LONDON — London is famed for its historic sites, its double-decker buses, and its West End shows, but the city now has a more dubious distinction: Britain’s public health agency says it has become the tuberculosis capital of Western Europe.
In response, health officials are taking to the streets in an effort to stop the spread of the infectious lung disease. A high-tech white van equipped with an X-ray machine is driving around London offering free checkups.
Similar vans were once common in Europe and the United States in the 1950s but most disappeared about two decades later when TB rates dropped. But in recent years, the disease has surged in the United Kingdom.
Last year, London had about 3,500 TB cases — more than the Netherlands, Belgium, Greece, and Norway combined. It also had more TB than some African countries, including Eritrea and Gambia.
Britain as a whole however still pales against India, China, and South Africa, which all have hundreds of thousands of TB cases.
‘‘We kind of took our eye off the ball and now TB has become a big problem again,’’ said Dr. Alistair Story, who runs the mobile TB van for University College London Hospitals.
He said the vast majority of TB in the UK is among the homeless, drug users, and prisoners because they live in cramped conditions that make them susceptible to infections. Despite the belief that TB is being imported into the UK by recent immigrants, Story said their rates of infection are low.
‘‘It’s certainly not the case that we could have closed the borders and avoided the problem,’’ he said, pointing out that other European countries with high levels of immigration, including France and Germany, have not had similar spikes of TB.
Tuberculosis is a highly infectious bacterial disease often spread by coughing or sneezing that kills more than 1 million people worldwide every year. It most often attacks the lungs and is highly treatable. More than 95 percent of TB deaths occur in developing countries. Experts are increasingly concerned about the rise of drug-resistant strains of TB, which require more toxic drugs to treat.
According to a global TB report issued last week by the World Health Organization, 3 million people worldwide with TB are currently going undiagnosed. Another 16,000 people with drug-resistant strains are failing to get treatment.
London’s $743,300 TB van has an X-ray machine whose scans can be instantly read by a radiographer. On average, the van picks up about one new TB case per week and screens about 10,000 people a year. If an X-ray looks worrying, staffers call a hospital to arrange confirmatory tests. The entire process of getting an X-ray and its results takes about 90 seconds.
On a recent morning, a steady flow of patients streamed into the van after getting a ticket for a free X-ray from a nearby homeless shelter. To persuade homeless people to get tested, the van relies on former TB patients including Horace Reid, 58, who got tested in 2009 after running out of breath trying to catch a bus.
Danny Hastie, 20, got sick numerous times last year but didn’t bother seeing a doctor.
‘‘I heard about this van and thought I would give it a go,’’ he said. ‘‘It’s [scary] at first because you’re thinking, ‘Oh, I might have a chest infection,’ but when they say that you’re clear, it puts your mind at rest.’’