The spectrum of etiological factors of lower respiratory tract infections is very wide and depends on the region of the world in which the infection occurs. In Europe and North America, Legionella is the most common travel agent.
Legionellosis most often develops among participants of high-standard trips (accommodation in hotels), and most cases are diagnosed in people traveling to highly developed European countries (Spain, France, Italy) and North American countries. Outbreaks of legionellosis are also reported on cruise ships. In the European Union, the mortality rate from legionellosis ranges from 3.8% to 5.6%. The pathogen often imported from third world countries to developed countries (especially by immigrants) is Mycobacterium tuberculosis.
It is hypothesised that TB can easily spread through the air in population centres, m.in. in airplanes and airports. However, the risk of illness among travellers, especially for short-term trips, has not been clearly identified. Cases of tuberculosis are rarely reported to the geosentinel system; the incidence rate is higher among immigrants and travellers visiting friends and relatives (VFR). This is confirmed by the results of studies from France and Italy, where cases of tuberculosis are generally recorded among immigrants and VFR travelers, mainly from Africa.
It is not clear whether travelling increases the risk of contracting tuberculosis. Nevertheless, tuberculosis is an important health problem because it can be transmitted by direct contact, and patients must be treated in hospital conditions, in isolation from other patients. In addition, there is a serious risk of refractory cases. In recent years, the incidence of tuberculosis in the temperate climate zone, in the highly developed countries of western Europe, North America, Australia and Japan has decreased significantly, but the disease is still a serious health problem in developing countries.
For this reason, travellers France from developed countries travelling to countries with a high incidence of TB are considered to be at risk of contracting the disease. The risk of contracting latent TB in long-term trips has not yet been identified. Cobelens et al. they suggested that the risk of latent infections is comparable between travellers and the local population. According to Rieder, a large number of cases of latent tuberculosis detected among travellers from countries with low maturities may be due to a false positive tuberculin test result (pseudo-epidemics of latent tuberculosis infection in the military environment have been described in the world literature).
To date, the factors that increase the risk of respiratory infections among international travellers by age, gender, duration or destination have not been clearly identified. In their research, o’brien et al. they only showed that the risk of contracting pneumonia is five times higher for travellers France aged > 40 years.
When interviewing patients, the first step should be to determine whether respiratory problems are actually related to travel. The majority of patients diagnosed with a respiratory infection after returning from a trip can be classified into two categories: the first includes people with acute febrile illness with respiratory symptoms, the second category includes patients with chronic respiratory infections.