Molecular Profiling of Ticks and Associated Pathogens: First Report of Rickettsia sibirica, Rickettsia slovaca, and Babesia microti in Ticks From Pakistan

TL;DR

This study identifies new tick-borne pathogens in Pakistan, including Rickettsia and Babesia, highlighting potential risks to human and animal health.

Contribution

First report of Rickettsia sibirica, Rickettsia slovaca, and Babesia microti in ticks from Pakistan.

Findings

Rhipicephalus microplus was the most prevalent tick species in the study area.

Coxiella burnetii was the most common tick-borne pathogen detected.

Phylogenetic analysis grouped ticks and pathogens into distinct genetic clades.

Abstract

Global distribution of ticks and their associated tick-borne pathogens (TBPs) presents substantial health concerns for both humans and animals. The present study aimed to investigate the distribution, morpho-molecular identification, and associated TBPs of diverse tick species collected from Khyber Pakhtunkhwa and Punjab provinces of Pakistan. Morphological identifed ticks were molecularly confirmed via cytochrome oxidase I (COI) and 16S rRNA genes, which showed 15 different tick species. Among them, we found the highest prevalence rate of Rhipicephalus (Rh) microplus (404/1803; 22.41%), while the lowest prevalent tick species were Haemaphysalis (Hae) montgomeryi (44/1803; 2.44%). Similarly, the highest tick load was found on cattle (544/186; 2.92), while least was found on goats (272/164; 1.66). Various TBPs, including Rickettsia (R) spp. (via gltA, sca4, ompA, ompB genes), Anaplasma (A) sp. (via 16S rRNA gene), Coxiella burnetii (via IS1111 gene), Piroplasm and Hepatozoon (H) spp. (via 18S rRNA gene) were screened. The Rh. microplus tick species showed highest positivity rate (11.63%) for various TBPs, whereas Hae. sulcata ticks were recorded as TBPs free in current study. Among the detected TBPs, Coxiella burnetii was most prevalent (1.72%), followed by A. phagocytophilum & R. slovaca (1.44% each), R. sibirica (0.78%), R. raoultii (0.61%), H. canis (0.55%), R. conorii subsp. raoultii (0.50%), Hepatozoon sp., (0.44%), Theileria (Th) uilenbergi (0.39%), Babesia (B) microti (0.33%), and Th. luwenshuni (0.28%). This study provides the first report of TBPs, including R. slovaca, R. sibirica, and B. microti, in ticks from Pakistan. Phylogenetic analysis was performed based on the aforementioned genetic markers, in which ticks and their associated TBPs formed distinct clades with their corresponding isolates. This research work provides a deep insight regarding the characterization of different ticks and their associated TBPs in Pakistan and, significantly, it presents evidence of potential zoonotic threats to both animal and public health due to these newly detected pathogens.

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