In 1994 there was widespread reporting by the media of a ‘flesh eating bug’ in the UK. This ‘superbug’ was ‘destroying human flesh at the rate of one inch per hour’!
The media hype led to widespread public anxiety. In fact, the condition – necrotising fasciitis – is caused by Streptococcus pyogenes, and is a very rare complication of surgery or other debilitating conditions.
In many instances during the reporting of this case, the microbe responsible was wrongly labelled as a virus. It was also suggested that bacteriophages – a particular type of virus – were altering the genetic makeup of the Streptococcus bacteria. The alterations were thought to make it more virulent and resistant to antibiotics, therefore leading to an epidemic of the condition.
A basic understanding of the differences between bacteria and viruses would have alleviated the concerns of the public, since much of what was reported was at best misleading, and at worst blatantly wrong
If the immune system is unable to deal with the invasion into the body of pathogenic bacteria, antibiotic drugs might be prescribed. There are many types of antibiotics that act on bacteria, including: the Aminoglycosides (eg. Gentamycin and Streptomycin), Chloramphenicol, Cephalosporins, Penicillins (eg. Amoxicillin), and the Tetracyclines.
In the past, antibiotic drugs were often prescribed for viral conditions, such as the common cold and viral sore throats, despite being ineffective against viruses. The resulting overuse is one of the factors contributing to antimicrobial resistance.
Antibiotic resistance can occur in a number of ways. Bacteria replicate rapidly, and mutations can arise in their DNA. If a mutation gives rise to bacteria that are less susceptible (and therefore more resistant) to the actions of the antibiotic, then this form of the bacteria will survive and continue to replicate. This is why it is so important to complete a course of antibiotic treatment – if a resistant form of the bacteria is allowed to proliferate in the body, later antibiotic treatment to combat a subsequent infection will have no effect.
Likewise, prolonged or overuse of antiviral drugs (such as those used to treat HIV) can lead to antiviral resistance. Usually, however, viral infections are removed by the body’s immune system. Community-wide immunisation programmes also reduce the risk of viral epidemics.
|Dixon, B (1994) A rampant non-epidemic, BMJ 308:1567-1577.||Sets out the facts ignored by the media in their coverage of the ‘superbug’.|
|National Institute of Allergy and Infectious Diseases, Microbes in sickness and in health (PDF)||Describes the various types of microbes and explains their effects on people. [Original URL: http://www.niaid.nih.gov/publications/microbes.htm]|