Sporadic cases of jaundice were also recognized in the 19th century. From 1855 the disease became known as "catarrhal jaundice" as a result of a misconception about its etiology which was first suggested by Bamberger and perpetuated by the eminent pathologist Virchow. Volunteers with a history of jaundice or drug addiction were excluded. As a result of the epidemic, physicians came to realize that some healthy adults were carriers of the serum hepatitis virus and that infection could be transmitted by inoculation of blood or blood products, or by the reuse of inadequately sterilized needles and syringes. During World War I large epidemics of hepatitis occurred in the British, French, German, and Rumanian armies. Hepatitis became a problem for American forces in North Africa and the Mediterranean in the second half of 1943. During the Second World War, overcrowding, poor hygiene, and contamination of food and water with human feces was followed by massive outbreaks of enteric disease.