30 March 2020 Extent of European epidemic - Genetics of COVID disease - Gastro-intestinal involvement

Mon, 03/30/2020 - 23:55
  1. First a worrying and encouraging report by the Imperial College.  Based on a “hard outcome” i.e. death and the evolution after the strict measures, they applied advanced statistics (that I have to believe) and calculated:
  • What percentage of the population is infected in 11 European countries: 2-11.5 % or between 7 and 43 million !
  • How many deaths averted by the measures: 59,000

What everybody could presume already: Italy and Spain are hardest hit, Germany least of all , but the actual (calculated) numbers in Table 1 are still remarkable: in the worst case, up to 26 and 40 % of the Italian resp. Spanish population may be infected, 1.8 % in Germany and the other countries in between.  Please have a look at the very instructive graphs and Tables.  

  1. Everybody is wondering about genetic predisposition factors for COVID-19 disease.
  • A very preliminary report from China suggests that ABO groups have a role: A would be worse than non-A and O better than non-O.  If you look at Fig 1 p. 17, I would say that the protective effect of O is more convincing 
  • Two authors from Stanford acknowledge these findings and studied he relation of combined hematological parameters observed in severely ill COVID patients (lymphopenia, neutrophilia, low esosonophils and basophils) in large databases, containing info on active viral infections.  Based on these very preliminary modeling they propose to focus more studies on 1) HLA typing; 2) ABO blood-group; 3) “Polygenic risk score weights across hematological measurements;”

Well, sounds good. I’ll let you know as soon as there are real data….  

  1. Continuation of our discussion on the role of GE involvement.
  • A short data paper in The Lancet Gastroenterology & Hepatology by Yongjian Wu et al from China: they show that in more than half of their patients the fecal samples remained positive for almost a month after onset of symptoms and on average 11 days after the respiratory samples turned negative.
  • The opinion paper in the same journal by Charleen Yeo from Singapore that there is also quite some “circumstantial evidence” that also the “old” SARS and MERS were not only found in stools, but could remain viable and infectious in sewage water and fomites. ACE2 (for SARS-CoV-1 and -2) as well as CD26 (for MERS) are found in the gastrointestinal epithelium
  • An abstract that I could not get access to the full paper, further support the GE tract involvement in COVID infections.

So, the practical advice to COVID patients is obvious: keep taking care of hand hygiene, use a separate toilet at home, clean it yourself  and avoid using public toilets, at least for a while after your recovery….