Compulsory screening of immigrants for TB and HIV

Editor—The enormous problem of tuberculosis in many parts of the world and the emergence of drug resistant strains are important matters to consider when revising control programmes for tuberculosis. In many countries a high incidence of the disease among immigrants has led to calls for improvements in detecting and treating latent infection.

Coker questions the suggestion that screening for tuberculosis in immigrants should be compulsory.¹ He says that most active disease develops after immigration and that early diagnosis has not been shown to convey public health benefits. However, screening can also detect latent infection with Mycobacterium tuberculosis.²

In Norway in 2001 the incidence of tuberculosis was 550/100 000 in African immigrants and 1.9/100 000 in natives.³ Immigrants represent over 70% of cases of tuberculosis in Norway.³ The rate of transmission is, however, low, indicating that most immigrants with tuberculosis arrive with latent infection that could be detected by screening on arrival. Similar numbers have been shown in other countries.

Entry screening of immigrants is cost effective and results in public health benefits.²,⁴ Also, an imported drug resistant strain of M tuberculosis caused an outbreak which could have been avoided if latent infection had been detected and treated in the index case on arrival.⁵ Screening immigrants from high-burden countries for latent infection is well grounded in individual and public health interests. People with latent infection can be offered preventive treatment or close follow up.³,⁵