No author listed. Communicable Diseases Intelligence volume 15 issue 7 - 8 April 1991 - whole issue. Commun Dis Intell (2018) [Internet]. 1991 Apr. 8 [cited 2026 Apr. 18];15:115-34. Available from: https://ojs.cdi.cdc.gov.au/index.php/cdi/article/view/2913