Circuit board layout: wifi ceramic antenna next to a electromechanical relay
It's much more likely that electrical noise from the contacts switching will scramble the Wifi momentarily. If the relay switches infrequently there's probably enough safeguards built into the protocols that the effect won't be obvious. 

Here's an example of a low-end power relay mounted a couple inches from a PCB WiFi antenna: 



You may be better off than the above example with your ceramic patch antenna if you orient it so the ground plane is between the relay and the antenna.