Goofs

Quark and Odo refer to Rom being an engineering idiot, but later he'll become an engineer for the station and quite talented.

The device is said to build the virus directly into the replicated food, however a replicator can't create life which, although simple, a virus is.

While there is still debate, current thinking is that a virus is not in and of itself, alive. It requires other living cells to replicate.

As people started getting the aphasia virus, they were not incapacitated immediately, and they were brought to the sick bay to be monitored. When Sisko got infected, he started babbling, then, started sweating, then collapsed. Soon after that, Kira got infected and started babbling, but she realized what was happening, so she calmly sat there and watched the doctor she had abducted from Bajor as he worked on trying to create the antidote. However, people can react to the same virus in different ways in reality, so Kira and Sisko having different symptoms is not an error.

O'Brien is the first to contract the virus as he worked on the replication which contained the device, however the device didn't activate until after he ordered his coffee so he shouldn't have been affected.

When Dr. Surmak examines Dr. Bashir's notes on his attempts to create a cure one of his entries says he contacted Chief O'Brien to request the environmental engineering data for the previous 24 hours. However Chief O'Brien was patient zero, prior to him becoming symptomatic Bashir didn't know about the virus. And Bashir certainly couldn't have contacted O'Brien after he became ill since O'Brien wouldn't be capable of understanding Bashir.

O'Brien is the first to be affected by the virus and is taken to the temporary emergency sick bay that will be used for all patients. No one contacts his wife to tell her what's happened.

Once it was realized that the virus had mutated to being airborne, why not have everyone wear some form of breathing apparatus? There probably wouldn't be enough for everyone, but more could have been replicated.

When everyone starts contracting the aphasia virus there is a lot of frustration as they are unable to communicate with each other. They all have pads. Surely thy can type out what they want to say.

Sisko goes into the infirmary to meet an infected Jake. Bashir says they've converted empty crew quarters into a ward. Sisko says he'll take Jake there and leaves before Bashir specifies where the quarters are located.

When talking to Odo in his vacant bar, Quark refers to Rom as his assistant. It has already been established that Rom is Quark's brother, and Nog, his nephew.