1. Surveillance of Tuberculosis
in Spain
Mª Elena Rodríguez Valín
Centro Nacional de Epidemiología
Instituto de Salud Carlos III
Madrid (Spain)

2. Background Pulmonary TB 1930-1996 Yes No Respiratory TB 1997-present
Disease
Year
Aggregate data
Place / Week
Individualised data
Pulmonary TB
Yes No
Respiratory TB
1997-present
Meningeal TB
TB of any site
2003
In Spain, pulmonary TB is a statutorily notifiable disease since Since 1930 we have data aggregated by place and epidemiological week available . Since 1964 the data are available in electronic format.
In 1995, the National Epidemiological Surveillance Network was established, and both respiratory and meningeal tb were classified as statutorily notifiable diseases in accordance with specific reporting guideliness and case definitions. The case notification form was improved, and a specific set of variables was included in order to follow the international reporting procedures. These changes were implemented in In consecuence, since 1997 we have data about both respiratory and meningeal TB available.
In 2003 a new case definition was approved, which includes TB of all sites. This definition will be implemented in 2004.

3. Cases of respiratory TB reported to the Statutorily Notifiable Disease System. Spain, 1964-2002
The number of cases of respiratory TB reported to the Statutorily Notifiable Disease System since 1964 have showed a decrease, followed by a big increase in the eighties, probably related to the AIDS epidemic. Since the nineties the number of cases and the incidence rates have showed a downward trend.

4. Cases of meningeal TB reported to the Statutorily Notifiable Disease System. Spain,1997-2002
Regarding meningeal TB, we have available data since 1997, after the inclusion of this form of TB in the list of statutorily notifiable diseases. It seems that the number of cases is increasing, but until we have more information it is difficult to assess this trend.

5. Source: Medical practitioners. Mandatory notification of TB
TB Reporting System
Source: Medical practitioners. Mandatory notification of TB
Local level
Area level
Autonomous Region
National level
National Centre of Epidemiology
International level
In order to understand the functioning of the reporting system, a brief description of the administrative structure of the Spanish State is necessary. Spain is divided into 17 Autonomous Regions and two Autonomous cities, each of them with their own responsibilities in health. Most of the Autonomous Regions have TB control programs, but there is not a National Program.
Medical practitioners have to notify the TB cases to the local level, through a case notification form. The notification is mandatory. The local level sends the data to the area level, and each Autonomous Region collects the information of their areas. The National Centre of Epidemiology is the National Institution that receives the data from all the Autonomous Comunities, and is in charge of the international dissemination of the country´s information.
The National Ministry of Health is responsible for coordination.
It is important to remark that the case definition, the case reporting form and the reporting procedures have been agreed between the Ministry of Health and the Autonomous Communities.

6. TB Case definition*
A clinician´s judgement that the patient´s signs and/or symptoms are compatible with respiratory or meningeal tuberculosis
AND
A clinician´s decision to treat the patient with a full course of anti-TB treatment, usually with two or more drugs.
Definite TB case: a patient with culture-confirmed disease due to M. tuberculosis complex, or smear positive for acid-fast bacilli (AFB) in an appropriate sample, if culture is not feasible.
The definition of a case of tuberculosis up to thel present is the following:
A clinician´s judgement that the patient´s signs and/or symptoms are compatible with respiratory or meningeal tuberculosis
AND
A clinician´s decision to treat the patient with a full course of anti-tb treatment, usually with two or more drugs.
A definite tb case: a patient with culture-confirmed disease due to M. tuberculosis complex, or smear positive for acid-fast bacilli (AFB) in an appropriate sample, if culture is not feasible.
In 2003 a new case definition has been approved, which includes TB of all sites.
* In 2003 a new definition has been approved, which includes TB of any site

7. Individualised case reporting
Basic Data Set: age, sex, local code, week/year, disease, case classification.
Specific Data Set *:
site of disease (respiratory/meningeal)
previous anti-TB treatment status
geographic origin
culture results
smear results
HIV status
Others
* In accordance with Eurotb
In the context of individualised case reporting, the variables included are divided into two groups:
A basic data set, for all the mandatorily notifiable diseases, and
A specific data set, in accordance with international requirements, which includes : site of disease (respiratory/meningeal), previous anti-tb treatment status, geographic origin, culture and smear results, and HIV status.

