Every year there are an estimated 230,000 childhood deaths from TB. There is an urgent need for novel tests for TB diagnosis in children under 15 years. The Rapid Research in Diagnostics Development for TB Network (R2D2 Kids) and the Assessing Diagnostics at Point-of-care for Tuberculosis in children (ADAPT for Kids) studies seek to reduce the burden of TB worldwide by evaluating faster, simpler, and less expensive TB triage and diagnostic tests for use in children.

The Rapid Research in Diagnostics Development for TB Network (R2D2 Kids) and the Assessing Diagnostics at Point-of-care for Tuberculosis in children (ADAPT for Kids) studies will rigorously assess promising, point-of-care (POC) TB diagnostic tests in clinical studies conducted among children at settings of intended use. There is an urgent need for novel tests for TB diagnosis in children under 15 years because of the challenge of obtaining sputum samples from children and the low sputum bacillary burden among children with TB even when a sample is obtained. This creates delays in diagnosis and treatment initiation, and is a major contributor to the 230,000 childhood deaths from TB each year. Therefore, a non-sputum biomarker-based test has been ranked among the highest priority target product profiles for new TB diagnostics. If inexpensive and simple to perform, such a diagnostic tool could have significant impact by facilitating rapid diagnosis and TB treatment in children. The studies will evaluate the sensitivity and specificity of novel diagnostic tests in children in reference to NIH consensus definitions for childhood TB. In addition, the usability and acceptability of the novel TB diagnostic tests will be assessed through direct observations and surveys of routine health workers.

Participant eligibility criteria:

Participants will include children (age <15 years) who present to care with:

A. 2 or more of the following:

• Unexplained cough for any duration
• TB contact or tuberculin skin test or interferon gamma release assay positive
• Abnormal chest X-ray (any abnormality) OR

B. Any one of criteria A AND any one of the following:

• Unexplained weight loss OR unexplained failure to thrive OR Severe Acute Malnutrition
• Unexplained fever ≥2 weeks
• Unexplained lethargy or reduced playfulness ≥2 weeks

The study will exclude participants who:

1. Completed preventive or active TB treatment within the past 12 months (to increase TB prevalence and reduce false-positive results, respectively);
2. Have taken any medication with anti-mycobacterial activity for any reason for greater than 3 days at the time of enrollment (to reduce false-negatives);
3. Are unable to return for follow-up visits; or
4. Whose parents/guardians are unwilling to provide informed consent or who are unwilling to provide assent if applicable (age determined by local IRB)

Assessment of the usability of novel TB tests:

The study will also include health workers at each clinical site who are 1) aged ≥18 years and 2) involved in routine TB testing (collecting specimens for or performing TB tests). Personnel who are unwilling to provide informed consent will be excluded.