[Identification of tick-borne borreliosis cases by qPCR from rapid malaria diagnostic tests during the Grand Magal of Touba in Senegal].

INTRODUCTION

Antigen rapid diagnostic tests (RDTs) have been developed to facilitate malaria diagnosis in endemic areas. The blood samples collected for these tests can also be used to diagnose other infections.

METHODS

We performed nucleic acid extraction followed by PCR identification of dengue virus (DENV), Borrelia spp., Bartonella spp., and Coxiella burnetti on RDTs collected from different health facilities in Touba during the Grand Magal of Touba (GMT), a mass gathering known for its infectious disease risks.

RESULTS

A total of 2,381 RDTs were collected from eight healthcare facilities in the Mbacke department in 2022 and 2023 during the GMT. Thirteen cases (0.5%) of tick-borne relapsing fever borreliosis were identified by quantitative PCR (qPCR), including two cases of malaria-borreliosis co-infection. None of the samples tested positive for DENV, Bartonella spp., or C. burnetti.

CONCLUSION

Our results confirm that RDT antigens can diagnose non-malaria fevers, such as borreliosis, in some GMT participants with fever. Malaria RDTs used in the field are an easily accessible source of clinical samples for studying the epidemiology of fevers of unknown origin in GMT contexts.