Once again the World Health Organisation has issued a warning that the level of resistance of many infectious organisms to the drugs commonly employed to control them is approaching a critical level. Dr Gro Harlem Brundtland, the director general of WHO, pronounced on June 12 that, although we now possess antimicrobial medicines effective against almost every major infectious agent, the rapid advance of microbial resistance to them may cause us to lose this advantage.
Governments world-wide will need to make greater efforts to stem the emergence of resistant strains by restricting the use of antibiotics and other remedies to major applications and ceasing to prescribe them for minor conditions. Those human infections which are becoming more and more resistant to chemotherapy include tuberculosis, malaria, human immunodeficiency virus, pneumonia and diarrhoeal complaints. In some countries more than 10 per cent of tuberculosis sufferers show strains which are resistant to the most potent antibacterials available. Some 30 per cent of patients with hepatitis B undergoing lamivudine therapy have become resistant after one year of treatment. More and more patients infected with HIV are developing resistance to zidovudine.
The spread of resistance is being brought about by both inadequate dosage with effective drugs and their excessive use in treating minor infections. In some developing countries there is failure to complete a drug treatment programme because of poverty and lack of resources. Cutting short a treatment may encourage the survival of resistant microbial strains. In wealthier communities there is much overprescribing of antibiotics for conditions where they are inactive, in attempts to satisfy patients who think they should receive treatment. The overall situation is compounded by the continued use of antimicrobial additives in cattle and poultry feeds to increase or accelerate growth.
Dr Brundtland advocates that the public and the medical profession be educated to expect a more restricted therapeutic choice. Moreover, speedier diagnosis that enables treatment to start more promptly is desirable. Meanwhile, more efforts should be made to develop new drugs which are effective where others have failed.