title: Trends in multidrug-resistant Mycobacterium tuberculosis in relation to sputum smear positivity in Hong Kong, 1989-1999.
abstract: We studied retrospectively the territory-wide occurrence and trends of multidrug-resistant tuberculosis (MDR-TB) in Hong Kong over an 11-year period during which a short-course directly observed therapy ("DOTS-Plus") strategy has been in operation. The overall MDR rate was 2.1% (primary, 1.4% and acquired, 9.5%) and declined at 0.08% per year: smear-positive primary MDR cases declined at yearly rate of -0.065% (R2=.23), and smear-negative primary MDR cases increased at 0.035% yearly. With declining rates of smear positivity, sputum culture has become the mainstay of detection of MDR-TB. Although the overall notification rates showed the elderly (age >65 years) age group to be most affected, the occurrence of MDR-TB has been consistently highest in the 35-65 year age group (60.4% of MDR caseload). We demonstrated declining rates of sputum smear positivity of MDR-TB in a DOTS-plus environment and that a centralized laboratory database is essential in gathering epidemiological information for identifying particular risk groups and monitoring trends of MDR-TB in a community.
authors.affiliation: Tuberculosis Reference Laboratory, Department of Health, Yung Fung Shee Memorial Centre, Cha Kwo Ling Road, Kwun Tong, Hong Kong. kmkam@dh.gov.hk
authors.forename: Kai Man
authors.initials: KM
authors.lastname: Kam
authors.forename: Chi Wai
authors.initials: CW
authors.lastname: Yip
authors.forename: Lai Wa
authors.initials: LW
authors.lastname: Tse
authors.forename: Oi Chi
authors.initials: OC
authors.lastname: Leung
authors.forename: Lai Ping
authors.initials: LP
authors.lastname: Sin
authors.forename: Mei Yuk
authors.initials: MY
authors.lastname: Chan
authors.forename: Wai Sum
authors.initials: WS
authors.lastname: Wong
mesh_terms: D017677:Age Distribution; D000367:Age Factors; D000995:Antitubercular Agents / Q000494:pharmacology; D018432:Drug Resistance, Multiple / Q000502:physiology*; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D008826:Microbial Sensitivity Tests; D009169:Mycobacterium tuberculosis / Q000187:drug effects / Q000502:physiology*; D012189:Retrospective Studies; D013183:Sputum / Q000382:microbiology*; D014376:Tuberculosis / Q000453:epidemiology / Q000382:microbiology
chemical_list: D000995:Antitubercular Agents