Biomedical subjects

Daniel P Chin

Publications and source records attributed to Daniel P Chin.

7 recordsLinked to original sources

PubMed2004

Laboratory reporting of tuberculosis test results and patient treatment initiation in California.

Prompt laboratory reporting of tuberculosis (TB) test results is necessary for TB control. To understand the extent of and factors contributing to laboratory reporting delays and the impact of reporting delays on initiation of treatment of TB patients, we analyzed data from 300 consecutive culture-positive TB cases reported in four California counties in 1998. Laboratory reporting to the specimen submitter was delayed for 26.9% of smear-positive patients and 46.8% of smear-negative patients. Delays were associated with the type of laboratory that performed the testing and with delayed transport of specimens. Referral laboratories (public health and commercial) had longer median reporting time frames than hospital and health maintenance organization laboratories. Among patients whose treatment was not started until specimens were collected, those with delayed laboratory reporting were more likely to have delayed treatment than patients with no laboratory reporting delays (odds ratio [OR] of 3.9 and 95% confidence interval [CI] of 1.6 to 9.7 for smear-positive patients and OR of 13.1 and CI of 5.3 to 32.2 for smear-negative patients). This relation remained after adjustment in a multivariate model for other factors associated with treatment delays (adjusted OR of 25.64 and CI of 7.81 to 83.33 for smear-negative patients). These findings emphasize the need to reduce times of specimen transfer between institutions and to ensure rapid communication among laboratories, health care providers, and health departments serving TB patients.

Aged↗

PubMed2004

Severe acute respiratory syndrome, Beijing, 2003.

The largest outbreak of severe acute respiratory syndrome (SARS) struck Beijing in spring 2003. Multiple importations of SARS to Beijing initiated transmission in several healthcare facilities. Beijing's outbreak began March 5; by late April, daily hospital admissions for SARS exceeded 100 for several days; 2,521 cases of probable SARS occurred. Attack rates were highest in those 20-39 years of age; 1% of cases occurred in children <10 years. The case-fatality rate was highest among patients >65 years (27.7% vs. 4.8% for those 20-64 years, p < 0.001). Healthcare workers accounted for 16% of probable cases. The proportion of case-patients without known contact to a SARS patient increased significantly in May. Implementation of early detection, isolation, contact tracing, quarantine, triage of case-patients to designated SARS hospitals, and community mobilization ended the outbreak.

Adolescent↗

PubMed2004

Risk factors for SARS among persons without known contact with SARS patients, Beijing, China.

Most cases of severe acute respiratory syndrome (SARS) have occurred in close contacts of SARS patients. However, in Beijing, a large proportion of SARS cases occurred in persons without such contact. We conducted a case-control study in Beijing that compared exposures of 94 unlinked, probable SARS patients with those of 281 community-based controls matched for age group and sex. Case-patients were more likely than controls to have chronic medical conditions or to have visited fever clinics (clinics at which possible SARS patients were separated from other patients), eaten outside the home, or taken taxis frequently. The use of masks was strongly protective. Among 31 case-patients for whom convalescent-phase (>21 days) sera were available, 26% had immunoglobulin G to SARS-associated coronavirus. Our finding that clinical SARS was associated with visits to fever clinics supports Beijing's strategy of closing clinics with poor infection-control measures. Our finding that mask use lowered the risk for disease supports the community's use of this strategy.

Adolescent↗

PubMed2004

Superspreading SARS events, Beijing, 2003.

Superspreading events were pivotal in the global spread of severe acute respiratory syndrome (SARS). We investigated superspreading in one transmission chain early in Beijing's epidemic. Superspreading was defined as transmission of SARS to at least eight contacts. An index patient with onset of SARS 2 months after hospital admission was the source of four generations of transmission to 76 case-patients, including 12 healthcare workers and several hospital visitors. Four (5%) case circumstances met the superspreading definition. Superspreading appeared to be associated with older age (mean 56 vs. 44 years), case fatality (75% vs. 16%, p = 0.02, Fisher exact test), number of close contacts (36 vs. 0.37) and attack rate among close contacts (43% vs. 18.5%, p < 0.025). Delayed recognition of SARS in a hospitalized patient permitted transmission to patients, visitors, and healthcare workers. Older age and number of contacts merit investigation in future studies of superspreading.

Adult↗

PubMed2003

Evaluation of control measures implemented in the severe acute respiratory syndrome outbreak in Beijing, 2003.

