Eurosurveillance

ECDC

Tuberculosis in the Nordic and Baltic countries in 2006

 Rediger
  Published: 19.12.08 Updated: 19.12.2008 11:07:15

K. Kutsar, Health Protection Inspectorate, Tallinn, Estonia

Citation: Kutsar K. Tuberculosis in the Nordic and Baltic countries in 2006. EpiNorth 2008 Vol9 No 3. p. 93-96

Introduction
Estonia, Latvia and Lithuania are among the 18 high-priority countries designated in the Plan to Stop TB in the WHO European Region, while the neighbouring Nordic countries (Denmark, Finland, Iceland, Norway and Sweden) have some of the lowest incidence rates of tuberculosis in the world (1-4). Based on published reports for the year 2006, we reviewed the tuberculosis situation in the Nordic and Baltic countries.

Methods
We used data from reports by national correspondents to the Euro TB network and to the WHO, (for 2006) and other published reports (1-4). The estimated coverage of the surveillance systems is 99% in Denmark, 95% in Finland, 95% in Norway, 80% in Estonia and 100% in Latvia and Lithuania. The figure for Estonia may be due to under-reporting in sub-groups of immigrants, prisoners, children, HIV/AIDS patients and the elderly, and in certain regions of the country (for example East-Virumaa) (2).

Results
There was a wide variation in incidence rates between the countries in the region in 2006 (Table 1).

Table 1. Incidence of tuberculosis in 2006 and changes in the period 2002-2006 in the Nordic and Baltic countries (2)

Country / Страна

Incidenceper 100 000 population / Заболеваемость на  100 000 населения

Percentage change in the period 2002-2006/ Изменения в % за период

2002-2006  

Estonia / Эстония

34.0

- 10.3

Latvia/ Латвия

58.0

- 7.4

Lithuania / Литва

75.1

- 2.0

Denmark / Дания

6.9

- 2.6

Finland / Финляндия

5.7

- 10.4

Iceland / Исландия

4.4

+ 26.8

Norway / Норвегия

6.3

+ 4.6

Sweden / Швеция

5.5

+ 5.4

In Denmark, 57% of cases were of foreign origin (mainly Asia and Africa), in Finland12 % (Asia and Africa), in Sweden 72% (Asia, Africa and the Balkans), in Norway 81% (no data on regions available), in Iceland 77% (Asia and Africa), in Estonia 15% (Eastern Europe), in Latvia 5% (Eastern Europe) and in Lithuania 3% (Eastern Europe) (2).
Domestic cases tended to be somewhat older in the Nordic than in the Baltic countries (Table 2).

Table 2. Distribution of age groups among tuberculosis cases of domestic origin in the Nordic and Baltic countries, 2006 (2)

Country / Страна

Agegroup, inpercentages / Возрастная группа, проценты

0-4 years / лет

5-14 years / лет

15-44 years / лет

45-64 years / лет

>64 years / лет

Estonia / Эстония

0

2

49

39

10

Latvia/ Латвия

3

3

51

33

9

Lithuania / Литва

1

3

43

39

13

Denmark / Дания

1

1

39

39

19

Finland / Финляндия

0

0

10

29

61

Iceland / Исландия

0

0

33

33

33

Norway / Норвегия

0

13

18

25

45

Sweden / Швеция

1

6

19

14

61

In the cases of foreign origin, the age groups with the highest incidence rates were 15-44 years (67%) in Denmark, 15-44 years (89%) in Finland,15-44 years (71%) in Sweden,15-44 years (75%) in Norway, 15-44 years (90%) in Iceland, 15-44 years (33%) and 45-64 years (40%) in Estonia, 14-44 years (28%) and 45-64 years (55%) in Latvia, and 15-44 years (29%) and 45-64 years (49%) in Lithuania (2).

Clinical and microbiological characteristics
Pulmonary tuberculosis accounted for 54% of cases in Iceland and 92% in Estonia (Table 3). Around half of the pulmonary cases in the region were smear-positive, with a range of 27% in Norway to 62% in Lithuania. The incidence of smear-positive cases, however, showed greater variation (Table 3).
The percentages of cases confirmed by culture varied from 70 in Lithuania to 92 in Iceland (Table 3).
Most culture-confirmed cases were caused by M. tuberculosis (Table 3). In Estonia 38.6% of identified species was M. tuberculosis, while in 61.4% of cultures the species was not identified (2).

