The number of resistant tuberculosis cases is increasing, a development that is causing concern among Danish researchers.

"With the current global trend, we maysoon be looking at more cases of multi-resistant tuberculosis in Denmark than the few cases we see today. It is a good example of the global challenge of cross-border diseases," says Christian Wejse, an associate professor at Aarhus University and medical doctor at Aarhus University Hospital.

"The incidence of resistant types of tuberculosis is high in the top ten countries from which we receive most immigrants. And in some European countries, multi-resistant tuberculosis accounts for more than 30% of the cases, for example in Eastern Europe. It is worrying because multi-resistant tuberculosis is very difficult to treat," says Christian Wejse.

Hospitalised for months 
The treatment of multi-resistant tuberculosis is both extremely intensive for the individual patient and costly for the healthcare system. The cost of treating one patient is approx. DKK 0.5 million.

Patients are treated on special isolation wards to prevent spread of the disease and with five types of antibiotics for two years, one-third of this being administered intravenously. The treatment may result in serious side-effects, such as hearing loss and mental disorders.

"Earlier detection of infected persons is crucial to controlling tuberculosis. An untreated patient can infect an average of 10-15 people, so the disease can spread quickly," says Christian Wejse.

Incidence of tuberculosis highest among immigrants
While the number of cases of the non-resistant type of tuberculosis is decreasing in most Western European countries, the exact opposite trend has been observed in Denmark in recent years. The latest figures show an increase from 380 infected persons in 2011 to 421 in 2012. A growing number of immigrants bring the disease from their home country and thus contribute to this unfortunate development.

"In Denmark, the incidence of tuberculosis is now twice as high as in Sweden and Norway, so we naturally take the situation seriously. The largest increase is seen among socially disadvantaged Danes, but overall 66% of all tuberculosis cases in 2011 were immigrants or their descendants,” says Christian Wejse.

Greenlanders constitute the largest group of infected persons with a non-Danish background. The incidence of tuberculosis in this group is now as high as that in Denmark at the end of the 19th century. But also Somalis, Indians, Afghans, Pakistanis and Filipinos feature in the statistics.

On average, 8% of the patients in Denmark die during treatment, among other things because they seek medical help too late.

About tuberculosis

• Tuberculosis is an infectious disease caused by bacteria
• The disease most frequently affects the lungs and spreads through coughing
• According to the WHO, there were almost 9 million new tuberculosis cases and 1.4 million deaths worldwide in 2011
• In Denmark, 421 cases of tuberculosis  were recorded in 2012

Further information
Christian Wejse, Associate Professor and medical doctor
Aarhus University, Department of Public Health 
Aarhus University Hospital, Department of Infectious Diseases
Tel. +45 2012 4958
wejse@dadlnet.dk