Thread by @DrEricDing

📍TROUBLING. “Danny Altmann, professor of immunology at Imperial, guesses recovered patients from #COVID19 have perhaps 90% protection for a “fair while”. But how long? “I would bet my house on you being safe for possibly a year but not much longer” 🧵 theguardian.com/world/2020/oct…

2) “The problem is that whenever an immunologist says anything about Covid immunity to a journalist, it’s right for about two weeks and then it’s completely wrong.”

3) “It’s really hard to find a pattern right now,” said Akiko Iwasaki, @VirusesImmunity, a professor of immunobiology at Yale University who has been following cases of reinfection closely. “Essentially every case is different.”

4) “So far, only two dozen or so reinfections have been confirmed worldwide in a pandemic that has infected more than 30 million people. For now at least, reinfection seems uncommon. But scientists point out that confirming reinfection is no easy task and many cases are missed.”

5) “In a report on reinfection in India, Prof Jayanthi Shastri and her team in Mumbai describe a 25-year-old nurse. “Her immunity wasn’t enough to protect her from the second, more severe infection despite the presence of neutralising antibodies,” Shastri said. #COVID19

6) “handful of questions that scientists are struggling to answer. What does protective immunity look like? How long does it last? Do some patients fail to mount the right response? Does the virus damage the immune system? And are reinfected people infectious to others?”

7) “Reinfections may be worse for a whole host of reasons. The person might have been exposed to more virus the second time around, or may simply have been under the weather already when the virus struck again.

8) “Another possibility is so-called antibody-dependent enhancement – a glitch in the immune system where antibodies help an invading virus rather than hinder it. This is seen in dengue fever where second infections can be far more dangerous than the first.”

9) “In August, Shiv Pillai, an immunologist at MGH examined tissue taken from dead Covid-19 patients. He looked for structures called “germinal centres” in spleen & lymph nodes. These are where B-cells go to develop antibodies before they are stored in immune system’s memory...”

10) “Pillai **failed to find any**, suggesting the patients were unable to generate highly effective, long-lasting antibodies that would fight the virus for years.
He believes the same problem may arise in people with milder Covid-19 too.”

11) “If we want antibodies that will persist for a few years and protect us, it’s not clear that’s going to happen,” he said.”

12) “The good news is that a vaccine should not cause the same problem as the virus. “I don’t see why the vaccines won’t work. They may not be fantastic, but I believe that’s what’s going to protect us,” he said.

14) earlier reinfection thread. Note there are now 22 officially confirmed. And again they are really hard to find.

https://twitter.com/drericding/status/1311049145759694848