Exploring tuberculosis by types of housing development.

Tuberculosis (TB) is known as a disease of poverty. It has also been related to poor living environment. This study examines the relationship between TB outcome and housing characteristics which is reflective of the socio-economic standing. We sought to investigate the association from two novel angles: (1) TB outcome against floor level of residence, and (2) TB outcome against types of housing development. A total of 1787 culture-positive TB cases were collected by the Centralized Mycobacterium Laboratory from 2007 to 2009. Most of the cases fell in the catchment area of the Kowloon West Cluster, a densely populated urban area in Hong Kong. The distribution of culture-positive TB cases by floor levels of residence and types of housing was examined by descriptive and non-parametric statistical analyses. The effects of vertical distance of residence from the street level on TB outcome by different types of housing development were further explored by regression methods. Our study confirmed more TB cases among tenants on the lower floors and observed a decreasing trend towards higher floors. It also revealed that significantly more TB cases were residing in public as opposed to private or other types of housing (Chi-square = 151.14, p < 0.0001). Regression analysis by different housing types showed significantly different rates of change between floor number and TB cases (p < 0.0001). Our findings offer evidence on the inverse associations between floor levels of residence and TB occurrences and showed that the patterns were dependent on housing types. We demonstrated how housing characteristics could be useful input in an ecological study of the TB disease. These results have significant design and health implications for Asian cities that are getting denser and growing taller.

A comparative study of clinical features and outcomes in young and older adults with severe acute respiratory syndrome.

OBJECTIVES: To determine the clinical presentation, findings, and outcomes of older adults (> 60) with severe acute respiratory syndrome (SARS) and compare these with a control group of younger patients (< or or =60). DESIGN: Retrospective cohort study. SETTING: A community-based, acute hospital in Hong Kong. PARTICIPANTS: All adult inpatients with a clinical diagnosis of SARS. MEASUREMENTS: Clinical presentations, investigations, treatment, and 30- and 150-day mortality. RESULTS: There were 52 young and 25 older patients with a mean age +/- standard deviation of 39.5+/-11.7 and 72.1+/-7.2, respectively. Fever, chills, and diarrhea were more common in younger patients, whereas decrease in appetite and general condition occurred only in older patients. The prevalence of positive reverse-transcriptase polymerase chain reaction for SARS-associated coronavirus (SARS-CoV) in nasopharyngeal secretions and stool samples was similar in the two groups. The prevalence of positive serological tests for SARS-CoV was significantly lower in older patients (42% vs 92%, P<.001). This was largely due to incomplete testing in elderly patients. Older patients were more likely to develop secondary nosocomial infection, be admitted to an intensive care unit, and require mechanical ventilation. The cumulative 30- and 150-day mortality rates were 3.8% and 7.6%, respectively, in young patients with SARS and 56% and 60%, respectively, in older patients (P<.001). CONCLUSION: Older patients with SARS more often presented with nonspecific symptoms, and the prognosis was poor. Reverse-transcriptase polymerase chain reaction was useful in diagnosing SARS in older patients, but the role of serological tests in individual elderly is limited.