Be careful with bleach. It is easy to end up with serious concentrations of chlorine/chloramine gas. When your nose is working the smell would warn you and you can escape the area and ventilate befor eany real dmamge is done.

When the nose is stuffed up and the sense of smell dulled by flu your first warning may be when you start to wheeze. Unfortunately by then a lot of damage could be done. Adding chemical pneumonia on top of flu is a lousy way of getting better faster.

So use bleach heavily diluted and with great care if you chose to use it at all. According to my local health expert bleach is, in most cases, overkill for normal use. Simple soap and water is as effective for most household cleaning unless there is a reasonable expectation that hepatitis, HIV or tuberculosis are present.