Although the word news has an -s on the end, it is an uncountable noun, so:
▪ it is never used in the plural
▪ it does not follow a
✗ She now lives in exile, but the good news are that her words are heard over the world.
✓ She now lives in exile, but the good news is that her words are heard over the world.
✗ For too long we have ignored these news.
✓ For too long we have ignored this news.
✗ Many countries have banned smoking in public places. This is a good news for non-smokers.
✓ ...This is good news for non-smokers.
Q: How can I refer to a single item of news?
A: You can use news on its own, or say some news or, less frequently, a piece of news.
Bush was in a meeting when he heard news of the attack.
I have some news that may cheer you up.
I just got a surprising piece of news.