TB.pdf

TB in Travel Basics and Beyond Elizabeth A. Talbot MD Professor, Infectious Diseases & Int’l Health Dartmouth Geisel School of Medicine NH Deputy State Epidemiologist 2021 Global Epidemiology of TB 10.6M people estimated to have developed TB: 4.5% increase from 2020 – 6.4M reported: 4.1M are ‘missin...

TB in Travel Basics and Beyond Elizabeth A. Talbot MD Professor, Infectious Diseases & Int’l Health Dartmouth Geisel School of Medicine NH Deputy State Epidemiologist 2021 Global Epidemiology of TB 10.6M people estimated to have developed TB: 4.5% increase from 2020 – 6.4M reported: 4.1M are ‘missing’ Increased TB Death 1.6M died from TB Increasing: 1.4M in 2019, 1.5M in 2020 First year-over-year increases in deaths since 2005 Negative epidemiologic impacts of pandemic Decreased diagnoses, treatment, notifications Prolonged infectiousness Neglected LTBI management Exacerbations of social determinants of health as >100M pushed into extreme poverty Who should you advise for pre- and posttravel LTBI testing? The PreTravel Basics for TB How to pretest? How to posttest? Travelers from low to high TB incidence settings Travelers who may have prolonged exposure to TB IGRA or 2-step TST If pre-test is negative, retest 8–10 weeks after returning from travel Pre- and post-test should be same test type Who should you advise for pre- and posttravel LTBI testing? Beyond the Basics How to pretest? How to posttest? Travelers from low to high TB incidence settings Travelers who may have prolonged exposure to TB IGRA or 2-step TST If pre-test is negative, retest 8–10 weeks after returning from travel Pre- and post-test should be same test ype WHO Global TB Report Who should you advise for pre- and posttravel LTBI testing? Beyond the Basics Travelers from low to high TB incidence settings Travelers who may have prolonged exposure to TB How to pretest? IGRA or 2-step TST How to posttest? Pre- and post-test should be same type If pre-test is negative, retest 8–10 weeks after returning from travel “Risk Factors for TB” Increased Risk for TB Infection Prolonged stay in endemic country Close contact to contagious TB case Exposure to high risk populations Healthcare Prison Homeless Persons who inject drugs Increased Risk for Progression to TB Disease People living with HIV People with medical conditions known to increase risk for TB People infected with M. tuberculosis within past 2 years Infants and children 95% in low-TB-incidence settings; not affected by BCG vaccination TST: 97% in populations not vaccinated by BCG; ~60% in populations receiving BCG Varies depending on timing of BCG Summarized in Pai et al, Clinical Microbiology Reviews, 2014 IGRAs’ Favorable Characteristics for Travel? Advantages o Single patient visit o No booster phenomenon o Less likely to have incorrect reading o Not affected by prior BCG vaccination and most NTMs Disadvantages o More expensive up front (1.5x) o Defined time to process blood samples o Limited data on children < age 2 o Reality of conversions/reversions, especially at cutoff of positive and in low risk patients US Guidelines for LTBI Testing Either, if likely LTBI and there is a high risk of progression from LTBI to TB Perform IGRA rather than TST* in individuals >2 years who: o Are likely to be infected, o Have low or intermediate risk of disease progression, o Testing for LTBI is warranted, and o Either have history of BCG vaccination or are unlikely to return to have TST read * TST is an acceptable alternative Lewinsohn DM, Leonard MK, LoBue PA, et al. Official ATS/IDSA/CDC Clinical Practice Guidelines: Diagnosis of Tuberculosis in Adults and Children. Clinical Infectious Diseases. 2017;64(2):e1-e33. TB Risk on a Plane? Risk of TB transmission on airplane is low o No cases of TB disease have so far been reported among those known to have been infected with M. tuberculosis during air travel o Systematic review showed rare reliable evidence of transmission o Dependent on Infectiousness of TB patient Seating proximity Flight duration Host factors WHO guidelines available Bovine TB Lots of reasons to advise people not to consume unpasteurized milk and milk products Bovine TB (M. bovis) is a risk in travelers who consume unpasteurized dairy products in countries where M. bovis in cattle is common Mexico is a common place of infection with M. bovis for US travelers Thanks!