If it is killing your tree, google fire blight on pears. Read up and follow the suggestions. Any university extension services should have info on fire blight.

That sure doesn't look like fire blight to me. I would need to see a lot more of the tree to be certain but it looks more scab-like than FB. In general, at this time of the season just a few short weeks before the trees start dropping leaves and entering dormancy, I am not overly concerned about leaf disfigurement. Just rake up and dispose of all the leaves and use a dormant spray with fungicide in late winter.

In spring after the tree leafs out and if the problem persists, take samples into your extension service office for diagnosis. They will recommend appropriate treatment.

Thank you guys for your responses, here are more photos. The problem is, after the leaves have fallen off during the Winter the problem comes back in the summer and I don't know how to treat the disease.

Thanks

You have to identify it before you can know how to treat. If the problem recurs every year, then take samples in NOW for an ID and treatment recommendations. If it is scab, you want to start treating this winter.

Thank you for your reply, from the photos does it look like scab to you or something else? I am new to this and don't have much knowledge on the topic.