Outbreak of acute hepatitis B virus infection associated with exposure to acupuncture.

BACKGROUND: The most common risk factors for acute hepatitis B virus (HBV) infection are sexual contact, injection drug use and perinatal, or nosocomial exposure. Acupuncture, used in China for over 2,500 years, has been gaining popularity as an alternative medical therapy in the western world, but when associated with poor infection control practices, is also a risk for blood-borne infections. OBJECTIVE: To describe the outbreak investigation following detection of two cases of acute HBV infection associated with acupuncture services from the same provider within four months of symptom onset. METHODS: The outbreak investigation included genotyping of HBV from the identified cases, on-site assessment of the acupuncturist's infection prevention and control practices and chart review of known clients. RESULTS: Both cases had HBV genotype D1 with an identical fingerprint and both clients had visited the clinic on the same day denying other recent risk exposures. Inspection of the acupuncturist's practice revealed high-risk re-use and inappropriate storage of disposable needles. The Regional Health Authority ordered cessation of clinic practice until infection control measures were remediated. A public service announcement and mailed notifications to clients identified from practitioner records recommended that all clients be tested for HBV, human immunodeficiency virus (HIV) and hepatitis C. CONCLUSIONS: A clear epidemiological linkage of these two acute HBV infections to the same acupuncture clinic, evidence of substandard infection control practice in the clinic and identical HBV molecular and genotypic profiles of the two cases are highly suggestive that contaminated acupuncture needles likely resulted in at least two cases of acute HBV infection. This is the first known reported transmission of HBV from acupuncturists re-use of disposable needles and the first HBV outbreak associated with exposure to acupuncture reported this century in an industrialized country. Increased provider oversight and patient education may prevent future outbreaks.

Public health response to outbreaks of Avian Influenza A(H5N2) and (H5N1) among poultry - British Columbia, December 2014-February 2015.

In December 2014, the first detection in Canada of a highly pathogenic avian influenza A (HPAI) virus was reported in poultry within the Fraser Health Authority of British Columbia. It was the second outbreak of HPAI from Eurasian H5 reassortment viruses in North America. The Fraser Health Authority provided the lead public health coordination for this response as well as consultation and support to the occupational health response. The public health response focused on contact tracing, monitoring and follow-up for household, farm worker and other community contacts exposed on the affected farms. A total of 50 contacts were identified. Contacts received daily active monitoring by public health nurses for seven days from their last exposure and were advised to self-monitor until day 10. All contacts and other household members were recommended seasonal influenza vaccination to protect against further possible reassortment with human influenza viruses circulating within the community at the time. A total of 26 (52%) contacts were recommended chemoprophylaxis for ongoing exposure to the affected barns and flocks, of whom only 11 (42%) initiated this. During the seven-day active surveillance period, four contacts developed acute respiratory symptoms and influenza B was identified in one individual. Local area health care providers and acute care facilities were alerted to the outbreak and public messaging was provided regarding the human health risks from avian influenza. Collaboration between health and agriculture at the local, regional, provincial and federal levels was key to a rapid response to this outbreak.

Case of vaccine-associated measles five weeks post-immunisation, British Columbia, Canada, October 2013.

We describe a case of vaccine-associated measles in a two-year-old patient from British Columbia, Canada, in October 2013, who received her first dose of measles-containing vaccine 37 days prior to onset of prodromal symptoms. Identification of this delayed vaccine-associated case occurred in the context of an outbreak investigation of a measles cluster.

The comparative effectiveness of adjuvanted and unadjuvanted trivalent inactivated influenza vaccine (TIV) in the elderly.

