Epidemiology of quinolone resistance. Eastern hemisphere.

Both nalidixic acid and fluoroquinolones are used widely in the Eastern hemisphere for a variety of infectious diseases. A surveillance programme for antibiotic resistance in common pathogens has been conducted in the Western Pacific Region of the World Health Organization since 1989. Data on resistance to fluoroquinolones for the years 1992 and 1993 from the 16 participating countries in the Western Pacific, plus published data from Thailand, were collated for common and important pathogens in this region. Overall, fluoroquinolone resistance levels were highest in developing countries and lowest in developed countries, with transitional countries undergoing rapid economic improvement showing intermediate levels of resistance. There was also a trend towards increasing levels of fluoroquinolone resistance between 1992 and 1993. In developed countries, levels of resistance to fluoroquinolones exceeded 10% for only Pseudomonas aeruginosa, Staphylococcus aureus, and Acinetobacter and Providencia species. Resistance levels of 25% or more in Escherichia coli were noted in 3 countries in 1993. In contrast, resistant strains of Salmonella typhi and S. paratyphi A were rare or nonexistent in any country, and only low levels of resistance were detected in Shigella species. Fluoroquinolone resistance appears to be emerging slowly in developed countries and more rapidly in transitional and developing countries. Strenuous efforts will be required in some countries in order to prevent the early obsolescence of these valuable agents.