While the time it takes for the virus to kill is exactly defined to be six hours, the time it takes for the visions to severely affect people is clearly intended to be variable (as some die instantly after the visions, while others are still free to act for several hours after their visions start).
With that in mind, it makes no sense that everyone in the mess hall is affected at the exact same moment.
McKay and Zelenka are playing Prime/Not Prime. McKay tosses out the number 4,021. Zelenka answers, "Ah, nice try. Not prime." 4,021 however, is a prime number.
McKay says nanotechnology is in the size of a billionth of a millimeter. It is actually in the size of a billionth of a meter.
When Major Sheppard and Teyla put on their hazmat suits they fail to tuck the hoods of their helmets into the neck opening of the suits, which would make them ineffective at protecting them from airborne pathogens.
In the game of Prime/Not Prime, 933 is not prime: it is ridiculously easily divided by 3. If digits add up to 3, 6, or 9, the number is divisible by 3, and therefore not prime.
The sound of the nuclear explosion is heard at the same time as the flash is seen. It should arrive several seconds later. Then again, the scale is all wrong anyway: considering the size of the generator, the camera point should immediately be engulfed in the nuclear fireball, yet there is not even a whiteout of the complete frame.
The team plans to use an electromagnetic pulse (EMP) to destroy a nanotechnology-based infection that is killing people. They make a great show of shutting down all of their computers to avoid the destructive effect of the EMP on electronic circuits. However, none of them turn off their radios, which are electronic devices, nor does Major Sheppard turn off the electronic equipment in Dr. McKay's lab. None of these devices are affected by the EMP, when they should have been rendered useless.
Dr. Beckett doubts the nanovirus can multiply, but that's of course the basic prerequisite for it to be able to infect people. If the virus count were constant, incubation time would get longer and longer and effects weaker and weaker the more people were infected because the virus would spread itself thinner and thinner.