# Sexually Transmitted and Blood-Borne Infections (STBBI) Surveillance Report

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Government of Yukon, Population and Public Health, Evidence and Evaluation
Data current up to December 31, 2023

# Epidemiological summary

Sexually transmitted and blood-borne infections (STBBIs) are infections that are transmitted from one person to another through close intimate contact or through blood-to-blood contact. While many STBBIs are curable or manageable with treatment, they remain a significant public health concern in Canada.

A total of 1,545 STBBI cases were reported among Yukon residents between 2019 and 2023. Chlamydia, syphilis (infectious and non-infectious), and gonorrhea were the most commonly reported STBBIs in the territory during this period. A dramatic increase in the rate of infectious syphilis was observed in the Yukon in 2022 and 2023 (see “Spotlight on Syphilis and Gonorrhea”). Rates of hepatitis B and C have remained fairly stable in the territory over the last five years. Caution should be taken when interpreting these annual incidence rates as the relatively low number of cases can result in fluctuations from year to year.

Starting in 2020, a decrease in the rates of some STBBIs is observed, with chlamydia showing the largest decline. This is likely due to the impacts of the COVID-19 pandemic, including disruptions in STBBI prevention, screening and testing, and treatment services; shifts in sexual behaviour with lockdowns and restrictions on social gatherings; and disparities in access to care among vulnerable populations.1 The number of cases diagnosed from 2020-2022 may be lower than the true number of infections during these years and reported rates should be interpreted with caution.

# Overview (all infections)

#### Counts of reported STBBI cases*, Yukon, 2019-2023

Disease | Count
--- | ---
2019 | 2020 | 2021 | 2022 | 2023
Chlamydia | 314 | 264 | 213 | 207 | 237
Gonorrhea | 16 | 19 | 7 | 8 | 20
Hepatitis B | 5 | 2 | 6 | 6 | 5
Hepatitis C | 14 | 12 | 8 | 10 | 8
Infectious Syphilis | 2 | 3 | 7 | 61 | 59
Non-Infectious Syphilis | 1 | 0 | 5 | 7 | 19
*Counts include genital and extra-genital cases of chlamydia and gonorrhea, and chronic, active and unspecified cases of hepatitis B and C.

#### Rates of reported STBBI cases per 100,000 population, Yukon, 2019-2023

# Spotlight on syphilis and gonorrhea

Syphilis and gonorrhea are bacterial illnesses that are primarily transmitted through sexual contact, including genital, anal, or oral sex. Congenital syphilis is a type of syphilis that is passed from a pregnant person to a fetus during pregnancy and if untreated, can cause miscarriage, pre-term birth, still birth, or other serious problems after delivery.

Those with gonorrhea infection are often asymptomatic, which is why screening and contact tracing are so important for diagnosis and preventing further spread. If left untreated, gonorrhea infection can have serious health impacts, including pelvic inflammatory disease in women, chronic pain, and infertility in males and females.

Early symptoms of syphilis can include, but are not limited to, a painless sore in the genital or anus area or mouth, fever, rash, and swollen glands. Syphilis and gonorrhea are treatable with antibiotics; however, it is possible to become re-infected after treatment.

Untreated syphilis infections can progress through four stages: primary, secondary, latent (early and late) and tertiary. Primary, secondary and early latent stages are considered infectious, meaning it can be transmitted from person to person during these stages. Without treatment, syphilis will progress to latent stages where no symptoms are present, but the infection remains in the body. These infections with a late latent stage are represented in the non-infectious syphilis cases in the data presented. Latent syphilis can progress to tertiary syphilis where the infection can affect several organs, including the brain.

