Invasiveness

Invasiveness ---------------

Invasiveness is the ability of organisms to penetrate other organisms and take over them without interaction from the host. This phenomenon is characteristic of parasites and is one of the most dangerous harmful factors. The division of all living organisms according to the level of invasiveness is the basis for the classification of parasites. Cells measuring 2 cm in size belong along with microscopic types of danger.

Conventionally, the degree of harmfulness is divided into the following categories:

Local – parasites are located within a specific organism and are not excreted. This category includes pathogens of cysticercosis in sheep, echinococcus and ascaris in humans and animals. The only routes of infection are nutritional in humans, contact-resorptive - biological. Spatial. Parasites can infect tissues and be located in certain areas of the body. Typically this group consists of intestinal and tissue worms with a fecal-oral route of spread. Infestation is part of one of the stages of the life cycle. Symptoms appear in early childhood. The causative agents are larval individuals of the broad tapeworm. Localization – liver, bile ducts, muscle tissue. Organismal - the parasite has completely taken control of the entire body and actively reproduces in it. At the same time, the spread of stages cannot be ruled out. The sexual development cycle is characteristic - when living in an intermediate host, adult organisms do not bear larvae. They are transmitted between hosts due to the release of eggs by mollusks. The causative agent is the helminth Fasciola hepat