Thread by @DrEricDing

📍Huge—ANOTHER PROVEN RE-INFECTION—This one is much more serious than Hong Kong reinfection. 25-year-old patient from Nevada got sick March 25th, recovered (2 neg tests), but got *EVEN MORE SICK* May 28th & hospitalized. Key—completely distinct 🧬 #SARSCoV2 coronavirus lines! 🧵

2) Reno, Nevada patient tested PCR #COVID19 positive April 18th, recovered April 27th, then tested negative May 9th and negative again May 26th. But started feeling unwell May 28th, and then went to family doctor June 5th, found hypoxic, sent to ER, and hospitalized same day.

3) “patient required ongoing oxygen support and symptoms: myalgia, cough and shortness of breath. A chest x-ray was performed on 6/5/20 and compared to that of 5/31/20 with the development of new patchy bilateral interstitial opacities suggestive of a viral or atypical pneumonia”

4) “On 6/6/20, the patient was tested for IgG/IgM for SARS-CoV-2 and was positive.

There was “symptomatic recovery; a period of 48 days, and two
9 non-reactive (neg) SARS-CoV-2 test results”.

So they then genetic sequencing of the viruses from the different positive cases...

5) While A and B cases part of same general clade, case A had 5 further single nucleotide variants (SNVs) compared to reference 🧬. Sequence of case B show 6 extra SNVs and a mutation at position 14407,”

➡️ RNA of viruses different.

6) “Case A had four SNVs that are absent from the later case Bc while case B had seven SNVs absent in the former. There were an additional three 🧬 deletions and one insertion in Case B sequence relative to the reference.”

7) Basically, while virus case A and B part of general clade group, they are diff. “For A to experience mutations to become case B, the virus would have had to exhibit a rate of 83.64 substitutions per year, a rate exceeds that of 23.12, currently observed” by 3x—ie unlikely same

8) “enormous significance, four of the discordant loci seen between case A and case B would be reversions specific to the ancestral genotype. The odds of this occurring are vanishingly remote and ***virtually assure that these are two distinct viral infection events***”

9) More importantly—unlike Hong Kong reinfection case where 2nd infection was asymptomatic mild, this Nevada person’s reinfection was SERIOUS that it needed hospitalization in June whenever the first March infection did not need hospitalization!

10) Study thus notes: “An implication of this finding is that initial exposure to the #SARSCoV2 virus may not result in a level of immunity that is 100% protective for all individuals” 📌

11) BOTTOMLINE: A young 25 year old got sick twice, from two different #SARSCoV2 viruses that were 🧬 distinct. And the second infection (the reinfection) yielded #COVID19 illness much worse than first, despite recovering in between. Recovery from 1st didn’t protect from 2nd.

12) Another key point I forgot to highlight—“On 6/6/20 (hospitalization day) the patient was tested for IgG/IgM for SARS-CoV-2 and was positive”. Usually antibodies takes weeks to develop. So these antibodies were likely from the first March/April infection. Yet didn’t protect.

13) Authors acknowledgement: “Nevada IDEA Network of Biomedical Research (INBRE) for supporting this work and the publication was made possible by grants from the National Institute of General Medical Sciences of the NIH.”

Link to article: papers.ssrn.com/sol3/papers.cf…

14) Also key was the roles of local health Dept and sheriff Dept in tracking down cases! It’s all part of a greater effort to get these results: “We also thank the Washoe County Health District, Washoe County Sheriff’s Dept for helping to identify and confirm these findings.”

15) A virus and immunity expert also weighs in and agrees this reinfection case study is concerning.

https://twitter.com/virusesimmunity/status/1299342270177726464