A report in the UK Guardian newspaper (May 25 2006) set me thinking. Dale Griffin of the US Geological Survey explained how bacteria and fungus from Africa can be carried thousands of miles. Desert storms can blow the organisms 3 miles high. Dr Griffn explained that probably 90% will be killed, but some will survive their exposure to the sun’s radiation:
"Among 40 tests of air samples taken in the mid-Atlantic, 24 revealed living microbes, including 26 colonies of bacteria and 83 fungi. They included strains capable of causing disease in humans, animals and plants. A typical gram of Sahara soil contains up to 1bn bacteria, and estimates suggest 2bn tonnes of soil particles are blown around the planet each year. Dr Griffin and his team used genetic testing to establish the exact origin of the organisms."
Many practitioners who test for fungi and bacteria occasionally find clients who appear to have been exposed to organisms they could not, in theory, have encountered. This research suggests how this could occur.
Another study in 2014 by an international team of scientists, including researchers from the University of California, San Diego, reports that the likely causative agent of Kawasaki disease (KD) in Japan is a windborne agent originating from a source in northeast China. KD is a mysterious childhood ailment that can permanently damage coronary arteries.
KD is the most common cause of acquired heart disease in children. It is difficult to diagnose and, without treatment, 25 percent of children with KD develop coronary artery aneurysms -- balloon-like bulges of heart vessels -- that may eventually result in heart attacks, congestive heart failure or sudden death. Prevalence rates of KD are rising among children in Asia, the United States and Western Europe. Predictive models estimate that by 2020 one in every 1,600 adults in the U.S. will be affected by the disease.
The multidisciplinary team of Rodó, Burns, Dan Cayan, PhD, a climate researcher at UC San Diego Scripps Institution of Oceanography and co-authors in New York, Barcelona and Japan, say the new evidence suggests that the most likely cause of KD is a "preformed toxin or environmental molecule" originating from northeastern China, possibly related to Candida, which has been linked to Kawasaki-like coronary artery vasculitis in mouse models.
Burns summarized the major findings:
- Prevailing wind patterns associated with KD cases in Japan track back to northeastern China, which is the country's main cereal grain-growing region.
- KD has a short incubation time (less than 24 hours between exposure and fever onset), suggesting the cause is not a traditional infectious organism, but more likely a toxin, perhaps fungal in origin, that readily triggers a host immune response in genetically susceptible children.
- Air sampling in Japan during the winter KD season found unexpectedly high levels of Candida species within the rich microbiome of tropospheric winds.
All this is a reminder of how far different particles can travel. Volcanic dust, for example, has been shown to travel thousands of miles, crossing continents with ease. Samples of dust layers taken in the Lewis Cliff/Beardmore Glacier area in Antarctica were identified as consisting of volcanic ash, probably originating from Australia. Industrial pollution has been found far from man’s activity. International travel applies to bacteria, candida and dust particles as well as people.
Jane Thurnell-Read (c) 2014