USA TB Testing of Foreign Born Persons.

The following was uncovered and reported by "doc-gt" over here. I am re-reporting the essence of it because it is very important.


The (US) Advisory Council for the Elimination of TB (ACET) is convened by the CDC with the specific purpose of advising the CDC. Their meetings are open to the public and the minutes of their meetings are publicly published. The most recent minutes (October 2009) are available here.


There is a lot of information in the minutes but of particular interest is the Update by the Foreign-Born Working Group (FBWG) starting at page 19. The FBWG is tasked with revising the "Recommendations for Prevention and Control of Tuberculosis Among Foreign-Born Persons". 


It seems to be clearly accepted that the current processes are not working - while TB prevalence rates in the general US population are decreasing, the rates amongst the Foreign Born Persons (FBPs) are increasing.

"CDC acknowledged the need for a new approach to TB control in FBPs because the two most broadly implemented strategies have not significantly impacted the incidence of TB among FBPs."

"Most foreignborn TB cases are due to reactivation of infection acquired prior to arrival to the United States. The 6.9 million FBPs with LTBI must be addressed to achieve TB elimination."

Reading previous minutes, it is clear that there has been much discussion on how these problems should be managed. It is only in these minutes that a full consensus has been arrived at.

"One, what FBPs should be screened? The consensus panel agreed that each individual born in a TB-endemic country should be screened at least once for LTBI.

This recommendation would include all persons born in every foreign country with the exception of Australia, Canada and Western Europe."

and

"Two, what methods should be implemented to screen FBPs? The consensus panel agreed that IGRAs are the preferred screening method for most FBPs due to their higher specificity in persons who have received BCG vaccination."

Putting all of that together they are saying that all FBPs (except for the Western Europeans, Canadians and Australians) should be tested for Latent TB and the preferred method for doing this is the IGRA.


According to the minutes there are currently 6.9m FBPs with Latent TB in the US.


If we add this recommendation to our best intelligence of the shortly forthcoming CDC Guidelines we now have:


IGRA diagnosis is preferred for:


- those who have been BCG vaccinated.
- those who are likely to not return for reading of a TST.
- those who are at low risk of TB
- all Foreign Born Persons.


If we further assume that Health care Workers will be tested with IGRA (a not unreasonable assumption) then there isn't much left! It seems that Dr. Masae Kawamurra's prediction of the TST fading into a very minor role is very likely to come true.