In short: Tuberculosis (TB) is a bacterial infection that usually affects the lungs and spreads through the air when someone with active TB coughs. Most short-term travellers are at low risk, but risk rises with long stays, close contact with local people (for example visiting family) and healthcare work in countries where TB is common. In the UK, the BCG vaccine is mainly recommended for unvaccinated children under 16 who will live with local people for more than three months in a high-incidence country, and for certain workers at high risk.

This guide, written by a Ready Health prescribing pharmacist and based on UK Health Security Agency (UKHSA) and NHS guidance, explains how TB spreads, who is at risk abroad and when BCG vaccination is advised.

What is tuberculosis?

TB is caused by the bacterium Mycobacterium tuberculosis. It most often affects the lungs (pulmonary TB) but can involve almost any part of the body, including lymph glands, bones, the spine and the brain. Only TB in the lungs or throat is usually infectious.

Not everyone who breathes in TB bacteria becomes ill. Many people's immune systems contain the infection without symptoms – this is called latent TB. Latent TB is not infectious, but it can become active later, particularly if the immune system is weakened.

How common is TB worldwide?

According to the World Health Organization's Global Tuberculosis Report 2025, around 10.7 million people fell ill with TB in 2024 and about 1.2 million died, making it the world's leading cause of death from a single infectious agent. Drug-resistant TB, which does not respond to the usual first-line antibiotics, remains a particular concern because treatment is longer and more complex.

Which countries have a high risk of TB?

UK guidance treats a country as high incidence when there are 40 or more new cases per 100,000 people each year. Many countries in these regions meet that threshold:

Sub-Saharan Africa
South and South-East Asia, including the Indian subcontinent
Parts of Eastern Europe and Central Asia
Parts of South and Central America and the Western Pacific

TravelHealthPro (NaTHNaC) country pages show the current TB status for each destination.

Who is most at risk of TB when travelling?

For most holidaymakers the risk is low, because infection usually needs prolonged, close contact with someone who has infectious TB. Your risk is higher if you:

stay for several months or longer in a high-incidence country
live with or visit friends and relatives in that country
work in healthcare, laboratories, prisons, refugee settings or shelters
have a weakened immune system, for example from HIV, some cancers, poorly controlled diabetes or immunosuppressing medicines
are a young child

What are the symptoms of TB?

Symptoms usually develop slowly, over weeks or months. Common signs of TB in the lungs include:

a cough lasting three weeks or more, sometimes with blood
fever and night sweats
unexplained weight loss and loss of appetite
tiredness and feeling generally unwell
breathlessness or chest pain

If you develop these symptoms during or after travel, see your GP and mention where you have been. TB is curable with a course of antibiotics, usually lasting at least six months, and NHS testing and treatment for TB are free.

Who should have the BCG vaccine before travel?

BCG (Bacillus Calmette-Guérin) gives good protection to young children against severe forms of TB, such as TB meningitis. Its protection in adults is less certain, which is why UK recommendations are targeted. According to the UKHSA Green Book and NaTHNaC, BCG is recommended for:

Unvaccinated children under 16 who will live or stay with local people for more than three months in a country with an annual TB incidence of 40 per 100,000 or more (or a high risk of drug-resistant TB).
Some unvaccinated adults whose work brings a high risk of exposure, such as healthcare or laboratory workers in direct contact with TB patients or samples, after a negative tuberculin skin test.

BCG is not usually recommended for people aged 16 or over unless the occupational risk is high, and reinforcing (booster) doses are not recommended.

How is BCG given?

Age	Dose	Notes
Under 12 months	0.05 ml	Single injection into the skin (intradermal), upper arm
12 months and over	0.1 ml	Tuberculin skin test needed first from age 6, and for some younger children

BCG must be given by a professional trained in intradermal injection. It usually leaves a small blister that heals to a scar over a few weeks. In the UK, BCG for eligible children and adults is generally arranged through NHS TB or immunisation services, so plan well ahead of travel.

How can I reduce my TB risk abroad?

Avoid close, prolonged contact with anyone known to have untreated TB.
Spend time in well-ventilated spaces where possible, especially in crowded settings.
If you work in healthcare abroad, follow local infection-control procedures and use appropriate respiratory protection.
After a long stay or known exposure, ask your GP or occupational health team whether TB screening is advisable on your return.

Frequently asked questions

Do I need a TB vaccine for a two-week holiday?

Usually not. Short trips carry a low risk, and UK guidance focuses BCG on children staying more than three months with local people and on certain high-risk workers.

I had BCG at school. Do I need another dose?

No. Booster doses of BCG are not recommended in the UK.

Can adults have the BCG vaccine?

Adults aged 16 and over are only offered BCG in special circumstances, mainly occupational exposure, because there is limited evidence it protects this age group.

Is latent TB infectious?

No. People with latent TB cannot pass it on, but treatment may be offered to stop it becoming active later.

Key takeaways

TB spreads through the air and usually requires prolonged close contact.
Most short-term travellers are at low risk.
BCG is mainly for unvaccinated children under 16 staying over three months in high-incidence countries, and some high-risk workers.
A cough lasting three weeks or more after travel should be checked by your GP.

Sources and further reading

Last reviewed: October 2026 by Shamir Patel, Independent Prescribing Pharmacist, Ready Health. This article is general information and does not replace advice from your own clinician.

Travelling for a long stay or visiting family abroad? Ready Health in Standish offers travel health consultations for people across Wigan, Chorley, Horwich and Bolton. We can review your itinerary, check which vaccines and precautions are appropriate and, where BCG may be needed, advise on how to access it. Book a travel health consultation or call 01257 676001.