The epidemiology of imported malaria in New Zealand 1980-92.

AIM

To describe the epidemiology of imported malaria in New Zealand for the years 1980-92.

METHODS

Malaria cases were identified from notification data and hospital discharge data. Records were matched using the discharge date, area health board, age, sex and ethnicity of the case, producing an electronic database, which was analysed.

RESULTS

During 1980-92, a total of 867 cases of malaria were identified, an average of 67 per year. Only 43% of hospitalised cases were notified. There was a predominance of male cases (69.9%) and of cases aged 20-39 (60.2%). Over 60% of cases were European. Three cases (0.3%) were fatal. The leading source regions were Papua New Guinea, Solomon Islands and Vanuatu. South East Asia, South Asia (India), East Asia (China) and Africa were source regions of more moderate importance. The species of malaria was recorded in 80% of cases of which Plasmodium vivax malaria was the most common (67.5% of cases), with P falciparum accounting for 22.5% of cases. While the rate of malaria among arrivals to New Zealand declined between 1980 and 1992 there was a significant rise in the incidence of P falciparum over this period.

CONCLUSIONS

The New Zealanders most at risk are essentially those travelling to high risk areas. There is a need to encourage the use of chemoprophylaxis for travellers to such regions-notably Vanuatu, Solomon Islands, and Papua New Guinea. Medical practitioners should notify all cases of malaria to support effective surveillance of this disease.