Tomato spacing in 4'x4' space?

[linzelu100]

I am building raised beds for next year, to help with drainage. 4 x 4 feet, 1 foot deep. I had a lot of issues with blight/dieseases on my tomatoes this year in my new home. I was thinking I should be cautious and plant one tomato per bed, so leaves don't touch. But if I prune instead could I plant more in that space? Is there anyway I could plant more in that space safely without increasing my disease chances?

ThaNks, Lindsey