TY - JOUR

T1 - The effect of eight half-yearly single-dose treatments with DEC on Wuchereria bancrofti circulating antigenaemia.

AU - Simonsen, Paul E

AU - Magesa, Stephen M

AU - Meyrowitsch, Dan W

AU - Malecela-Lazaro, Mwele N

AU - Rwegoshora, Rwehumbiza T

AU - Jaoko, Walter G

AU - Michael, Edwin

N1 - Keywords: Administration, Oral; Adolescent; Adult; Aged; Aged, 80 and over; Animals; Antigens, Helminth; Child; Child, Preschool; Diethylcarbamazine; Drug Administration Schedule; Endemic Diseases; Female; Filariasis; Filaricides; Humans; Male; Middle Aged; Prevalence; Rural Health; Tanzania; Treatment Outcome; Wuchereria bancrofti

PY - 2005

Y1 - 2005

N2 - The effect of eight half-yearly treatment rounds with diethylcarbamazine (DEC; 6mg/kg bodyweight) on Wuchereria bancrofti-specific circulating filarial antigen (CFA), a marker of adult worm infection, was followed in 79 individuals who were CFA-positive before start of treatment. Half of these were also microfilariae (mf)-positive. Microfilaraemia decreased rapidly after onset of treatment and became undetectable after four treatments. Circulating antigenaemia also decreased progressively, but at a much slower rate. After two, four and eight treatment rounds, the mean CFA intensity was reduced by 81, 94 and 98%, and the prevalence of CFA positivity was 85, 66 and 57%, compared with pre-treatment, respectively. CFA clearance rates were negatively related to pre-treatment CFA intensities, and were higher among pre-treatment mf-negative individuals than among pre-treatment mf-positive individuals. Even among patients who had pre-treatment CFA intensities above the upper measuring level (32000antigen units), and who continued to have intensities above this level after treatment, a decrease in post-treatment CFA intensities was obvious from a continuous decrease in ELISA optical density values. Repeated DEC therapy thus appears to have a slow but profound and persistent macrofilaricidal effect, which in the long run may be beneficial to populations undergoing DEC-based control interventions by reducing the probability of future morbidity development.

AB - The effect of eight half-yearly treatment rounds with diethylcarbamazine (DEC; 6mg/kg bodyweight) on Wuchereria bancrofti-specific circulating filarial antigen (CFA), a marker of adult worm infection, was followed in 79 individuals who were CFA-positive before start of treatment. Half of these were also microfilariae (mf)-positive. Microfilaraemia decreased rapidly after onset of treatment and became undetectable after four treatments. Circulating antigenaemia also decreased progressively, but at a much slower rate. After two, four and eight treatment rounds, the mean CFA intensity was reduced by 81, 94 and 98%, and the prevalence of CFA positivity was 85, 66 and 57%, compared with pre-treatment, respectively. CFA clearance rates were negatively related to pre-treatment CFA intensities, and were higher among pre-treatment mf-negative individuals than among pre-treatment mf-positive individuals. Even among patients who had pre-treatment CFA intensities above the upper measuring level (32000antigen units), and who continued to have intensities above this level after treatment, a decrease in post-treatment CFA intensities was obvious from a continuous decrease in ELISA optical density values. Repeated DEC therapy thus appears to have a slow but profound and persistent macrofilaricidal effect, which in the long run may be beneficial to populations undergoing DEC-based control interventions by reducing the probability of future morbidity development.

U2 - 10.1016/j.trstmh.2004.11.016

DO - 10.1016/j.trstmh.2004.11.016

M3 - Journal article

C2 - 15869771

VL - 99

SP - 541

EP - 547

JO - Transactions of the Royal Society of Tropical Medicine and Hygiene

JF - Transactions of the Royal Society of Tropical Medicine and Hygiene

SN - 0035-9203

IS - 7

ER -