In this update, we present the final number of new HIV diagnoses in BC for 2012, and describe recent trends by gender, region, and exposure category.
Methods
We used provincial HIV surveillance data to describe the number of new HIV diagnoses in BC overall (1986-2012) and to describe trends for the past ten years (2003-2012) by gender, regional health authority, and exposure category. Although new HIV diagnoses are a core component of HIV surveillance in BC, new HIV diagnoses are a proxy for HIV incidence because individuals may receive a diagnosis at varying stages of HIV infection.
Findings
In 2012, the lowest number of new HIV diagnoses per year on record was noted, continuing a declining trend over the past eight years. Overall, the final number of new HIV diagnoses for 2012 was 238, for a rate of 5.2 per 100,000 (Figure 1).
FIGURE 1: New HIV diagnoses in BC and Canada by historical trend, 1986 to 2012.
Breakdowns of rates of new HIV diagnoses by gender show a decline among both men and women, although rates for men continue to be higher compared to women. Across Health Authorities, rates of new HIV diagnoses are declining or stable. The highest rate was in Vancouver Coastal (12.2 per 100,000; 142 cases), followed by Fraser (2.7 per 100,000; 45 cases), Vancouver Island (3.4 per 100,000; 26 cases), Interior (1.6 cases per 100,000; 12 cases) and Northern (4.1 per 100,000; 12 cases).
By exposure category (Figure 2), gay, bisexual, and other men who have sex with men (MSM) represent 63% of new HIV positive cases in BC. Although the number of new HIV diagnoses (149 cases) for MSM was lower than in 2011 (167 cases), it is near the range of values over the previous nine years (range: 153-188 cases). Heterosexual contact accounted for 22% of cases in BC. The number of new HIV diagnoses (52 cases) from heterosexual contact moderately decreased in 2012 compared to 2011 (75 cases). The number of new HIV diagnoses for the heterosexual contact exposure category was below the range of values over the past nine years (range: 73-105 cases). People who use injection drugs (IDU) were 12% of the new HIV cases. The number of new HIV diagnoses among IDU declined from 34 cases in 2011 to 29 cases in 2012, continuing a decreasing trend first observed in 2008.
FIGURE 2: Persons Testing Newly Positive for HIV in BC by exposure category
Implications
The decrease in new HIV diagnoses overall in BC is encouraging and suggests that overall HIV incidence in the province is decreasing. While the decline in new HIV diagnoses is observed by gender and in many health authorities, the decrease in diagnoses is most apparent among people who use injection drugs (since 2008), and in 2012, among people who acquire HIV through heterosexual contact. In contrast, the number of new HIV diagnoses among MSM is not declining to the same extent, and as MSM comprise the majority of new HIV diagnoses in BC, expanding prevention efforts for this group is needed.
Notes
- MSM = men who have sex with men
- IDU = people who use injection drugs
- HET = people who report heterosexual contact
- Other = other reported exposure category
- NIR/UNK = no identified risk or exposure is unknown.
For further Information
See the 2011 BCCDC Annual HIV Surveillance report for more detailed surveillance data on new HIV diagnoses in 2011.
Acknowledgements
Travis Salway Hottes, Mark Gilbert, Clinical Prevention Services, BCCDC