Deanne Langlois-Klassen

Who's talking? Communication between health providers and HIV-infected adults related to herbal medicine for AIDS treatment in western Uganda.

Communication between patients and physicians about herbal medicine is valuable, enabling physicians to address issues of potential herb-drug interactions and ensuring appropriate medical care. As seemingly harmless herbal remedies may have detrimental interactions with various HIV antiretroviral drugs, the importance of communication is intensified, but often stifled around the use of herbal medicine in the treatment of HIV/AIDS. In western Uganda, 137 HIV-infected adults attending conventional HIV/AIDS treatment programmes (67 of whom were receiving antiretroviral therapy) shared their experiences and perceptions about traditional herbal medicine and related patient-physician communication issues through interviews and focus group discussions. Although close to 64% of respondents reported using herbal medicine after being diagnosed with HIV, only 16% of these respondents had informed their conventional medical practitioners about using these herbs. Furthermore, only 13% of antiretroviral therapy recipients had inquired about concurrent herb-antiretroviral drug use with their HIV/AIDS treatment providers, largely because they perceived a low acceptance and support for herbal medicine by conventional medical practitioners. Importantly however, almost 68% of HIV-infected adults indicated they would be willing to discuss herbal medicine use if directly asked by a conventional medical practitioner, and the overwhelming majority (91%) said they were amenable to following physician advice about herbal medicine. As such, improved patient-physician communication about herbal medicine is needed, and we recommend that herbal medicine histories be completed when patient histories are taken. Also, HIV/AIDS treatment programmes should be encouraged to develop specific patient-physician communication standards and best practice guidelines to ensure that patients can make informed decisions about herb and pharmaceutical drug co-therapy based on known risks, particularly in the case of AIDS patients receiving antiretroviral therapy. Communication about herbal medicine usage should be viewed as a timely and cost-effective component of antiretroviral therapy programmes, one which may contribute to the overall success of AIDS treatment in Africa.

Dispersal of Mycobacterium tuberculosis via the Canadian fur trade

Patterns of gene flow can have marked effects on the evolution of populations. To better understand the migration dynamics of Mycobacterium tuberculosis, we studied genetic data from European M. tuberculosis lineages currently circulating in Aboriginal and French Canadian communities. A single M. tuberculosis lineage, characterized by the DS6Quebec genomic deletion, is at highest frequency among Aboriginal populations in Ontario, Saskatchewan, and Alberta; this bacterial lineage is also dominant among tuberculosis (TB) cases in French Canadians resident in Quebec. Substantial contact between these human populations is limited to a specific historical era (1710–1870), during which individuals from these populations met to barter furs. Statistical analyses of extant M. tuberculosis minisatellite data are consistent with Quebec as a source population for M. tuberculosis gene flow into Aboriginal populations during the fur trade era. Historical and genetic analyses suggest that tiny M. tuberculosis populations persisted for ∼100 y among indigenous populations and subsequently expanded in the late 19th century after environmental changes favoring the pathogen. Our study suggests that spread of TB can occur by two asynchronous processes: (i) dispersal of M. tuberculosis by minimal numbers of human migrants, during which small pathogen populations are sustained by ongoing migration and slow disease dynamics, and (ii) expansion of the M. tuberculosis population facilitated by shifts in host ecology. If generalizable, these migration dynamics can help explain the low DNA sequence diversity observed among isolates of M. tuberculosis and the difficulties in global elimination of tuberculosis, as small, widely dispersed pathogen populations are difficult both to detect and to eradicate.

The tuberculin skin test is unreliable in school children BCG-vaccinated in infancy and at low risk of tuberculosis infection.

Background: The tuberculin skin test (TST) is often used to screen for latent tuberculosis infection (LTBI) in school children, many of whom were bacille Calmette-Guérin (BCG)-vaccinated in infancy. The reliability of the TST in such children is unknown. Methods: TSTs performed in low-risk BCG-vaccinated and -nonvaccinated grade 1 and grade 6 First Nations (North American Indian) school children in the province of Alberta, Canada, were evaluated retrospectively. To further assess the specificity of the TST, BCG-vaccinated children with a positive TST (≥10 mm of induration) and no treatment of LTBI were administered a QuantiFERON-TB Gold In-Tube test (QFT-GIT, Cellestis International). Results: A total of 3996 children, 2063 (51.6%) BCG-vaccinated and 1933 (48.4%) BCG-nonvaccinated, were screened for LTBI. Vaccinated children were more likely than nonvaccinated children to be TST positive (5.7% vs. 0.2%, P < 0.001). Vaccinated children with a positive TST were more likely to have a recent past TST as compared with those with a negative TST (6.8% versus 2.8%, P = 0.01). Among 65 BCG-vaccinated TST-positive children who underwent a QFT-GIT, only 5 (7.7%; 95% CI: 2.5%, 17.0%) were QFT-GIT positive. A TST of ≥15 mm was more likely to be associated with a positive QFT-GIT than a TST of 10 to 14 mm, 16.0% (95% CI: 4.5%, 36.1%) versus 2.5% (95% CI: 0.1%, 13.2%), P = 0.047. Conclusion: The TST is unreliable in school children, BCG-vaccinated in infancy, and who are at low risk of infection. The QFT-GIT is a useful confirmatory test for LTBI in BCG-vaccinated TST-positive school children.

