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.
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.
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.
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)