The phrase得了in this context of an illness means "got" or "contracted".

得了 literally means "got", used only with sickness or disease. Typical usage is 得了xx病/炎/症 e.g.: 他得了心脏病 这小孩儿得了肺炎 她四十岁的时候得了抑郁症。 了 represents it already happened.

there is another interesting usage of 得了. A : 你刚搞对象去了？ B:得了吧!

小明说自己 得了 感冒。

thank you, can you think of any other example sentences that use 得了 that could help me understand its proper usage? many thanks