RT Journal Article SR Electronic T1 Penicillinase producing strains of Neisseria gonorrhoeae in the West Midlands 1979-83. JF Genitourinary Medicine JO Genitourin Med FD BMJ Publishing Group Ltd SP 234 OP 240 DO 10.1136/sti.61.4.234 VO 61 IS 4 A1 Clay, J C YR 1985 UL http://sti.bmj.com/content/61/4/234.abstract AB All cases of gonorrhoea caused by penicillinase producing strains of Neisseria gonorrhoeae (PPNG) occurring in the population served by the West Midlands Regional Health Authority were surveyed. Isolates that were subjected to plasmid analysis were found to be mainly the "Asian" type in travellers from abroad and their immediate contacts, whereas isolates apparently indigenous in origin were mainly "African" type. The emerging sigmoid curve of yearly incidence, which is apparent for both the country and the region, may indicate that a dynamic equilibrium is being approached in the susceptible core populations. The importance of vigorous contact tracing is underlined by the contrast between the incidence of PPNG strains in the United Kingdom and the larger numbers found in areas where they are hyperendemic and where contact tracing is ineffectual or non-existent.