Air-travel related TB incident follow up â€“ effectiveness and outcomes: a systematic review
LauraÂ Maynard-Smith,Â Colin StewartÂ Brown,Â Ross JeremyÂ Harris,Â PeterÂ Hodkinson,Â SurinderÂ Tamne,Â Sarah R.Â Anderson,Â DominikÂ Zenner
European Respiratory JournalÂ 2020;Â DOI:Â 10.1183/13993003.00013-2020
BackgroundÂ The World Health Organization (WHO) recommends following up passengers following possible exposure to a case of infectious tuberculosis (TB) during air travel. This is known to be time consuming and difficult, and increasingly so with higher numbers of flights and passengers to and from countries with high TB endemicity each year.
ObjectivesÂ This paper systematically reviews the literature on contact tracing investigations following a plane exposure to active pulmonary TB. Evidence for in-flight transmission was assessed by reviewing the positive results of contacts without prior risk factors for latent TB.
Data sources & EligibilityÂ A search of Medline, EMBASE, BIOSIS, Cochrane Library and Database of Systematic Reviews was carried out, with no restrictions on study design, index case characteristics, duration of flight or publication date.
ResultsÂ Twenty-two papers were included, with a total of 469 index cases and 15â€Š889 contacts. Only 26.4% of all contacts identified completed screening following exposure. The yield of either a single positive tuberculin skin test (TST) or a TST conversion attributable to in-flight transmission is between 0.19% (95%CI 0.13â€“0.27) and 0.74% (95%CI 0.61â€“0.88) of all contacts identified (0.00%, 95%CI 0.00â€“0.00 and 0.13%, 95%CI 0.00â€“0.61 in random effects meta-analysis).
LimitationsÂ The main limitation is heterogeneity of reporting.
Conclusions and implications of key findingsÂ The evidence behind the criteria for initiating investigations is weak and it has been widely demonstrated that active screening of contacts is labour intensive and unlikely to be effective. Based on our findings, formal comprehensive contact tracing may be of limited utility following a plane exposure.
This manuscript has recently been accepted for publication in theÂ European Respiratory Journal. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of theÂ ERJÂ online. Please open or download the PDF to view this article.
Conflict of interest: Dr. Maynard-Smith has nothing to disclose.
Conflict of interest: Dr. Brown has nothing to disclose.
Conflict of interest: Dr. Harris has nothing to disclose.
Conflict of interest: Dr. Hodkinson has nothing to disclose.
Conflict of interest: Dr. Tamne has nothing to disclose.
Conflict of interest: Dr. Zenner has nothing to disclose.
Conflict of interest: Dr. Anderson has nothing to disclose.
- ReceivedÂ January 5, 2020.
- AcceptedÂ October 27, 2020.
- Copyright Â©ERS 2020