ABSTRACT
The in-vivo 28 days extended test was applied for monitoring of the responses of P. falciparum and P. vivax to chloroquine in malaria patients referred to Malaria Research Laboratory in Bandar-Abbas Training and Health Research Center. The selected patients were treated with standard dose of chloroquine [25 mg/kg over 3 days]. Primaquine was also administered in a single dose [0.75 mg/kg in the third day] as gametocytocidal in falciparum and weekly [0.75 mg/kg/w for 8 weeks] as anti-relapse in vivax cases. From 76 falciparum malaria patients, 63 cases were followed up for 28 days; in 40 patients [63.5%] the parasites were resistant to chioroquine at RI and RII levels. In 13 patients that the asexual forms of P. falciparum were disappeared in their blood by the day 7 and they were not accessible more than one and two weeks, the response of the parasite was considered as either sensitive [S] or resistant at RI level [SRI]. The rate of the chioroquine-resistant cases of P. falciparum among Afghan refugees was higher [86.3%] than the rate in Iranian patients [51.2%]. Totally, there is no significantly difference of chloroquine-resistant rate and levels of P. falciparum in the studied areas in compare to the results of previous study. In 323 vivax malaria tested patients the mean of parasite clearance time [MPCT] was 2.91 days [ranged 1-5 days] and the parasite is still highly sensitive to chioroquine