Case series of rash associated with influenza B in school children.

This case series describes morbilliform and other rash presentations among schoolchildren during a March 2014 outbreak of influenza-like illness (ILI) in British Columbia, Canada. Multiplex nucleic acid testing of nasopharyngeal specimens and paired serologic investigations identified that influenza B, characterized as B/Massachusetts/02/2012-like (Yamagata-lineage), was the only viral aetiology and most likely cause of ILI and rash. An association between influenza B and rash has been described infrequently elsewhere, and not previously in North America. Influenza B should be considered in the differential diagnosis of febrile exanthem. Evaluation of the nature, incidence and contributing agent-host-environment interactions, and immunologic mechanisms to possibly explain influenza-associated rash is warranted.

Transmission dynamics and risk factors for pandemic H1N1-related illness: outbreak investigation in a rural community of British Columbia, Canada.

OBJECTIVE: To characterize the first-wave epidemiologic features of influenza-like illness (ILI) associated with the novel pandemic A/H1N1 [A(H1N1)pdm09] virus. METHODS: We used generalized linear mixed models (GLMM) to assess risk factors and non-parametric and/or parametric distributions to estimate attack rates, secondary attack rates (SAR), duration of illness, and serial interval during a laboratory-confirmed community outbreak of A(H1N1)pdm09 clustered around on-reserve residents and households of an elementary school in rural British Columbia, Canada, in late April/early May 2009. ILI details were collected as part of outbreak investigation by community telephone survey in early June 2009. RESULTS: Overall, 92/408 (23%) of participants developed ILI and 36/408 (9%) experienced medically attended ILI (MAILI). The overall SAR in households was 22%: highest among participants 1-4 years of age (yoa) (50%) followed by < 1 yoa (38%), 5-8 yoa (20%), 10-19 yoa (13%), 20-49 yoa (20%), and 50-64 yoa (0%). The median serial interval was estimated at 3·5 days (95% CI: 2·1-5·1). In multivariable GLMM analysis, having a chronic condition (OR: 2·58; 95% CI: 1·1-6·04), younger age [1-8 yoa: OR: 4·63; 95% CI: 2·25-9·52; 9-19 yoa: OR: 1·95; 95% CI: 0·97-3·9 (referent: ≥ 20 yoa)] and receipt of 2008-2009 influenza vaccine (OR: 2·68; 95% CI: 1·37-5·25) were associated with increased risk of ILI. Median duration of illness was 9 days, longer among those with chronic conditions (21 days). Median time to seeking care after developing illness was 4·5 days. On-reserve participants had higher chronic conditions, household density, ILI, MAILI, and SAR. CONCLUSIONS: During a community outbreak of A(H1N1)pdm09-related illness, we identified substantial clinical ILI attack rates exceeding 20% with secondary household attack rates as high as 50% in young children. The serial interval was short suggesting a narrow period to prevent transmission.

Seasonal influenza vaccine and increased risk of pandemic A/H1N1­related illness: first detection of the association in British Columbia, Canada.

BACKGROUND: In April 2009, an elementary school outbreak of pandemic H1N1 (pH1N1) influenza was reported in a community in northern British Columbia, Canada--an area that includes both non-Aboriginal and Aboriginal residents living on or off a reserve. During the outbreak investigation, we explored the relationship between prior receipt of trivalent inactivated influenza vaccine (TIV) and pH1N1-related illness. METHODS: A telephone survey was conducted from 15 May through 5 June 2009 among households of children attending any school in the affected community. Members of participating households where influenza-like illness (ILI) was described were then invited to submit blood samples for confirmation of pH1N1 infection by hemagglutination inhibition and microneutralization assays. Circulation of pH1N1 was concentrated among households of the elementary school and elsewhere-reserve to which analyses of TIV effect were thus restricted. Odds ratios (ORs) for the TIV effect on ILI were computed through logistic regression, with adjustment for age, comorbidity, household density, and Aboriginal status. The influence of within-household clustering was assessed through generalized-linear-mixed models. RESULTS: Of 408 participants, 92 (23%) met ILI criteria: 29 (32%) of 92 persons with ILI, compared with 61 (19%) 316 persons without ILI, had received the 2008-2009 formulation of TIV. Fully adjusted ORs for 2008-2009 TIV effect on ILI were 2.45 (95% confidence interval, 1.34-4.48) by logistic regression and 2.68 [95% confidence interval, 1.37-5.25) by generalized-linear-mixed model. CONCLUSIONS: An outbreak investigation in British Columbia during the late spring of 2009 provided the first indication of an unexpected association between receipt of TIV and pH1N1 illness. This led to 5 additional studies through the summer 2009 in Canada, each of which corroborated these initial findings.

Seroprevalence of West Nile virus in Saskatchewan's Five Hills Health Region, 2003.

BACKGROUND: The Five Hills Health Region of Saskatchewan reported the highest West Nile virus (WNV) case rates in the 2003 outbreak. A serologic and telephone survey was undertaken to assess the seroprevalence of the virus and the knowledge, attitudes and behaviours of the residents. METHODS: Respondents had to be at least 18 years of age, and residents of the Five Hills Health Region between July 1st and September 15th, 2003. Blood samples of respondents were tested at the National Microbiology Laboratory for flavivirus immunoglobulin using a WNV IgG ELISA and plaque reduction neutralization test. Descriptive analyses performed related to respondents' demographics, knowledge, attitudes, behaviours, and seropositivity. WNV infection risk was assessed using odds ratio. RESULTS: There were 619 questionnaire respondents, of whom 501 donated a blood sample. The seroprevalence of WNV in the Five Hills Health Region was 9.98% (95% CI 7.37-12.59%). Seropositivity of rural areas was 16.8% and urban was 3.2%. Most (97%) of participants thought WNV was an important health issue. Forty-eight percent of the participants used insect repellents containing DEET most of the time. There was good knowledge regarding WNV transmission and prevention of the spread of WNV. Rural compared to urban residents were six times more likely to be positive for WNV (OR=6.13, 95% CI 2.82-13.34). INTERPRETATION: This is the highest seroprevalence rate of West Nile virus recorded in North America thus far. Many factors could have influenced this outbreak, such as eco-region, early prolonged hot weather, level of mosquito control programs, urban and rural community differences, and personal protective behaviours.

A model for non-communicable disease surveillance in Canada: the prairie pilot diabetes surveillance system.

The Prairie Pilot Diabetes Surveillance Project was organized to design and test a prototype population-based surveillance system, using administrative data, for a chronic disease exemplar - diabetes mellitus. The Canadian model of a public health surveillance system for chronic conditions described here specifies a process by which administrative and claims data arising from provincial health insurance programs are merged into an annual person-level summary file (APLSF), yielding one summary record for each person insured within each province. The APLSF is the basis for a variety of estimates, including incidence, prevalence, mortality, complication rates and health services utilization. The model was used to produce comparable interprovincial estimates of several parameters with respect to diabetes for the entire population in the provinces of Alberta, Manitoba and Saskatchewan. All processing of identifiable health data occurred within the provinces where the data were generated. Combining results across provinces was based on further aggregation of the summary data from each province and not by pooling of identifiable person-level data. On the basis of preliminary outputs for diabetes mellitus, the model appears to provide coherent estimates of key diabetes parameters and reflects anticipated differences in health services and outcomes, by disease state. Three characteristics of the model recommend it as a resource for non-communicable disease surveillance in Canada: a) it maximizes the utility of existing data; b) it includes both those with and those without the disease in question; and c) it respects provincial legislation regarding personal health data, yet permits reporting of multi-provincial, population-based data.