Strangers sticking fingers in baby's mouth

[Whatsinaname100]

I have a 4 month old daughter and we popped round my husband's offices where his friends were keen to meet bubba.

All was well, til an older lady stuck her knuckle in DDs mouth. I tried to say " you don't want to be covered in baby saliva"and gently move her hand away but she was having none of it. She let DD suck on her knuckle for 30 seconds.I looked on gormlessly.

Does anyone have any tips on how to stop this from happening politely but firmly. A phrase or action?

I don't mind close family doing this but this lady was practically a stranger. Call me a paranoid new mum but in all honesty makes me uncomfortable.

Tell her to get off, it's your baby, she's out of order.

Ok, so not so polite but you don't know where her hand has been and I would want her to stop immediately.

I wouldn't want anyone doing that, family or not. I don't even do that. I would just say that they're recovering from an illness so their immune system is too low.

I'm not a clean freak, dc1 eats food he drops on the floor and I've caught him licking shoes when tiny. I just find the idea of sticking fingers in their mouths repellent as many people don't wash their hands properly.