Poster Presentation Lancefield International Symposium for Streptococci and Streptococcal Diseases 2025

Analysis of the scabies associated microbiota demonstrates a decrease in diversity and a shift to opportunistic pathogenic bacteria (#9)

Sara Taylor 1 , Martha Zakrzewski 1 , Charlotte Bernigaud 1 2 , Nuzhat Surve 1 3 , Deepani D Fernando 1 , Gouri Hule 3 , Francoise Botterel 2 , Pallavi Surase 3 , Vidya Kharkar 3 , Vince Connellan 4 , Wilkinson Mary-Louise 4 , Leslie Reid 5 , Julie Ross 5 , Helen Hanush 6 , Mohan G Karmakar 3 , Natasha Coventry 6 , Troy Darben 7 , Olivier Chosidow 2 , Katja Fischer 1
  1. Infection and Inflammation Program, QIMR Berghofer, Brisbane, QLD, Australia
  2. UPE-Université Paris-Est, Service de Dermatologie, Hôpital Henri Mondor, Cretail, Paris, France
  3. Seth G.S Medical College & KEM Hospital, Parel, Mumbai, India
  4. Wujal Wujal Primary Health Care Centre, Wujal Wujal, QLD, Australia
  5. Hope Vale Primary Health Care Centre, Hope Vale, QLD, Australia
  6. Cooktown Hospital, Cooktown, QLD, Australia
  7. Robina Skin Specialist Centre, Robina, QLD, Australia

With an estimated prevalence of ~400 million cases annually, scabies is one of the most common dermatological diseases globally, resulting in a substantial socioeconomic burden. Scabies impacts most in resource poor communities and has been designated a Neglected Tropical Disease by the World Health Organization in 2017.

Epidemiological studies have indicated a link between scabies and infections with opportunistic pathogens such as Staphylococcus aureus and Streptococcus pyogenes, however the molecular data to underpin this relationship was lacking.

We proposed that scabies mites alter healthy skin microbiota, interfere with host defences in the skin and enable opportunistic bacterial infections. Aiming to clarify at molecular level the role of scabies in the pathogenesis of bacterial infections, we explored the scabies-associated microbiota in geographically distinct locations with differing climatic and socioeconomic contexts

>750 skin scrapings from scabies patients in three countries (Australia, France, India) were collected. 16s rRNA and ITS1-4 PacBio full length sequences were analysed using the programing language R and a range of relevant patient data collected during sampling.

Our results demonstrate significant decrease in microbial diversity, decrease of several commensal skin bacteria and increase of pathogenic bacteria in scabies infected lesions, regardless of disease severity. In particular, S. pyogenes was greatly increased in samples from northern Australia and India. This may be highly relevant, as these communities experience extreme rates of rheumatic heart disease.

This research will inform effective intervention and management strategies for scabies and associated sequelae and may lead globally to policy changes.