Murder mystery set in England

A person has a cut or scratch and dies because the person treating the cut puts bacteria in it.
There is a love story in the book also.

There is possibly a young doctor who comes to the town to replace the old doctor.

Around when did you read this? Recently? Many years ago?

Was the story setting contemporary?

I listened to the book some time in the last 2 years. I can’t find it in my listening history. I thought it was Agatha Christie but I can’t find one that matches. The main character could have been the young doctor. The story was told from the point of view of a person who was either new to the town or visiting. One character was a mother with an adolescent son who misbehaved. The main character also found a girlfriend.

Not sure if it was contemporary. They had cars and electricity and probably telephones.

Maybe look at the Christie work, Cards on the Table? It ends on a courtship and one of the deaths involves blood infection, but I have no idea if it matches the 'young doctor' detail.

https://en.wikipedia.org/wiki/Cards_on_the_Table

edit: Oh, Murder is Easy might fit better:

After inviting Humbleby round to her house, she cut his hand with scissors. She then applied a dressing to the wound, a dressing with pus seeping from her cat's ear; Humbleby dies a few days later from blood infection.

Zero young doctors, from what I see, but also ends on a courtship.

https://en.wikipedia.org/wiki/Murder_Is_Easy

It was Murder is Easy. That’s amazing how did you find it? Thank you. That was driving me crazy.

You're very welcome! This one was lucky Googling and your hint to Agatha Christie was a great clue. I found it using the keywords 'sepsis' and 'agatha christie'.