He nursed for five years and we restrict sugar and junk foods. I never use antibacterial cleaners at home. I'm not the last bit worried about my vaccine choices.
I would also worry if I'm honest. 5 months old is awful young to be exposed to kids up to 3 and all the potential germs they carry around. Probably it'll be fine of course, but I personally would feel terrible if it wasn't because my child was not vaccinated.....
I think pertussis would be my main concern - MMR comes much later in the recommended schedule anyway. Pertussis in young babies can be serious, and while the vaccine isn't 100% protection it does lower the risk enough to be worth doing in my opinion.
But as pepperedmoth said we don't know the full story. Some children cannot be vaccinated, and there you just have to trust to enough immunity in the kids around your daughter to prevent the diseases spreading to her.
Just a final comment that shedding from other kids vaccines is extremely rare as to be something you really shouldn't worry about (only relevant for live virus like chicken pox anyway).
Mother of two living in UK. Daughter (2007) born in USA, son (2010) born here. I'm pro natural birth, midwife care, breastfeeding, co-sleeping, baby wearing and a keen advocate of cloth diapering. I'm a full time working research scientist (physical sciences). Vaccines save lives.