Medical Care
In moderate-to-heavy Trichinella infections, the goal is to stop the larval invasion into the host muscle.
Within 1 week of ingestion of contaminated meat, administer albendazole (5 mg/kg/d for 1 wk) or mebendazole (5 mg/kg/d for 8-14 d). Note that mebendazole is no longer commercially available in the United States but can be obtained from Expert Compound Pharmacy (expertpharmacy.org).
This drug is effective against worms limited to the intestinal lumen.
The goal is to prevent systemic invasion.
Thiabendazole does not affect tissue larvae.
Surgical Care
A muscle biopsy is necessary only if the diagnosis is unclear after equivocal clinical, laboratory, or serologic testing.
Consultations
See the list below:
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Infectious disease specialist
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Cardiologist, if evidence of cardiac involvement
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Neurologist, if evidence of neurologic involvement
Diet
No diet limitations are indicated; however, this is an excellent opportunity to educate patients regarding the avoidance of potentially infected meats and how to properly cook and store foods. For further details, see Prevention.
Activity
For severe infections, bed rest is recommended. This is especially important upon evidence of myocardial involvement because patients may deteriorate clinically during ambulation.
Prevention
The following suggestions for prevention and control of trichinosis in humans have been adapted from patient education materials by the Centers for Disease Control and Prevention:
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Cook meat to safe temperatures, using a food thermometer to measure the internal temperature of the cooked meat.
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Ensure appropriate temperatures are reached for different types of meat (listed on the CDC website).
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Wash hands and other food preparation and storage equipment with warm water and soap after handling raw meat.
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Ensure proper hygiene during preparation, serving, and storage of food.
Trichinella infection in animal populations can be prevented by not allowing domesticated and wild animals to eat uncooked meat of any animals that may be infected with Trichinella.
Long-Term Monitoring
Patients need continued monitoring because clinical improvement is slow.
Transfer
Transfer to another level of care is rarely needed unless the diagnosis is in question or severe sequelae are present.
Further Inpatient Care
Inpatient care is rarely needed.
Consider trichinosis in cases of heavy infection with evidence of shock, encephalitis, myocarditis, or pneumonitis.
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Encysted larvae of Trichinella species in muscle tissue, stained with hematoxylin and eosin (H&E). The image was captured at 400X magnification. Courtesy of the US Centers for Disease Control and Prevention (http://www.dpd.cdc.gov/dpdx/HTML/Trichinellosis.htm).
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Trichinella larvae, in pressed bear meat, partially digested with pepsin. Courtesy of the US Centers for Disease Control and Prevention ((http://www.dpd.cdc.gov/dpdx/HTML/Trichinellosis.htm).
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Larvae of Trichinella from bear meat. Courtesy of the US Centers for Disease Control and Prevention (http://www.dpd.cdc.gov/dpdx/HTML/Trichinellosis.htm).
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The number of cases of trichinellosis by age. Courtesy of Centers for Disease Control and Prevention (CDC) (https://www.cdc.gov/parasites/trichinellosis/resources/trichinellosis_surveillance_summary_2015.pdf).
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Epidemiology of trichinellosis in the US. Courtesy of Centers for Disease Control and Prevention (CDC) (https://www.cdc.gov/parasites/trichinellosis/resources/trichinellosis_surveillance_summary_2015.pdf).
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Reported cases of trichinellosis 2011-2015. Courtesy of Centers for Disease Control and Prevention (CDC) (https://www.cdc.gov/parasites/trichinellosis/resources/trichinellosis_surveillance_summary_2015.pdf).
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Trichinella nurse cell. Courtesy of Dickson Despommier, PhD, and Daniel Griffin, MD, PhD, Parasitic Diseases, 6th Ed, published by Parasites Without Borders (www.parasiteswithoutborders.com).
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Life cycle of Trichinella in humans. Courtesy of Dickson Despommier, PhD, and Daniel Griffin, MD, PhD, Parasitic Diseases, 6th Ed, published by Parasites Without Borders (www.parasiteswithoutborders.com).
Tables
Species |
Distribution |
Major Hosts |
Reported from Humans |
T spiralis |
Cosmopolitan |
Domestic pigs, wild mammals |
Yes |
T britovi |
Eurasia/Africa |
Wild mammals |
Yes |
T murrelli |
North America |
Wild mammals |
Yes |
T nativa |
Arctic/subarctic, Palaearctic |
Bears, foxes |
Yes |
T nelsoni |
Equatorial Africa |
Hyenas, felids |
Yes |
T pseudospiralis * |
Cosmopolitan |
Wild mammals, birds |
Yes |
T papuae * |
Papua New Guinea, Thailand |
Pigs, crocodiles |
Yes |
T zimbabwensis * |
East and South Africa |
Crocodiles, lizards, lions |
No |
* Nonencapsulating types |
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