I thought
Last Ones Left Alive by Sarah Davis-Goff was excellent. Not traditional zombies, but near enough and very creepy.
I just finished Bobby Adair's
Slow Burn series (already mentioned several years upthread) and it was terrific.
The
Survival Instinct series by Kristal Stittle (five books) was quite good. There's also the even more lengthy
Green Fields series by Adrienne Lecter.
I enjoyed
Weep: The Irish Epidemic by Eoin Brady. It seems that there's a second book in the works but there were no details last time I checked.