Phylogenetic analysis
Two types of distance trees were generated after NCBI BLAST using neighbour-joining and fast minimum evolution methods. Both the trees were visualized on the iTOL server (http://itol.embl.de) for better grouping of all the sequences. . A total of 100 sequences in the NCBI database were found to be similar to the queried 16S rRNA gene. Among these, 70 sequences were having a query cover of 100% and the remaining 30 sequences were having a query cover of more than 90%. When comparing the percentage identity of a queried sequence with similar sequences in NCBI, 72 sequences were having more than 97% identity; while, only 28 were having less than 95% identity. For evolutionary analysis, the available genome sequences of Ignatzschineria were retrieved from the NCBI database and constructed phylogenetic tree employing neighbour-joining method (Fig. 3) and fast minimum evolution methods (Fig.4) with bootstrap analysis using 1,000 replicates.
Wounds infected with maggots are the commonest incidences in animals (Sinha, 2012) however, there is no evidence of occurrence ofIgnatzschineria spp. bacteraemia reported from animal clinical cases so far. Whereas there are several earlier reports of occurrence ofIgnatzschineria spp. bacteraemia from human patients with poor hygiene (Gupta et al., 2011; Baker at al., 2014; Cipolla et al., 2018). There are reported human case of Ignatzschineria spp. bacteremia wherein most of the described cases of Ignatzschineria spp. infections are associated with myiasis (Do et al., 2021; Heddema et al., 2016; Le Brun et al., 2015). Similar to the previous reports, our clinical isolate Ignatzschineria spp. was found to be Gram-negative, non-sporulating, non-haemolytic, nonmotile, rod-shaped bacteria (Nadrah et al., 2021; DiFranza et al., 2021). Although,Ignatzschineria spp. are generally difficult to be isolated and identified in routine bacteriological procedures and MALDI TOF – MS therefore, they are identified by 16S rRNA gene amplification and sequencing (Do et al., 2021; Gupta et al., 2011). Similar to previous reports of identification of Ignatzschineria spp., the isolate in our case was identified by 16S rRNA sequence analysis. It is strongly indicated by previous reports that Ignatzschineria spp. transmitted by flies are more commonly associated with human wound myiasis. Bacteria carried by maggots can spread into the bloodstream of the infested host, causing systemic infections as documented in previous case reports (Nadrah et al., 2021; Gupta et al., 2011; Snyder et a., 2020). There is a well-documented relation betweenIgnatzschineria spp. infection and maggot infestation thus, our hypothesis that the bacteraemia caused by Ignatzschineria spp. in maggot infested pig is justifiable. Moreover, the bacterium the pig became febrile only after receiving a dose of ivermectin treatment that might have caused death of larvae and systemic release of the inhabitingIgnatzschineria spp.
In conclusion, we reported the isolation of Ignatzschineria spp. probably for the first time from an animal clinical case of bacteraemia presumably, as a post complication of maggot wound in an adult White Yorkshire pig. The emergence of novel pathogens is one of the greatest challenges to global health security. The detection of this pathogen may be misdiagnosed in veterinary hospitals especially in low-resource settings, often leading to the underreporting of such emerging infections, since the diagnostic facilities are still in very primitive phase in developing countries. More information on virulence and epidemiology is needed of this emerging pathogen in order to explore its role in the lives of animals and humans. Novel pathogens continue to emerge in human, domestic animal, wildlife and plant populations landscapes, yet the population dynamics of this kind of biological invasion remain poorly understood. Hence, we must be prepared to recognize the signs, identify the threat to reduce the spread of infections and health consequences before they harm the health of animals and people throughout the world.
Acknowledgements
Authors are thankful to the Indian Council of Agriculture Research -National Institute of Biotic Stress Management, Raipur Chhattisgarh, India, for providing all the necessary facilities and support for carrying out this work.
Ethics statement
The authors confirm that the ethical policies of the journal, as noted on the journal’s author guidelines page, have been adhered to and the authors confirm that no ethical approval was required as this work was carried out with collected clinical samples for diagnosis. No animal experimentation was conducted in the present study.
Conflict of interest
The authors declare no conflict of interest.
Data availability statement
The nucleotide data that generated in the present study and support the findings of this study are available in NCBI (https://www. ncbi.nlm.nih.gov)