Chloroquine-resistant Plasmodium falciparum in eastern Sudan

Area of Science:

• Medical Research
• Parasitology
• Clinical Trials

Background:

• Chloroquine has been a primary treatment for Plasmodium falciparum malaria.
• Emergence and spread of drug-resistant malaria strains pose a significant global health threat.
• Eastern Sudan is an endemic region for malaria, susceptible to drug resistance.

Purpose of the Study:

• To assess the in vivo sensitivity of Plasmodium falciparum to chloroquine in patients in Eastern Sudan.
• To correlate in vivo and in vitro testing methods for chloroquine sensitivity.
• To investigate factors contributing to the emergence and spread of chloroquine-resistant malaria.

Main Methods:

• In vivo testing of chloroquine sensitivity in 61 malaria patients with acute symptoms.
• In vitro testing using the World Health Organization microtest in 21 patients.
• Correlation analysis between parasitemia persistence, symptoms, and drug resistance levels (RI, RII, RIII).

Main Results:

• Plasmodium falciparum exhibited significant chloroquine resistance in 42% of patients (26 out of 61).
• High-grade resistance (RIII) showed a strong correlation with persistent parasitemia and symptoms.
• In vivo and in vitro testing results were highly correlated, with resistant strains growing above 0.8 X 10(-6) mol/l.
• Factors like refugee movement, drought-induced immunity loss, and heavy rainfall potentially enhance resistance spread.

Conclusions:

• Chloroquine resistance is a major issue in Eastern Sudan, necessitating alternative treatment strategies.
• The study validates the correlation between in vivo and in vitro drug sensitivity testing.
• Environmental and demographic factors contribute to the development and dissemination of resistant malaria strains.