Eurosurveillance

ECDC

Tuberculosis Surveillance in Northern Europe and Baltic Sea Region, 2004: Urgent Need for Further Public Health Action

 Rediger
  Published: 29.12.06 Updated: 30.12.2006 10:47:22

K. Kutsar, J. Epshtein
Health Protection Inspectorate, Estonia

Tuberculosis case notification

In 2004, a total of approximately 16 000 cases of tuberculosis (TB) were notified in  Denmark, Finland, Sweden, Norway, Iceland, Estonia, Latvia, Lithuania and Poland and approximately 152 000 cases in the Russian Federation. TB incidence  was less than 10 per 100 000 population in the Nordic countries (Denmark, Finland, Sweden, Norway, Iceland), more than 20 in Poland, more than 40 in the Baltic countries Estonia, Latvia, Lithuania) and more than 100 in the Russian Federation  (table 1).

Children (0–14 years) accounted for 2.7% of the total reported cases, while 36.9% of cases were aged 15–44 years, 37.5% were aged 45–64 years and 22.8% were aged 65 years and above (table 2).

Of all patients, 92.0% were nationals (native or citizens) of the reporting country and 8.0% were of foreign origin. However, these figures varied greately according to region: the proportion of patients of foreign origin was 74% in Sweden, 79% in Norway and 62% in Denmark, whereas it was 3% in Lithuania, 7% in Latvia, 24% in Estonia and 1% in Russia. The proportion of culture-confirmed cases also differed largely between the countries: it  was 86.2% in Finland, 80.3% in Sweden, 81.5 in Norway, 75.6% in Denmark, 76.1% in Estonia, 71.8% in Latvia, 63.3% in Lithuania and 4.3% in Russian Federation. Of the total TB cases in all countries of the region, 87.7% were pulmonary and 12.3% extra-pulmonary TB cases. M. tuberculosis was identified as the cause in 93.8% of culture-positive cases, while M. bovis was isolated from two patients in Denmark (0.7%) and four patients (1.1%) in Sweden and M. africanum from one patient (0.3%) in Sweden.

Tuberculosis and HIV infection

Compliled data on HIV serostatus in the 2004 notified TB cases were available for Denmark, Iceland, Estonia, Latvia and Lithuania. In these countries, the proportion of HIV positive TB cases has mostly been stable in recent years, but increased in Estonia (from 0.1% in 2000 to 4.4% in 2004) and Latvia (from 0.7% in 2000 to 2.5% in 2004) (table 3).

TB was reported as initial AIDS-indicative disease in 21.5% of 452 AIDS cases notified in eight countries of the region (table 4).

Anti-tuberculosis drug resistance

Drug susceptibility was tested by one laboratory in Denmark and Latvia, two laboratories in Estonia and Finland, three laboratories in Norway, five in Lithuania, six in Sweden and 79  in Poland. Multidrug resistance among previously untreated TB cases was very low in the Nordic countries (0-1.4%), but high in Estonia (14.2%) and Latvia (12.5%); multidrug resistance in previously treated TB cases was low in the Nordic countries  (0-4.5%) and high in the Baltic countries (40.2%-46,3%) (table 5).

No data were available  from Poland and Russia. The same situation applied for combined drug resistance; primary and acquired drug resistance – low in the Nordic and high in the Baltic countries (tables 6, 7, 8).

Treatment outcome

Data on treatment outcome for the culture-positive pulmonary TB cases notified in 2003 were provided by the Nordic and Baltic countries. Treatment outcome was succesful  in 83%-100% of pulmonary TB cases and 86%-92% of the extra-pulmonary cases in the Nordic countries. In the Baltic countries these figures were 68%-74% and 76%-93%, respectively (table 9).

The high level of TB multidrug resistanse in the Baltic countries was influenced by the many cases requiring long-term treatment and cases of treatment failure.

Discussion

The Nordic countries have experienced a steady decrease in overall TB incidence for a number of decades. This decline has been more marked in native people and citizens. Migrants from countries with high prevalence of TB represent an ever increasing proportion of cases, and these patients also have a greater likelihood of having been infected with drug-resistance strains. The Baltic countries constitute a focus of TB in Europe, and TB control in these countries should be an European public health priority. Outcome data suggest low effectiveness of treatment programmes, particularly for retreated patients in these countries. Treatment success ratios fall short of the 85% recommended for new definite cases, probably as a result of inadequate medication in the face of multidrug resistance. HIV prevalence in TB patients is a sensitive indicator of the spread of HIV into the general population, and there is now an increasing trend in Estonia and Latvia where the spread of HIV is more recent. The contribution of AIDS to overall TB incidence is perceptible, and the estimate that of 3% of TB cases due to AIDS is a conservative. TB prevention and control in the Northern Europe and Baltic Sea region need to be targeted to high risk population groups including migrants from high incidence areas, HIV infected people, the elderly and populations in metropolitan areas, where incidence is higher than national averages and TB risk factors tend to aggregate.

References

1. Euro-TB. Surveillance of Tuberculosis in Europe. Report on tuberculosis cases notified in 2004. Insitut de Veille Sanitaire, Saint-Maurice, France; February 2006.
2. Euro-HIV. HIV/AIDS Surveillance in Europe. End-year report 2004. Institut de Veille Sanitaire, Saint-Maurice, France 2005, No 71.
3. WHO. Anti-tuberculosis Drug Resistance in the World. Third global report. Geneva, 2004. WHO/HTM/TB/2004.343


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