Hysteria at fever pitch

Remember severe acute respiratory syndrome and bird flu? We seem destined to relive repeatedly our epidemiological past, and what we always seem to get is two epidemics, not one.

The first is an epizootic or a human epidemic. The second is often an extraordinary epidemic of fear, hysteria and panic, partly orchestrated by government and media comments about how much our health and wellbeing is threatened.

That said, public health authorities have long been concerned about the emergence of a new flu virus that may launch a global pandemic. Flu viruses mutate regularly and easily, and we always seem to be one step behind: reacting rather than anticipating.

There is little doubt that we are long overdue for another flu pandemic. It is 40 years since the last flu pandemic and history suggests that some time in the next few years we will experience another.

The emergence of infections such as SARS, bird flu and swine flu underscores that mutation and change are facts of life, that microbes change in accord with alterations in their environment and in their host, and that our health is often a delicate balance between people, wild and domestic animals, and the microbial world.