Could urine be useful for the diagnosis of Chlamydia trachomatis pneumonia in infancy?

A 9-week-old infant presented with respiratory distress. The presumptive diagnosis of Chlamydia trachomatis pneumonia was ultimately made in a novel manner by a positive nucleic acid amplification test on a urine sample.

Epidemiology of Haemophilus influenzae serotype a, North American Arctic, 2000-2005.

Before the introduction of Haemophilus influenzae type b (Hib) conjugate vaccines, rates of invasive H. influenzae disease among indigenous people of the North American Arctic were among the highest in the world. Routine vaccination reduced rates to low levels; however, serotype replacement with non-type b strains may result in a reemergence of invasive disease in children. We reviewed population-based data on invasive H. influenzae in Alaska and northern Canada from 2000-2005; 138 cases were reported. Among 88 typeable isolates, 42 (48%) were H. influenzae type a (Hia); 35 (83%) occurred in indigenous peoples. Among Hia patients, median age was 1.1 years; 62% were male; 1 adult died. Common clinical manifestations included meningitis, pneumonia, and septic arthritis. Overall annual incidence was 0.9 cases per 100,000 population. Incidence among indigenous children <2 years of age in Alaska and northern Canada was 21 and 102, respectively. Serotype a is now the most common H. influenzae serotype in the North American Arctic; the highest rates are among indigenous children.

Viral hepatitis in the Arctic. A review from a Circumpolar Workshop on Viral hepatitis, ICCH13.

This article is a review of the viral hepatitis workshop, held during the 13th International Congress of the Circumpolar Health consists of a review of data on viral hepatitis in the Arctic territories of four countries: Canada, Greenland, Russia and United States (Alaska). The main purpose of the workshop was to exchange knowledge on viral hepatitis in the Arctic and identify further needs for collaborative hepatitis research, which is planned to be implemented through the established Viral Hepatitis Working Group in the Arctic. The review is based on the available published research results, surveillance data and professional opinions of the authors. The information is presented by Arctic country. Viral hepatitis constitutes an important problem among Aboriginal peoples of the Arctic; the incidence of most types of viral hepatitis is higher among indigenous populations than in the general public. However, due to differences in the available information from each of the four Arctic countries, it is difficult to compare differences in types of disease in them. The main areas for future research are: HBV genotypes distribution, relations between different types of HBV, HCV and disease outcomes, HBV mutation rate and specific substitutions in the HBV genome over time in the Arctic, and occurrence of active liver disease in HBsAg carriers living in the Arctic, as well as further research in viral hepatitis A, C, D and E.

Enhanced surveillance for adverse events following immunization: Two years of dTap catch-up among high school students in Yukon, Canada (2004, 2005).

BACKGROUND: To address the increasing age of pertussis cases, Yukon replaced the Grade 9 tetanus/diphtheria/inactivated polio booster with diphtheria/tetanus/acellular pertussis (dTap) and implemented a dTap catch-up program for Grade 12 students. The program began in June 2004, making Yukon one of the first Canadian jurisdictions to introduce dTap within five years of a tetanus booster. We implemented enhanced surveillance to monitor adverse events following immunization (AEFI) to determine whether students receiving dTap > or =3 to <5 years after their last tetanus booster were at increased risk of severe AEFI. METHODS: Students completed a self-administered AEFI questionnaire one week post-dTap vaccination. Public health professionals contacted students reporting severe AEFI. Health care providers were requested to report AEFI. Symptom rate, severity and duration were compared between students receiving dTap > or =3 to <5 years after their last tetanus booster and those receiving it >5 years later. RESULTS: The > or =3 to <5 years group was more likely than the > or =5 years group to report pain at the injection site (70.6% vs. 61.5%, p=0.038) and less likely to report injection site redness (10.0% vs. 17.3%, p=0.022), injection site swelling (8.9% vs. 16.4%, p=0.013), decreased energy (10.0% vs. 17.1%, p=0.023), body aches (2.2% vs. 7.2%, p=0.014) and sore joints (3.3% vs. 10.1%, p=0.004). Severe AEFI did not differ between the groups (3.3% vs. 5.6%, p=0.232). Health care professionals reported no AEFI. CONCLUSIONS: Results suggest no increased risk of severe AEFI among students receiving dTap > or =3 to <5 years after their last tetanus booster.

Potential factors that may affect acceptance of routine prenatal HIV testing.

BACKGROUND: Despite increasing advocacy for an "opt-out" strategy in routine prenatal HIV screening programs in Canada, no published studies have examined factors that may affect acceptance of prenatal HIV testing. METHODS: We included all pregnant women in Alberta who received prenatal care (N = 38,712) and their caregivers (N = 2,007) between January 1 and November 30, 2000. Factors associated with non-acceptance of HIV testing in both pregnant women and their caregivers were assessed using multivariate logistic regression. RESULTS: Overall, 1.5% of women declined HIV testing. First Nations women were about twice as likely to decline the test (adjusted odds ratio [OR(adj)] 1.91, 95% CI [1.42-2.58]) compared to non-First Nations women (p < 0.001). The proportion also increased with age (chi2 trend p < 0.001) in the general population. In First Nations women, however, most (3.2%) declined in the 20-24 year age group. No significant effect was seen for a socio-economic status marker or for the place of residence. The caregivers of women who declined HIV testing were more likely to be female (OR(adj) 1.56 [1.28-1.89]), midwives (OR(adj) 140.65 [58.61-337.49]), other non-obstetrical medical specialties (OR(adj) 4.92 [1.94-12.47]), and general practitioners (OR(adj) 3.44 [1.87-6.33]). CONCLUSION: In an "opt-out" routine prenatal HIV screening program, the characteristics of both the pregnant women and their caregivers may contribute to the non-acceptance of HIV testing. A higher likelihood of declining HIV testing among First Nations pregnant women and other pregnant women under the care of midwives and female physicians warrants further study.

