Zombie Maintenance:

The Zombie bacteria/virus was pretty nasty.  Some very powerful people had gotten infected and they had plenty of money to try to find a cure, but it didn’t help.  This was way out of the league of anything we had faced before.  The infection could pick up genetic code from anything that if was exposed to.  The Rhabdoviridae family of viruses was the worst for being absorbed.  Deceases like Rabies started to show up in the Zombies.  This was really bad.  When the brains get hot or infected the Zombies get much more aggressive.  Up in NYC was not so bad.  We had very few animals to that had Rabies and only a few weeks of hot weather, typically.  In the south I heard it was much worse and Georgia and Florida had quite a time with their Zombies especially in Tallahassee.
Keep your Zombies as cool as possible.  They should not be allowed to freeze, but they like the cold.  If they do freeze, warm them slowly to prevent as much cell damage as possible.  They will look funny with freezer burn.  They work best when underground and kept cool.  Most chemicals do not bother them, they rarely breathe.   They work extremely well in areas with high CO2 concentrations and other pollutants, but caustic chemicals can burn off what is left of their skin.  Many Zombies can function at reasonably high levels if they are well maintained.  There have been many reports of people put into cold storage on the first signs of infection.  Once a Zombie they still show signs of recognizing family and friends and show a generally gentle and compliant attitude.  Do not let Zombies gather into large hordes.  They become agitated and difficult to handle.  They will naturally hoard together if not watched over.
Zombie stink can get pretty bad.  My brother was complaining about the stink of his live-in Zombie stripper girlfriend (you do not want to know) and I remembered a TV show about the 50s and people were walking through large vats of carbon tetrachloride to dry clean their clothes.  Of course we found out the chemicals of the time were highly toxic and people do not walk through vats of toxic corrosive chemicals anymore; at least living people do not.  With a little research I found that carbon tetrachloride was banned in the 1980s because of concerns over the environment and it was accused of destroying the ozone layer.  I am not sure how a chemical much heavier than air is supposed to get 60,000 feet up to reach the ozone, but I am not going to argue the point.  These days dipropylene glycol tertiary-butyl ether is used to be friendly to the environment and not cause horrible flaming accidents.  I guess that is good, we would not want flammable, yet clean, Zombies walking around town.