Table 1.

COVID-19, sexually transmitted infections and tuberculosis, and the approach to UK contact tracing

COVID-19Sexually transmitted infectionsTuberculosis (TB)
Biology of diseaseShort incubation, rapid spread, little latency between infection and disease. Most infected individuals get symptomatic disease, asymptomatic individuals can be infectiousVaried biology with different infections. Most transmission by symptomatic individuals, but high infectivity may be early in disease with minimal symptoms (eg primary HIV infection and seroconversion)Most exposed individuals are not infected; most infected individuals do not get symptomatic disease
Knowledge of disease and control measuresNovel pathogen, rapidly evolving understanding of pathology and treatment optionsConditions well understood, multiple methods of prevention and treatment generally availableLong history of research into disease, transmission and treatments
Mechanism of spreadShort exposure for infection (minutes). Believed to be primarily droplet-spread, although role of airborne transmission and contaminated surfaces unclearSexual contactPrimarily aerosol. Prolonged (>8 hours) contact required for transmission
Interventions to prevent transmissionContact tracing with isolation reduces onward transmission. No specific treatment available to prevent onward transmissionIdentification of cases can allow preventative measures (eg condoms)
Treatment of conditions prevents onward transmission (eg use of antiretroviral therapy for HIV)
Contact tracing detects incident disease, & latent (asymptomatic) infection
Treatment of TB disease and latent TB cures or prevents disease, and reduces further transmission
Contact tracing approachContact tracing by large workforce (but mostly with less specialist skill-set), largely independent of NHS public health servicesAnonymous tracing often used, national electronic system within NHSPerson-to-person, networks of skilled professionals within NHS
InfrastructureNewly created structure with significant private sector inputSexual health services part of health system, although with sensitive data not shared with other health systemsBuilt within NHS networks