Leading Article: How frightened should we be?

AT FIRST sight, the media coverage of streptococcus A, the bacterium responsible for the deaths of at least 12 patients over recent months, seems overblown. More cases have been reported this year than in 1992 or 1993, and the concentration in Gloucestershire of seven cases seems unusual. However, the current spate may still be no more than a statistical blip.

Fears of a conspiracy of silence among medical experts are wide of the mark. Although it is in the nature of administrators to try to minimise public anxiety, the National Health Service is too open an institution for the concerns of doctors about the spread of the bacterium to be deliberately hidden.

'The standard mechanism for keeping tabs on highly infectious diseases is to impose on hospitals and local health authorities a duty to notify cases to the Department of Health. Notification is not a realistic option, however, in the case of streptococcus A. Since the bacterium itself is responsible for 5,000 cases of sore throats in GPs' surgeries every day, notification would impose a huge administrative burden to no purpose. The tiny number of cases in which the bacterium results in necrotising fasciitis - the condition whose causes are not yet fully understood, and in which the patient's flesh is 'liquefied' away in a matter of hours - could not be subjected to separate notification, for fasciitis itself is not believed to be infectious.

Yet despite these arguments against panic measures, the concern among the wider public is understandable. Antibiotics and other drugs have been so successful that we complacently assume that medicine can vanquish all kinds of infectious diseases. Those ailments against which science is less successful tend either to progress very slowly (as with the development of HIV into full- blown Aids) or are rare, as with certain strains of viral pneumonia. The inability of experts to explain the virulence of a bacterium, let alone to counter it, explodes this complacency.

While it is too early for conclusions to be anything other than tentative, the bacterium also offers a wider lesson in public health. Although the bacterium itself is susceptible to treatment by antibiotics, other bacteria are becoming worryingly resistant to antibiotic treatment. This resistance is exacerbated by patients who weaken bacteria with antibiotics but then allow them to survive in mutated form by abandoning the treatment. The best protection against new forms of infectious disease, therefore, may be to follow the instructions on the medicine bottle and finish the course.