Gonorrhea and syphilis follow chlamydia as the leading sexually transmitted infections (STIs) in Canada. Rates of both gonorrhea and syphilis have been steadily rising in Canada. The national rate of reported gonorrhea cases in 2021 was two times higher than the rate in 2012 (84.2 and 37.5 cases per 100,000 population, respectively).3 The Canadian infectious syphilis rate increased by 109% between 2018 and 2022 (17.3 and 36.1 cases per 100,000 population, respectively).2

Consistent with national trends, rates of infectious syphilis have increased at an alarming rate in the Yukon. The incidence rate for infectious syphilis in 2022 was 138.7 cases per 100,000 population, which is 3.8 times higher than the national rate (36.6 cases per 100,000 population) and nearly 30 times higher than Yukon’s rate in 2019 (4.8 cases per 100,000 population). Rates remained elevated in 2023 with 130.6 cases per 100,000 population. Between 2019 and 2023, Yukon’s infectious syphilis rates were highest among 20 to 39-year-olds (n=86; 662.6 cases per 100,000 population). Males consistently accounted for the majority of cases over the last five years; however, the proportion of female infectious syphilis cases increased in 2023. Rates were higher among residents of rural communities throughout the territory compared to Whitehorse residents.

Similar to the recent surge in syphilis infections, preliminary data from the first six months of 2024 suggest that gonorrhea rates are now rapidly rising in the Yukon. As of June 30, 2024, there were 67 confirmed gonorrhea cases reported across the territory, which compares to 20 cases in 2023. The reported gonorrhea cases in the first half of 2024 almost equals the total number of cases from the last five years in the territory (n=70). The increase in cases is not fully explained by an increase in laboratory testing given that gonorrhea testing volumes only increased by 7% in the first six months of 2024 when compared to the same period in 2023. Among the 2024 gonorrhea infections, rates were highest among individuals aged 20-39 years (n=44; 320.9 cases per 100,000 population) and affected females and males equally (53% females). The share of female gonorrhea cases grew in 2024 in comparison to the 33% of female cases reported between 2019 and 2023. Rates were fairly equal among Whitehorse residents and residents of rural communities throughout the territory.

Antimicrobial-resistant gonorrhea (AMR-GC) is a significant and growing issue worldwide. More than 80% of gonorrhea cases were diagnosed by nucleic acid amplification tests (NAATs) in Canada in 2019, for which there is no antimicrobial susceptibility data.4 This has resulted in surveillance knowledge gaps in the detection and monitoring of AMR-GC. Given the rise of AMR-GC, it’s crucial for individuals to consult their healthcare provider about the most suitable tests. Providers are encouraged to collect cultures prior to collecting the NAAT specimen and prior to treatment for all symptomatic clients.

The rising rates of STBBIs in the Yukon and across Canada highlight the need to increase prevention, and ensure adequate access to testing and effective treatment to address this public health challenge.

For more information on sexually transmitted infections, including prevention and how to get tested, visit the Better to Know website.

Healthcare providers can refer to the Yukon Treatment Guidelines for Sexually Transmitted Infections (STI) in Adolescents and Adults 2020 for more information on testing, treatment, and Test of Cure guidelines.

Additional STBBI data can be found in Yukon’s 2022 Health Status Report.

# STBBI trends by age and sex

### Chlamydia

There were 1,235 cases of chlamydia (genital and extra-genital) reported among Yukon residents, which represented 80% of all reported STBBIs in the territory between 2019 and 2023. Females consistently accounted for the majority of all chlamydia cases over the last five years. The highest proportion of cases were in the 20-39 year age group.

#### Proportion of chlamydia cases by sex, 2019-2023 (N=1235)

#### Number of chlamydia cases by age group, 2019-2023 (N=1235)

### Gonorrhea

There were 70 cases of gonorrhea (genital and extra-genital) reported among Yukon residents between 2019 and 2023. Two-thirds of cases were reported among males during this period, and gonorrhea infections were most commonly reported in the 20-39 age group.

#### Proportion of gonorrhea cases by sex, 2019-2023 (N=70)

#### Number of gonorrhea cases by age group, 2019-2023 (N=70)

### Hepatitis B

There were 24 cases of acute, chronic, and unspecified hepatitis B reported among Yukon residents between 2019 and 2023. Fluctuations from year to year were observed due to the small annual counts, but overall, hepatitis B cases were most commonly reported among females and among those 20-39 years of age.

