(1) The most important bacterial biological pollution is pathogenic bacterial pollution. Aquatic products, whether fresh water or seawater, are easily infected by bacteria such as Vibrio parahaemolyticus, Vibrio cholerae, Vibrio vulnificus, Salmonella, Listeria monocytogenes, Escherichia coli and Staphylococcus aureus or other pathogenic bacteria. Among them, pathogenic Vibrio is the main one, especially Vibrio parahaemolyticus. From the summary of historical data, bacterial pollution is a kind of pollution with the widest coverage, the greatest impact and the most problems, and this phenomenon will continue in the future.
(2) The virus only infects specific cells of specific animals. Therefore, food safety only needs to consider viruses that have pathogenic effects on human beings. If the virus does not grow and reproduce in food, it will not cause corruption. Viruses can exist in polluted water, frozen food and human intestines for more than several months. A small amount of virus can make people sick. The food-related viruses that cause human diseases mainly include hepatitis A virus, gastroenteritis (Norwalk) virus, mad cow disease virus and foot-and-mouth disease virus. These viruses mainly come from the intestines of patients, sick animals or carriers, and pollute water bodies or aquatic products after hand contact.
(3) Parasitic aquatic products parasitic infection mainly occurs in specific groups who like to eat raw or half-eaten aquatic products. Shrimp is the host of parasites, which can infect parasites harmful to human body. At present, there are nematodes, trematodes and tapeworms that are harmful to human health in aquatic products in China. Among them, Clonorchis sinensis and Paragonimus westermani in trematodes and Angiostrongylus cantonensis in nematodes are more common.