Preferences for Tongue Swab versus Sputum Collection for Tuberculosis Testing: A Multi-Country Survey

Area of Science:

• Global Health
• Infectious Disease Diagnostics
• Molecular Diagnostics

Background:

• Sputum collection for tuberculosis (TB) diagnosis is challenging for vulnerable populations, including children, people living with HIV, and individuals with poor sputum production.
• Tongue swab-based molecular testing presents a less invasive and potentially more acceptable alternative for TB diagnosis.
• Limited person-centered research exists on the acceptability of tongue swab testing compared to traditional sputum collection.

Purpose of the Study:

• To assess the acceptability and preference for tongue swab versus sputum collection among individuals with presumptive tuberculosis (TB).
• To evaluate the potential of tongue swab diagnostics to overcome barriers in TB testing.
• To gather data on diagnostic preferences across diverse demographic and clinical groups in multiple countries.

Main Methods:

• A pragmatic survey was conducted across eight countries with individuals presenting with presumptive TB at primary care facilities.
• Participants provided both tongue swab and sputum samples for TB testing.
• A 5-10 minute survey captured participant preferences regarding sample collection methods.

Main Results:

• A total of 1,297 participants were enrolled, with a median age of 43 years; 45% were female and 13% were HIV-positive.
• A significant majority (61%) preferred tongue swab collection over sputum collection (22%), with 17% having no preference.
• Preference for tongue swabs remained consistent across demographic and clinical subgroups, though country-level variations were observed (47% in South Africa to 74% in Zambia and Nigeria).

Conclusions:

• A strong preference for tongue swab collection over sputum collection was observed in individuals with presumptive TB.
• This finding highlights the potential of tongue swab diagnostics to enhance TB testing accessibility and overcome existing collection barriers.
• The study supports the adoption of tongue swab testing as a patient-centered approach to improve timely TB diagnosis, especially for difficult-to-test populations.