> None of the ones listed seem to survive for the periods we generally associate with AFB spores which we discuss as being decades long.
Of course, there is great variation in the ability of micro-organsims to to survive. Supposedly, 25-40-million-year-old bacterial spores were discovered in a bee preserved in amber. The following suggests that spores can be protected by sugar solution
LONG-TERM SURVIVAL OF BACTERIAL SPORES IN SPACE
After nearly six years in space vacuum, there is still a considerable amount of viable spores (1 - 2 %), even if exposed in a monolayer without any protection against dehydration (Figure 2). Spores in a multilayer survive even less (0.3 %) than in a monolayer (Figure 3). The survival is significantly increased, if protecting substances are present, such as buffer salts or glucose (Figures 2 and 3). The protecting effect is especially pronounced for spores in a multilayer. In this case, e.g. multilayer with glucose present, nearly 70 % of the spores survive nearly 6 years exposure to space vacuum. This response to vacuum is confirmed in the ground controls, kept in simulated space conditions. Sugars and polyalcolhols are suggested to stabilize the structure of cellular macromolecules, especially during vacuum-induced dehydration.
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Viruses are another matter, I couldn't find anything to show that viruses are infective longer than half a year. Might have to keep looking.
VIRUS SURVIVAL IN THE ENVIRONMENT
At moderate and low temperatures (and intermediate pH levels of 5-9), viruses can persist for considerable periods of time that may range from hours to days to weeks to even months in the case of the most persistent viruses. The rate of inactivation and the extent of survival varies, depending on virus type, temperature, suspending medium and other environmental conditions.
In studies examining the persistence of representatives of several families and genera of viruses (adenovirus, poliovirus, coxsackievirus, vaccinia virus, and herpes simplex type 1) on inanimate surfaces, survival was found to vary with virus type {Mahl, 1975 #366}. Adenoviruses were most persistent, surviving for greater than 12 weeks at low humidity.
One of the more environmentally persistent animal viruses is Aujeszky’s disease virus … virus inactivation rates increased with increasing temperature. Virus was inactivated at 5 and 20 oC in 15 weeks and 2 weeks, respectively. At 35 oC (mesophilic conditions) the virus was inactivated in 5 hours and at 55 oC (thermophilic conditions) no virus could be detected after 10 minutes.
references available on request
PLB
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