What is the risk of exposure to Tuberculosis during travel?

The risk of exposure to tuberculosis in travel is very low for most types of travel.

It is more likely to be contracted during travel to specific countries under certain conditions (basic housing, healthcare settings, homeless shelters and prisons).

Tuberculosis is a bacterial infection which is spread through the air when an infected individual coughs, spits or sneezes. Exposure risk is determined by the prevalence of the organism in the population. While some countries may have high prevalence rates, it doesn’t mean the organism is spread uniformly within the population. Small enclaves may have very high rates, and this may distort the countrywide figures.

According to the World Health Organisation (WHO), one quarter of the world’s population has been exposed to TB with 5-10% symptomatic.

In 2022, there were over 10 million individuals newly diagnosed with TB and 1.3 million deaths.

Most individuals with TB live in low and low middle-income countries with 50% of cases found in just 8 countries (Bangladesh, China, India, Indonesia, Nigeria, Pakistan Philippines and South Africa). These are also some of the most densely populated countries in the world.

Overall, the highest burden of disease is in Africa and the least in South America.

The risk of exposure during travel is difficult to estimate. Exposure time (considerable for expatriate workers who are involved in healthcare), type of exposure (indoor versus outdoor) and type of travel (planes, trains, cruising, backpacking etc) are all considerations.

The risk of exposure to TB was investigated in a cohort of American Peace Corp Volunteers between 2006 and 2013. This was a very large study and compared with a similar one completed during the 1990’s. The rate of latent TB was estimated to be .95 per 1000 volunteer months of exposure and 0.02 per 1,000 months for active TB. These rates were notably less than those found in the earlier study. It is likely these findings support a lower incidence of TB globally and improving socioeconomic conditions.

The study also identified locations where the rates were significantly higher (Guatemala, Mexico, Fiji, Moldova, Sierre Leone and Ukraine).

The Peace Corps study helps us understand the true risk of exposure and probably reinforces the understanding that short term travel to low incidence areas poses little if any risk.

Expatriate workers living in high incidence locations should have a good understanding of the risk of exposure to TB. Post-placement screening is very important, particularly for those with conditions which put them more at risk for active disease.

Read our Tuberculosis FAQ and see information about TB vaccination.