(2) what definition his Department uses of (a) typical and (b) atypical tuberculosis.
The terms typical tuberculosis and atypical tuberculosis are not formally recognised and are therefore not defined.
We have interpreted typical tuberculosis to mean “tuberculosis”—a clinical disease that is defined by either:
confirmation by laboratory culture of a sputum or other sample of infection, due to Mycobacterium tuberculosis complex (including M. tuberculosis, M. bovis and M. africanum).
or
in the clinician’s judgment in the absence of culture confirmation, clinical and/or radiological signs and/or symptoms compatible with tuberculosis, which are treated with a full course of anti-tuberculosis treatment.
We have interpreted “atypical tuberculosis” to mean disease caused by “atypical mycobacteria”, or non-tuberculous mycobacteria. It refers to infections caused by all other organisms of the family Mycobacteria excluding tuberculosis (caused by M. tuberculosis complex) and leprosy (caused by Mycobacterium leprae). Most of these organisms are ubiquitous in the environment and do not usually cause disease in humans except in individuals whose immune system is compromised. There are over 125 known “non-tuberculous mycobacteria” (the preferred term to describe these organisms).
Disease or infection due to non-tuberculosis mycobacteria is not currently notifiable and therefore there are no reliable data on the number of cases in the last five years.
The number of cases of drug-resistant tuberculosis (TB) by strategic health authority are shown in the following table, with data from 1998-2006.
The Enhanced Tuberculosis Surveillance system (ETS) started in 1999. Prior to this, National TB Surveys were carried out every five years and this provided data for 1998.
SHA 1998 1999 2000 2001 2002 2003 2004 2005 2006 East Midlands 9 11 11 19 18 18 19 15 22 East of England 9 <5 9 19 16 17 17 29 19 London 82 97 107 132 165 191 185 179 203 North East <5 <5 <5 <5 <5 <5 <5 <5 <5 North West 11 10 17 14 20 12 20 26 18 South Central 15 16 7 <5 9 10 13 11 14 South East Coast <5 5 9 7 13 8 8 9 13 South West 11 7 5 9. 6 7 7 5 8 West Midlands 20 20 19 21 36 20 26 25 21 Yorkshire and the Humber 9 5 8 7 5 18 26 31 27 Source: ETS, Health Protection Agency, as at 16 November 2007.