Optimising the use of molecular tools for the diagnosis of yaws
Loading...
Date
2019-10-14
Journal Title
Journal ISSN
Volume Title
Publisher
Transactions of The Royal Society of Tropical Medicine and Hygiene
Abstract
Background: Yaws is a neglected tropical disease and results in lesions of skin, soft tissues and bones. PCR plays
an important part in surveillance.
Methods: Children suspected to have yaws were enrolled. From the largest lesion, paired swabs were collected,
one in transport medium and one as a dry swab. In children with multiple lesions we collected additional swabs
from up to four subsequent lesions. Swabs in transport medium were maintained in a cold chain while dry
swabswere stored at ambient temperature. Swabswere tested by PCR for Treponema pallidum and Haemophilus
ducreyi.
Results: Of 55 individuals, 10 (18%) had at least one positive PCR for T. pallidum and 12 (22%) had at least
one positive result for H. ducreyi. Concordance was 100% between swabs in transport medium and dry swabs.
One patient had PCR-confirmed yaws on the swab of a third lesion when both the first and second lesions were
PCR-negative.
Conclusions: Storing swabs in transport medium and transporting in a cold chain did not improve yield, however,
detection of T. pallidum is increased by swabbing additional lesions. As the target for yaws is eradication,
approaches to sample collection need revisiting to ensure cases are not missed.
Description
Research Article
Keywords
Eradication, Haemophilus ducreyi, negelcted tropical diseases, PCR, Treponema pallidum subspecies pertenue, Yaws