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Michael L Rekart

Publications and source records attributed to Michael L Rekart.

11 recordsLinked to original sources
PubMed2006

A population-based approach to determine the prevalence of transmitted drug-resistant HIV among recent versus established HIV infections: results from the Canadian HIV strain and drug resistance surveillance program.

OBJECTIVES: Published results on primary or transmitted HIV drug resistance may be biased because they have been largely derived from specific cohort studies or higher risk individuals who present symptomatically. Here, we present results from a representative population-based study of newly diagnosed cases of HIV in Canada and compare the prevalence of transmitted drug resistance between recent and established infections. METHODS: Available archived sera taken for the purpose of diagnostic HIV testing from all treatment-naive HIV-positive individuals who were newly diagnosed between 2000 and 2001 were tested for recency of infection, HIV-1 subtype, and mutations conferring reduced susceptibility to reverse transcriptase inhibitors and protease inhibitors (PIs). Recent infections were identified using the Organon Teknika Vironostika HIV-1-LS assay. After full-length sequencing of the pol gene, drug resistance mutations were identified using the 2004 International AIDS Society-USA mutations panel. Differences in drug resistance profiles between recent and prevalent infections were examined using the chi test and the Fisher exact test. The variables examined included gender, age at diagnosis, year of diagnosis, exposure category, ethnicity, and HIV-1 subtype. RESULTS: Among the study population, 8.1% had genotypic evidence of transmitted drug resistance: 4.1% against nucleoside reverse transcriptase inhibitors, 1.4% against nonnucleoside reverse transcriptase inhibitors, 1.5% against PIs, and 1% against > or =2 classes of drugs. A higher proportion of recent infections had genotypic evidence of transmitted drug resistance when compared with established infections (12.2% vs. 6.1%, respectively; P = 0.005). Transmitted drug resistance was identified mainly among recently infected Caucasian men who have sex with men but it was not limited to this group. Compared with the year 2000, a higher proportion of recently infected individuals with resistance-conferring mutations were diagnosed during the year 2001 (66.7% vs. 46.6%). CONCLUSIONS: In Canada, transmitted drug resistance is occurring within all 3 drug classes and across different population groups. The results suggest that the prevalence rates may be higher among recent versus established infections. Given the public health implications of transmitting drug-resistant HIV, it is important to continue population-based drug resistance surveillance to guide optimum prevention and treatment of HIV infection.

Adult↗
PubMed2005

Sex-work harm reduction.

Sex work is an extremely dangerous profession. The use of harm-reduction principles can help to safeguard sex workers' lives in the same way that drug users have benefited from drug-use harm reduction. Sex workers are exposed to serious harms: drug use, disease, violence, discrimination, debt, criminalisation, and exploitation (child prostitution, trafficking for sex work, and exploitation of migrants). Successful and promising harm-reduction strategies are available: education, empowerment, prevention, care, occupational health and safety, decriminalisation of sex workers, and human-rights-based approaches. Successful interventions include peer education, training in condom-negotiating skills, safety tips for street-based sex workers, male and female condoms, the prevention-care synergy, occupational health and safety guidelines for brothels, self-help organisations, and community-based child protection networks. Straightforward and achievable steps are available to improve the day-to-day lives of sex workers while they continue to work. Conceptualising and debating sex-work harm reduction as a new paradigm can hasten this process.

Delivery of Health Care↗
PubMed2005

The unexpected impact of a Chlamydia trachomatis infection control program on susceptibility to reinfection.

BACKGROUND: After the introduction of a program to control Chlamydia trachomatis infection in British Columbia, Canada, case rates fell from 216 cases/100,000 population in 1991 to 104 cases/100,000 population in 1997. Since 1998, rates have increased, and case counts now exceed those recorded before the intervention. METHODS: We used Cox proportional-hazards survival analysis and developed a compartmental mathematical model to investigate the cause of resurgence in chlamydia cases. RESULTS: Cox proportional-hazards survival analysis showed that the relative risk of C. trachomatis reinfection has increased 4.6% per year since 1989, with the increased risk greatest among the young and greater among women than men. A compartmental mathematical model of C. trachomatis transmission showed that a control strategy based on shortening the average duration of infection results in an early reduction in prevalence followed by a rebound in prevalence, reproducing the observed trends. CONCLUSIONS: We speculate that a C. trachomatis infection control program based on early case identification and treatment interferes with the effects of immunity on population susceptibility to infection and that, in the absence of strategies to alter sexual networks, a vaccine will be needed to halt the spread of infection at the population level.

Adolescent↗
PubMed2005

Prenatal and congenital syphilis in British Columbia.

