Major will go to the temple entrance to speak with the native about the symbol. He has his bio suit on so he should get contaminated by those in the corridor.
Uhura remains in the same spot and will refuse any interaction with the contaminated ones in the squad.
Major will stop to examine Gault to see what is causing him to act this way. Using his comm he will check if Seth knows where the first aid kit is to see if there is something that can be used to stop the convulsions. He will continue to the native to see if he knows a way to help Gault and everyone infected. He will also inquire about the symbol.
Shocked by this sudden attack Major hesitates to shoots but then sees no other way to protect himself so.
Out of Character: I sent in the rolls via the FE combat dice.
Major tells Artemis not to move. He gets Seth on the comm to see if he can look after Artemis then he rushes back to where Uhura was to see if she either wants to put on the suit and check Gault or give him something to help Gault.