Tropical and exotic infections

In summary, MDR strains of S. typhi are both epidemic and endemic in many countries in Asia and MDR S. paratyphi A has recently emerged in Pakistan. Multiple clones may be present in a given area at any time. Fluoroquinolones and third generation cephalosporins have been used widely over the past decade to treat MDR strains. The clinical superiority of fluoroquinolones is now threatened by the rapid emergence of chromosomally mediated resistance and cephalosporin resistance is also being reported. Whether these problems can be overcome by the use of newer fluoroquinolones or cephalosporins remains to be seen. Meanwhile, furazolidone and azithromycin deserve further trials, and clinical and molecular surveillance of resistance patterns remains essential.