Several laboratories across the US are reporting increased volume and staffing shortages that are resulting in significant delays to tuberculosis testing when using “TB Gold,” also known as QuantiFERON blood testing. The labs are not able to ship received samples or divert new samples to other lab locations due to the fragility of the sample and required testing equipment. Typical turnaround time is 3-4 days, but turnaround times of 4-9 days are currently being reported by some national lab chains.
Other options exist for employers, especially in healthcare where TB testing is critical and time sensitive:
Purified Protein Derivative (PPD) skin testing does not require a laboratory but has an automatic 3+ day turnaround time because the collection clinic cannot read the test before the completion of the 48-72 hour waiting period. The employee must return to the clinic after 48-72 hours for the medical personnel to inspect any possible skin reaction, which could indicate a positive result. The clinic then must follow up by submitting results. Some individuals who’ve been BCG vaccinated may have a false positive.
TSPOT is a different type of blood test for TB. TSPOT testing is processed by a single laboratory that does not process TB Gold tests. This lab is currently running on time. The test is approved for people who have been BCG vaccinated and has very high sensitivity and specificity. Turnaround time is currently 3-4 days on average.
Vault offers all three types of TB testing as well as chest x-rays to its clients. Vault clients that are having difficulty finding a TB test for an employee that meets turnaround time requirement should reach out to Vault’s account management team at acctmgr@vaulthealth.com. The account management teams can also help with amending these options into your existing contract.
More information from the CDC:
TB Screening and Testing of Health Care Personnel | TB | CDC
Read our blog:
Should TB testing be part of your employee screening program?