The CNN headline for the article you linked to is:
"WHO says no evidence shows that having coronavirus prevents a second infection"
The second paragraph of the article literally quotes a published brief from WHO:
"There is no evidence yet that people who have had Covid-19 will not get a second infection," WHO said in a scientific brief published Friday.
The headline is literally taken from the WHO's actual words. There's a case to be made that these sort of articles need to be more deeply contextualized with respect to how science works and what the implications of findings are (and what they aren't), but that gets into deeper questions about scientific literacy -- not just for journalists, but for their audience -- but it's hard to point at this and say that this reporting is making it look like the WHO was saying something that they weren't.
It's just poor communication, anybody who parrots 'evidence' to the average audience will know full well that 'no evidence' => 'evidence _against_ something'. That's a really, really basic way to mess up when communicating this. I don't know why it's so bad. I think this is certainly a case where an educated journalist should not simply consume literally the WHO's output, and should instead term it in ways commonly understood to be closer to the truth.
The final 3 paragraphs of the 9-paragraph CNN article are a quote from a non-WHO expert doctor on the subject of the article. It does look like they tried to contextualize it and not just literally repeat the WHO announcement.
I would put more blame on the WHO for this than CNN in any case. It’s fair to say the way the WHO reported this was misunderstood, but the WHO themselves tweeted the same type of wording out directly on Twitter.
"WHO says no evidence shows that having coronavirus prevents a second infection"
The second paragraph of the article literally quotes a published brief from WHO:
"There is no evidence yet that people who have had Covid-19 will not get a second infection," WHO said in a scientific brief published Friday.
The headline is literally taken from the WHO's actual words. There's a case to be made that these sort of articles need to be more deeply contextualized with respect to how science works and what the implications of findings are (and what they aren't), but that gets into deeper questions about scientific literacy -- not just for journalists, but for their audience -- but it's hard to point at this and say that this reporting is making it look like the WHO was saying something that they weren't.