Unlike anonymous users online, professional scientists can't make a claim, especially a very serious one, without evidence. If they do so, later the public will crucify them if it turns out the virus actually cannot spread from human-human.
It's only in the past three days that it because clear that there is evidence of people who don't have a direct link to the market being infected. A big reason for this breakthrough was that the genome of the virus was identified (by, yes, Chinese scientists working within two weeks of realizing a novel outbreak, which is also impressive). This genome sequence makes possible very sensitive tests for identifying infected people more accurately.
Hence, in the light of this new information, the scientific consensus has been updated to reflect likely human-human transmission.
Please stop spreading false information and unnecessary hatred. This only makes the response to a crisis worse.
Now the government is getting criticized for this by e.g. Hu Fanzhu of East China Normal University's National Discourse Environment Research Center, whose open letter you might want to read if you think stopping people from "spreading false information" is what's important here.
From wikipedia:
> The first suspected cases were reported on 31 December 2019
Some people have some weird imagination
Firstly there isn't one case confirmed in HongKong yet.
Secondly, the virus could take up to 2 weeks to start showing symptoms and it is only until recently the method to detect this virus efficiently had been discovered.
This is a new virus, and its behavior takes time to understand.
[0], [1]
I agree this is a new virus we know little about, but did you know folks in Wuhan were still gathering in crowds without any precautions [2], and ppl got caught spreading so-called fake news of this virus?
[0] https://twitter.com/alvinllum/status/1219911842723553283
[1] https://news.rthk.hk/rthk/ch/component/k2/1504214-20200122.h...
[2] https://twitter.com/Xhnsoc__Redflag/status/12194676125282181...)
Now they suddenly started to release updated numbers (due to pressure from their neighbouring countries) and you think it'd only "escalated in a week".
Some people have some weird imagination
* http://www.chinadaily.com.cn/a/202001/01/WS5e0c6a49a310cf3e3...
Where is due to the pressure part? At first there had not been showing enough evidence of the virus's capacity to spread from human to human, which only confirmed recently because the medical staff gets infected and 2 cases in Guangdong, so the alert level is much lower than it is now.
You can blame the Chinese authority for not fully predicting the severity of the situation, but intentionally covering stuff up is a different accusation you better have strong evidence to support that.
Some people indeed had some weird imagination.