OK, let's take a scientific approach and see what the Chinese have told us at the beginning of their own outbreak...
The initial Chinese clinicians reported that the virus has an incubation time between 1 and 14 days and with an average incubation time of 5-6 days. Now the entire world uses a quarantine time of 14 days.
Whenever you go to a testing center and they question you what symptoms you have, including dry cough, sore throat, running nose, upset stomach, diarrhea, fever, shortness of breath, etc. The Chinese clinicians first reported the major symptoms. Now every country uses the same list to screen their patients.
Traditionally, fever has been generally associated with coronavirus infections. The Chinese first reported that a large portion of their patients do not have fever but still able to transmit the virus. Experts around the world were shocked and would not believe it at first. Now, fever is not the gold standard for screening COVID-19 anymore. Fever was the gold standard for SARS.
Traditionally, coronaviruses target the younger populations. The Chinese reported that the infection kills more elderly and those with diabetes, heart diseases and a history of smoking. Now everyone in the world talks about protecting your elders. And all the youngsters party on because they feel unaffected...
The virus kills more male than female.
Ventilators may not work for many critical patients because of the high fluid level in their lungs.
They were the first ones to test most of the available and possibly effective drugs and reported their efficacies. Now most countries with an ongoing outbreak only have a short list of the most effective drugs to try. that obviously has saved a lot of time since the doctors no longer have to waste their time to test useless drugs and as a result saving many lives that would have been lost when given an ineffective drug.
They were the first to report asymptomatic carriers might still transmit the virus, although experts around the world disagreed and thought it was "unlikely". Now, everyone talks about people who are not sick but can still give others the virus...
They were the first to report human-to-pet transmission. Nobody cared too much about that either and now the poor tigers in NYC got sick...
They were the first to show that a sudden surge of patients can overwhelm any health care system. Everyone else around the world sat back and laughed at the "incompetence" of the Chinese hospitals. "My Goodness, they don't even have enough face masks, the most basic equipment, for their doctors and nurses!" "what a bunch of idiots!" "talk about the backward Chinese health care system!"
I am listing just a few publications by the Chinese clinicians and scientists. Just a few since I don't have time to go back and find al of them.
Also, don't be misled by their official publication dates. Most of these studies had been put online for fast-tracked online publication by the journals in January and early Feb. Since most of the journals have planned out their official publications months ahead of time, they simply don't have space to officially publish these studies when they were submitted and accepted for publication. That's why the official publication dates are always months later.
And if you want to submit your work for publication in late Jan and early Feb, you would have to finish your study at least weeks before. That means most of these studies had been conducted in November and December, 2019, as they specify in their publications.
As the following study clearly specifies, they had suspected a huge number of unreported cases in Wuhan and flat out said it in their publications.
Don't underestimate these publications. These studies are obviously not intended for the general public. However, these studies are exactly how medical professionals communicate with each other around the world. And clinicians and scientists around the world rely heavily and, most of times, almost exclusively on these publications to gain knowledge of new diseases and new developments in the medical fields. Again, this is how medical professionals communicate with each other, not news briefings and going on media networks. Most of the doctors don't even know how to talk to a large crowd... So the Chinese medical professional have been constantly communicating with their colleagues around the world about the COVID-19, nonstop! And their counterparts around the world have all been listening carefully. The only unfortunate thing is that most of the governments do not acknowledge where they got their precious information.