There are various types and subtypes of parasites.
The three main classes of parasites are protozoa, helminths, and ectoparasites, which can cause disease.
If you contract a parasite, you may live with it for years without noticing any symptoms develop.
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They sustain life by getting food from the host, sometimes at the expense of the hosts health.
Out of all the parasites that exist, only three main classes can cause disease in humans.
They are ectoparasites, helminths, and protozoa.
In some cases, these parasites can live on the body for weeks or months.
These types tend to live off a persons blood while they are attached.
These parasites can lead to human disease by acting as vectors of infectious pathogens.
For example,Lyme diseaseis abacterial infectionpassed to humans through a bite from an infected tick.
The pathogen doesnt harm the tick, but it will harm the host.
Not all helminths act parasitic, as some can survive without a host, making them free-living.
When a helminth has reached adulthood, it can produce larva and eggs.
Typically, people get protozoa through thefecal-oral transmission routeafter eating or drinking something contaminated by fecal matter containing protozoa.
Ectoparasite symptoms can include:
Helminths typically fail to cause symptoms in human hosts.
They’ll be able to help you with where to go for the proper testing.
Typically, tests are done at specific testing centers or labs nationwide.
Risks of Untreated Symptoms From Parasites
Parasitic infections can be severe if they are left untreated.
Over time, the parasites continue to damage the host.
Untreated parasitic infections are becoming more common in the United States.
Treating Parasites
Treatments are recommended for most parasites.
For other types of parasites, medical treatment is needed and often entails using antiparasitic drugs.
These include surgery and more potent drugs.
The three main parasites that cause human disease are transmitted in similar ways, with the exception of ectoparasites.
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