2. Order: Ascaridida › Family: Toxocarida › Genus: Toxocara › Species: T. canis  Geography: Worldwide

3.  Both males and females have three prominent lips  Each lip has a dentigerous (teeth bearing) ridge  Eggs are 75-90 micrometers  embryonated when laid  Have pits  Very resistant to various weather and chemical conditions  Males: › 4-6 cm long  Females: › 6.5 cm long › can be as long as 15 cm › The vulva is about one-third the body length › The uteri can contain up to 27 million eggs at a time.

4.  Toxocara egg  Larvated eggs

5.  Larvae

6.  Adults

7.  Humans become infected by ingesting infective eggs, often due to close contact with puppies or from egg infected with soil  Transuterine transmission › puppy can get from mother during pregnancy or from mother’s milk.

8.  Definitive host: Dog or other canid  Paratenic hosts: mice, rabbits, and monkeys  Accidental host: Humans

9.  Toxocara cati › Very similar to Toxocara canis › One of the most common feline helminths

10.  Toxocara canis causes toxocariasis: a zoonotic infection caused by the parasitic roundworms found in the intestine of dogs.

11. 1) Ocular larva migrans (OLM):  Toxocara infections can cause an eye disease which can cause blindness.  OLM occurs when a microscopic worm enters the eye  Each year more than 700 people infected with Toxocara experience permanent partial loss of vision.  OLM occurs when larvae enter the eye. This results in a loss of vision or severe ocular inflammation http://www.youtube.com/watch?v=-8K9R2M-LfE

12. 2) Visceral larva migrans (VLM):  Repeated Toxocara infections can cause a disease that causes swelling of the body’s organs or central nervous system.  When the larval parasite migrates through the human body it is known as larval migrans.  In the UK alone there are over 300 cases of toxocariasis diagnosed each year.

13.  Symptoms : › VLM: include abdominal pain, fever, coughing, wheezing and asthma › OLM: include ophthalmologic lesions › Often found in children aged between 2 & 7 › Can also be asymptomatic

15.  Is usually made by serology or the finding of larvae in biopsy or autopsy specimens.  ELISA – › positive in 78% of those with visceral larva migrans › positive in 45% of those with ocular toxocariasi

16.  Cross-section of Toxocara Larvae in liver tissue

17.  Prednisone  Albendazole or Mebendazole

18.  Don’t allow dogs to lick your face  Wash hands after playing with pets  Avoid infected areas  De-worm dogs

19.  Small children are susceptible  Prelevant because every puppy is assumed to have this helminth

20.  http://course1.winona.edu/kbates/ascarids.htm http://course1.winona.edu/kbates/ascarids.htm  http://www.soton.ac.uk/~ceb/Students/Toxocara.htm http://www.soton.ac.uk/~ceb/Students/Toxocara.htm  http://www.dpd.cdc.gov/dpdx/html/Toxocariasis.htm http://www.dpd.cdc.gov/dpdx/html/Toxocariasis.htm  http://animaldiversity.ummz.umich.edu/site/accounts/i nformation/Toxocara_canis.html http://animaldiversity.ummz.umich.edu/site/accounts/i nformation/Toxocara_canis.html  http://www.merckvetmanual.com/mvm/index.jsp?cfil e=htm/bc/23505.htm http://www.merckvetmanual.com/mvm/index.jsp?cfil e=htm/bc/23505.htm  http://www.scielo.cl/scielo.php?pid=S0717- 77122008000100012&script=sci_arttext http://www.scielo.cl/scielo.php?pid=S0717- 77122008000100012&script=sci_arttext