Stability of hepatitis B viral load during pregnancy and implications for antepartum prophylaxis: A prospective cohort study.

BACKGROUND: We examined changes in hepatitis B virus (HBV) viral loads (VLs) in pregnancy, their association with hepatitis B e antigen (HBeAg), and the associated infant outcomes. METHODS: We prospectively followed 132 mothers positive for hepatitis B surface antigen (HBsAg) and their 135 infants from 2011 to 2015 in Vancouver, British Columbia. Outcome measures included association between maternal HBeAg and high (>200,000 IU/mL) or low (≤200,000 IU/mL) HBV VL, changes in HBV VL through pregnancy, infant HBsAg status, and infant completion of the HBV vaccination series. RESULTS: f the 91 participants with an available HBV VL, 13 (14.3%) had an HBV VL of more than 200,000 IU/mL. Of 59 participants with paired HBeAg and HBV VL in pregnancy, 6 had an HBV VL of more than 200,000 IU/mL; of interest, 2 of the 6 (33.3%) were HBeAg-negative. Thirty-eight participants had HBV VL results at both mid-trimester and delivery. For these 38 participants, Wilcoxon signed-ranks test for paired data found that an HBV VL remained stable (p = .58). We observed no perinatal transmissions. However, 20.7% of infants did not have a documented complete HBV vaccination series, 20.0% did not have post-vaccination HBsAg testing completed, and 18% did not have anti-HBs titres measured by age 12 months. CONCLUSIONS: Our study demonstrates that HBeAg and HBV VL are not reliably predictive of each other. This supports the improved predictive value of VL measurement in pregnancy to risk stratify pregnant patients to offer antiviral treatment when indicated and further minimize the risk of perinatal transmission.

Notes from the Field: Furanyl-Fentanyl Overdose Events Caused by Smoking Contaminated Crack Cocaine - British Columbia, Canada, July 15-18, 2016.

On July 15 2016, Surrey Memorial Hospital's emergency department notified the medical health officer on call of a sharp increase in opioid overdose events in Surrey, Fraser Health Authority, in British Columbia, Canada. During July 15-18, the number of persons with suspected opioid overdose evaluated in Surrey Memorial Hospital's emergency department increased approximately 170%, from an average of four suspected cases per day during the period January-June 2016 to 43 (nearly 11 per day) during the 4-day period (Figure). Most patients (22 [51%]) became unconscious after smoking what they believed to be crack cocaine. The majority of overdose events occurred within a small geographic area in Surrey that has a high population of homeless persons and persons who use illicit drugs, including opioids and crack cocaine. Most cases occurred in males (36 cases [84%]); the average age of the patients was 42 years (range = 18-63 years). Forty (93%) patients were brought to the emergency department by ambulance. A total of 37 (86%) patients received injectable naloxone before arriving in the emergency department, including 12 who received it only from community members, 16 who received it only from paramedics, five who received it from both community members and paramedics, one who received it from the fire department and paramedics, and one who received it from the fire department, community, and paramedics; for two patients, the source of naloxone was not known. Reports from first responders, the community, and emergency department staff members indicated that patients required high doses of injectable naloxone, in some cases up to 3.0 mg (usual dose = 0.4 mg). Thirty-five (81%) patients were treated and discharged within a few hours, two patients left without being seen by a health care provider, and six patients were admitted to the hospital; among these, three were transferred to the intensive care unit, one of whom died.

Epidemiologic and Genotypic Review of Carbapenemase-Producing Organisms in British Columbia, Canada, between 2008 and 2014.

Carbapenemase-producing organisms (CPOs) are a serious emerging problem for health care facilities worldwide. Owing to their resistance to most antimicrobial therapies, CPOs are difficult to treat and pose a challenge for infection prevention and control. Since 2010, lab-based surveillance for CPOs and PCR-based testing were implemented in British Columbia (BC), Canada. A review of CPOs in BC from 2008 to March 2014 was done to characterize the resistance mechanisms and possible clonal strain transmission and to compare pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and plasmid restriction fragment length polymorphism (RFLP) as molecular typing tools. During this study period, a total of 177 CPO cases were identified. Patient demographics and travel history were reviewed, and a descriptive analysis was carried out. PFGE profiles, MLST, and plasmid RFLP analysis for a subset of Escherichia coli, Klebsiella pneumoniae, and Enterobacter species isolates were obtained and analyzed. Our findings demonstrate that CPOs have been increasing in number in BC over time, from 1 isolate/year retrospectively identified in 2008 and 2009 to 82 isolates in 2013 and 30 isolates in the first quarter of 2014. Overall, K. pneumoniae isolates lack clonality, although some seemingly related clusters have been found. Plasmid analysis showed evidence of the spread of plasmids carrying carbapenemase-encoding genes between the examined isolates. Analysis of Enterobacter cloacae isolates revealed a more clonal nature of these CPOs in BC. The presence of related clusters provides evidence of interpatient organism transmission both within and between institutions. Although in our study, NDM-harboring E. cloacae isolates appeared to spread clonally, the spread of carbapenem resistance in K. pneumoniae seems to be plasmid mediated.

