Answering your question, Sheikh Ahmad Kutty, a Senior Lecturer and an Islamic Scholar at the Islamic Institute of Toronto, Ontario, Canada, states:
Why Are Dogs Considered Impure in Islam?
Since dogs, in general, are not considered very clean animals as they can be carriers of numerous parasites some of which may be highly harmful to humans, Islam is against adopting dogs as pets.
And as most of these parasites are passed on to others through their saliva, we are told to wash the spot it has come in contact with seven times, one of which should be preferably with mud/dirt.
Having said this, however, I must point out that as some scholars have ruled that washing the spot with anti- bacterial soap will be deemed as sufficient instead of using dirt or mud.
Exceptions to Dog-Related Hygiene Rules in Islam
While some scholars consider the entire body of a dog as impure, many, however, are of the view that it is only its saliva that is considered as impure in an absolute sense; so that is what we should stay clear of at all times.
The above ruling about the impurity of dog in general or of its saliva in particular notwithstanding, there are certain allowances allowed for those who are unable to avoid contacts with dogs because of the nature of their job involving dogs or specific circumstances which make it hard for them to avoid direct contact with dogs.
Guidelines for Handling Dogs and Their Owners
In this category, we can include farmers who keep dogs for guarding and shepherding cattle, etc; people who are visually challenged who need to keep dogs as guides, hunters who use trained dogs, police who employ trained dogs for investigating crimes, those who need to keep guard dogs, etc.
As Imam Ibn Taymiyyah has pointed out, because of the particular circumstances such people find themselves which make it impossible for them to stay completely clear of dogs, they are allowed certain relaxations in regard to purity and impurity associated with dogs. This is because of the general principle of taysir (ease and removal of hardship) inherent in the Shari`ah which teaches that ‘wherever there is hardship, the rigor of the law is relaxed’. In other words, they will be excused as long as they do their best as determined by their own circumstances, for “Allah (certainly) will not impose on a soul a burden it has no strength to bear.”
What to Do After Touching Someone Who Handles Dogs?
In conclusion, if you are certain that you are in contact with the saliva of dog then you should wash the spot clean with soap.
If you touch someone who handles dogs, it is good to wash your hands, for your own good; although there is no compelling religious ground to do so.
