[Prophylactic effect of artesunate against experimental infection of Schistosoma mansoni].
OBJECTIVE
To study the prophylactic effect of artesunate against the infection of Schistosoma mansoni in mice and its optimal scheme for preventing schistosomiasis mansoni.


METHODS
BALB/c mice were infected by tail dipping method with S. mansoni cercariae. Mice were administered orally with artesunate at different developmental stage of the parasite, with different regimens. The reduction rates of total and female worms, the number of eggs in the liver and intestine, and the fecundity were calculated and treated statistically.


RESULTS
The optimal dosage of artesunate to prevent murine schistosomiasis was 300 mg/kg. The parasite was found to be especially susceptible to artesunate in its schistosomula stage of 14 and 21 d after infection, resulting in worm reduction rate of 84% and 93% respectively compared with control. High protection was reached with worm reduction rate of 99% by the regimens of 300 mg/kg once a week for 4 consecutive weeks beginning 14 d after infection. The fecundity was significantly suppressed, suggesting that the drug inhibited sexual maturation of female worms. The effective protection could also be gained with prolonged interval time of two weeks with worm reduction rate of 97% and 96% beginning 14 or 21 d after infection.


CONCLUSIONS
Artesunate kills schistosomula and reduces the fecundity of females effectively, the infected mice do not develop schistosomiasis mansoni when treated with artesunate. It's proposed that an optimal scheme for field use be the first administration 14 or 21 days after infection with 1 or 2 weeks interval.
Institute of Parasitic Diseases, Zhejiang Academy of Medical Sciences, Hangzhou 310013, China.
Shao-hong
SH
Lu
Xiao-lan
XL
Yan
Si-wen
SW
Li
Ling-juan
LJ
Wu
Jun-fan
JF
Shi
Xu
X
Liu
Xiao-hua
XH
Yan
Ming-jin
MJ
Yang
Lei-jun
LJ
Lou
Takashi
T
Kumagai
Li-yong
LY
Wen
Nobuo
N
Ohta
D000818:Animals; D000962:Antimalarials / Q000627:therapeutic use*; D037621:Artemisinins / Q000627:therapeutic use*; D000077332:Artesunate; D005260:Female; D051379:Mice; D008807:Mice, Inbred BALB C; D012550:Schistosoma mansoni / Q000187:drug effects*; D012555:Schistosomiasis mansoni / Q000517:prevention & control*; D012717:Sesquiterpenes / Q000627:therapeutic use*
D000962:Antimalarials; D037621:Artemisinins; D012717:Sesquiterpenes; D000077332:Artesunate