Missed opportunities for prevention of perinatal transmission of hepatitis B: a retrospective cohort study.

BACKGROUND: Perinatal transmission of hepatitis B virus (HBV) can occur despite postexposure prophylaxis (PEP). Recent literature suggests that antiviral treatment during pregnancy when maternal HBV DNA levels are elevated can further decrease vertical transmission. However, HBV DNA screening is not routinely performed antenatally. OBJECTIVE: To determine the rates of HBV prevalence and perinatal transmission in an antenatal cohort. METHODS: A retrospective review of public health records (December 2008 to December 2010) was performed for both mothers and newborns. RESULTS: A total of 725 mother-infant pairs were included. Of these, 574 of 715 (80%) women had antenatal hepatitis B e antigen (HBeAg) testing performed, and 127 of 574 (22%) were HBeAg positive (HBeAg+). Of babies born to hepatitis B surface antigen-positive (HBsAg+) mothers, only 573 of 725 (79%) received complete PEP. In addition, 172 of 725 (24%) infants did not receive post-PEP blood testing or were lost to follow-up. Of the 552 infants with results available, seven cases (1.3%) of mother-to-child HBV transmission were observed, six of which involved infants born to HBeAg+ women. CONCLUSIONS: Our findings suggest that routine HBeAg screening could identify a subset of mother-infant pairs among HBsAg+ pregnant women who are at higher risk for vertical HBV transmission. Determination of viral load in expectant HBeAg+ mothers may provide more precise insight into HBV transmission to their infants.

Whole-genome sequencing and social-network analysis of a tuberculosis outbreak.

BACKGROUND: An outbreak of tuberculosis occurred over a 3-year period in a medium-size community in British Columbia, Canada. The results of mycobacterial interspersed repetitive unit-variable-number tandem-repeat (MIRU-VNTR) genotyping suggested the outbreak was clonal. Traditional contact tracing did not identify a source. We used whole-genome sequencing and social-network analysis in an effort to describe the outbreak dynamics at a higher resolution. METHODS: We sequenced the complete genomes of 32 Mycobacterium tuberculosis outbreak isolates and 4 historical isolates (from the same region but sampled before the outbreak) with matching genotypes, using short-read sequencing. Epidemiologic and genomic data were overlaid on a social network constructed by means of interviews with patients to determine the origins and transmission dynamics of the outbreak. RESULTS: Whole-genome data revealed two genetically distinct lineages of M. tuberculosis with identical MIRU-VNTR genotypes, suggesting two concomitant outbreaks. Integration of social-network and phylogenetic analyses revealed several transmission events, including those involving "superspreaders." Both lineages descended from a common ancestor and had been detected in the community before the outbreak, suggesting a social, rather than genetic, trigger. Further epidemiologic investigation revealed that the onset of the outbreak coincided with a recorded increase in crack cocaine use in the community. CONCLUSIONS: Through integration of large-scale bacterial whole-genome sequencing and social-network analysis, we show that a socioenvironmental factor--most likely increased crack cocaine use--triggered the simultaneous expansion of two extant lineages of M. tuberculosis that was sustained by key members of a high-risk social network. Genotyping and contact tracing alone did not capture the true dynamics of the outbreak. (Funded by Genome British Columbia and others.).

Lead and mercury exposures: interpretation and action.

Lead and mercury are naturally occurring elements in the earth's crust and are common environmental contaminants. Because people concerned about possible exposures to these elements often seek advice from their physicians, clinicians need to be aware of the signs and symptoms of lead and mercury poisoning, how to investigate a possible exposure and when intervention is necessary. We describe 3 cases of patients who presented to an occupational medicine specialist with concerns of heavy metal toxicity. We use these cases to illustrate some of the issues surrounding the investigation of possible lead and mercury exposures. We review the common sources of exposure, the signs and symptoms of lead and mercury poisoning and the appropriate use of chelation therapy. There is a need for a clear and consistent guide to help clinicians interpret laboratory investigations. We offer such a guide, with information about population norms, lead and mercury levels that suggest exposure beyond that seen in the general population and levels that warrant referral for advice about clinical management.

Impact of HAART and injection drug use on life expectancy of two HIV-positive cohorts in British Columbia.

BACKGROUND: The introduction of HAART has led to consistent improvements in survival among HIV-infected individuals. However, there is evidence that not all populations have benefited equally from HAART and that mortality rates are higher in HIV-infected injection drug users than in non-users. OBJECTIVE: To model life expectancies for HIV-positive individuals subdivided according to history of injection drug use and treatment with HAART. DESIGN: Population-based study of HIV-positive persons in British Columbia's HIV/AIDS treatment program. METHODS: The primary outcome measures in this study were life expectancy at exact age 20 and potential years of life lost. RESULTS: The highest life expectancy (38.9 years) and lowest potential years of life lost were measured for individuals taking HAART and without a history of injection drug use. The lowest life expectancy (19.1 years) and highest potential years of life lost were measured in HIV-positive injection drug users who were not taking HAART. CONCLUSIONS: There are substantial disparities in life expectancy for persons living with HIV in British Columbia. Members of the injection drug community, particularly those who are not taking HAART, experience elevated mortality in comparison with those without a history of drug use.