by Kate Ebbutt


Positivity rate seen in the asymptomatic ethnic minority cohort


Symptomatic cohort positivity rate


Positivity rate in people under 25

Lesley Navarantne (Maidstone & Tunbridge Wells NHS Trust), Rachel Marsden (Maidstone & Tunbridge Wells NHS Trust), Mark Clune (Preventx)


Online asymptomatic screening includes chlamydia, gonorrhoea, Syphilis, HIV, Hepatitis B and C. Testing for Trichomonas Vaginalis (TV) is not included as this is usually performed in symptomatic patients referred into clinic.

During the Covid-19 pandemic, this sexual health service implemented an online triage for symptomatic female users. Females who self-identified as having vaginal discharge were offered additional PCR testing for TV. Higher positivity rates for other infections in racially minoritised groups locally, meant that asymptomatic females from these groups were also offered TV screening to assess rates of infection.


In one local authority, two cohorts of patients were tested online through an STI testing service. Cohort 1: females from all ethnic groups who indicated having vaginal discharge; Cohort 2: asymptomatic females who identified being from a racially minoritised group. The sensitivity and specificity of the PCR test was 100% and 99.4%.

TV positivity rate was compared between ethnicity, age, deprivation level, and urban/rural classification for 2188 samples collected between 15 March and 23 August 2021.


Overall TV positivity rate was 2.5% (n=55) across both cohorts. A positivity rate of 2.3% (n=16) was seen in the asymptomatic ethnic minority cohort, and higher in Caribbean (3.4%) and White and Black African (6.5%) users, similarly in <25 years (2.2%) and > 25 years (2.3%). The symptomatic cohort positivity rate was 2.7% (n=36) and was higher in women from racially minoritised groups (3.1%) and people > 25 years (3.8% vs 1.5%).


TV positivity rates are consistent with using an online triage to determine symptoms and provide patients with the appropriate tests.

TV testing in asymptomatic patients identified infections in racially minoritised users. Further investigation is needed to understand if this may be similar in other asymptomatic populations and geographical areas.

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About the author:

Kate Ebbutt is the Head of Marketing and Communications for Preventx