Evidence that global warming is affecting cyanobacterial populations comes from the substantial extension of their geographical ranges. One example is Cylindrospermopsis raciborskii, which was responsible for a mysterious outbreak of severe hepatitis-like illness in Palm Island, Australia (W. W. Carmichael, Human Ecol. Risk Assess. 7:1393, 2001). Originally a tropical and subtropical species, it has moved into higher and higher latitudes and is now widespread in the lakes of northern Germany.
All of these developments point towards a new agenda and a new challenge for microbiologists in seeking to understand and where possible ameliorate some of the consequences of global warming. Another major component of that agenda is, of course, the direct impact of raised average temperature on human pathogens and their vectors. Whereas just a decade ago, discussion was largely restricted to speculations founded on computer modeling, there are now more tangible grounds for concern.
Writing in The Lancet (367:863, 2006), Anthony McMichael and colleagues have argued that, while no one study is conclusive, several reports have already indicated effects of global warming on some infections. For example, in association with alterations in climate, the geographical range of ticks that transmit Lyme borreliosis and viral encephalitis has extended northwards in Sweden and increased in altitude in the Czech Republic. Also, changes in the intensity (amplitude) of the El Niño cycle since 1975, and more recently its frequency, have accompanied the strengthening of the relationship between the cycle and cholera outbreaks in Bangladesh.
Source: 2008 American Society for Microbiology
Aporte: Guillermo Figueroa
Source: 2008 American Society for Microbiology
Aporte: Guillermo Figueroa
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