I won't give my introduction again, see my first post "An Introduction." What I will remind any readers is that I am not a doctor. This is my speculation. And it may all be nonsense.
I won't try to quote specific numbers, and here I am focusing only on China. What I saw in the reporting was that China's infected numbers grew to about 75,000 and then seemed to stall. In the meantime, numbers started growing around the world.
From all reports, it seems easy to catch. People on ships, people traveling to Italy or China, just about anybody in contact with an infected person seems to get sick.
An early BBC report from China, after they isolated the city in Wuhan, showed that they allowed people to go in, but not to come back out. At least that's what the crew reported. They then went in, and a little while later, Chinese police escorted them back out. Peculiar. Also, a recovered Chinese national claims that when he went to the hospital early in the epidemic, the Chinese medical staff were wearing full HAZMAT/infectious gear that he had seen only in movies. The Chinese seemed to think it spread easily.
So why did the Chinese numbers stop climbing? Either the numbers actually stopped climbing, the Chinese are lying, or they simply stopped testing/reporting on the numbers. I hope the former is true, but really suspect they've stopped formal testing and/or reporting.
Think about the quarantine or isolation procedure. Suppose in a city of 1 million, 20,000 people have the virus, and the government stops people from leaving the area. Would anybody enter that didn't live there? Further, suppose they had an extremely large infectious disease isolation capability at the city hospitals that could handle 1,000 people at a time. The rest (19,000) are told to self-quarantine at home. Do they go to the store for food? Or do their relatives, who then have to get the food to the infected person, do the shopping for them? Self-quarantine, except for the survival hermit out in the woods, is not going to stop person-to-person contact with the sick. Of course, everyone is going to minimize person-to-person contact and hopefully use good hygiene procedures to minimize contagion.
While the spread may be slowed, it's going to grow from an ever-greater base. 19,000 will become 25,000 then 30,000.... With the 14-day incubation period, there's going to be person-to-person contact. But now, who's going to get the test kits into the city or the medical supplies needed? I presume the Chinese army would use HAZMAT protection to deliver food, medicines and supplies. At least to the extent protective gear is available.
They say half of the population of Wuhan left before the lock-down. Some of those must have been infected and would be spreading it further.
I just don't understand a stall of the numbers. Unless masks work, or most people are on a self-sufficient homestead and do not need or desire to socialize or shop, the numbers should not have stalled. Most likely, it's the Chinese government not reporting numbers that would induce a panic.
But there might be one other situation where an infected-number stall is reasonable. Oftentimes, you need a certain 'number' of pathogens to get sick. Your body can fight off a small number, in many cases. Suppose a high-density release started the epidemic, and high population interaction extended the initial spread. Then the Chinese minimized person-to-person interaction, all of the sick started wearing masks, and good quarantine was provided to the really sick. The spread per person might drop off with each 'wave' of newly sick. Resulting in an eventual stall.
I suspect that happened with SARS. But I don't really think it happened with COVID-19. Since most of the symptoms look like flu, unless you do the right tests, it would be easy for China simply to classify most non-lethal cases as flu rather than coronavirus. Simply order the hospitals to stop doing COVID-19 tests if the patient does not need the ICU.
Anybody see any CDC or WHO reporting from on-site Chinese health facilities in the affected areas?