Prevalence and intensity of Onchocerca volvulus infection and efficacy of ivermectin in endemic communities in Ghana: a two-phase epidemiological study

@article{OseiAtweneboana2007PrevalenceAI,
  title={Prevalence and intensity of Onchocerca volvulus infection and efficacy of ivermectin in endemic communities in Ghana: a two-phase epidemiological study},
  author={M. Osei-Atweneboana and J. Eng and D. Boakye and J. Gyapong and R. Prichard},
  journal={The Lancet},
  year={2007},
  volume={369},
  pages={2021-2029}
}
BACKGROUND Ivermectin has been used for onchocerciasis control since 1987. Because of the long-term use of this drug and the development of resistance in other nematodes, we have assessed Onchocerca volvulus burdens, effectiveness of ivermectin as a microfilaricide, and its effect on adult female worm reproduction. METHODS For the first phase of the study, 2501 individuals in Ghana, from 19 endemic communities who had received six to 18 annual rounds of ivermectin and one ivermectin naive… Expand

Paper Mentions

Dynamics of Onchocerca volvulus Microfilarial Densities after Ivermectin Treatment in an Ivermectin-naïve and a Multiply Treated Population from Cameroon
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Observations do not support the operation of a strong cumulative effect of repeated treatments on the fecundity of female worms as previously described and may indicate that the worms from the multi-treated area recover mf productivity earlier but would be less productive than theworms from the ivermectin-naïve area between 80 and 180 days after iver mectin. Expand
Rates of microfilarial production by Onchocerca volvulus are not cumulatively reduced by multiple ivermectin treatments
TLDR
The data and analyses do not support the hypothesis of a cumulative effect of multiple ivermectin treatments on microfilarial production by female worms and use a Bayesian approach and Markov chain Monte Carlo techniques to fit the model to the data. Expand
Reproductive Status of Onchocerca volvulus after Ivermectin Treatment in an Ivermectin-Naïve and a Frequently Treated Population from Cameroon
TLDR
IVM still had an embryostatic effect on O. volvulus, but the effect was reduced in the frequently treated cohort compared with the control population, which may indicate a reduced sequestration of mf in the worms from the frequentlytreated group. Expand
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The level of reduction of microfilarial loads suggests that ivermectin is effective against the recrudescent population of O. volvulus in Cascades Region of Burkina Faso. Expand
Individual host factors associated with Onchocerca volvulus microfilarial densities 15, 80 and 180 days after a first dose of ivermectin.
TLDR
This study demonstrates that O. volvulus microfilarial density measured after a first treatment with ivermectin varies according to several host factors, and thus probably the rate of skin repopulation bymicrofilariae (mf) varies according-to-several host factors. Expand
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THE IMPACT OF IVERMECTIN MASS TREATMENT ON THE PREVALENCE OF ONCHOCERCIASIS BY RAPID EPIDEMIOLOGICAL ASSESSMENT IN GALADIMAWA, KADUNA STATE, NIGERIA
TLDR
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Despite repeated ivermectin treatment, evidence of O. volvulus transmission was documented in all seven villages and above the WHO threshold in two, and Vector species influences transmission through biting and parous rates and vector competence, and should be included in transmission models. Expand
Transmission of Onchocerca volvulus continues in Nyagak-Bondo focus of northwestern Uganda after 18 years of a single dose of annual treatment with ivermectin.
TLDR
To determine whether annual ivermectin treatment in the Nyagak-Bondo onchocerciasis focus could safely be withdrawn, baseline skin snip microfilariae and nodule prevalence data from six communities were compared with data collected in the 2011 follow-up. Expand
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TLDR
Biannual CDTi is recommended to continue in Asosa and its surroundings until the infection transmission is fully interrupted, and thorough entomological and serological data need to be generated to ascertain whether complete interruption of parasite transmission has been attained, and for considerations of an evidence-based CDTi cessation. Expand
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