BREAKING—First ever official re-infection case of #COVID19 documented. Research team from @hkumed report the first reinfection in press release. Patient reinfected by a completely separate strain of #SARSCoV2 from original, as proven by sequencing. Details & implications https://twitter.com/cwylilian/status/1297830744509698050

2) Note: out of millions of #COVID19 case, it is very likely that there will be a handful of reinfection. Many say it was inevitable that such a case will be someday found (which this HKU case seems to be), but how frequent is still a mystery.

3) according to the peer reviewed paper, accepted by CLINICAL INFECTIOUS DISEASES (link still pending), the patient was a young adult who was infected 4.5 months after initial #COVID19. The two #SARSCoV2 coronaviruses are from very different lineages/clades—I.e. not descendants.

4) The implications is that if true, reinfection could “persist” like other coronaviruses, and offer problems for long term immunity. But this still needs to be seen. Unclear impact on vaccine. And previously infected should still wear masks and distance. Let’s hope this is rare.

5) First #SARSCoV2 reinfection now reported also by major Hong Kong outlet @rthk_enews:

Patient was a 33-year old healthy male IT worker who was discharge in April, but returned from Spain w/ new #COVID19 illness from a different virus version. https://news.rthk.hk/rthk/en/component/k2/1545589-20200824.htm

6) “Health officials at first were unsure if the man was a "persistent carrier" of the virus from his previous infection.

But the HKU research team said genetic sequencing showed the virus strains contracted by him in April and August (after Spain trip) were “clearly different”

7) “Many believe that recovered Covid-19 patients have immunity against re-infection because most developed a serum neutralising antibody response. However there is evidence that some patients have waning antibody level after few months," the researchers said.

8) “Our findings suggest that the SARS-CoV-2 may persist in the global human population as is the case for other common-cold associated human coronaviruses, even if patients have acquired immunity via natural infection,” they said.

9) “Since the immunity can be short-lasting after natural infection, vaccination should also be considered for those with one episode of infection," they said.

They said therefore, patients who recovered after getting Covid-19 should also wear masks & maintain social distancing

10) Still awaiting the full paper’s link to be made public, and I expect people to discuss this a lot, so stay tuned. I’m going to post diff expert commentary in this thread later. Also, Re emphasize that this is likely very rare. Hopefully very limited circumstance.

11) In case of any doubt if press release is real or not— @hkumed posted the new reinfection study (to RTHK link) on their own Twitter too. https://twitter.com/hkumed/status/1297856984037896193