Toxocariasis--an unlikely cause of Palm Island mystery disease.

After the suggestion was made that the "Palm Island mystery disease" might have been an epidemic of visceral larva migrans that was caused by the flying fox parasite, Toxocara pteropodis, work was undertaken to elucidate this nematode's life-cycle and pathogenicity. Studies of infections in various laboratory animals have shown unexpectedly variable susceptibility patterns, with mice harbouring most larvae for the longest time period. However, in all susceptible animals (which include mice, guinea-pigs and suckling rats), the larvae demonstrated marked hepatotropism. Experimental infections in monkeys demonstrated that primates are susceptible to this infection, but large doses of 20,000 infective eggs produced blood eosinophilia and focal granulomatous hepatitis without clinical disease or biochemical abnormalities in the blood. It is concluded that humans are susceptible to larval infections with this nematode, but that clinical manifestations would be unlikely to develop.

Volatile nitrites. Use and adverse effects related to the current epidemic of the acquired immune deficiency syndrome.

Early reports of the acquired immune deficiency syndrome (AIDS) in homosexual men suggested that the cause might be related to homosexual life-style practices, including use of recreational drugs. Inhalation of volatile nitrites is a possible contributing factor in AIDS because their pharmacologic properties lead to toxicity. Metabolism of N-nitroso compounds produces mutagens, teratogens, and potent carcinogens in 39 different animal species, and volatile nitrites have deleterious effects on human lymphocytes in vitro and in vivo. In relation to the current AIDS epidemic, the timing of production and sales of volatile nitrites for recreational use is the only new life-style factor that might answer the question "why AIDS now?" Prevalence of nitrite use among male homosexuals is very high, and almost every reported case of Kaposi's sarcoma during the past three years includes a history of prior nitrite use. The age of the group of patients in whom Kaposi's sarcoma and AIDS are developing is consistent with a cohort initially exposed seven to 10 years ago. Cessation of nitrite use could reduce the epidemic.

An epidemic of Kawasaki syndrome in Hawaii.

A community-wide outbreaks of Kawasaki syndrome, apparently the first in the United States, occurred in Hawaii in the first half of 1978. Twenty-seven of the 33 cases were subjected to intensive epidemiologic and microbiologic study. Patients with Kawasaki syndrome, compared to the general population, more often had Japanese ancestry, high-income status, and possibly a history of respiratory infection in the preceding month (44%). Staphylococcus aureus was not found in high frequency in the patients (15%), and viral cultures and serologic studies, immune electron microscopy, and guinea pig and primate inoculation did not reveal a causative microorganism. Febrile illnesses in guinea pigs inoculated with a skin biopsy specimen should not be further passaged.

Room humidifiers as the source of Acinetobacter infections.

Twenty-four patients contracted systemic infections with Acinetobacter calcoaceticus during a four-month period. Unheated room humidifiers at the patients' bedsides were implicated as the source of infection in six. The outbreak was terminated with the removal of the humidifers.