Poster Presentation Australian Society for Microbiology Annual Scientific Meeting 2024

Analysis of the scabies associated microbiota demonstrates a shift to opportunistically pathogenic bacteria (#106)

Sara Taylor 1 , Martha Zakrzewski 1 , Charlotte Bernigaud 2 , Nuzhat Surve 3 , Pallavi Surase 3 , Deepani D Fernando 1 , Francoise Botterel 2 , Olivier Chosidow 2 , Katja Fischer 1
  1. Infection and Inflammation, QIMR Berghofer, Brisbane, Queensland, Australia
  2. Dermatology Department, Assistance Publique des Hôpitaux de Paris (AP-HP), Hôpital Henri Mondor, Université Paris-Est, Paris, Créteil, France
  3. King Edward Memorial Hospital Seth Gordhandas Sunderdas Medical College, Mumbai, India

Scabies is a neglected tropical disease with an estimated prevalence of 300 million cases globally, making it one of the most common dermatological diseases worldwide. Prevalence is especially high in tropical and disadvantaged regions where there is an established link with secondary bacterial infections. Research has demonstrated that scabies mites promote opportunistic bacterial infections, predominantly with Staphylococcus aureus and Streptococcus pyogenes. Despite this accepted correlation there is little molecular data to underpin this complex relationship between the parasite and opportunistic bacteria. Our aim is to provide the fundamental molecular evidence of how scabies infections interfere with the host microbiome to better understand the role scabies mites play in severe secondary bacterial infections and to improve treatment outcomes.  To achieve this we undertook a collaborative multi-national study that collected skin scrapings from scabies infected patients in India, France and Australia representing a diverse climate and socio-economic range. Microbial DNA was extracted from these samples and 16s full length rRNA and ITS1-4 sequencing have been performed using the PacBio sequel, which utilises single molecule real-time technology to generate long read lengths. Using an established bioinformatics pipeline, utilising DADA2 for quality control, denoising and amplicon sequence variant (ASV) identification, a total of 22,678 ASVs were identified from 751 samples. Community composition and microbial abundance was then analysed using the programing language R. Preliminary evidence demonstrates that there is an increase in opportunistically pathogenic organisms in scabies infected samples, in particular we see a significant increase in Staphylococcus aureus (P<0.05) in scabies infected lesions, and there was a significant decrease in commensal bacteria. Additionally, we found that in India and Australia there was a significant increase in Streptococcus pyogenes (P<0.05) in scabies infected lesions. This study is the first to quantify the scabies associated microbiome at the molecular level, and address how it might differ globally.