Thank you so much for your insights. I look forward to your posts on Twitter. I have been fascinated by the shifts in viruses as well. I’m a pediatrician in southeastern United States. We experienced a huge wave during delta which was very scary because the adult beds were being taken up by delta and the ped’s beds by rsv.
I am more inclined to credit viral interference for the shift of the viruses:
1) the drop off in all other viruses happened prior to wide spread masking or social distancing. Excellent article by Dr. Christopher Harrison, infectious disease at UMKC (Kansas City, MO) which demonstrated every virus falling off early March except rhinovirus which he called the cockroach of viruses. 😂
2) most transmissions happen in the home setting. Therefore, the weather only plays a role via humidity and not personal behavior. Also, I’m in the south and we are a slovenly group who stays inside most of the time anyway!
This study has fascinated me because it is a retrospective study looking at how viruses interact and how they can shift the spread of other viruses. https://pubmed.ncbi.nlm.nih.gov/34968374/
I’m also personally doing a study of rsv/Covid in the outpatient setting. I’m looking at rapid antigen testing of those tested for rsv and Covid. So far, none are “co-infected.” I think the hospital numbers showing coinfection are skewed because they are often pcr. This may pick up an infection as far back as 6 weeks prior and doesn’t represent which is the cause of their hospitalization.
Thank you again for your work and your reasoned response during the pandemic.
Your thesis seems to consider each virus - and immunity to it - in isolation and the downside of the reduced exposure is hence limited to the number of cases which might occur simultaneoulsy as the immune debt is "repaid", rather than the severities of infection which might be expected.
Do you think, however, that in fact low level constant exposure to infection (esp rhinoviruses and coronaviruses) might have non-specific priming effects on the innate immune system, such that depriving children of these might make them more susceptible to severe illnesses from RSV or influenza viruses?
This would seem to make sense by analogy to other bodily systems, eg cardiovascular and muscular; if not constantly stressed at a minimal level their ability to respond to occasional unusual stressors is compromised.
Jun 7, 2022·edited Jun 7, 2022Liked by Alasdair Munro
Fascinating writeup! Looking forward to more of your insight!
“Immunity debt” is a genius term!
Anecdotal of course, and I’m an adult, but I had three colds since February. The last one I’m currently recovering from. I typically get one cold per year and never one in JUNE.
"During the autumn and winter, the weather becomes colder driving social interactions indoors, and more humid which is a more efficient environment for transmission." In Maine, where I live, it is MUCH LESS humid in fall and winter.
Thank you so much for your insights. I look forward to your posts on Twitter. I have been fascinated by the shifts in viruses as well. I’m a pediatrician in southeastern United States. We experienced a huge wave during delta which was very scary because the adult beds were being taken up by delta and the ped’s beds by rsv.
I am more inclined to credit viral interference for the shift of the viruses:
1) the drop off in all other viruses happened prior to wide spread masking or social distancing. Excellent article by Dr. Christopher Harrison, infectious disease at UMKC (Kansas City, MO) which demonstrated every virus falling off early March except rhinovirus which he called the cockroach of viruses. 😂
2) most transmissions happen in the home setting. Therefore, the weather only plays a role via humidity and not personal behavior. Also, I’m in the south and we are a slovenly group who stays inside most of the time anyway!
This study has fascinated me because it is a retrospective study looking at how viruses interact and how they can shift the spread of other viruses. https://pubmed.ncbi.nlm.nih.gov/34968374/
I’m also personally doing a study of rsv/Covid in the outpatient setting. I’m looking at rapid antigen testing of those tested for rsv and Covid. So far, none are “co-infected.” I think the hospital numbers showing coinfection are skewed because they are often pcr. This may pick up an infection as far back as 6 weeks prior and doesn’t represent which is the cause of their hospitalization.
Thank you again for your work and your reasoned response during the pandemic.
Thank you! Fingers crossed for next winter’s flu season. I imagine the NHS is doing the same!
I’m glad to now know that term ‘immunity debt’. Very descriptive. Interesting and readable article for an average bear like me.
Very clear. But is it interesting that flu hasn’t ( yet) seen a resurgence ‘out of season’ too?
My two-year-old has had two colds, the nightmare-inducing norovirus, and a possible mild case of impetigo all since February.
I am 7-months pregnant and in Texas, awaiting 102F degree weather in the coming days. I’m not having a good time.
As not fun as this period has been, it helps to have an idea of what is going on and to hear from other people dealing with the same.
Thank you for a very clear post.
Your thesis seems to consider each virus - and immunity to it - in isolation and the downside of the reduced exposure is hence limited to the number of cases which might occur simultaneoulsy as the immune debt is "repaid", rather than the severities of infection which might be expected.
Do you think, however, that in fact low level constant exposure to infection (esp rhinoviruses and coronaviruses) might have non-specific priming effects on the innate immune system, such that depriving children of these might make them more susceptible to severe illnesses from RSV or influenza viruses?
This would seem to make sense by analogy to other bodily systems, eg cardiovascular and muscular; if not constantly stressed at a minimal level their ability to respond to occasional unusual stressors is compromised.
Fascinating writeup! Looking forward to more of your insight!
“Immunity debt” is a genius term!
Anecdotal of course, and I’m an adult, but I had three colds since February. The last one I’m currently recovering from. I typically get one cold per year and never one in JUNE.
That graph is Tokyo, not all Japan. You can find the data here (but you'll need a bit of Japanese to configure the chart)
https://survey.tmiph.metro.tokyo.lg.jp/epidinfo/weeklychart.do
If you look at 2022 and previous 5 years, you see that 2021 had a huge rebound and 2022 looks like it's back to perfectly normal again
https://photos.app.goo.gl/cVhUQ6hDyYCvaH227
"During the autumn and winter, the weather becomes colder driving social interactions indoors, and more humid which is a more efficient environment for transmission." In Maine, where I live, it is MUCH LESS humid in fall and winter.