CONTEXT: Beijing, China, experienced the world's largest outbreak of severe acute respiratory syndrome (SARS) beginning in March 2003, with the outbreak resolving rapidly, within 6 weeks of its peak in late April. Little is known about the control measures implemented during this outbreak. OBJECTIVE: To describe and evaluate the measures undertaken to control the SARS outbreak. DESIGN, SETTING, AND PARTICIPANTS: Data were reviewed from standardized surveillance forms from SARS cases (2521 probable cases) and their close contacts observed in Beijing between March 5, 2003, and May 29, 2003. Procedures implemented by health authorities were investigated through review of official documents and discussions with public health officials. MAIN OUTCOME MEASURES: Timeline of major control measures; number of cases and quarantined close contacts and attack rates, with changes in infection control measures, management, and triage of suspected cases; and time lag between illness onset and hospitalization with information dissemination. RESULTS: Health care worker training in use of personal protective equipment and management of patients with SARS and establishing fever clinics and designated SARS wards in hospitals predated the steepest decline in cases. During the outbreak, 30 178 persons were quarantined. Among 2195 quarantined close contacts in 5 districts, the attack rate was 6.3% (95% confidence interval [CI], 5.3%-7.3%), with a range of 15.4% (95% CI, 11.5%-19.2%) among spouses to 0.36% (95% CI, 0%-0.77%) among work and school contacts. The attack rate among quarantined household members increased with age from 5.0% (95% CI, 0%-10.5%) in children younger than 10 years to 27.6% (95% CI, 18.2%-37.0%) in adults aged 60 to 69 years. Among almost 14 million people screened for fever at the airport, train stations, and roadside checkpoints, only 12 were found to have probable SARS. The national and municipal governments held 13 press conferences about SARS. The time lag between illness onset and hospitalization decreased from a median of 5 to 6 days on or before April 20, 2003, the day the outbreak was announced to the public, to 2 days after April 20 (P<.001). CONCLUSIONS: The rapid resolution of the SARS outbreak was multifactorial, involving improvements in management and triage in hospitals and communities of patients with suspected SARS and the dissemination of information to health care workers and the public.

China↗

PubMed2002

The global tuberculosis situation. Progress and problems in the 20th century, prospects for the 21st century.

Mycobacterium tuberculosis has been identified in prehistoric remains of humans. Despite references to TB by Hippocrates and Galen, humankind had limited understanding of and few tools to defend itself against TB until the later 19th century. Subsequently, landmark advances in the 20th century provided the means to control and prevent this disease. At the same time, epidemiological developments and fundamental problems related to human behavior, socioeconomic conditions, and political circumstances continue to thwart efforts to diminish the burden of suffering and death caused by TB. This article reviewed some of these issues including the global failure of TB control in the late 20th century, the worldwide emergence of drug-resistant TB, the extensive spread of HIV infection and its impact on TB incidence; and changing health care and political environments. The obstacles to TB control remain and will remain challenges in the coming years. Still, recent developments in immunology, biochemistry, and molecular biology suggest that new knowledge and tools are just around the corner. These will enhance the ability to conquer this microbe by the end of the current century.

HIV Infections↗

PubMed2002

The DOTS strategy in China: results and lessons after 10 years.

OBJECTIVE: To analyse the five-point tuberculosis (TB) strategy, DOTS, 10 years after its implementation in one-half of China's population, and to suggest lessons for future implementation of the DOTS strategy. METHODS: We analysed trends in case-finding and treatment outcome over time following implementation of the DOTS strategy in each county, using routine reporting data from the Infectious and Endemic Disease Control (IEDC) project (1991 - 2000). We also determined the proportion of counties with different levels of case-finding for the fifth and sixth years of DOTS implementation. FINDINGS: From 1991 to 1995, DOTS expanded rapidly to cover more than 90% of target population and counties. By 2000, 8 million TB suspects had received free diagnostic evaluation: 1.8 million TB cases were diagnosed, free treatment was provided to 1.3 million smear-positive cases, and more than 90% were cured. During DOTS implementation, the percentage of previously treated cases decreased among all smear-positive cases and treatment outcomes improved. Despite these achievements, the detection rate for new smear-positive cases in the project was estimated to be only 54% in 1998, and 41.2% of the counties had a below average or low level of case-finding (with substantial variation between provinces). CONCLUSIONS: The IEDC project demonstrated that it is feasible to rapidly expand DOTS on a large scale. The global target of an 85% cure rate was quickly achieved, and the level of drug-resistance was probably reduced by this project. However, case-detection did not reach the 70% global target, and more research is needed on how to enhance this.

Antitubercular Agents↗