OBJECTIVE: To describe the incidence of maternal syphilis and the corresponding rate of infection in exposed neonates in British Columbia before and after a serious outbreak of infectious syphilis in the heterosexual population. METHODS: We conducted a retrospective chart review of pregnant women with positive syphilis serology and reported cases of congenital syphilis in British Columbia from 1994 to 2003. Clinical charts were reviewed for demographic information, staging of maternal syphilis, and stage of pregnancy when treatment was received. The primary outcome measure was the number of cases of congenital syphilis. We conducted a 2-sided z-test and Fisher's exact test to determine differences in the proportion of infectious syphilis in mothers and the number of cases of congenital syphilis before and during the major outbreak. RESULTS: In 389 478 live births in British Columbia between 1994 and 2003, 77% of mothers had prenatal syphilis serology. A diagnosis of syphilis was made in 183 mothers, resulting in 5 cases of congenital syphilis. Four of these were in infants whose mothers did not undergo prenatal syphilis testing. The proportion of pregnant women with infectious syphilis was significantly higher after the onset of a major outbreak of syphilis in the community than it was before (P = 0.001), but there was no significant difference in the number of cases of congenital syphilis (3 before and 2 after the outbreak, P = 0.36). CONCLUSION: Although syphilis rates in British Columbia during the study period rose steadily, the prevalence of congenital syphilis remained low. Our findings suggest that, in the context of a major outbreak, universal screening and prenatal syphilis testing may contribute to controlling rates of congenital syphilis.

Adult↗
PubMed2005

The impact of syphilis mass treatment one year later: self-reported behaviour change among participants.

In 2000, syphilis mass treatment using oral azithromycin was delivered to at-risk British Columbians during a sex trade-related outbreak. The initiative included education, counselling and referral. This cross-sectional, observational study examines knowledge, attitudes and self-reported behaviour after one year among mass treatment participants compared with eligible non-participants. Participants self-reported positive changes: reduction in sexual partners overall (P=0.001) and for sex workers (P<0.01), decrease in unprotected oral sex (P=0.03), knowledge of asymptomatic syphilis (P=0.02), positive attitudes to mass treatment (P=0.02) and to the street nurses (P=0.01). Increased awareness was associated with increased condom use for vaginal sex overall (P=0.02) and for sex workers (P=0.03) and increased condom use for oral sex (P=0.05). There was no difference in syphilis incidence. Syphilis outbreak interventions that include education, support and referral can result in long-term positive behaviour changes.

Adolescent↗
PubMed2003

Targeted mass treatment for syphilis with oral azithromycin.

From mid 1997 to end of 1999, there was a sexually-transmitted infectious syphilis outbreak mainly in heterosexual people in British Columbia, Canada, that was concentrated in Vancouver. The rate across the province increased from less than 0.5 to 3.4 per 100000, and the rate in Vancouver reached 12.9 per 100000. We aimed to eliminate the syphillis outbreak by treating people at risk of infection. In 2000, a targeted mass treatment programme provided azithromycin (1.8 g orally) to 4384 at-risk residents in this city. After the programme, syphilis frequency fell significantly for 6 months (p=0.016), but rose again in 2001. Results from curve fitting analyses showed that the number of cases in 2001 (177) was higher than expected (0.0001<p<0.0044). This rate rebound and the absence of a sustained effect suggest that targeted mass treatment for syphilis, even though feasible, should not be done routinely.

Adolescent↗
PubMed2003

Impact of mass treatment on syphilis transmission: a mathematical modeling approach.

BACKGROUND: Since 1997 Vancouver (British Columbia, Canada) has experienced an outbreak of heterosexually transmitted infectious syphilis, which prompted a mass treatment campaign in early 2000 in an attempt to control the disease. By 1 year postintervention, syphilis cases had rebounded significantly. We investigate the cause of this postintervention rebound. GOAL: We argue that the observed rebound postintervention may have been the result of the natural dynamics of disease transmission in an open population, in response to the partial application of mass treatment in the sexually active subgroup. STUDY DESIGN: We used a mathematical model that describes the transmission dynamics of syphilis in a population. RESULTS: The observed postintervention rebound is related to the mass treatment intervention. CONCLUSION: Our results suggest that mass treatment may not be an optimal strategy to control the transmission of syphilis if complete coverage of high-frequency transmitters cannot be achieved and if population mobility is relatively high.

Adolescent↗
PubMedDate not supplied

The influence of prevalence and policy on the likelihood that a physician will offer HIV screening in pregnancy.

OBJECTIVE: To determine the extent to which provincial recommendations, reported regional prevalence rates and perceived local prevalence rates of HIV in pregnancy influence a physician's decision to routinely offer prenatal screening for HIV. DESIGN AND METHODS: A random sample of 5,052 family physicians and obstetricians were surveyed by mail. Logistic regression was used to explore the relationships among the variables of interest. RESULTS: The response rate was 61%. Of these, 69.2% provided prenatal care and were included in the analysis. Physicians were more likely to routinely offer HIV testing if they practiced in provinces with recommendations that supported the universal offer of a test (O.R. = 5.80), independent of living in a region with an estimated prevalence rate exceeding 5/10,000 (O.R. = 1.76), or the perception that the infection rate in their practice justified universal counselling of pregnant women (O.R. = 10.41). CONCLUSIONS: Provincial recommendations supporting universal HIV testing in pregnancy are reflected in physician practice.

AIDS Serodiagnosis↗