BACKGROUND: Influenza is associated with a high mortality and morbidity in older adults. Vaccination remains the most effective method of preventing influenza and its consequences, however, vaccine effectiveness decreases with increasing age and increasing immunosenescence. In older adults, immunogenicity studies suggest an MF59 adjuvanted influenza vaccine (ATIV, Fluad(®)) may help. METHODS: We evaluated the comparative effectiveness of ATIV, and unadjuvanted trivalent influenza vaccine (TIV) in reducing laboratory confirmed influenza in the elderly. Elderly in three health authorities during winter 2011-12 were included in a community based case control study design. Cases tested positive and controls tested negative for influenza. Subjects with known immunosuppression were excluded. Logistic regression was used to calculate the odds ratio of vaccination (vs. no vaccination) in cases and controls. ATIV and TIV effectiveness was described. RESULTS: A total of 282 eligible participants were enrolled (84 cases). Almost half (136) were in a long term care facility and were 85 years of age or older (132) vaccine effectiveness decreased with increasing age. In a variety of multivariate analyses, ATIV was significantly protective at around 60% (p=0.02), with only residence in long term care and health authority also significant. Vaccine effectiveness increased in non-long term care residents. In multivariate analyses TIV was ineffective. CONCLUSION: An MF59 adjuvanted vaccine provided significantly improved protection against influenza in the elderly.

Uptake and behavioural and attitudinal determinants of immunization in an expanded routine infant hepatitis B vaccination program in British Columbia.

INTRODUCTION: British Columbia (BC) implemented a universal infant hepatitis B (HB) immunization program in 2001. The study objective was to evaluate HB immunization coverage among the first six-month cohort of eligible infants in the province outside of the Vancouver-Richmond health region and to assess parent/guardian behavioural and attitudinal determinants of HB immunization. METHODS: A cross-sectional survey of HB immunization was conducted using a random sample of eligible infants born between 1 January-30 June 2001. HB immunization coverage data were obtained from the provincial Public Health Information System, and through a telephone survey of 487 of eligible infants' parents/guardians that was conducted between October 2002-January 2003. At this time, parents/guardians were also asked about behaviours and attitudes towards immunization, based on the Immunization Health Belief Model Scale. RESULTS: HB immunization coverage with at least one dose of HB vaccine was 89% and uptake of 3 doses of HB vaccine was 78%. HB immunization was significantly associated (p<0.001) with a recommendation for HB immunization from a health care professional. The main reason for non-HB immunization was parental concern about side effects. DISCUSSION: Seventy-eight percent of infants completed the 3-dose HB vaccination schedule. Parental behaviour regarding HB immunization of their children was strongly influenced by a supportive recommendation from either a nurse or doctor.

Comparing benefits and risks of immunization.

BACKGROUND: This paper uses a straightforward method of quantifying the benefits and risks of immunization, illustrated by universal immunization programs in British Columbia against invasive Haemophilus influenzae type b disease (Hib), measles, rubella, and paralytic poliomyelitis. METHODS: Data were extracted from provincial communicable disease and vaccine adverse event surveillance systems. Average disease incidence was compared before and after implementing universal immunization programs. Estimates of prevented deaths and serious disease complications were calculated and compared with expected numbers of serious vaccine-associated adverse events (VAAEs). RESULTS: Average incidence of reported cases decreased 90 to 100% over a 5-year period after implementing universal programs. These benefits were sustained or strengthened over time. Rates of reported serious VAAEs were low. DISCUSSION: The remarkable success of immunization has created a paradox. Despite a low absolute risk of serious VAAEs, the relative risk of some VAAEs can exceed risk of disease in the province.

The relationship between hirudin and activated clotting time: implications for patients with heparin-induced thrombocytopenia undergoing cardiac surgery.

