Parasitic infections in humans can be detected through blood and stool tests.Different infections have their own diagnostic criteria.
Indications for Parasite Testing Parasitic infections are not asymptomatic; they always have some symptoms.Therefore, if you have a health problem, you will need to have your blood or stool tested for parasites.Preventive testing is not required in the absence of symptoms.Symptoms of suspected parasitic infection:
- The temperature rises to 37-37.5 degrees for a long time;
- Unexplained fatigue;
- A rash on the skin that suddenly appears and disappears;
- Indigestion - rumbling stomach, bloating, diarrhea;
- Test for anemia;
- Weight loss and normal appetite.
Only in certain cases does a person need to be tested for parasites, even if they don't have any symptoms.This is done when applying for a job or enrolling in school, getting a swimming certificate, or before surgery.In this case, referral by your general practitioner or paediatrician for the required examinations is required.
What parasitic infections can be tested for?
Any parasitic infection can be detected through various tests.have:
- Intestinal parasites - live in the intestinal lumen and shed their eggs in the feces;
- Extraintestinal - lives in various organs and does not produce eggs.
Intestinal parasites can be identified through stool analysis, and extraintestinal parasites can only be identified through blood.
Metatesticular disease
Infection caused by Opisthorchis flatworm.Humans become infected by eating river fish (dried or dried fish, that is, fish that has not been heat treated).Metatesticular disease is not spread from person to person, meaning patients are not contagious.However, patients shed parasite eggs in their feces, which find their way into the water and then into the fish.
trichinellosis
Trichinella spiralis are small worms that live in the muscles of pigs and wild animals.A person can become infected if they eat undercooked or undercooked meat.Trichinella spiralis from the intestines enter the muscles and form capsules there.It is an extraintestinal parasite that can live in muscles for decades without causing any symptoms.One person cannot infect others.
Ascariasis
Roundworms are long roundworms that live in the intestines.Human infection occurs through dirty hands.Inside the body, roundworms go through two stages of development.In the intestines, the eggs form larvae, which travel through the bloodstream to the lungs.They live here for two months, then are swallowed by the phlegm and returned to the intestines.Here, the roundworms develop into adult worms and release their eggs in the feces.If hygiene rules are not followed, patients may infect others.
Toxocariasis
Toxocara is a parasite of dogs and other canids.Toxocara eggs are found on animal fur and humans become infected through contact with them.After the eggs are swallowed in the intestines, larvae emerge from them, but the worms do not develop further.
The larvae are carried with the blood to different organs where they form capsules.Like Trichinella spiralis, they can live in tissues for years without showing symptoms.Patients are not contagious and do not release Toxocara eggs into the environment.
Hydatid disease
Echinococcus is a parasite that lives in dogs.People become infected through contact with animals.Echinococcus eggs pass into the intestines, where the larvae emerge.They are transported through the blood to organs and most often live in the liver.Here they form cysts - air bubbles with fluid in which the echinococcosis is found.One person cannot infect others or release parasite eggs into the environment.
Giardiasis
Giardia is the simplest microorganism; infection can occur by drinking unboiled water with dirty hands.Giardia parasites live in the small intestine and mainly cause giardiasis in children.If personal hygiene is not taken care of, patients can pass giardia in their feces and infect others.
Parasite test types
To identify parasites in your body, you'll need a stool or blood test.Intestinal worms and giardia can be identified by stool analysis; blood is a secondary method.Extraintestinal parasites can only be identified through the blood because they do not secrete eggs.
Blood tests for parasites are not 100% accurate.They may be false positives or false negatives.Reasons for erroneous results include physical characteristics, allergies, concomitant diseases, and the camouflage ability of the worm itself.
Some parasitic infections require ultrasound or X-rays.Therefore, if you suspect hydatid disease, a liver ultrasound is required first.If you find cysts there, donate blood to get Echinococcus antibodies.
Parasites rarely live in the kidneys.These are tropical protozoan schistosomiasis; they become infected by swimming in polluted waters in tropical countries.Radiographic detection of antibodies can be used to identify parasites in human bladders.
Fecal parasite analysis
This analysis is called fecal testing for worm eggs and protozoa.Stool testing can identify the following parasites:
- posterior testis;
- roundworms;
- wide tape;
- cattle and pork tapeworms;
- Strongyloides;
- whipworm;
- Giardia.
Fecal analysis of worms does not provide much information because the worms do not secrete eggs all the time and eggs are not found in all samples.To get accurate results, you need to donate stool at least 3 times, 3 days apart.It's best to check for warm stool.
The Parasep technique is more reliable - it's a study of feces diluted in a special liquid.This method is also known as fecal enrichment analysis.Sometimes, helminth eggs and protozoa are detected during co-procedures (detailed analysis of stool to diagnose digestive system diseases).
Modern research into Giardia uses PCR methods to detect the antigen in stool.The technology is 90-95% reliable.
Gua Sha
Only pinworms can be identified using the scratching method.These are small worms that live in the large intestine.At night, the female crawls out and lays eggs in the skin around the anus.The disease caused by pinworms is enterobiasis.
Pinworm disease mainly affects young children.Children can continuously infect themselves by scratching the skin near the anus and then putting their hands into their mouth.
Pinworm testing is done in the morning without bathing the child.Place a piece of tape on the skin around your anus.It is then glued to a glass slide.Laboratory technicians examined the glass under a microscope and discovered pinworm eggs.
blood test
General blood tests will give indirect signs when parasites are present in the body:
- Increased eosinophil count;
- ESR increases.
In the acute phase of the disease, the number of eosinophils increases sharply, exceeding 20%.During the chronic phase, there are virtually no changes in general blood tests.
Antibodies against the parasite can be detected by performing an enzyme immunoassay for the parasite in the blood.This study is applicable to the diagnosis of intestinal helminths and Giardia in the acute phase of the disease, as well as the identification of extraintestinal helminths.
Types of parasite blood tests
Blood tests for parasites are the same in adults and children.For children, this study is more informative because they are more susceptible to acute illness.In adults, chronic helminthiasis predominates, so blood tests often give erroneous results.
ELISA
For diagnosis, a parasite enzyme immunoassay is used.This is a test for helminth and protozoan antibodies in the blood.ELISA is most informative during the acute phase of disease, when antibodies are actively being produced.In the chronic stage, the worms are masked and the body stops producing antibodies against them.Therefore, ELISA gives false negative results.If a person suffers from allergies or an autoimmune disease, false antibodies will form and the ELISA result will be false positive.
Blood tests that detect parasites must be confirmed with other testing methods.
among children
Both blood and stool tests for parasites will provide information for your child.Children mainly suffer from acute parasitic diseases.Fecal examination for helminths and protozoa is informative in 90% of cases, and ELISA is informative in 70% of cases.
How and where to do a parasite blood test
You can get tested at a clinic or paid laboratory where you live.To get a referral for clinic testing, you will need to contact your general practitioner, paediatrician or infectious disease specialist.You can take the test yourself at any paid lab.But if you don't have a medical problem, you don't need to get tested.Asymptomatic parasitic infections (toxocariasis, trichinellosis) do not require treatment.Prescribe only if symptoms occur.