Retraction of: Scientific Reports https://doi.org/10.1038/s41598-019-45611-3, published online 24 June 2019

Editors have retracted this Article.

After publication of this paper concerns about ethical oversight of this study were brought to the attention of the Editors. The Authors were not able to provide documentation of appropriate approval from an ethics committee in either Niger or Senegal, where the participants in this study were based.

Thi-Phuong-Thao Pham, Cheikh Sokhna, Frank Wieringa, Mathieu Million, and Didier Raoult disagree with this retraction. Maryam Tidjani Alou, Dipankar Bachar, Anthony Levasseur, Souleymane Brah, and Daouda Alhousseini did not respond to correspondence from the Editors about this retraction. The Editors were not able to confirm current contact details for Aldiouma Diallo.