Estimating TB incidence: the study

G.B. Migliori WHO Collaborating Centre for Control of TB and Lung Diseases, Fondazione S. Maugeri, IRCCS, , Outline:

• Italy, epidemiology and pitfalls of the notification system • Rationale for the study • Varese, the setting • Methods • Results • Discussion of results and exercise Italy, very low TB case- fatality rate (x 100,000) Italy, very low incidence of TB notified cases (x 100,000)

drugs

rifampicin Italy: stable incidence (7/100,000), intra-Regional differences (2 Regions not notifying)

0-2/100.000 3-5/100.000 6-8/100.000 9-14/100.000

ITALY: 7/100,000 TB in Italy, 2004

- All cases notifications: 7 per 100,000 pop - SS+ notifications: 3 per 100,000 pop - Notified TB/HIV+: <1 per 100,000 - Proportion of new ss+: 37% among new pulmonary cases - MDR-TB cases: 9 (new), 24 (All) Aim of the exercise

• To discuss the possibility of validating a surveillance system through collection of parallel independent data • To calculate true incidence and other relevant parameters • To discuss the results achieved in Varese Province, Italy • To discuss pros and contras of implementing this methodology The Varese study… Background… The setting… Varese 0-2/100.000 3-5/100.000 6-8/100.000 9-14/100.000

Rome

Varese Province: a rich territory between Milan and the Swiss border Methods CSS (Compulsory Surveillance System):

• TB notifications compulsory within communicable diseases • Flow: from notifying physician to local public health Unit to Region to MOH • Form: section A (23 items on demographics) and B (microbiology, diagnostic criteria, localization) Methods (cont.) VSS (Varese Surveillance System): • A responsible person in each health unit (including 10 laboratories) • Flow: from notifying staff to study coordinator for teh calendar year 1992 • Group discussion for data validation, strict supervision • Form: 55 items (all CSS ones + 10 more on diagnostic criteria and risk) • Comparison CSS vs VSS Results 1: Results 2: Results 3: Results 4: Results 5: Exercise: comment the results Guide for discussion

1) Does an alternative system exists currently in your country to verify the data? For example, the files in the health centres at the periphery level? 2) What is your opinion of the study? Please discuss this in the context of how useful you find it, whether it is relevant in the context of your country and the feasibility to replicate it in your country? 3) Which are the main conclusions we can draw from the study on the CSS?