The Ship Captain’s Medical Guide – Chapter 5 – Causes and Prevention of Disease

This chapter deals with common-sense measures and some necessary precautions which should be taken to preserve the health of those aboard ship and to prevent the spread of disease where it has occurred. Of the many causes of disease, infection by living organisms is the commonest and an understanding of their mode of spread is necessary if healthy living and working conditions are to be maintained. Microbes (germs) can be classified in broad terms as viruses, bacteria, and fungi. They are widely disseminated throughout nature and although most of them are not harmful to mankind certain organisms may invade the body and produce particular diseases. They gain entry to the body, usually through the nose or mouth or the broken skin. Infection can take place directly from person to person or it may be conveyed indirectly in air, water or food or by a parasite carrier (such as an insect).