No author listed. Communicable Diseases Intelligence volume 15 issue 8 - 22 April 1991 - whole issue. Commun Dis Intell (2018) [Internet]. 1991 Apr. 22 [cited 2026 Apr. 10];15:136-48. Available from: https://ojs.cdi.cdc.gov.au/index.php/cdi/article/view/2914