Malaria N° 5 - Subject N° 8

TRIAL OF THE PARASIGHT®-F TEST FOR MALARIA DIAGNOSIS THE PRIMARY HEALTH CARE, ZIMBABWE
S. Mharakhurwa

SUMMARY
With the escalation of Plasmodium falciparum drug resistance and cognate increase in incidence of severe and complicated diseases cases, the reduction of morbidity and mortality through chemotherapy is a vital strategy for malaria control.
However, diagnosis poses a major drawback, and the current presumptive mainstay is decidedly unreliable especially in seasonal areas like Zimbabwe. In view of this, the Plasmodium falciparum histidine-rich proteine (HRP-II) antigen detection assay (Parasight®-F test) was tried at 10 different health centres in 3 malaria endemicity zones of Zimbabwe, as malaria diagnostic tool for the primary health care. Parasitological evaluations were conducted using the thick film as gold standard, and ease of operation and practicability to nurses were ascertained by questionnaire. The sensitivity of the test did not vary substantially by endemicity zone and was approximately 93 %. Specificity was 85 %, 72 % and 92 %, respectively in the hyperendemic, mesoendemeic and hypoendemic zone (56 %). However, negative predictive values did not change significantly, with a mean of 94 %. While the highest false positive rate was 28 %, false negative rates were generally lower, with a maximum of 9 %, encountered in the hypoendemic zone. The test had a J-index generally close to 1 in all endemic strata (mean 0.76; 95 % Cl 0.52-0.99). It was found that the Parasight®-F test could afford reduction in mistreatment for malaria by up to 81 %, especially in hypoendemic areas. Test acceptability evaluations showed that this method of malaria diagnosis was positively rated by both nurses and clinical malaria patients. It was concluded that the Parasight®-F test could play an important role in diagnosis of malaria in the primary health care, particularly in areas of low-hypoendemic malaria transmission and in all areas after the peak transmission period.