Prevalence of hemotropic mycoplasmas and coinfection with feline leukemia virus and feline immunodeficiency virus in cats in the Moscow region, Russia

Prevalence of Hemoplasma spp. positivity in potential feline blood donors and study of the association with selected clinical variables

BACKGROUND

Hemotropic mycoplasmas, hemoplasmas, are epi-erythrocytic parasitic bacteria that can be transmitted through blood transfusion.

OBJECTIVES

To study the prevalence of hemoplasma infection of potential feline blood donors and investigate the association between Hemoplasma spp. quantitative polymerase chain reaction (qPCR) positivity in blood units and selected variables.

ANIMALS

Seven thousand five hundred seventy-three blood units from 4121 privately-owned potential donor cats.

METHODS

Retrospective observational cross-sectional study. The Banco Sangue Animal (BSA)-Animal Blood Bank medical database was reviewed for all feline donations performed in 2022 in Portugal, Spain, and Belgium. Baseline characteristics and results of blood-borne pathogens screening tests were extracted from the medical records.

RESULTS

Two hundred twelve of 4034 Portuguese donor cats and 2 of 70 Spanish donor cats tested positive for Hemoplasma spp. qPCR in 2022 leading to an overall estimated prevalence of 5.2% (95% CI: 4.5%-5.9%) in potential blood donors. Using multivariable generalized estimation equation models, Hemoplasma spp. qPCR was more often positive among blood units issued from male cats (OR = 1.9, 95% CI: 1.4-2.6, P < .0001), units positive for FeLV (OR = 2.8, 95% CI: 1.4-5.6, P = .0023), and units collected in winter months (OR = 2.5, 95% CI: 1.7-3.6, P < .0001).

CONCLUSIONS AND CLINICAL IMPORTANCE

This study underscores the importance of Hemoplasma spp. and other relevant blood-borne pathogens screening at every donation. Implementing stringent screening protocols is crucial to mitigate the risk of hemoplasma transmission via blood transfusions, thereby safeguarding the health and welfare of cats receiving transfusions.

A case of mistaken identity: a systematic review, meta-analysis, and reinvestigation of hemotropic Mycoplasma spp. infection in Ctenocephalides felis (cat flea)

BACKGROUND

Feline-associated hemotropic Mycoplasma (hemoplasmas) are believed to be transmitted by two primary mechanisms: (1) direct transmission via fighting and (2) vector-borne transmission by the cat flea (Ctenocephalides felis). While the efficiency of transmission by C. felis appears low, most manuscripts focus on the prevalence of hemoplasmas in wild-caught fleas and report either a very low (< 3%) or a high (> 26%) prevalence. Therefore, we aimed to assess the influence of sample processing and PCR methods on C. felis hemoplasma infection prevalence.

METHODS

A systemic review of PubMed articles identified 13 manuscripts (1,531 fleas/flea pools) that met the inclusion criteria (performed PCR for >1 hemoplasma on C. felis collected from cats). Risk of bias was assessed utilizing the ROBINS-E tool. Meta-analysis performed in R of these manuscripts found that not washing samples and a common set of 16S rRNA primers first published in Jensen et al. 2001 were associated with increased hemoplasma prevalence. To evaluate the influence of washing on newly collected fleas, we assessed the hemoplasma status of 20 pools of 5 C. felis each, half of which were washed and half not washed.

RESULTS

Flea washing did not influence the detection of hemoplasma but instead amplified Spiroplasma. To assess non-specific amplification with the Jensen et al. 2001 primers, 67 C. felis samples (34% previously reported hemoplasma infected) were subject to PCR and sequencing. By this method, hemoplasma was detected in only 3% of samples. In the remaining "hemoplasma infected" fleas, PCR amplified Spiroplasma or other bacteria.

CONCLUSIONS

Therefore, we concluded that hemoplasma infection in C. felis is rare, and future flea prevalence studies should sequence all positive amplicons to validate PCR specificity. Further investigation of alternative methods of feline-associated hemoplasma transmission and the ability of C. felis to maintain hemoplasma infection is necessary.

Mycoplasmas as Host Pantropic and Specific Pathogens: Clinical Implications, Gene Transfer, Virulence Factors, and Future Perspectives

Mycoplasmas as economically important and pantropic pathogens can cause similar clinical diseases in different hosts by eluding host defense and establishing their niches despite their limited metabolic capacities. Besides, enormous undiscovered virulence has a fundamental role in the pathogenesis of pathogenic mycoplasmas. On the other hand, they are host-specific pathogens with some highly pathogenic members that can colonize a vast number of habitats. Reshuffling mycoplasmas genetic information and evolving rapidly is a way to avoid their host's immune system. However, currently, only a few control measures exist against some mycoplasmosis which are far from satisfaction. This review aimed to provide an updated insight into the state of mycoplasmas as pathogens by summarizing and analyzing the comprehensive progress, current challenge, and future perspectives of mycoplasmas. It covers clinical implications of mycoplasmas in humans and domestic and wild animals, virulence-related factors, the process of gene transfer and its crucial prospects, the current application and future perspectives of nanotechnology for diagnosing and curing mycoplasmosis, Mycoplasma vaccination, and protective immunity. Several questions remain unanswered and are recommended to pay close attention to. The findings would be helpful to develop new strategies for basic and applied research on mycoplasmas and facilitate the control of mycoplasmosis for humans and various species of animals.