Table 3. Characteristics of pulmonary tuberculosis cases in the Nordic and Baltic countries, 2006 (2)

Country /Страна
Percentage pulmonary cases /Долялегочныхслучаевв %
Smear-positive pulmonary cases / Случаилегочноготуберкулезасположительныммазком
Percentage of culture-confirmed cases / Доляслучаев,  подтвержденныхпосевом 
Percentage of M. tuberculosis complex species / Комплекс M. tuberculosis потипамв %
Incidence per 100 000 /Заболеваемость  на 100 000
Percentage of all pulmonary cases / Долялегочныхслучаевв %
M. tuberculosis
M. africanum
M. bovis
Estonia /Эстония
92
14.0
45
76
38.6

 

 

Latvia / Латвия
91
27.6
52
75
100

 

 

Lithuania / Литва
87
40.5
62
70
100

 

 

Denmark / Дания
73
2.5
50
80
98.0
1.0
0.7
Finland / Финляндия
71
1.9
47
91
100

 

 

Iceland / Исландия
54
1.3
57
92
91.7

 

8.3
Norway / Норвегия
64
1.1
27
77
99.6
0.4

 

Sweden / Швеция
64
1.2
35
80
99.2

 

0.5

Tuberculosis, HIV infection and AIDS
The percentage of tuberculosis cases with positive HIV serostatus was highest in Iceland (15.4%, but only two cases) (Table 4). In Estonia the percentage has increased since 2000, from 0.1% to 9.0% and in Latvia from 0.7% to 3.4%. Both countries experienced a steep increase in HIV infection in the early years of the present decade (2).
Tuberculosis was not a very common AIDS-indicative disease (Table 4).

Table 4. HIV infection and tuberculosis in the Nordic and Baltic countries, 2006 (2)

Country / Страна

Percentage of all tuberculosis cases that were HIV positive / Доля всех случаев туберкулеза у ВИЧ-положительных в %

AIDS cases with tuberculosis as AIDS-indicative disease in percentage of all tuberculosis cases / Случаи туберкулеза со СПИДом , где туберкулез является заболеванием, указывающим на СПИД, в % от всех случаев туберкулёза

Estonia / Эстония

9.0

3.1

Latvia/ Латвия

3.4

1.4

Lithuania / Литва

0.5

0.6

Denmark / Дания

2.9

2.7

Finland / Финляндия

2.0

2.7

Iceland / Исландия

15.4

7.7

Norway / Норвегия

Not available/ нет данных

Not available/ нет данных

Sweden / Швеция

Not available/ нет данных

3.4

Treatment outcome
All the Nordic and Baltic countries reported monitoring data on treatment outcome for established pulmonary tuberculosis cases in 2005. Overall treatment success was 84% in Denmark, 69% in Sweden, 89% in Norway, 100% in Iceland, 65% in Estonia, 71% in Latvia, and 61% in Lithuania.
In Denmark, 84% of previously untreated tuberculosis cases had a successful outcome; 7% died; 0 failed and 6% were lost to follow-up. The corresponding figures for Sweden were 70%, 8%, 0 and 20%; for Norway 90%, 3%, 0 and 6%; for Iceland the success rate was 100%; the figures for Estonia were 73%, 7%, 0 and 10%; for Latvia 76%, 7%, 1% and 6%; and for Lithuania 73.5%, 9%, 2% and 10% (2).
In Denmark 93% of previously treated tuberculosis cases had a successful outcome, 7% died, 0 failed and 0 were lost to follow-up; the corresponding figures for Sweden were 64%, 0, 0 and 36%; for Norway 80%, 20%, 0 and 0; for Estonia 30%, 4%, 6% and 31%; for Latvia 50%, 10%, 1% and 10%; and for Lithuania 28%, 26%, 4% and 23% (2).
In all countries in the two regions that reported case-based data, the treatment success rate was higher for local population than for immigrants. Cases of pulmonary tuberculosis had a lower treatment success rate and higher mortality than extra-pulmonary cases, which indicates the more serious nature of pulmonary tuberculosis.

