Tuberculosis and social exclusion

Editor—Story et al write that developed countries need new strategies for controlling tuberculosis.¹ However, the old strategies for controlling tuberculosis may well work if they are enforced as intended.

In Norway all new arrivals are to be screened for tuberculosis, but this is only achieved among asylum seekers arriving at reception centres. In 2005, 40 100 people immigrated into Norway; only 19 were diagnosed with tuberculosis on arrival.

Among 290 cases of tuberculosis notified in Norway during 2005, 214 were confirmed by culture, and all these isolates were analysed by DNA fingerprinting (IS6110 RFLP). The DNA patterns were compared with those of all strains isolated in Norway since 1994. A total of 175 strains had not been identified previously, whereas 39 carried a pattern observed among strains of 25 different outbreaks. These imported strains originated mainly from Somalia, Ethiopia, Vietnam, and the Philippines.

The genetic diversity of the Mycobacterium tuberculosis population in Norway has increased steadily since 1994, indicating an increased import of new strains. A total of 130 transmission chains have been identified, but only 13 of these include more than five individuals. Of the 13 strains, 10 were imported from other countries, and all have been ongoing for more than five years.

In Norway, as in other countries with a low incidence, tuberculosis has increasingly come to be a disease of specific subgroups of the population. This trend provides an opportunity for focused intervention but depends on correctly identifying the population groups at risk and their cooperation. In Norway, tuberculosis is not related to homelessness, HIV, drug use, or alcohol misuse.

Elimination of tuberculosis requires better efforts to prevent and control the disease among specific groups of immigrants and greater efforts to control it in countries from which these immigrants originate.