ANTS AND ANAPHYLAXIS
11/4/03 In South East Australia the jack jumper ant, Myrmecia pilosula, is responsible for about 90% of anaphylaxis due to ant venom. In Tasmania the rate of clinical systemic allergy to the venom is 2.7%, twice the rate for bee stings, and deaths have been reported.
Bob Heddle, immunologist at Flinders Medical Centre and a DEA member, together with colleagues at the Royal Hobart Hospital is working on a hyposensitisation treatment for sufferers from the bite of this ant. Treatment was shown to be effective in a double blind crossover trial and the results of the study have been published in The Lancet, 22 March 2003
The jack jumper ant provides us with us with an interesting clinical and ecological vignette. The ant is 10 to 12 mm long and jet black apart from yellow-orange mandibles and leg tips. When it attacks it jumps, attaches with its mandibles and injects venom with its abdominal stinger. The probable increase in the numbers and distribution of the jack jumper seems to relate to the proliferation of human dwellings followed by the decline in the numbers of echidna. The echidna, an important predator of the ant, is reclusive and is deterred by development. This is a strong reminder that human disturbance of ecological balance can have implications for human health. Indeed, globally ant bites are becoming more important as causes of death and many examples relate to ‘imported’ ants such as the fire ant which can proliferate rapidly because there are no natural predators in its new environment
Putting aside the disagreeable habits of the jack jumper and other ants, we can learn much from the organisation of ant colonies. A colony has a collective intelligence, a collective brain that manages a complicated and cohesive society. It is not an authoritarian regime but one that is organised from the bottom up and which is being used to study the evolution of human urban conurbations. Some feel that the colony offers some interesting insights into collective responsibilities and how they might be organised in the human world of rampant individualism and conflict! Finally, you will note that the development of the computer, the artificial brain is essentially a bottom up creation. Read “Emergence” by Steven Johnson, published by Allen Lane.