Microbiological Coastal Risks and Monitoring Systems - Vulnerability of Coastal Ecosystems and Adaptation - page 102

Climate change also carries the consequence of increasing sea
levels through the melting of ice on land (Greenland and the
Antarctic) or through the thermal expansion of marine waters. This
rise in water level causes a salinization of coastal continental waters
(saline intrusion in estuaries, deltas, coastal lagoons or in aquifers).
Several species of mosquitoes that are vectors of malarial agents,
dengue or chikungunya, show a tolerance to changes in salinity and
adaptability to its increase [RAM 12]. The risks of emergence,
re-emergence or epidemics are, therefore, to be taken into
consideration in all the deltas and coastal lagoons where these vectors
have the chance to become established.
Climatic variability is a factor in the rise of epidemics. El Niño/La
Niña episodes, as well as the North Atlantic Oscillation (NAO)
variability, are linked to a rise in epidemics of many oral-fecal
diseases (viral or microbial) or to vector transmission [MOR 12,
MOR 13].
3.2.2.2. Changes in biodiversity
Global environmental changes also concern changes in
biodiversity: drops in biodiversity (due to extinctions), migrations
(climate change) and invasions (commerce).
Several studies suggest that the drop in biodiversity, experienced
by a number of species, favors the transmission of vector diseases.
Thus, epidemics of West Nile Fever seem to be encouraged by a drop
in the number of avian species. An increased bird population could
have the consequence of diluting mosquito bites among birds that do
not act as reservoirs of the pathogenic agents that they carry, thus
diminishing the rate of infected bites from hosts to these agents
[KEE 10].
With the movement of 3-6 billion tonnes of ballast water, maritime
transport is considered as the principal source of exchanges and
invasions of species in coastal waters, with more than 10,000 species
transported each year. Among them, microorganisms (pathogens and
toxin genes), parasites, vectors and reservoir hosts constitute so many