Souidi Y. auteur aut IRD Boudebouch N. auteur aut IRD Ezikouri S. auteur aut IRD Belghyti D. auteur aut IRD Trape Jean-François auteur aut IRD Sarih M. auteur aut IRD text journalArticle eng text/pdf born digital access Tick-borne relapsing fever (TBRF) is caused by Borrelia spirochetes transmitted to humans by Argasid soft ticks of the genus Ornithodoros. We investigated the presence of Ornithodoros ticks in rodent burrows in nine sites of the Gharb region of northwestern Morocco where we recently documented a high incidence of TBRF in humans. We assessed the Borrelia infection rate by nested PCR and sequencing. All sites investigated were colonized by ticks of the Ornithodoros marocanus complex and a high proportion of burrows (38.4%) were found to be infested. Borrelia infections were observed in 6.8% of the ticks tested. Two Borrelia species were identified by sequencing: B. hispanica and B. crocidurae. The discovery in northwestern Morocco of Ornithodoros ticks infected by B. crocidurae represents a 350 km range extension of this Sahelo-Saharan spirochete in North Africa. The spread of B. crocidurae may be related to the increasing aridity of northwestern Morocco in relation to climate change. specialized Borrelia hispanica Borrelia crocidurae Ornithodoros marocanus Ornithodoros sonrai tick-borne relapsing fever Morocco MAROC 052 082 021 39 2 316-320 2014 1081-1710 https://www.documentation.ird.fr/hor/fdi:010063103 10.1111/jvec.12106 1081-1710 [F B010063103] https://www.documentation.ird.fr/hor/fdi:010063103 https://www.documentation.ird.fr/intranet/publi/2015/01/010063103.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2015-02-02 2017-08-23 fdi:010063103 fre