ID 2 Latent Tb Infection and Screening, Dr Dominik Zenner

Speaker key

IV Interviewer

DZ Dominik Zenner

DZ My name is Dominik Zenner and I’m Head of TB Screening for Public Health England and I talked about the latent TB testing and treatment programme amongst migrants in the UK, primary care based, which is currently being rolled out nationally.

IV Why is screening for latent TB so important?

DZ Tuberculosis rates in the UK are fairly high and three-quarters of TB in the UK occur amongst people born abroad in high burden TB countries. A lot of that TB, in fact, more than 80%, occurs as a result of re-activation of latent TB infection LTBI. Effective treatment is available for latent TB infection and it is important to be able to offer this to migrants from high incidence countries to prevent them from getting active TB.

IV Who should be invited in to the screening programme?

DZ It is those people that were born or spent significant time, more than six months, in very high incidence countries, those that have an incidence of 150 per 100,000 or above, or sub-Saharan Africa, who have been in this country for less than five years and who are aged 16-35 and haven’t been previously screened.

IV Can anyone else be screened?

DZ Obviously there are NICE recommendations and within these recommendations, for example, children less than 16 years old should also be offered screening.

IV How is it done?

DZ It is done with an Interferon-Gamma Release Assay IGRA test, which is a single blood test. There are two available at the moment: Quantiferon which is ELISA test, and T-Spot, which is an LE spot test; both measure the immune reaction to mycobacterium tuberculosis.

IV Is it done at all the local hospitals?

DZ No, it will get sent to a large lab who processes all the samples in the region and who also take care of the transport, including the couriers.

IV What can the results show?

DZ The results will be either positive, negative or equivocal. The equivocal results need re-testing; patients with negative results will just need advice; and those with positive results will need referring on to the TB services.

IV Can you get false positives or negatives?

DZ The chance of being false negative is relatively low. There is a chance to be false positive, although that is much lower than the conventional skin test that we used to do, and it’s also mitigated against by picking the right target population.

IV What does a GP or nurse do if the result is positive?

DZ Well, the first thing is to inform and advise the patient and what might be helpful is to use the national leaflet, which is available through the CCG or will be available on the website, and then, of course, to rule out that the patient has active TB and to refer the patient on to the TB services for further work-up and treatment of LTBI.

IV Where can GPs find out more?

DZ There are a number of stakeholder events now happening. Also, we have a lot of materials on our website, on our Public Health England website, and I’m very happy for people to contact me on the .

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