ABSTRACT
Due to the absence of audience reprots from Uganda on the Chloroquine (CQ) treatment failure of P.falciparum and Pyrimethamine sulfadoxine (PSD) combination; the need for a study to demonstrate the response for P.falciparum to these drugs was obvious. We accordingly assessed the response of P.falciparum malaria in primary school children from six sites scattered throughout Uganda during the month of July and Agust 1988. The standardised WHO in vivo and in vitro micro test methods were employed. A total of 3999 primary school children were screened from the six sites and of these 780(20) had malaria. While Arua had the highest rate of CQ sensitivity of 97.2; Kampala had the lowest rate of 60.5. R3 cases were detected at only two of the six sites namely Kampala with 1 case (2.3) and Jinja with also one case (2.9). PSD were sensitive by day 7 but 3 of the 60 cases (5) become parasitaemic by day 7. In vitro P. falcuparum isolates were significantly more sensitive to amodiaquine (AQ) at all sites with a mean EC 99 of 6.443u mol/L compared to 347.7u mol/L for CQ (p0.001). There was correlation between the in vitro sensitivities. We; therefore; recommend that CQ should continue to be the first line drug for the treatment of malaria in Uganda but may use PSD or AQ for slide confirmed P. falciparum resistant to CQ as the second line drugs. Quinine should also be readily available for malaria unrespondive to CQ. Source: Uganda Med. J. Vol. 8 no. 2+4; Sept.-Dec. 1991
Subject(s)
Malaria , SulfadoxineABSTRACT
The response of P. falciparum to chloroquine and pyrimethamine-sulfadoxine in vivo and chloroquine and amodiaquine in vitro was investigated in parasitaemic school children from six locations. Mean parasite sensitivity to chloroquine at day 7 was 74% (range 61-97) with parasite clearance rates between 2-3 days and complete defervescence in 85% of febrile children. Sensitivity declined in the four sites followed up to day 14 to 45% (range 37-53). Parasites were significantly more sensitive to pyrimethamine/sulfadoxine at 5/6 sites (100% day 7) but 5% of subjects became parasitaemic by day 14. In vitro isolates were significantly less sensitive to chloroquine than to amodiaquine with a mean 99% effective concentration of 348 mumol/L compared to 6.44 mumol/L. Clearly the role of chloroquine as the primary therapy for uncomplicated P. falciparum malaria should be reconsidered especially in the light of increasing disease severity and resurgence. Amodiaquine may be suitable alternative with pyrimethamine/sulfadoxine as second line and for more severe malaria prior to referral. The cost of alternative antimalarials and the dynamic and deteriorating pattern of resistance are powerful arguments for more objective slide diagnosis to minimise drug pressure and a regular drug sensitivity surveillance system. We believe that the latter should concentrate on measuring clinical drug efficacy in symptomatic outpatients rather than in asymptomatic children while the former needs more pragmatic and economical strategies possibly centred on seasonality and risk.
