Molecular Detection of Tick-Borne Bacterial Pathogens in Patients With Undifferentiated Febrile Illness in India Using a Flow Chip Assay

Background: Tick-borne diseases (TBDs) play a crucial role in human morbidity and mortality, as ticks are highly effective in spreading diseases by transmitting harmful pathogens to humans and animals. The last few decades have seen an increase in the number of recognized tick-borne pathogens and the incidence of TBD worldwide. Several of these diseases are ubiquitous in India. However, in India, there is limited information on the molecular detection of tick-borne pathogens in patients with undifferentiated febrile illness. The study aims to investigate tick-borne pathogens among undifferentiated febrile patients in India using a multiplex polymerase chain reaction (PCR)-based assay.

Methods: A total of 120 blood samples were collected from patients with undifferentiated febrile illnesses of all ages. The samples were tested for a panel of (seven) tick-borne pathogens (Anaplasma, Ehrlichia, Borrelia, Bartonella, Coxiella, Rickettsia, and Francisella) using a multiplex PCR tick-borne bacterial flow chip (TBFC) assay through a semi-automated HybriSpot platform (Vitro Master Diagnóstica, Granada, Spain).

Results: Among the 120 samples tested, one was positive for spotted fever Rickettsia, two were positive for typhus group Rickettsia, one was positive for Borrelia, and two showed coinfections with Borrelia and Anaplasma.

Conclusion: Our knowledge of TBD is steadily advancing with the discovery of novel pathogens and the development of cutting-edge diagnostic tools. Although traditional diagnostic methods like serology and microscopy will remain essential for the diagnosis of TBD, the implementation of advanced molecular diagnostics such as TBFC will enhance our understanding of these diseases by enabling the identification of emerging pathogens and offering more precise and timely diagnoses.