The effect of short-term malaria chemoprophylaxis on the immune response of semi-immune adult volunteers.
In 17 semi-immune adult volunteers, chemoprophylaxis with 300 mg chloroquine base weekly for six months was found to be effective in suppressing malaria. However, following 3 months of chemoprophylaxis, a significant reduction of IFA titres was seen lasting up to 2 months after chloroquine withdrawal. There was resurgence of malaria in the post-intervention phase. 2 months after drug withdrawal, serum concentrations of IgG and factor B were significantly reduced. 3 months after initiation of chloroquine prophylaxis, a temporary but significant decrease of IgG and IgM serum concentrations was found with a corresponding decline in the number of B-lymphocytes and regulatory T-cells. These returned to normal at 6 months of chemoprophylaxis. Our findings suggest that short-term malaria chemoprophylaxis may significantly interfere with humoral and cell-mediated immunity in areas of intensive P. falciparum transmission.
Lege-Oguntoye
L
L
Department of Pharmacology, Ahmadu Bello University, Zaria.
Onyemelukwe
G C
GC
Maiha
B B
BB
Udezue
E O
EO
Eckerbom
S
S
D000328:Adult; D000818:Animals; D001402:B-Lymphocytes / Q000737:chemistry / Q000187:drug effects; D002738:Chloroquine / Q000276:immunology / Q000494:pharmacology / Q000627:therapeutic use*; D003165:Complement System Proteins / Q000032:analysis / Q000187:drug effects; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D007136:Immunoglobulins / Q000032:analysis / Q000187:drug effects; D008288:Malaria / Q000097:blood / Q000188:drug therapy* / Q000276:immunology; D008297:Male; D010963:Plasmodium falciparum; D013601:T-Lymphocytes / Q000737:chemistry / Q000187:drug effects
D007136:Immunoglobulins; D002738:Chloroquine; D003165:Complement System Proteins