Hello, I have a 9 yo female mountain cur. She's due for 3 year vaccine booster. In 2016 she was given DHPP. I would prefer to boost her with...

Hello, I have a 9 yo female mountain cur. She's due for 3 year vaccine booster. In 2016 she was given DHPP. I would prefer to boost her with DAPv only and skip the parainfluenza (non-core vaccine). My rationale is because I don't want to burden her immune system with anything that isn't absolutely necessary. She's getting older and has been on daily Apoquel and sometimes predisone for several years now to treat bad allergies. My understanding is the risk for parainfluenza is from contact with other infected dogs, but she's aggressive towards other dogs, so is not allowed around other animals. She is not boarded. Is there any other way for her to become infected with parainfluenza? There's a risk/benefit of the parainfluenza vaccine that I'm weighing.

Thank you!  Yes, very helpful info.  We do walk her in parks and other areas where dogs have been.  She's always sniffing, so I wondered if she could pick up the virus from that indirect type of exposure.  We also travel with her and stay at pet friendly hotels, so I guess that could be another source of potential exposure.  I hadn't thought about asking for titers!  Will dicuss with my vet.  Appreciate the advice.  Always nice to get a second opinion.  Love this service!  Will use again and recommend to friends!