We present the final number of new HIV diagnoses in BC for 2013 and describe recent trends by gender, region and exposure category.
We used provincial HIV surveillance data to describe the number of new HIV diagnoses in BC and historical trends for 2003-2013. New HIV diagnoses are a proxy for incidence because individuals may receive a diagnosis at varying stages of HIV infection.
The final number of new HIV diagnoses in 2013 is 272, for a rate of 5.8 per 100,000 (Figure 1). This is a 15% increase from 237 cases in 2012 (5.1 per 100,000), which was a record low. The annual count, however, remains lower than in years prior to 2012 and is consistent with an overall decreasing trend.
Figure 1. New HIV diagnoses in BC and Canada by historical trend, 1995-2013
The rate of HIV diagnoses is stable or increasing in all health authorities in 2013 (Figure 2): VCH (12.1 per 100,000; 143 cases), VIHA (3.8 per 100,000; 29 cases) and IHA (1.7 per 100,000; 13 cases) showed similar rates compared to 2012. The rate of new diagnoses increased in FHA to 68 cases (4.1 per 100,000) and in NHA to 17 cases (5.8 per 100,000).
Figure 2. New HIV diagnoses in BC by health authority, 2003-2013
New HIV diagnoses increased slightly among females to 33 cases (1.4 per 100,000) from 29 cases (1.2 per 100,000) in 2012. Males showed a more pronounced increase in 2013 to 239 cases (10.3 per 100,000) from 208 cases (9.1 per 100,000).
For exposure category (Figure 3), there were 150 (55%) new diagnoses among gay, bisexual and other men who have sex with men (MSM), similar to 2012 (149 cases). There was no change in new HIV diagnoses among injection drug users (IDU): 29 (11%) new diagnoses in 2013, which was the same as in 2012. However, there were 60 (22%) new diagnoses among heterosexual contacts, which was an increase from 2012 (52 cases).
Figure 3. Persons testing newly positive for HIV in BC by risk exposure, 2003-2013
An investigation into possible reasons for the increase in new HIV diagnoses for 2013 suggested that increased testing as a result of the STOP HIV/AIDS program likely contributed to the higher case count (for example, a greater number of cases diagnosed in hospitals in 2013 compared to earlier years).
While the number of new HIV diagnoses increased in 2013 compared to 2012, the rate remains lower than all previous years. This increase may reflect normal year-to-year variation as part of an overall decreasing trend in BC. Furthermore, the increase in new diagnoses may be related to increased testing within the context of the STOP HIV/AIDS program that was rolled out in the province. However, we cannot rule out an increase in HIV incidence in some subgroups of the population and will need to consider co-infection with other STIs that may be contributing to the higher number of HIV diagnoses.
Teddy Consolacion and Mark Gilbert, Clinical Prevention Services, BCCDC