I would give the wipes a try on a discrete portion of the railing or treads and see how they hold up. If this is just a 1-time event to which you're being exposed, it may not harm the wood enough to worry about. Even alcohol could do the trick, and you can pass out alcohol based disinfectant wipes for guests, leavng a pretty trash can for them by the door. One thing I would do now and in future continuously would be to get some diffusers for essential oils and use an oil blend called Thieves. The name comes from the Middle Ages when thieves used this combo to cover face cloths or masks so they could enter the homes of plague victims to steal their stuff. It is a wonderful smell and helpful in destroying plagues of all kinds. Maybe you have time to modify and decorate your own mask to match your outfit for the evening if you don't feel comfortable without it. Try to have fun and not worry!

Minimize the stuff that has to be cleaned. You could cover your wood furniture with disposable tablecloths or some your husband can throw in the wash for you. Make the staircase inaccessible with a small rope across the bottom step, serving the same function as a velvet rope in a restaurant. Lock doors of rooms that you don't want people to enter.

Some surfaces coated with a good paste wax can be cleaned with a quick wipe of hot soapy water followed by immediate rinsing and drying with a clean terrycloth towel. If there are portable things that can't be cleaned, try storing them in the garage during the event. Take all the decorative objects off tables, countertops, etc. and take them to the garage. If it isn't there, it won't be handled or coughed on.

Thanks for weighing in. I decided that the whole thing was just too stressful and moved the party to a great 100 year old tiny neighborhood dive bar. The 15 of us will probably take up the whole place. The owner is letting us bring our own food in, is setting up tables and chairs, and the drinks are cheap. (The bathrooms are surprisingly spotless!) If someone is coughing or there are too many sniffles for me, I can simply retreat to the wonderful low germ bubble of my house!

No essential oils for me decoenthisiaste - super allergic to them!

Just wash your hands frequently and don't touch your nose or eyes.

Alcohol is the WORST thing you could use on finished wood! Jeez! Why would anyone recommend that?

The mechanical action of wiping is plenty. Clorox and Lysol are pointless overkill.

Consider the following:
In the time it takes you to read this sentence, your body will lose 7 million cells due to apoptosis (cell death).
In the time it takes you to read this sentence, your body will produce 35 million new cells.
Of all the cells in you body, less than half are human; the rest are the bacteria, etc. that we need to survive.

Perspective. Sterilizing/sanitizing your house is a fool's errand--can't be done. Just wash you hands and enjoy the party.

My mom is also immune compromised due to cancer and we use a product from Clorox that is a hydrogen peroxide bleach instead of chlorine bleach. It pretty rapidly turns to water so that may be less harmful to surfaces, especially short term?

I'm glad you decided to move the party. I was going to suggest that in lieu of trying to sanitize the furniture, handrails, etc. after the party, that you just wear gloves for 24 hours or so after everyone leaves. Germs don't have a long life span on hard cold dry surfaces.

I would be more worried about what is in the air with all those people around. I read somewhere that people do not even need to cough to send out germs. Breathing is all it takes to send out tiny droplets.

i know this post is old but It was the first thing that popped up in a google search for this kind of topic. So I fully agree with using essential oils in your home to help protect against germs BUT FYI MOST PPL DONT KNOW IF YOU HAVE PETS TO CHECK AND MAKE SURE THEY ATE PET SAFE OILS SOME ESSENTIA OILS CAN MAKE YOUR PET SICK OR EVEN KILL YOUR PET IF USED LONG TERM! so please research the oils you use if you have pets most are perfectly safe but you wouldn’t expect some that are on the bad list for instance wintergreen, peppermint, cinnamon, and pine are essential oils people commonly use that are bad for pets.. this is not a complete list of the oils bad for animals just a few examples.