Plasmodium falciparum malaria resistance to chloroquine in five communities in Southern Nigeria

Abstract

Chloroquine is still a first-line antimalarial drug in uncomplicated falciparum malaria. Increasing 
resistance to chloroquine has been reported in many parts of Nigeria. Clinical and parasitological 
responses and classes of resistance to chloroquine in falciparum malaria in five communities in Delta 
region, southern Nigeria were assessed. Chloroquine was administered to 218 patients with 
uncomplicated P. falciparum malaria. The levels of parasitemia, clinical response and classes of 
resistance were monitored for 7 days. High levels of therapeutic failures of chloroquine in P. falciparum 
malaria were recorded in the region. The frequencies of clinical and parasitological failure of 
chloroquine were 25.7% and 55%, respectively. These frequencies were significantly lower in children 
below 5 years than older people. R2 and R3 resistance occurred in 37.2% and 17.4% of the patients, 
respectively. The therapeutic failure of chloroquine was not gender dependent. We conclude that 
chloroquine is still effective in the treatment of uncomplicated P. falciparum malaria in some 
communities in Delta region of Nigeria. However, resistance to chloroquine is likely. These results may 
be used as an important indicator of the significant level of therapeutic failure of uncomplicated P. 
falciparum malaria to chloroquine in Nigeria.