Introduction to pathogen inactivation

This blog on the inactivation of pathogens will be structured to discuss a range of treatments and processes which may be used to inactivation micro-organisms, especially pathogens of humans and animals. There is a substantial body of data on the effectiveness of a range of treatments to inactivate bacteria of food spoilage and food safety concern so the focus of this report will initially be on the inactivation of viruses. This report will also initially focus on pathogens of animal pathogens and on thermal processing and irradiation treatments as these are my areas of interest and expertise however I will eventually extend into other fields such as novel processes (e.g. high hydrostatic pressure), extrusion and chemical/disinfection treatments.

To appreciate the effectiveness of various treatments on specific pathogens, including to accurately interpret the significance of inactivation data, it is important to have a good understanding risk mitigation sought by the treatment. And for this, you need an understanding of titres, infective dose, log reductions, safety assurance levels, likelihoods and other magic.

Inactivation data is often limited or even not available for many pathogens of concern and it may be necessary to extrapolate from known data range to evaluate the equivalence of various treatments and processes.

Risk mitigation sought

Prevent food spoilage: Measures on handling, preparation, processing and storage of food to reduce spoilage organisms present to a required level to meet a predetermined shelf life. A level of food spoilage organisms may be tolerated in a product as long as they do not lead to significant illness.

Food Safety: Measures on handling, preparation, processing and storage of food to prevent food-borne illness. A food-borne pathogen in contaminated food causes illness and even death in those that consume the product. However, the illness does not usually spread beyond those that consume it.

Quarantine safety: Measures on humans, animals or plants and their products to prevent the introduction or spread of disease. A quarantine pathogen in a contaminated product typically has a lower likelihood of causing a disease, but if it does, potential for the disease to spread and establish.

Sterility: Generally refers to the total absence of contaminating micro-organisms and is typically used in relation to therapeutics, medical devices, etc.

This post confirms my ownership of the site and that this site adheres to Google AdSense program policies and Terms and Conditions: ca-pub-0785774564823838

Next lesson: Concept of risk

I've had an interest in pathogen inactivation and have reviewed inactivation studies on viruses and collected and analysed data from such studies for over 20 years. During this time I've worked in the fields of quarantine and risk analysis where I've used this data almost on a daily basis.