8. National Incidence rate: 18.48/100,000
Estimated incidence rates of respiratory TB by Autonomous Regions. Spain, 2002.
Now I am going to speak about the distribution and characteristics of the TB cases reported in 2002.
This figure shows the estimated incidence rates of respiratory TB by Autonomous regions, based on individualised case reporting. The National rate of respiratory TB for 2002 is 18.4 cases/100,000 population. We can see that there are big differences between the regions, with the highest rates in Galicia, Ceuta, the Basque Country and Melilla.
National Incidence rate: 18.48/100,000

9. National Incidence rate: 0.33/100,000
Estimated incidence rates of meningeal TB by Autonomous Regions. Spain, 2002.
In this figure we can see the incidence rates of meningeal TB by Autonomous regions. The National rate of meningeal TB for 2002 is 0.3 cases /100,000 population. The geographic distribution is very similar to respiratory TB, with the highest rate in Galicia, followed by Madrid.
National Incidence rate: 0.33/100,000

10. Characteristics of the cases (2002)
Respiratory TB
Total number of cases:7,493
Treatment status
Sex
Regarding the characteristics of the cases reported in 2002:
The total number of cases of respiratory TB is nearly 7,500, which represents 98 % of all the reported cases.
67% of them are males
The classification of the cases by previous anti-TB treatment shows that almost 70 % of them are new cases, and nearly 5% are recurrent cases. We should take into account that in 27 % we do not know the previous status of treatment.

11. Cases of respiratory TB by age group and sex.
Spain, 2002
N = 7,431
In this figure we can see the number of cases of respiratory TB by age group and sex. We can see that, in males, the highest number of cases is in the 35 to 44 age group, followed by the over 65s.
In women, the case distribution is not exactly the same. We can see that the highest number of cases is in the 25 to 34 age group, followed by the 15 to 24.
In consequence, the mean age is higher in males (44 years) than in females (38 years), and this difference has statistical significance.
mean age: years (males), years (females)

12. Respiratory TB, 2002 Laboratory results All cases (7,493)
Information about 5,683 cases (77 %)
2,358 cases (41 %) smear and culture positive
Total smear positive: 3,520 (62 %)
Total culture positive: 3,820 (67 %)
New cases (5,151)
Information about 4,412 cases (86 %)
1,768 cases (40 %) smear and culture positive
Total smear positive: 2,660 (60 %)
Total culture positive: 2,948 (67 %)
Regarding laboratory results of respiratory TB, we have information about 77 % of all cases. Of these, 41 % are both smear and culture positive. The total number of smear positive cases is 3,520.
If we consider only new cases, the proportion with laboratory results is higher (86 %). Of these, 40 % are both smear and culture positive, and the number of smear positive cases is 2,660.

13. Characteristics of the cases (2002)
Meningeal TB
Total number of cases:133
Sex
Treatment status
Now I am going to show the characteristics of the meningeal TB cases. The proportion of males is 60 %.Regarding treatment status almost 80 % of cases are new. However, the number of cases with unknown treatment status is 50 %.

14. Cases of meningeal TB by age group and sex.
Spain, 2002.
N = 133
The distribution of cases by age group is similar to that of respiratory TB, although here the proportion of cases in the under five age group is greater. The mean age is very similar in males and females.
mean age: years (males), years (females)

15. Meningeal TB, 2002 All cases (133) New cases (78)
Laboratory results
All cases (133)
Information about 52 cases (39 %)
3 cases (6 %) smear and culture positive
Total smear positive: 14 (27 %)
Total culture positive: 17 (33 %)
New cases (78)
Information about 43 cases (55 %)
3 cases (7 %) smear and culture positive
Total smear positive: 14 (32 %)
Total culture positive: 15 (35 %)
One difference between respiratory and meningeal TB is with respect to laboratory results. In the case of meningeal TB there is a much higher proportion of cases without results, both in all cases and in new cases, although in new cases the completeness of the information is better. So, there are results available in about 40 % of all cases and 55 % of new cases.

