Twenty Danish patients with the acquired immunodeficiency syndrome (AIDS) had been diagnosed by January 1984, 14 of them after 1982. Eighteen patients were male homosexuals, 8 of whom had visited the USA after 1979, 2 were heterosexual males with a history of sexual contacts in Central Africa, suggesting a transmission of AIDS from woman to man. AIDS has not been observed in drug abusers, hemophiliacs or transfused non-risk persons in Denmark. The clinical picture varied according to the presence of Kaposi sarcoma or the type of opportunistic infections, but was in general similar to that reported from the USA. Investigation of T-lymphocyte subsets revealed that the AIDS patients differed from controls and healthy homosexual men by having either a very low number of helper cells or a low helper/suppressor cell ratio. Functional immunological studies revealed a decreased natural killer cell activity and decreased blast transformation by mitogens. The survival two years after diagnosis was 16%.
A prospective study of acute diarrhoea was performed during 15 months 1981/1982 and included 731 patients and 240 controls. 43% had been infected abroad. A cluster of travellers with bacterial pathogens was diagnosed in July-August. The following pathogens were found: Campylobacter (18%), enterotoxigenic E. coli (6%), Salmonella spp. (5%), rotavirus (4%), Yersinia enterocolitica (3%), Giardia lamblia (3%), Shigella spp. (2%), Clostridium difficile (2%), enteroviruses (2%) and Entamoeba histolytica (less than 1%). More than 90% of the bacterial or parasitic enteropathogens were detected in the first stool sample. Only 10% of the patients needed hospital treatment and for 97% oral fluids were sufficient. The median duration of diarrhoea was 9 days. No fatal cases occurred and only 2 cases of chronic bowel disease were detected.
392 patients with amoebiasis, diagnosed at Roslagstull Hospital, Stockholm during 10 yr, are reviewed. The disease is increasing in frequency, due both to increased travelling by Swedish citizens and immigration from non-European countries. The risk for an ordinary charter tourist is, however, rather low. Two-thirds of the patients were symptomatic and one-third were regarded as asymptomatic cyst carriers. The importance of repeated examination of stool samples and examinations using different techniques, especially direct microscopy of fresh faeces, is pointed out. The latter technique is in our laboratory shown to be as efficient in cases with no diarrhoea as in those with diarrhoea, with trophozoites demonstrated in the same frequency in both groups. Sigmoidoscopy with scrapings was seldom of diagnostic value.
The clinical picture and epidemiologic characteristics of infection due to Campylobacter fetus subspecies jejuni were studied in 188 patients hospitalized in Finland during a three-year period. All but two patients had diarrhea; 90% had abdominal pain, fever, and fatigue; half had vomiting and headache; one third experienced electrolyte disturbances; and one fifth of the patients had other complications, most commonly pancreatitis (6%) and arthritis (5%). All age groups were affected, most usually those who were 0 to 9 years old and 20 to 29 years old. The incidence of domestic cases increased during the summer months. With only three exceptions (1.3%), all jejuni strains were sensitive to erythromycin. Among Finns who visited ten popular tourist countries, the incidence of hospitalized C jejuni enteritis cases varied from 0 to 63 per 100,000 travelers.
The changes in the intestinal Escherichia coli flora during travel has been studied by serological methods. A group of 74 tourists visiting Egypt and the Far East were given mecillinam or placebo in a randomized double-blind study. In all but 3 participants, 2 in the placebo group and 1 in the mecillinam group, a complete change in the E. coli flora occurred after a few days, and changes continued to occur during the 25 days of travel. The percentage of multiresistant strains rose from 8% in the pretravel samples to 50-60% in the posttravel samples. Less than 5% of the pretravel E. coli strains were resistant to mecillinam, whereas in the posttravel samples 42.9% of the E. coli strains in the mecillinam group and 19.1% in the placebo group were resistant to mecillinam. Of the 30 mecillinam resistant E. coli strains from the diarrhoeal samples only 6 showed transferable mecillinam resistance.