Microsporidia in Cats: An Emerging Zoonotic Pathogen

Brandy A. Burgess, DVM, MSc, PhD, DACVIM (LAIM), DACVPM, University of Georgia

ArticleLast Updated November 20212 min read

In the Literature

Taghipour A, Ghodsian S, Shajarizadeh M, Sharbatkhori M, Khazaei S, Mirjalali H. Global prevalence of microsporidia infection in cats: a systematic review and meta-analysis of an emerging zoonotic pathogen. Prev Vet Med. 2021;188:105278.


The Research …

Microsporidiosis is an emerging zoonotic concern, and cats may have a role in the environmental dispersion of microsporidia and the epidemiology of human microsporidiosis.

This systemic review and meta-analysis evaluated the worldwide prevalence of microsporidia infection and genetic diversity of organisms among owned and stray cats. A systematic search was conducted to identify relevant literature: 30 studies representing 34 datasets were included.

In general, prevalence estimates varied by continent and detection method used. The highest prevalence estimates were derived from microscopy-based studies (29.7%), and then serology (11%) and molecular techniques (8.2%). Among molecular-based studies (n = 23), pooled prevalence estimates were the highest in Africa, followed by the Americas, Europe, Asia, and Oceania. The most commonly identified microsporidia species were Enterocytozoon bieneusi and, from there, Encephalitozoon intestinalis and Encephalitozoon cuniculi. Prevalence estimates did not significantly differ among owned and stray cats.

This systematic review highlights the paucity of data from both industrialized and developing countries in supporting evidence-based prevention and control recommendations. The epidemiology of microsporidia should be a continued area of research worldwide.


… The Takeaways

Key pearls to put into practice:

  • Although microscopic detection is commonly used, identifying microsporidia spores using this method can be difficult, and misdiagnosis may result. Molecular-based detection methods are thus considered the standard for detection and identification of microsporidia.

  • E cuniculi is a pathogen in rabbits commonly reported in this review that has been associated with uveitis and cataracts in cats; consideration should be given to this as a differential diagnosis.

  • Cats are a potential reservoir for microsporidia infections that may pose a health risk to humans, particularly those who are immunocompromised. Clinicians should work with physicians to provide guidance to immunocompromised owners on safely sharing their households with cats.