Fikireselassie Samuel.pdf - Addis Ababa University

active than other anthelminthics against Necator americanus It is less effective against Trichuris
trichiura with CR between 10%and 77% and ERR between 61% and 99 % (WHO, 1998).
Treatment of T. trichiura with single oral doses of current anthelminthics is unsatisfactory;
hence, new anthelminthics are urgently needed (Keiser and Utzinger, 2008; Olsen et al., 2009).
In Ethiopia, the respective cure rate and egg reduction rates of 83.9% and 96.3% were reported
for Ascaris lumbricoides while the respective cure rate and egg reduction rates reported for
hookworms were 84.2% and 95.0% (Adugna et al., 2007). Benzimidazole anthelminthic drugs
in the doses used to treat soil-transmitted helminth infections have shown systemic toxic effects
such as: transient abdominal pain, diarrhea, nausea, dizziness, and headache.
The scale up of chemotherapy programs that is underway in various parts of Africa, Asia and
South America, particularly targeting school children, is likely to exert increasing drug pressure
on parasite populations, a circumstance that is likely to favor parasite genotypes that can resist
anthelminthic drugs. Given the paucity of suitable alternative anthelminthics, it is imperative that
monitoring programs are introduced to assess progress and detect any changes in therapeutic
efficacy that may arise from the selection of worms carrying genes responsible for drug
resistance.
The well documented occurrence of resistance to anthelminthics in nematode populations of
livestock (Wolstenholm et al., 2004) highlights the potential for frequent treatments used in
chemotherapy programs to select drug resistant worms. Such an eventuality threatens the success
of treatment programs in humans, both at individual and community levels (Albonico et al.,
2004). This indicates that, the possible development of anthelminthic resistance (AR) to
currently available anthelminthics is a subject of significant interest.
Albendazole causes degenerative alterations in the tegument and intestinal cells of the worm by
binding to the colchicine-sensitive site of tubulin, thus inhibiting its polymerization or assembly
into microtubules. The loss of the cytoplasmic microtubules leads to impaired uptake of glucose
by the larval and adult stages of the susceptible parasites, and depletes their glycogen stores.
Degenerative changes in the endoplasmic reticulum, the mitochondria of the germinal layer, and
the subsequent release of lysosomes result in decreased production of adenosine triphosphate
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