Taenia
species (tapeworm)
Test code:
X0061 - Ultrasensitive qualitative detection of common Taenia
species
by real time PCR
Taenia
is a genus of parasitic flatworms known as tapeworms, within the
class Cestoda, that infect the intestines of various mammals,
including humans, livestock, dogs, cats, and wild carnivores.
There are several Taenia
species that can be transmitted from animals to humans, such as
Taenia saginata (beef
tapeworm), Taenia solium
(pork tapeworm), and
Taenia asiatica (Asian tapeworm). Other
Taenia species infect
pets and wildlife. For example, dogs can acquire Taenia species
such as T. pisiformis, T.
hydatigena, T. crassiceps, and
T. serialis by eating infected prey such as rabbits or
rodents. Cats can be infected with
T. taeniaeformis by
eating infected mice or rats.
These tapeworms have segmented bodies and require both a
definitive host (where the adult worm lives) and an intermediate
host (where larval stages develop) to complete their life cycle.
When the intermediate host ingests the eggs through contaminated
food, water, or soil, the eggs hatch into oncospheres (embryos).
The oncospheres penetrate the intestinal wall and enter the
circulatory or lymphatic system and migrate to muscles, liver,
brain, or other tissues, where they develop into metacestodes or
cysticerci. A cysticercus becomes infective after several
months. The definitive host becomes infected by consuming raw or
undercooked tissue from the intermediate host, which contains
viable cysticerci. In the small intestine of the host the
cysticerci evaginate and attach to the intestinal mucosa via
their scolex, or head. The cysticerci mature into adult
tapeworms over 2-12 weeks, depending on the species. Adult worms
can survive in the intestine for years and keep producing new
proglottids to perpetuate the cycle.
Taenia
infection is sometimes asymptomatic in intermediate hosts, but
if the parasite load is heavy, tissue damage may occur. In
definitive animal hosts, such as dogs or cats, infections are
often mild, with possible irritation from passing segments or
minor digestive upset. In human infections, symptoms vary
depending on cyst location, number, and the host's immune
response. Symptoms may not appear for weeks to years. Some
infected people may remain asymptomatic, but in others,
infection of the nervous system can lead to serious symptoms.
Diagnosis of Taenia
infection is traditionally through microscopic examination of
feces and tissue, but this method has low sensitivity.
Polymerase chain reaction is increasingly used in diagnosis of
this infection and in environmental surveillance due to its high
specificity and sensitivity (Cuttell et al., 2013; Nunes et al.,
2003).
Utilities:
-
Help confirm the disease causing agent
-
Shorten the time required to confirm a clinical
diagnosis of
Taenia infection
-
Help ensure that herds are free of
Taenia
-
Early prevention of spread of
Taenia between animal species
-
Environmental monitoring for Taenia
-
Minimize human exposure to
Taenia
References:
Cuttell L, Owen H, Lew-Tabor AE, Traub RJ. Bovine
cysticercosis--development of a real-time PCR to enhance
classification of suspect cysts identified at meat inspection.
Vet Parasitol. 2013 May 1;194(1):65-9.
Nunes CM, Lima LG, Manoel CS, Pereira RN, Nakano MM, Garcia JF. Taenia
saginata: polymerase chain reaction for taeniasis diagnosis in human
fecal samples. Exp Parasitol. 2003 May-Jun;104(1-2):67-9.
Specimen requirement:
2 ml feces; or rectal swab; or 10 ml soil;
or 10 ml water, or used water filter media; or environmental swabs or swipes;
or 0.2 ml fresh, frozen or fixed tissue.
Contact Zoologix if advice is needed to determine an appropriate specimen type for a specific diagnostic application. For specimen types not listed here, please contact Zoologix to confirm specimen acceptability and shipping instructions.
For all
specimen types, if there will be a delay in shipping, or during
very warm weather, refrigerate specimens until shipped and ship
with a cold pack unless more stringent shipping requirements are
specified. Frozen specimens should be shipped so as to remain
frozen in transit. See shipping
instructions for more information.
Turnaround time:
2 business days
Methodology:
Qualitative
real time PCR
Normal range:
Nondetected