UNLABELLED: Anticoagulation with recombinant hirudin (r-hirudin) (Refludan) has been suggested as an alternative to heparin for patients with heparin-induced thrombocytopenia requiring cardiac surgery. We sought to develop a modified activated coagulation time (ACT) that would allow quantification of the levels of r-hirudin required during cardiopulmonary bypass (CPB). Twenty-one patients scheduled for elective cardiac surgical procedures requiring CPB were enrolled in this IRB-approved study. R-hirudin was added to blood specimens obtained before heparin administration (before CPB) and 30 min after heparin neutralization with protamine (after CPB) to result in concentrations of 0, 2, 4, 6, 7, or 8 microg/mL. Kaolin/ACT and complete blood count measurements were assayed in native specimens (first 10 patients, Phase I) or in specimens mixed with equal volumes of commercial normal plasma (second 11 patients, Phase II). In Phase I, good (r(2) = 0.83) linear relationships between ACT values and r-hirudin concentrations (< or =4 microg/mL) were observed in specimens obtained before CPB. However, ACT values were markedly prolonged (P < 0.0001) by r-hirudin in specimens obtained after CPB, with ACT values generally exceeding the ACT's detection limit (>999 s) at hirudin concentrations >2 microg/mL. In patient specimens mixed with normal plasma (Phase II), ACT/hirudin relationships (i.e., hirudin/ACT slope values obtained with hirudin concentration < or =4 microg/mL) in the post-CPB period (0.022 +/- 0.004 microg. mL(-1). s(-1)) were similar (P = 0.47) to those (0.019 +/- 0.004 microg. mL(-1). s(-1)) obtained in the pre-CPB period. Accordingly, a significant relationship between normal plasma-supplemented ACT values and predilution hirudin concentration was obtained in the post-CPB (hirudin = 0.039ACT - 4.34, r(2) = 0.91) period. Although our data demonstrate that the ACT test cannot be used to monitor hirudin during CPB, the addition of 50% normal plasma to post-CPB hemodiluted blood specimens yields a consistent linear relationship between hirudin concentration and ACT values up to a predilution concentration of 8 microg/mL. Plasma-modified ACT may be useful in monitoring hirudin anticoagulation during CPB. IMPLICATIONS: A modified activated clotting time test system that may be helpful in monitoring hirudin anticoagulation in patients with heparin-induced thrombocytopenia during cardiac surgery with cardiopulmonary bypass is described.

Public health and hepatitis C.

This paper reviews key public health aspects related to surveillance, transmission and primary prevention of hepatitis C. Hepatitis C is now a reportable disease in all Canadian provinces and territories. Although prevalence in Canada is estimated at under 1%, that associated with injection drug use (IDU) approaches 90%. The epidemiology of new HCV infections in Canada is now primarily defined by IDU behaviour, with annual incidence rates among new drug injectors exceeding 25%. HCV is less efficiently transmitted through other routes of exposure. An effective vaccine against HCV remains elusive. Some jurisdictions offer hepatitis A and hepatitis B vaccine to HCV-infected persons. An array of harm reduction strategies targeting IDU has been implemented but underdeployed across Canada, and has been ineffective to date in controlling the HCV epidemic. Public policy alternatives, such as legalization and regulation of injection drugs, are being debated. Improved HCV preventive strategies are urgently required and need careful evaluation.

The effect of epsilon-aminocaproic acid on HemoSTATUS and kaolin-activated clotting time measurements.

UNLABELLED: New point-of-care assays have been used to identify patients with heparin resistance (i.e. heparin dose response test; Medtronic Blood Management, Parker, CO) and who have platelet dysfunction (i.e. HemoSTATUS; Medtronic Blood Management). We examined the effect of epsilon-aminocaproic acid on results from these two point-of-care tests in patients undergoing cardiac surgery. Twenty patients scheduled for elective cardiac surgical procedures were enrolled in this prospective study. HemoSTATUS clot ratio (% maximal) values in Channels (Ch) 3-6 (Ch 3: 26 +/- 25, Ch 4: 66 +/- 23, Ch 5: 84 +/- 20, Ch 6: 106 +/- 18) obtained after the IV administration of epsilon-aminocaproic acid were similar to values obtained before the administration of this agent (Ch 3: 26 +/- 20, Ch 4: 69 +/- 23, Ch 5: 86 +/- 19, Ch 6: 109 +/- 14). Slope values (86 +/- 23 s x U(-1) x mL(-1)) and projected heparin concentrations (4 +/- 1 U/mL) obtained before the administration of epsilon-aminocaproic acid were similar to slope values (88 +/- 21 s x U(-1) x mL(-1)) and projected heparin concentrations (4 +/- 1 U/mL) values obtained after administration of this agent. Our data indicate that HemoSTATUS clot ratio values and heparin dose response values are not significantly affected after IV dosing of epsilon-aminocaproic acid. IMPLICATIONS: Values from two activated coagulation time-based test systems used to identify significant heparin resistance or platelet dysfunction after cardiopulmonary bypass were not significantly affected by epsilon-aminocaproic acid administered IV.

