Biomedical subjects

Rui-Heng Xu

Publications and source records attributed to Rui-Heng Xu.

4 recordsLinked to original sources

PubMed2005

Cross-host evolution of severe acute respiratory syndrome coronavirus in palm civet and human.

The genomic sequences of severe acute respiratory syndrome coronaviruses from human and palm civet of the 2003/2004 outbreak in the city of Guangzhou, China, were nearly identical. Phylogenetic analysis suggested an independent viral invasion from animal to human in this new episode. Combining all existing data but excluding singletons, we identified 202 single-nucleotide variations. Among them, 17 are polymorphic in palm civets only. The ratio of nonsynonymous/synonymous nucleotide substitution in palm civets collected 1 yr apart from different geographic locations is very high, suggesting a rapid evolving process of viral proteins in civet as well, much like their adaptation in the human host in the early 2002-2003 epidemic. Major genetic variations in some critical genes, particularly the Spike gene, seemed essential for the transition from animal-to-human transmission to human-to-human transmission, which eventually caused the first severe acute respiratory syndrome outbreak of 2002/2003.

Amino Acid Substitution↗

PubMed2004

Epidemiologic clues to SARS origin in China.

An epidemic of severe acute respiratory syndrome (SARS) began in Foshan municipality, Guangdong Province, China, in November 2002. We studied SARS case reports through April 30, 2003, including data from case investigations and a case series analysis of index cases. A total of 1,454 clinically confirmed cases (and 55 deaths) occurred; the epidemic peak was in the first week of February 2003. Healthcare workers accounted for 24% of cases. Clinical signs and symptoms differed between children (<18 years) and older persons (> or =65 years). Several observations support the hypothesis of a wild animal origin for SARS. Cases apparently occurred independently in at least five different municipalities; early case-patients were more likely than later patients to report living near a produce market (odds ratio undefined; lower 95% confidence interval 2.39) but not near a farm; and 9 (39%) of 23 early patients, including 6 who lived or worked in Foshan, were food handlers with probable animal contact.

Adolescent↗

PubMed2004

[Evaluation of a pilot study on needle and syringe exchange program among injecting drug users in a community in Guangdong, China].

OBJECTIVE: To evaluate the feasibility and effectiveness of needle and syringe exchange program among a community of injecting drug users (IDUs) on AIDS prevention. METHODS: A quasi-experiment design was used in a controlled community intervention study. Needle and syringe exchange program was implemented for 10 months in IDUs of an intervention community, including peer education and health education, provision of free needles and syringes, and collecting back of used needles and syringes by trained peer educators and local health workers, whereas no intervention measure in a control community was instituted. Interviews with IDUs were conducted before and after intervention with a snowballing strategy to evaluate its effectiveness. RESULTS: A total of 428 and 429 IDUs were interviewed with structured questionnaire before and after intervention in intervention and control communities, respectively. Results revealed that awareness of HIV-related knowledge increased from 29.4% to 58.7% in the intervention community. Multivariate logistic regression analysis showed that awareness of HIV-related knowledge was higher in those who had read health education materials (OR = 2.93, 95% CI 2.12 - 4.04). As compared with the baseline data, frequency of sharing needles and syringes in past 30 days in the intervention community decreased from 48.9% to 20.4% in before intervention community (chi(2) = 41.02, P = 0.001), whereas there was no significant change in the control community. The causes of sharing needles and syringes in the intervention community included 'disable to get needle and syringe during the night', 'lack of needle and syringe when injecting at friend's home', 'not daring to buy needle and syringe for fear of being arrested' and 'no money to buy needle and syringe', declined markedly. CONCLUSIONS: Needle and syringe exchange program was feasible and effective in reducing their risky drug injecting behavior among IDUs in communities. Such strategy should be adopted in the country to reduce rapid spread of HIV.

Adult↗

PubMed2003

SARS: epidemiology.

Severe acute respiratory syndrome (SARS) originated in Southern China in November 2002, and was brought to Hong Kong in February 2003. From Hong Kong, the disease spread rapidly worldwide but mostly to Asian countries. At the end of the epidemic in June, the global cumulative total was 8422 cases with 916 deaths (case fatality rate of 11%). People of all ages were affected, but predominantly females. Health care workers were at high risk and accounted for one-fifth of all cases. Risk factors for death included old age and comorbid illnesses, especially diabetes. The disease is caused by a novel coronavirus and is transmitted by droplets or direct inoculation from contact with infected surfaces. Contaminated sewage was found to be responsible for the outbreak in a housing estate in Hong Kong affecting over 300 residents. The mean incubation period was 6.4 days (range 2-10). The duration between onset of symptoms and hospitalisation was from 3 to 5 days. The relatively prolonged incubation period allowed asymptomatic air travellers to spread the disease globally. The number of individuals infected by each case has been estimated to be 2.7. Effective control of nosocomial transmission included early detection of disease, strict isolation of patients, practice of droplet and contact precautions and compliance with the use of personal protective equipment. Effective control of disease spread in the community included tracing and quarantine of contacts. Development of a validated diagnostic test and an effective vaccine as well as elimination of possible animal reservoirs are measures needed to prevent another epidemic.

Adolescent↗