drug-resistant Streptococcus pneumoniae (DRSP), a widespread strain of respiratory pathogen that is drug resistant. Until the 1960s S. pneumoniae was almost uniformly susceptible to penicillin alone. In 1967 resistance to penicillin and other microbial drugs was first reported in Australia. It has since spread worldwide. The introduction of pneumococcal conjugate vaccines has reduced the number of these infections substantially.
