This is very worrisome. Among recovered former #COVID19 cases, “nearly a third had unexpectedly low levels of antibodies. In some cases, antibodies could not be detected at all.” https://www.scmp.com/news/china/science/article/3078840/coronavirus-low-antibody-levels-raise-questions-about

2) “Whether these patients were at high risk of rebound or reinfection should be explored in further studies,” the team wrote. #COVID19

3) Antibodies are generated by the immune system and have unique chemical structures to inhibit specific pathogens. The coronavirus antibody intercepts the spike protein on the viral envelope to prevent it from binding with human cells. #COVID19

4) “researchers said they were surprised to find that the antibody “titer” value in about a third of the patients was less than 500, a level that might be too low to provide protection.” #COVID19

5) “About 30 per cent of patients failed to develop high titers of neutralising antibodies after #Covid19 infection. However, the disease duration of these patients compared to others was similar," they said.

6) “The team also found that antibody levels rose with age, with people in the 60-85 age group displaying more than three times the amount of antibodies as people in the 15-39 age group.” #COVID19

7) low amounts of antibodies could affect herd immunity, resistance to the disease among the general population to stop its spread. “What this will mean to herd immunity will require more data from other parts of the world,” Professor Huang Jinghe, leader of team, said. #COVID19

8) “Vaccine developers may need to pay particular attention to these patients,” Huang said. If the real virus could not induce antibody response, the weakened version in the vaccine might not work in these patients either. #COVID19

9) The researchers also found that #Covid19 antibody could bind with a distantly related strain SARS-1 in 2003. But the binding could not suppress SARS-1 virus replication in cells, dashing hopes of developing a vaccine for two or even more coronavirus strains at once.

10) “Who knows whether #COVID19 will become something like seasonal flu, or chronic disease like hepatitis B, or just vanish like Sars?” he said. “Up till now we still lack imagination [to tell].” Translation: now it’s looks worse than before.