Throughout the history of immigration, people have raised concerns about waves of new immigrants bringing disease with them into the country. It's true that new populations have sometimes introduced illness into the population, but this argument has also been frequently used as a weapon to stir opposition to immigration.
VermontWatchdog.org, a website that describes itself as a government transparency news site, recently ran an article with the headline "More than one-third of refugees in Vermont test positive for tuberculosis." It claims that the Vermont Health Department is deliberately covering up this fact. The piece has since been picked up by conservative websites around the country.
Patsy Kelso, Vermont Health Department epidemiologist, joined Vermont Edition to explain what tuberculosis is and the number of incidences in the state population.
Tuberculosis is a disease on a list of reportable conditions, meaning "health care providers and laboratories are required by state regulation to report these conditions to the Health Department," Kelso says. "And we track them and respond to them appropriately."
But only active tuberculosis is tracked. Kelso says "there's a huge difference" between active tuberculosis and latent tuberculosis.
People with active TB, Kelso explains, "have symptoms. They are often able to spread TB to other people."
Tuberculosis is often present in an individual's lungs and when they cough they can spread the disease to others.
But latent tuberculosis is not contagious and people who have it are asymptomatic. If an individual has latent tuberculosis infection, that means at some point they were exposed to a person who had TB and contracted the bacteria but is not sick. Between 5 and 10 percent of those with latent tuberculosis infection may develop active TB later on, but Kelso says "90 to 95 percent of the time, those people will never develop TB illness."
Kelso adds that unlike active TB illness, latent TB infection is not reportable in Vermont. It's not routinely tested for in the population and there is no statistic on how many Vermonters might have it.
In terms of the claims about the number of refugees who test positive for tuberculosis in Vermont, that distinction between active and latent tuberculosis is important to keep in mind.
"It's not a concern of mine as the state epidemiologist. We will continue to see refugees with latent TB infection and we will continue to see, in rare cases, active TB illness in refugees – like we do all the time in U.S.-born Vermonters." - Patsy Kelso, Vermont Health Department epidemiologist
"Roughly a third – about 35 percent I think it is – of refugees test positive for TB, meaning they have latent TB infection," Kelso says. "And it varies a little bit. It depends on what part of the world they come from, because there's more TB in some parts of the world than in others."
But very few refugees have tested positive for active TB infection. Between 2003 and 2015, the state has recorded 77 cases of active tuberculosis in Vermont. Of those, the Health Department says just 15 were diagnosed in refugees. 26 of the cases were in U.S.-born individuals. The remainder were in people who fell into other categories, like people living in Vermont on student or work visas.
"There's a really stringent medical screening that refugees go through overseas," Kelso says, explaining that all refugees are required to get a chest X-ray before coming to the U.S. "If that chest X-ray indicates possible TB, they undergo further testing, including lab tests. If they're diagnosed with TB, they're not allowed to come here until they go through six months of treatment and further lab testing to show that they've been cured of TB. Only then are they allowed to come."
Kelso has a firm stance on the question of whether or not people should be worried about refugees putting Vermonters at risk of tuberculosis. "It's not a concern of mine as the state epidemiologist,” she states. "We will continue to see refugees with latent TB infection and we will continue to see, in rare cases, active TB illness in refugees – like we do all the time in U.S.-born Vermonters. And those people can get treated and followed up appropriately in our health care system here."