Deaths from tuberculosis
Figures for mortality by disease localization were available for 2004–2005. Most deaths were from respiratory or miliary disease. The percentages of respiratory and miliary tuberculosis deaths in Denmark were respectively 78% and 4% (2001); in Finland 82% and 5%; in Sweden 81% and 6%; in Norway 86% and 14%; in Estonia 90% and 8%; in Latvia 98% and 1%, and in Lithuania 72% and 27%.
Mortality per 100 000 population was 0.72 in Finland (2005); 0.18 in Sweden (2004); 0.15 in Norway (2004); 3.64 in Estonia (2005); 7.39 in Latvia (2005); and 8.97 in Lithuania (2005). Mortality decreased in 2000-2005 from 7.74 to 3.64 in Estonia, from 12.14 to 7.39 in Latvia, and from 10.32 to 8.97 in Lithuania (2).

Discussion
The socioeconomic crisis and the deterioration in health-care infrastructure in the Baltic countries during the 1990s contributed to the increase in tuberculosis notification rates and the persistently low treatment success rates, with increasing prevalence of multi-drug-resistant tuberculosis (MDR-TB) and HIV-related tuberculosis.
In spite of the recent introduction of high-quality diagnostic and treatment services with the expansion of DOTS and the implementation of WHO Stop TB Strategy, the national tuberculosis control programmes in the Baltic countries are still not sufficiently effective. This may be due to factors such as lack of political will, insufficient or lack of integration of tuberculosis control programmes in national health and primary health-care systems, poor services in penitentiary systems and poor follow-up treatment of released persons, the emergence of drug-resistant tuberculosis, increasing levels of HIV infection, insufficient engagement among health care providers and public health professionals, and insufficient involvement of civil society (5).
There is a great need for comprehensive monitoring of treatment outcomes, but this requires follow-up to be extended beyond 12 months and careful monitoring to detect early recurrence (6). National tuberculosis control programmes should include targeted surveillance and outreach strategies for at-risk sub-populations such as prisoners, injecting drug users and socially disadvantaged persons.
Despite some progress in curbing the tuberculosis epidemic in the Baltic countries, the epidemiological patterns differ considerably between the Nordic and Baltic regions. The tuberculosis epidemic in the Baltic countries is one of the reasons why the disease continues to be a public health threat in the EU (7). To address the problem the European Centre for Disease Prevention and Control has developed a Framework Action Plan to Fight Tuberculosis in the European Union, which covers the measures that need to be taken to control tuberculosis effectively and to eliminate the disease (defined as less than one case per million of the population) in the EU (8).

References

  1. EuroHIV. HIV/AIDS Surveillance in Europe. End-year report 2006. Saint-Maurice, France: Institut de Veille Sanitaire, 2007.
  2. EuroTB and the National Coordinators for Tuberculosis Surveillance in the WHO European Region. Surveillance of Tuberculosis in Europe – EuroTB. Report of tuberculosis cases notified in 2006. Saint-Maurice, France: Institut de Veille Sanitaire, March 2008.
  3. WHO Report 2008. Global Tuberculosis Control. Geneva: WHO, 2008.
  4. WHO Plan to Stop TB in 18 High-priority Countries in the WHO European Region, 2007-2015. Copenhagen: WHO, 2007.
  5. WHO European Ministerial Forum: “All Against Tuberculosis”. Berlin Declaration on Tuberculosis. Copenhagen: WHO, 2008.
  6. Cox H., Morrow M., Deutschmann P. Long-term efficacy of DOTS regimes for tuberculosis: systematic review. BMJ 2008; 336: 484-7.
  7. Falzon D, Kudjawu Y, Decenclos J-C et al. Stopping TB in Europe: some progress but still not there. Euro Surveill 2008; 13 (12).
  8. European Centre for Disease Prevention and Control. A Framework Action Plan to Fight Tuberculosis in EU. Stockholm: ECDC, 2008.

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