#### Proportion of hepatitis B cases by sex, 2019-2023 (N=24)

#### Number of hepatitis B cases by age group, 2019-2023 (N=24)

### Hepatitis C

There were 52 cases of acute, chronic, and unspecified hepatitis C reported among Yukon residents between 2019 and 2023. There were fluctuations from year to year, but overall, the majority of cases were male and between the ages of 20 to 39 years.

#### Proportion of hepatitis C cases by sex, 2019-2023 (N=52)

#### Number of hepatits C cases by age group, 2019-2023 (N=52)

### Infectious syphilis

There were 132 cases of infectious syphilis reported among Yukon residents between 2019 and 2023, 90% of which were reported in the last two years. Males consistently accounted for the majority of all cases over the last five years; however, the proportion of female infectious syphilis cases increased in 2023. The highest proportion of cases were in the 20-39 year age group.

#### Proportion of infectious syphilis cases by sex, 2019-2023 (N=132)

#### Number of infectious syphilis cases by age group, 2019-2023 (N=132)

### Non-infectious syphilis

There were 32 cases of non-infectious syphilis reported among Yukon residents between 2019 and 2023. More than half (60%) of these infections were reported in 2023. Overall, non-infectious syphilis affected females and males equally over the last five years. From 2019 to 2022, infections were predominantly reported among males. However, in 2023, the percentage of infections reported among females increased. The highest proportion of cases were in the 20-39 year age group.

#### Proportion of non-infectious syphilis cases by sex, 2019-2023 (N=32)

#### Number of non-infectious syphilis cases by age group, 2019-2023 (N=32)

# Technical notes

The data for this report were based on information extracted from Panorama (Yukon’s immunization and reportable disease electronic registry) as of July 24, 2024, for Yukon resident cases reported between 2019 and 2023. The data provided represent a snapshot of diagnosed cases at the time of reporting and the numbers are subject to change. Fluctuations can occur as cases are investigated and updated.

Only cases meeting the confirmed case classification are included in the report counts. Please see the Public Health Agency of Canada case definitions for diseases under national surveillance.

Population estimates for this report were collected from the Yukon Bureau of Statistics. Mid-year (June) population estimates were used to calculate annual disease rates.

Chlamydia and gonorrhea cases include genital and extra-genital infections. Infectious syphilis cases include primary, secondary, and early latent forms. Non-infectious syphilis cases include late latent, tertiary, neurosyphilis, congenital, unspecified, and stage pending. Hepatitis B and C cases include chronic, active, and unspecified infections.

Biological sex is used to report cases rather than gender identity.

# References

1. Public Health Agency of Canada. Survey on the impact of COVID-19 on the delivery of STBBI prevention, testing and treatment, including harm reduction services, in Canada. Ottawa: Public Health Agency of Canada; 2022. Pub.: 210294.

2. Public Health Agency of Canada. Infectious syphilis and congenital syphilis in Canada, 2022. Can Comm Dis Rep. 2023; 49(10).

3. Public Health Agency of Canada. Chlamydia, gonorrhea and infectious syphilis in Canada: 2021 surveillance data update. Ottawa: Public Health Agency of Canada; 2023. Available from: https://www.canada.ca/content/dam/phac-aspc/documents/services/publications/diseases-conditions/chlamydia-gonorrhea-infectious-syphilis-2021-surveillance-data/chlamydia-gonorrhea-infectious-syphilis-2021-surveillance-data.pdf. Accessed July 8, 2024.

4. Public Health Agency of Canada. Enhanced surveillance of antimicrobial-resistant gonorrhea in Canada. Ottawa: Public Health Agency of Canada; 2022. Available from: https://www.canada.ca/content/dam/phac-aspc/documents/services/publications/diseases-conditions/enhanced-surveillance-antimicrobial-resistant-gonorrhea-canada-infographic/enhanced-surveillance-antimicrobial-resistant-gonorrhea-canada.pdf. Accessed July 8, 2024.