Study of the effect of single dose primaquine on gametocytaemia and infectivity among Amodiaquine-treated P.falciparum malaria patients

ABSTRACT

One hundred and five patients who attended Thayarwady Civil Hospital during 1987 and 1988 malaria seasons were studied. They were divided into three groups. Among 35 patients who were treated with amodiaquine alone, 23-33 per cent of the patients showed gametocytes in blood during days 14, 21 and 28 of therapy. Among those patients with gametocytes in blood, 50 to 63 percent of patients showed that they were viable by exflagellation method. Follow-up of one patient showed viable gametocytes in blood till 51st day of drug therapy. Among 45 patients treated with amodiaquine and primaquine (45 mg single dose given on day 3), 31 per cent of patients showed gametocytes on day 7, later only 0-10 per cent of patients showed gametocytes on day between 14, 21 and 28. Among the till day 4. From day 5 they were not viable. Except one patient who showed gametocytes at day 28 was proved to be R11 resistant to amodiaquine. Among 25 patients treated with amodiaquine and primaquine (45 mg single dose given on day 1 of hospital admission ) 36 per cent showed gametocytes on day 7 and 42 per cent showed gametocytes on day 28. Of these 26 per cent patients with gametocytes which appeared on day 28 was proved to be viable. It is suggested that primaquine 45 mg is effective to control infectivity of gametocytes in blood. It is also suggested that primaquine should be given on 3rd day of hospital admission to get the most beneficial effect.