TY - JOUR
T1 - Conventional parasitology and DNA-based diagnostic methods for onchocerciasis elimination programmes
AU - Lloyd, Melanie M.
AU - Gilbert, Rebecca
AU - Taha, Nathalie Tebao
AU - Weil, Gary J.
AU - Meite, Aboulaye
AU - Kouakou, Ilunga M.M.
AU - Fischer, Peter U.
PY - 2015/6/1
Y1 - 2015/6/1
N2 - Commonly used methods for diagnosing Onchocerca volvulus infections (microscopic detection of microfilariae in skin snips and nodule palpation) are insensitive. Improved methods are needed for monitoring and evaluation of onchocerciasis elimination programmes and for clinical diagnosis of individual patients. A sensitive probe-based qPCR assay was developed for detecting O. volvulus DNA, and this was tested with samples collected from an endemic area in eastern CÔte d'Ivoire. The new test was evaluated with dried skin snip pairs from 369 subjects and compared to routine skin snip microscopy and nodule palpation results from the same individuals. Onchocerciasis prevalence for these samples by qPCR, skin snip microscopy, and nodule palpation were 56.9%, 26.0%, and 37.9%, respectively. Furthermore, the combination of all three tests produced an infection prevalence of 72.9%, which was significantly higher than 53.1% detected by microscopy plus nodule palpation without qPCR. However, the qPCR assay was negative for 54 of 229 individuals with palpable nodules. qPCR could be a useful tool for detecting residual O. volvulus infections in human populations as prevalence decreases in areas following community-directed treatment with ivermectin.
AB - Commonly used methods for diagnosing Onchocerca volvulus infections (microscopic detection of microfilariae in skin snips and nodule palpation) are insensitive. Improved methods are needed for monitoring and evaluation of onchocerciasis elimination programmes and for clinical diagnosis of individual patients. A sensitive probe-based qPCR assay was developed for detecting O. volvulus DNA, and this was tested with samples collected from an endemic area in eastern CÔte d'Ivoire. The new test was evaluated with dried skin snip pairs from 369 subjects and compared to routine skin snip microscopy and nodule palpation results from the same individuals. Onchocerciasis prevalence for these samples by qPCR, skin snip microscopy, and nodule palpation were 56.9%, 26.0%, and 37.9%, respectively. Furthermore, the combination of all three tests produced an infection prevalence of 72.9%, which was significantly higher than 53.1% detected by microscopy plus nodule palpation without qPCR. However, the qPCR assay was negative for 54 of 229 individuals with palpable nodules. qPCR could be a useful tool for detecting residual O. volvulus infections in human populations as prevalence decreases in areas following community-directed treatment with ivermectin.
KW - Diagnosis
KW - Molecular diagnostics
KW - Onchocerciasis
KW - QPCR
UR - http://www.scopus.com/inward/record.url?scp=84926338524&partnerID=8YFLogxK
U2 - 10.1016/j.actatropica.2015.03.019
DO - 10.1016/j.actatropica.2015.03.019
M3 - Article
C2 - 25818324
AN - SCOPUS:84926338524
VL - 146
SP - 114
EP - 118
JO - Acta Tropica
JF - Acta Tropica
SN - 0001-706X
ER -