16. Characteristics of the cases (2002)
Special groups
HIV status
HIV positive cases
Number: 926
Sex: 75 % (686) males
Previous treatment status:
72 % (671) new cases
Country of birth:
4.5 % (42) outside Spain
There are two groups of special interest for which we have data based on individualised case reporting: HIV positive and foreign origin cases.
Regarding HIV status, we can see that almost 50 % of cases do not have information available. The number of HIV positive cases reported is 926, which represents 12 % of all cases. The principal characteristics of these HIV positive cases are shown to the right of the slide: 75 % of them are males, 72 % are new cases and nearly 5 % were born outside Spain.
N = 7,626

17. TB/HIV positive cases by age group and sex.
Spain, 2002.
N = 916
The distribution of HIV positive cases by age group and sex shows a different pattern from all TB cases. First, the proportion of males is higher, and another difference is that most of cases are in the and age groups.
the mean age is higher in males (40 years) than in females (36 years), and this difference has statistical significance.
Mean age: years (males), years (females)

18. TB/HIV positive cases, 2002 Laboratory results
All cases (926)
Information about 839 (90 %) cases
373 (44 %) cases both smear and culture positive
total smear positive: 489 (58 %)
total culture positive: 631 (75 %)
New cases (671)
Information about 628 (93 %) cases
292 (46 %) cases both smear and culture positive
total smear positive: 362 (57 %)
total culture positive: 490 (78 %)
Regarding laboratory results, it is observed that the completeness of the information is very good. In HIV positive cases, there are laboratory results for 90 % of cases, and this proportion is higher in new cases.

19. Characteristics of the cases (2002)
Special groups
Country of birth
Number: 444
Sex: 61 % males
Type of disease:
98 % (436) respiratory TB
Previous treatment status:
34 % (153) new cases
HIV status:
9 % (42) positive
Born outside Spain
Which respect to the geographic origin of cases, there is information on 3,570 out of 7,626 cases. There are 444 cases born outside Spain reported, 61 % of them males, most of them with respiratory TB, and 9 % HIV positive. 153 are new cases.
N = 7,626

20. TB cases of foreign origin
by age group and sex.
Spain, 2002.
N = 444
The age distribution shows that most of these cases are young people, with mean age 33 in males and 30 in females.
mean age: years (males), years (females)

21. Characteristics of the Reporting System
Conclusions
Characteristics of TB cases
Regional differences in incidence rates
Almost 70 % new cases
Rates higher in males
Age distribution: 62 % of all cases under 45
HIV positives: predominantly males, 77 % of all cases under 45
Laboratory information better in new and HIV positive cases
Characteristics of the Reporting System
Individualised reporting of cases is useful for showing the principal characteristics of TB in Spain
Needs improving:
Information about country of origin
Information about HIV status
Laboratory information in meningeal TB cases
With these results, we can conclude that
the distribution of TB incidence rates in Spain shows differences between the Autonomous Comunities,
which respect to the cases, nearly 70 % are new cases,
the highest rates are in males.
More than 60 % of cases are young or middle-aged people.
These sex and age characteristics are more marked in HIV positive cases.
Regarding the reporting system, we can conclude that individualised reporting is useful for showing the principal characteristics of TB in Spain and that this information has improved since the implementation of this kind of reporting, although I have only shown results of one year.
It is necessary to improve some aspects, like the completeness of information about country of origin, HIV status, and laboratory results in meningeal TB.

22. Improvements
Site of disease: Need to collect information about TB of all sites
New case definition (2003)
Outcome of treatment: standard definitions according to the WHO European Region.
Finally I would like to remark on some aspects that needed improvement, and that have been taken into account in the new guideliness approved this year by agreement between the Autonomous Comunities and the Ministry of Health.
In first place, it was neccesary to collect information about all sites of TB, for a better understanding of the epidemiological situation, and to permit international comparison. In consecuence, a new case definition has been approved this year, which includes TB of all sites. It will be implemented in 2004.
Which respect to the outcome of treatment, there were different criteria in use among the Regions, and the information at National level was very incomplete and inaccurate. In the new guideliness, the different categories have been defined clearly, in accordance with the WHO European Region.
We expect that with these improvements the information about the TB situation in our country will be more complete and in accordance with international requirements.
Thank you very much for your attention
New guideliness approved in 2003