Changes

=Epidemiology=

=Epidemiology=

''T. canis'' is present worldwide with a wide range of prevalances in different areas from 5 - 80%. Adult animals carry the fewest worms since initial infection causes immunity which leads to the shedding of adult worms from the intestines. The largest numbers of worms are found in dogs less than 6 months old who have not yet gained immunity to the worms. The high levels of prevalence of this species worldwide is largely due to the difficulty in controlling its spread. The eggs are extremely resistant in the environment and so can persist for several years. The females lay very large numbers of eggs, up to 700 per gram of faeces, making the removal of such a large number difficult. This final reason for such a large spread is the long lasting reservoir of hypobiotic larvae that can be reactivated in pregnancy in the bitch, these are not susceptible to anthelmintics and so are only eliminated by preventing pregnancy or the death of the host.

''T. canis'' is present worldwide with a wide range of prevalances in different areas from 5 - 80%. Adult animals carry the fewest worms since initial infection causes immunity which leads to the shedding of adult worms from the intestines. The low parasite burden in adult animals can often lead to asymptomatic infection though the parasites wil still shed eggs in the faeces. The largest numbers of worms are found in dogs less than 6 months old who have not yet gained immunity to the worms. The high levels of prevalence of this species worldwide is largely due to the difficulty in controlling its spread. The eggs are extremely resistant in the environment and so can persist for several years. The females lay very large numbers of eggs, up to 700 per gram of faeces, making the removal of such a large number difficult. This final reason for such a large spread is the long lasting reservoir of hypobiotic larvae that can be reactivated in pregnancy in the bitch, these are not susceptible to anthelmintics and so are only eliminated by preventing pregnancy or the death of the host. As a result of the large number of infected bitches almost all puppies are born with ''T. canis'' infections which increases the spread of the eggs as they pass faeces in new environments once the litter is split up.

=Control=

=Control=

* Causes eosinophilic enteritis in the dog.

* Causes eosinophilic enteritis in the dog.

==== Significance ====

==== Significance ====