Introduction

International travel has become an established feature of modern life. Tourists from developed countries sunbathe on tropical beaches and trek on adventurous expeditions. Businessmen search for new trade opportunities and aid workers visit remote corners of the globe. Visitors to such tropical locations may expose themselves to unusual pathogens, including pathogens with long incubation periods whose symptoms can appear after the traveller returns home.

The wide availability of intercontinental travel has also encouraged immigrants from all parts of the world to come to developed countries, searching for political and economic security. They, in turn, may bring with them illnesses rarely if ever seen by physicians practising in temperate areas.

The purpose of this chapter is to highlight the important bacterial, parasitic and fungal infections which should be considered in the differential diagnosis of respiratory infections in the returning traveller and incoming immigrant.

Bacterial infections

Melioidosis

Melioidosis was first described in 1911 in Rangoon, Burma. The post-mortem of a 10-year-old ‘morphia’ addict who died of pneumonia showed a ‘cheesy’ consolidation of the lung and subcutaneous abscesses on the legs. Burkholderia pseudomallei (formerly Pseudomonas pseudomallei) was cultured from the lung tissue. Since this first report, melioidosis has been recognised to be highly prevalent in Southeast Asia and Northern Australia with additional sporadic cases in the Indian sub-continent, Africa, the West Indies and South and Central America.