In routine health protection, high-temperature disinfection is a widely recognized and commonly used method. However, there is a false perception that high-temperature disinfection can kill all pathogens for no matter how long. It’s actually a big mistake, so let’s examine the mystery in detail today.
The principle of high-temperature disinfection is primarily to use high-temperature to degenerate the proteins of pathogens and deactivate the nucleic acid, thereby achieving extinction. In general, high-temperature disinfection is common in cooking, steam disinfection, etc. There are differences in the tolerance of different pathogens to high temperatures, but in no case does the length matter.
In the case of bacteria, for example, most bacteria will be killed after some time in boiling water at 100°C. For example, coliform, which boils in about 5 – 10 minutes, can be basically wiped out. However, there are bacterial spores, such as that of the Tetanus Bacillus, which are super-heated. The sprout shell is so dense that it protects internal biomass. Even at 100°C, it takes 1 – 3 hours or more to boil it down. If only simple treatment of objects containing tremors in sprouts in boiling water for a short period of time, the sprouts will remain alive and, once they enter suitable environments such as human wounds, they will develop and cause disease.
The behaviour of the virus varies at high temperatures. The influenza virus is relatively “vulnerable” and loses activity at temperatures around 60°C in about 30 minutes. Hepatitis B, on the other hand, is more heat-resistant, takes four hours at 60°C to become completely contagious, and around 10 minutes at 100°C to be completely eliminated. In the absence of sufficient high-temperature time during the sterilisation of medical devices contaminated with Hepatitis B virus, there is a risk that the virus remains, causing cross-infection in subsequent use.
Fungi also has different tolerances for high temperatures. Like yeast, at 60 °C – 80 °C, 15 – 30 minutes are suppressed or destroyed. But some filamental fungi spores, such as fungus, can withstand higher temperatures and may take 30 minutes to an hour in boiling water at 100°C. In the food-processing industry, if there is insufficient heat time for the treatment of raw materials that may be contaminated with fungus, residual spores may grow and reproduce in subsequent processing, storage, causing deterioration of the food and endangering human health.
In the real-life scenario, if the dishes are boiled and decontaminated in the family kitchen, they are simply taken out immediately after the water has been burned, and it may not be possible to completely eliminate some heat-resistant pathogens. Particularly in some areas where sanitation is poor, water sources can be contaminated with a variety of pathogens, and if disinfection is not complete, it is highly susceptible to health problems such as intestinal diseases. In medical institutions, high-temperature disinfection requirements, such as surgical devices, are more stringent. In the absence of sufficient time for disinfection, even a small amount of resistance or virus residues, there is a risk of serious medical source infections, causing great pain and risk to patients.
So, how do we do this right? General household articles, such as utensils, towels, etc., can be disinfected by cooking. The complete immersion of the articles in the water, which lasts 15 – 30 minutes after boiling, can effectively kill most common pathogens. For high-temperature glassware, metal appliances, etc., steam can also be sterilized, with high voltage vapour at 121°C maintained at 15 – 20 minutes, with better disinfection. In medical institutions, high-temperature sterilisation temperature and time parameters are set in strict accordance with disinfection norms, based on the different materials of medical equipment and the type of pathogens that may be contaminated, and the sterilisation equipment is periodically tested and calibrated to ensure the reliability of the sterilisation effects.
In sum, high-temperature disinfection is not simply a matter of high-temperature; time is a crucial factor. Our health and safety can only be truly effective if we properly understand the tolerance of different pathogens for high temperature and time, and if we are to be scientifically and rationally sterilised.
