Pulmonary tuberculosis (PTB) (ILO/IMO Guidelines Appendix E A 15-16)

Impairment and Risks

• Reduced performance – debilitation and respiratory symptoms
• Complications – secondary infection, haemoptysis, infection in other parts of body
• Transmission to others on board

Rationale and justification

• Historically PTB has been a major problem from transmission of infection among ships crew. More recently, due to better accommodation standards, a low proportion of seafarer cases have arisen from strains present in other shipmates. Most infection is acquired ashore.
• Risk of transmission, mainly by droplet spread from coughing, in those with 'open TB'- where bacterium is present in sputum.
• Incidence varies widely, with generally low levels in high income countries with good nutrition and well developed health services but higher levels elsewhere. There are annually updated maps showing incidence produced by WHO (these have changed web link several times, it may be necessary to find them using the search facility on the who web site). 

  http://www.who.int/tb/country/en/ 

• Detectable using chest X-ray for established disease, skin (Mantoux) testing and by more recent immunological assay methods using blood.
• Progression untreated leads to loss of functioning lung tissue, with associated poor health from presence of chronic infection.
• Treatment is a prolonged course (several months to a year) of combined antibacterial therapy. Combinations used will depend on resistance of organism. Some medications have side effects that need supervision and compliance with the long courses that are essential to cure and to avoid resistance developing is a challenge for the individual that may mean strict supervision is required.
• Resistance is becoming more widespread.
• Can develop as a secondary infection when immunity is compromised e.g. by HIV infection or by immuno-supressive therapies

Clinical assessment and decision taking

The ILO/IMO Guidelines do not address when specific screening for PTB is indicated. At present some states have universal screening policies, others screen selectively and some have no specific provisions. The following is a practicable approach to apply in the absence of any other guidance or requirements.

Prior to screening obtain background information on:

a) national policies on case identification (including screening), contact tracing and treatment protocols in the country where the examination is performed.
b) relevant national incidence data if someone from other country is to be seen.