Angiostrongylus cantonensis in East New Britain, Papua New Guinea.

The first case of angiostrongyliasis (eosinophilic meningitis) to be diagnosed in Papua New Guinea in 1977, led to a survey of adult Melanesian residents of East New Britain province where the case occurred, to assess the level of immunological responsiveness to Angiostrongylus cantonensis. In 104 subjects tested using an indirect fluorescent antibody test, the serum antibody titres to A. cantonensis equalled or exceeded 1:16 in 50.7% and ranged from 1:32 to 1:64 in 17.3% of subjects. No individual tested showed evidence of active or recent angiostrongyliasis but in a patient suspected to have ocular angiostrongyliasis, the antibody titre of A. cantonensis was 1:128 in the single serum specimen obtained. In a programme to determine the distribution of this parasite in the natural hosts, 19 rats were trapped; one had adult A. cantonensis in its pulmonary arteries. Examination of 200 Achatina fulica snails revealed Angiostrongylus larvae in 62 (31%) and when these larvae were fed to laboratory rats, adult A. cantonensis were subsequently recovered from their pulmonary arteries.