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What’s the good news this week?

Question: I liked the good news round-up from (last week?). What’s the good news this week?

Answer: Yeah, that was only a week ago. It feels somehow much longer ago…. time is especially strange these days. Anyway, we do have some good news from the last few days, so let’s embrace it!

  1. Vaccines and Lasting Immunity: Three days ago,Cell published a paperfrom a team of researchers across CA, NC, and NY (Mt. Sinai!) further examining adaptive immunity to SARS-CoV-2 to inform vaccine development. Researchers examined T cells — both T Helper cells (CD4) and T Killer cells (CD8) — of non-hospitalized people who recently recovered from COVID-19 and people who were never infected. Reminder: for an overly simplistic review of immune functions see Q&A of 5/9. This paper is not an easy one to read, so I greatly appreciated this Science blog that described the study and its results in more lay terms. In essence, the study found that (quotes are from the study itself):
  • “CD4+ T cell and antibody responses were observed in all COVID-19 cases, and CD8+ T cell responses were observed in most.” Among those who have recovered, researchers observed a robust adaptive immune system response, which means that immunity is likely to be [relatively] lasting.
  • “These data suggest that a candidate COVID-19 vaccine consisting only of SARS-CoV-2 spike would be capable of eliciting SARS-CoV-2−specific CD4+ T cell responses of similar representation to that of natural COVID-19 disease.” This means that vaccines targeted to the Spike-protein may indeed be quite effective! Additional data in the paper provides direction for further vaccine enhancement.
  • “Pre-existing SARS-CoV-2−crossreactive T cell responses were observed in healthy donors, indicating some potential for pre-existing immunity in the human population.” Some exposure to other types of coronaviruses may be protective (cross-reactive immunity)! And this could explain why the severity of the disease varies so dramatically. More research is required, but this is a fascinating bit of information to add to the pile.
  • “Clearly more studies are required, but the data here appear to predominantly represent a classical TH1 response to SARS-CoV-2.” This means that there was no evidence of an antibody-dependent-enhancement response, which would have been very bad. Note: antibody-dependent-enhancement response occurs in diseases like Dengue where the immunity a person builds form a previous bout with the disease (or vaccination) actually makes clinical symptoms worse and the risk of severe outcomes higher if the person is subsequently infected.

2. Pregnancy: Earlier this week, a pre-print (not yet peer reviewed) article was released from a group of researchers across the UK describing “on a population-basis, the risk factors, characteristics and outcomes of pregnant women hospitalised with SARS-CoV-2 in the UK…” Researchers used a national observation study to study risk factors between 427 women who were hospitalized with SARS-CoV-2 and 694 women in the comparison cohort. In good news, the researchers found that pregnant women hospitalized for SARS-CoV-2 were no more likely than the general population to require respiratory support. Additionally, researchers report that “the majority of [pregnant] women do not have severe illness and that transmission of infection to infants of infected mothers may occur but is uncommon.” [Now, there were some findings in this paper that definitely don’t fit in the good news category — like increased association between black and minority ethnicity and hospitalization with SARS-CoV-2 during pregnancy — but we’ll save those important findings for different Q&A].