Immunoglobulin mimicry by Hepatitis C Virus envelope protein E2.

Hepatitis C virus (HCV) establishes persistent infection in the majority of infected individuals. The currently accepted hypothesis of immune evasion by antigenic variation in hypervariable region 1 (HVR1) of glycoprotein E2 does not however, explain the lack of subsequent immune recognition. Here, we show that the N-terminal region of E2 is antigenically and structurally similar to human immunoglobulin (Ig) variable domains. E2 is recognized by anti-human IgG antibodies and also possesses common amino acid (aa) sequence features of the conserved v-gene framework regions of human Ig light chains in particular but also heavy chains and T cell receptors. Using a position specific scoring system, the degree of similarity of HVR1 to Ig types correlated with immune escape and persistence in humans and experimentally infected chimpanzees. We propose a unique role for threshold levels of Ig molecular mimicry in HCV biology that not only advances our concept of viral immune escape and persistent infection but also provides insight into host-dependent disease patterns.

Labour force participation among individuals with hepatitis C in the US.

BACKGROUND: In 1996, the number of persons newly infected with hepatitis C virus (HCV) in the US was estimated to be 36 000. As a chronic disease that primarily affects younger persons, hepatitis C has the potential to influence employment considerably. OBJECTIVE: To estimate employment effects associated with hepatitis C morbidity. DESIGN: An economic model of labour supply, which used the outcome measure workforce participation (yes/no), was applied. STUDY PARTICIPANTS: The study samples (by gender) were comprised of persons 18-65 years of age, with and without serological evidence of HCV infection, and with normal or elevated levels of alanine aminotransferase (ALT) who participated in the National Health and Nutrition Examination Survey III from 1988-1994. RESULTS: After controlling for the potential confounding effects of demographic, social, and economic factors, positive HCV status/normal ALT level in males was associated with a 10.7% reduction in labour force participation (when compared with negative HCV status). Positive HCV status and elevated ALT levels was associated with a 17.5% reduction in employment. The results for females were not statistically significant. CONCLUSIONS: Nationally, the employment response for HCV-positive status and elevated ALT levels translates into an excess non-employment of 48 000 males annually.

Mandatory reporting of HIV infection and opt-out prenatal screening for HIV infection: effect on testing rates.

BACKGROUND: Mandatory reporting of HIV infection to public health authorities, although now common, may deter people from undergoing testing. We examined HIV testing frequency in Alberta before and after mandatory reporting was implemented. We also examined the effect on testing rates among pregnant women when Alberta adopted an opt-out approach to prenatal HIV screening. METHODS: Using data from the Provincial Laboratory for Public Health, we determined the number of HIV tests done between Jan. 1, 1993, and Dec. 31, 2000, for males and females in Alberta. We used data from the Canadian Blood Services laboratories to obtain the number of tests conducted as part of the opt-out prenatal HIV testing program. Reporting of HIV infection became mandatory on May 1, 1998, and opt-out prenatal HIV testing was introduced on Sept. 1, 1998. RESULTS: Among males, the average annual percent increase in the number of HIV tests was 4.0% for the period before mandatory testing, as compared with 4.3% for the period after mandatory reporting was implemented; the difference in yearly trend was significant (p < 0.001). Among females, the average annual percent increase in the number of HIV tests was 9.2% for the period before mandatory reporting. In the month immediately following the adoption of opt-out prenatal HIV testing, the rate increased by 28%. Between 1999 and 2000, the average annual percent increase in the number of HIV tests among females was 1.4%. INTERPRETATION: The introduction of mandatory reporting of HIV infection did not appear to have a deterrent effect on rates of HIV testing. The implementation of an opt-out prenatal HIV testing policy resulted in a dramatic increase in the number of females being tested for HIV infection.

Acute nosocomial HCV infection detected by NAT of a regular blood donor.

BACKGROUND: Routine HCV NAT of blood donors to detect persons in the preseroconversion phase of acute infection was introduced in Canada in October 1999. The source of virus exposure was investigated in the first, and to date only, blood donor found to be HCV NAT positive, anti-HCV negative in Canada. He was a regular donor with none of the commonly reported risk factors for HCV infection. STUDY DESIGN AND METHODS: Epidemiologic follow-up revealed that the blood donor had received antibiotics at an outpatient IV clinic 5 weeks before donation. IV solution bags and tubing for individual patients were stored in the clinic, and then the same equipment was used each time the patient returned for the next dose of antibiotics until it was replaced after every 72-hour period. Among eight other patients whose clinic visitation times overlapped was a man with chronic HCV infection. Genomic sequencing of HCV isolates from the blood donor, the patient with chronic hepatitis C, and local controls was carried out to study possible nosocomial infection. RESULTS: Genomic sequencing showed a high degree of relatedness in the hypervariable region of HCV isolates from the blood donor and putative source patient as compared with controls. Detailed molecular analysis of quasispecies of the HCV isolates further indicated that viruses from the two individuals were genetically very close to each other. CONCLUSION: The introduction of routine screening of blood donors by HCV NAT was directly responsible for the early detection and investigation of an unusual case of HCV infection involving a regular donor. Genomic sequencing studies provided firm evidence of patient-to-patient transmission of HCV in an IV clinic. The report clearly demonstrates the value of molecular fingerprinting in tracking nosocomial HCV infections.