Studies on disease prevention and control: microbial adaptive responses and survival, pathogenesis, decontamination, inactivation and predictive modelling, and sustainability

Abstract

This thesis describes research starting in 1997 on five areas of disease prevention and control, namely food safety microbiology, fundamentals of non-thermal decontamination technologies, scale up for technology demonstration and applications, alternative therapies and approaches, and sustainable innovation and frameworks. Production of safe food and medical devices is vital for society. Key factors governing the safe manufacture and treatment of these products rely upon achieving an acceptable balance between microbial destruction including pathogen destruction and the retention of desired nutritional and organoleptic properties for foods. Similarly, medical device manufactures’ ‘instructions for use (IFUs)’ demand high level disinfection or sterilisation without negatively affecting materials, functionality or biocompatibility. There are ever increasing demands for personalized or specialist foods and sophisticated devices to meet complexities of modern society including serving vulnerable groups such as the young, old and immunocompromised. Whilst there is an expanding volume of published literature on elucidating microbial adaptive responses to applied lethal stresses associated with food production and to a lesser degree medical devices, there remains a need to understand why thermal and emerging non-thermal processes work to desired efficacy and what conditions or circumstances operating at this balanced interface between microbial destruction and desired product functionality and quality may promote microbial survivors and triggers pathogenesis. This is an important concept as cellular and molecular functionality governs microbial survival and this influences the type and severity (dose) of decontamination modality to be applied. Not all problematical microorganisms are easily detected nor grow on simple agar plates such as the emergence of atypical or complicated resilient pathogens like parasites and drug-resistant fungi that require appropriate decontamination. Understanding the holistic interplay and totality of all applied and inimical stresses from established and emerging technologies that govern effective microbial lethality defines critical knowledge, which informs design thinking and effectiveness to meet required consumer/patient risk reduction and safety. Such understanding also commensurately shapes sustainability. A holistic knowledge provides valuable insights to help modern and developing societies in meeting unforeseen threats and shortcomings; as my elucidation of appropriate sterilization technologies for safe reuse of PPE arising from critical supplying chain shortages during COVID-19 pandemic along with sustainable waste management. Applying appropriate disinfection and sterilization technologies for treating beediseases in heat-sensitive pollen for pollination industry.