No. 56: Mar-Apr 1988
Fred Hoyle, in his usual maverick style, has hypothesized that some human flu epidemics are caused by new viruses in jected into the biosphere from outer space. (See his book Diseases from Space.) In yet another book, Evolution from Space, he goes further, stating that the evolution of terrestrial life can also be affected by the extraterrestrial inoculation of genetic material.
But, just maybe, influenza pandemics are due to pigs! Every 10-20 years, new flu viruses seem to crop up against which humans have little resistance. The latest theory is that there exists a human-duck-pig connection. It seems that human flu viruses can multiply in ducks, but are not transmitted among ducks. It is also likely that duck viruses multiply in humans, but are not transmitted from one person to another. But enter the pigs:
"There is firm evidence that pigs can become infected by and may transmit both human and avian influenza viruses not only amongst other pigs but also back to the original hosts. Therefore, pigs seem to be 'mixing vessels' where two separate reservoirs meet and where reassortment between avian and human influenza A viruses occurs, giving rise to the antigenic shift by creating new human pandemic influenza strains with new surface antigens."
The article stimulating this discussion worries about new aquaculture practices, especially in Asia (the so-called Blue Revolution), in which duck and pig manure is dumped into fish ponds as fertilizer. The dense concentration of humans, ducks, and pits threatens to be a factory for constructing new strains of flu. (Scholtissek, Christoph, and Naylor, Ernest; "Fish Farming and Influenza Pandemics," Nature, 331:215, 1988.)
Comment. Noting that the AIDS virus may have originated and still be mutating in African monkeys, and coupling this with the above discussion of flu, we can speculate a la Evolution from Space that terrestrial life itself is its own evolutionary engine! Going still another step further, we can wonder if life-as-a-whole (the Gaia concept) is not trying to check the burgeoning human population by biological warfare -- a check and balance arrangement. Isn't it amazing how much speculation a couple simple facts can engender?