Clinical evaluation of a new, point-of-care hemocytometer.

OBJECTIVE: This study was designed to compare results obtained with a new point-of-care hemocytometer with those of two established (point-of-care and laboratory-based) instruments. DESIGN: To compare CBC values between established laboratory-based and point-of-care instruments, measurements were performed on routinely obtained blood specimens for CBC analysis in our institutional laboratory (phase I) and on specimens from cardiac surgical patients before initiation of cardiopulmonary bypass and after discontinuation of cardiopulmonary bypass in phase II. SETTING: Surgical and hospitalized patients at a tertiary care center. PATIENTS: Measurements were obtained by using blood specimens obtained from 141 hospitalized patients from different services (phase I) or from a consecutive series of 204 patients undergoing cardiac operations (phase II). MEASUREMENTS AND MAIN RESULTS: Hemoglobin (HGB), platelet count (PLT), red blood cell count, and white blood cell count (WBC) were measured with two on-site and one laboratory-based instruments. Hematocrit (HCT) was calculated by using measured variables. Linear regression demonstrated good correlations between Ichor and T540 HGB (r2 = .95), HCT (r2 = .95), PLT (r2 = .94), and WBC (r2 = .95) results (n = 408); similarly, good correlations were observed with Coulter STKS HGB (r2 = .92), HCT (r2 = .91), and PLT (r2 = .94) results (n = 141). The relationship between Ichor and Coulter STKS WBC (r2 = .27) was poor; however, when two Ichor-derived outlier values (>50) were excluded, the relationship was very good (r2 = .99). Bias analysis (mean +/- SD) demonstrated similar results between Ichor and T540 HGB (0.003+/-0.5), HCT (-0.21+/-1.5), WBC (0.79+/-1.3), and PLT values (-9.2+/-16.6) as well as STKS HGB (-0.08+/-0.7), HCT (-0.69+/-2.3), WBC (-0.62+/-5.8), and PLT values (-10.2+/-21.4). CONCLUSIONS: The Ichor hemocytometer provides accurate hematologic results that can facilitate rapid quantitative assessment of CBC variables and thus may be clinically useful, especially in critically ill patients.

An outbreak of mumps among young adults in Vancouver, British Columbia, associated with 'rave' parties.

UNLABELLED: In early 1997 an unexpectedly high number of cases of mumps was reported in Vancouver, British Columbia. METHODS: A case control study was conducted to address four objectives: 1) Describe the outbreak and the population at risk, 2) examine the impact of mumps on this population, 3) identify personal risk factors for infection, and 4) test the hypothesis that social gatherings, 'rave' parties in particular, were a risk factor in this outbreak. RESULTS: Mumps infection was associated with: attending a rave party [OR = 17; 95% CI: 2.7-710], residing in Vancouver [OR = 3.7; 95% CI: 1.4-10], and contact with a person with mumps [OR = 13; 95% CI: 2-552], during the 'exposure' period. Vaccine effectiveness, ascertained by self-reported immunization status, was 80% [95% CI: 29%-96%]. CONCLUSIONS: Attendance at rave parties was associated with mumps infection during this outbreak. Many persons aged 17-40 may remain susceptible to mumps; in BC these persons are eligible for one dose of MMR and should be encouraged to be vaccinated.