Transmission of Mycobacterium tuberculosis Beijing Strains, Alberta, Canada, 1991–2007

Transmission of Beijing strains posed no more of a public health threat than did non-Beijing strains.

A population-based cohort study of Mycobacterium tuberculosis Beijing strains: an emerging public health threat in an immigrant-receiving country?

Introduction Mycobacterium tuberculosis Beijing strains are frequently associated with tuberculosis outbreaks and drug resistance. However, contradictory evidence and limited study generalizability make it difficult to foresee if the emergence of Beijing strains in high-income immigrant-receiving countries poses an increased public health threat. The purpose of this study was to determine if Beijing strains are associated with high risk disease presentations relative to other strains within Canada. Methods This was a retrospective population-based study of culture-confirmed active TB cases in a major immigrant-receiving province of Canada in 1991 through 2007. Of 1,852 eligible cases, 1,826 (99%) were successfully genotyped. Demographic, clinical, and mycobacteriologic surveillance data were combined with molecular diagnostic data. The main outcome measures were site of disease, lung cavitation, sputum smear positivity, bacillary load, and first-line antituberculosis drug resistance. Results A total of 350 (19%) patients had Beijing strains; 298 (85%) of these were born in the Western Pacific. Compared to non-Beijing strains, Beijing strains were significantly more likely to be associated with polyresistance (aOR 1.8; 95% CI 1.0–3.3; p = 0.046) and multidrug-resistance (aOR 3.4; 1.0–11.3; p = 0.049). Conversely, Beijing strains were no more likely than non-Beijing strains to be associated with respiratory disease (aOR 1.3; 1.0–1.8; p = 0.053), high bacillary load (aOR 1.2; 0.6–2.7), lung cavitation (aOR 1.0; 0.7–1.5), immediately life-threatening forms of tuberculosis (aOR 0.8; 0.5–1.6), and monoresistance (aOR 0.9; 0.6–1.3). In subgroup analyses, Beijing strains only had a significant association with multidrug-resistant tuberculosis (aOR 6.1; 1.2–30.4), and an association of borderline significance with polyresistant tuberculosis (aOR 1.8; 1.0–3.5; p = 0.062), among individuals born in the Western Pacific. Conclusion Other than an increased risk of polyresistant or multidrug-resistant tuberculosis, Beijing strains appear to pose no more of a public health threat than non-Beijing strains within a high-income immigrant-receiving country.

A clinical opportunity for routine HIV testing

Thank you for publishing the editorial “Seek and Treat to Optimize HIV and AIDS Prevention.”[1][1] This article raises a number of important points about HIV screening but unfortunately contains a significant error. That “Canada has no recommendation for routine [HIV] testing outside of

Towards the elimination of paediatric tuberculosis in high-income, immigrant-receiving countries: a 25-year conventional and molecular epidemiological case study

The epidemiology of tuberculosis (TB) in high-income countries is increasingly dictated by immigration. The influence of this trend on paediatric TB and TB elimination are not well defined. We undertook a 25-year conventional and molecular epidemiologic study of paediatric TB in Alberta, one of four major immigrant-receiving provinces in Canada. All isolates of Mycobacterium tuberculosis were DNA fingerprinted using standard methodology. Between 1990 and 2014, 176 children aged 0–14 years were diagnosed with TB. Foreign-born children or Canadian-born children of foreign-born parents accounted for an increasingly large proportion of total cases during the study period (from 32.1% to 89.5%). Of the 78 culture-positive cases, 35 (44.9%) had a putative source case identified by conventional epidemiology, with 34 (97.1%) having a concordant molecular profile. Of the remaining 43 culture-positive cases, molecular profiling identified spatially and temporally related sources in six cases (14.0%). These six children, along with four other children whose source cases were discovered through reverse-contact tracing, had a high morbidity and mortality. The increasing burden of paediatric TB in both foreign-born children and Canadian-born children of foreign-born parents calls for more timely diagnosis of source cases and more targeted screening for latent TB infection. Conventional and molecular epidemiology can inform paediatric TB elimination strategy in high-income countries http://ow.ly/mwbn30iY1WF