Yes that’s 28 days later. But they made them only act aggressively towards noninfected. So supercharged zombies in a way but they’d die after some time without food.
I won’t assert it as fact but I think rabid animals can’t distinguish between healthy and infected individuals. If not, the infected would just tear each other apart. It’s a desease; group instinct requires higher cognitive capability.
And our bodies can last for about 3 weeks without food, assuming we are doing our best to conserve energy. Again, last 28 days and your chances of surviving go up.