 of 25 countries where adaptation initiatives had been completed or started, the National Climate Change Team/Committee included consideration of the infectious disease health risks of climate change (). The accuracy of this particular response was verified through a review of all fifth submitted National Communications to the UNFCCC provided by each member state from the end of 2009 to the end of 2010 (UNFCCC 2010). A 100% concordance was found between the statements of the experts regarding the health contents of the UNFCC communications and the actual contents of these reports. National preparedness measures reported by the government officials are listed in , and an assessment of the effectiveness of institutions that monitor and provide health services for infectious diseases is provided in . Seventeen countries reported plans to respond to the potential threats from climate change–sensitive infectious diseases through surveillance, monitoring, regulations, resource allocation, or communication strategies.
Planning and preparedness for infectious disease threats attributed to climate change in Europe, according to infectious disease experts, 2009/2010.
Figure 4 Responses from national infectious disease experts, 2009/2010, as to whether their countries had (A) performed national assessments of health impacts from climate change; (B) considered infectious disease health risk as a result of climate change; and (more ...)
Figure 5 Responses from national infectious disease (ID) experts, 2009/2010, as to the effectiveness of institutions, health services, and surveillance programs for vector-, water-, and food-borne diseases by EEA countries. The y-axis represents the EEA countries, (more ...) Surveillance activities.
Several member states reported national, regional, or local surveillance activities (e.g., sentinel or cluster surveillance) for diseases they consider to be climate sensitive in addition to routine surveillance for EU-reportable communicable diseases (European Commission 1999
). For example, five countries (Czech Republic, France, Hungary, Latvia, and Norway) reported surveillance of TBE, one of them since 1953; four countries (Czech Republic, France, Latvia, and Norway) reported surveillance of Lyme borreliosis at least on a regional level; and three countries reported surveillance of hantavirus infections (France, Hungary, and Latvia). Other pathogens covered by nonmandatory surveillance activities in at least one country included Crimean-Congo hemorrhagic fever, dengue fever, echinococcosis, human granulocytic anaplasmosis, hemorrhagic fever with renal syndrome, Mediterranean spotted fever, Naegleria fowleri
infections, norovirus infections, Rift Valley fever, Q fever, rotavirus infections, and yellow fever.
Government officials also assessed current surveillance programs, diagnostic support, collaboration with the veterinary sector, and outbreak response ( and ). A number of respondents reported the need for at least some improvement in these programs, particularly in current surveillance systems (83%) and collaboration with veterinary services (69%).