1/I've been reflecting on this thread for a bit.

I have zero intention to be unkind to David here, rather it is an opportunity to touch base on the current state of social media/pubic discourse & our current trajectory (extending well beyond COVID).

Summary: Vey iz mir

🧵

https://twitter.com/DFisman/status/1616079629277601793

2/ Just to appreciate where I'm coming from here:

I work at the intersection of clinical infectious diseases, epidemiology, public health & policy

I know this realm well & can spot bullshit 20 miles out

I aim to be data-focused & apolitical

I still screw up from time to time

Based on existing data to date:

1. Current covid vaccines continue to excel at preventing severe infection.

2. Vaccination provides decent protection VS infection (& transmission) but wanes considerably at ~2 months...not to 0%, there is still some protection. 🧵 3. The current (ancestral) vaccine provided strong protection VS infection/transmission to the ancestral virus (& Alpha, & to some extent Delta). Unfortunately Omicron is a bit different.

4. While we obviously don't want people to get infected, hybrid immunity is real & helpful.

1/ Several important points on the monkeypox outbreak by Dr. Ghebreyesus:

"This is an outbreak that can be stopped, if countries, communities & individuals inform themselves, take the risks seriously & take the steps needed to stop transmission & protect vulnerable groups." 2/ "The focus for all countries must be engaging & empowering communities of men who have sex with men to reduce the risk of infection and onward transmission, to provide care for those infected, and to safeguard human rights and dignity."

🙂

1/ There are many people & communities who would benefit from a 3rd COVID vaccine dose but have not received one (doses 1, 2, & 4 too).

There is also more emerging data demonstrating how 2 vaccine doses PLUS infection is as good as 3 doses in preventing severe COVID infection. 2/ "Two-dose effectiveness against hospitalization among previously-infected individuals did not wane across 11 months and did not significantly differ from three-dose effectiveness despite longer follow-up..."

bit.ly/3OUP44j preprint by Dr. S. Carazo et al.

1/ Long COVID is real & can be debilitating.

But in some positive news, chronic symptoms of COVID in those under 18 is less common than initially thought (0.8%) & most have symptom resolution in 5 months.

This is a big study (>32K) including a control group.

Very helpful. 2/

Link to study: bit.ly/3Gf9vn4

Authors: Luise Borch, Mette Holm, Maria Knudsen, Svend Ellermann-Eriksen & Soeren Hagstroem

George Carlin listed "7 words you can't say on TV".

Similarly, there are covid-related words/phrases you can't discuss on Twitter without triggering an outpouring of polarized responses.

Just FYI, back on planet earth, we discuss these concepts frequently.

🧵👇 Several words/phrases are "weaponized" to overplay or underplay the significance of covid in various scenarios...it's an obvious problem.

Still, these are important terms/concepts that warrant objective study & discussion without value judgment.

A few examples 👇

1/ Mobile phone microscopes may soon facilitate screening & treatment programs for parasitic infections in low-resource settings.

They are low-cost, portable & easy to use at the point-of-care.

Dr. Jean Coulibaly (Côte d'Ivoire) leading the way, stamping out schistosomiasis 👇 2/ Mobile phone microscopes: bit.ly/3kwkhxg

This collaboration is led by Drs. Jean Coulibaly & Kigbafori Silué (Côte d'Ivoire), Dr. Richard Ephraim (Ghana), Prof Dan Fletcher & engineering team @Cal_Engineer, @StanfordMed, @SwissTPH, @uoftmedicine, @UHN

Video 👇

1/ It's pretty clear we need to expand #COVID19 3rd doses.

Vaccine effectiveness is still ⬆️protective against severe illness. There is evidence for waning VS infection.

Some want to give out 3rd doses like Halloween candy, others think it ends at 2. As always, details matter.

https://twitter.com/BogochIsaac/status/1446120626654044164

2/ A few thoughts:

-Some need 3rd doses now, but we all don't need 3rd doses now (see further below).

-Longer duration from last dose = higher prob of infection.

-Spacing out dose 1 & 2 (not done in USA/Israel) likely provides more robust protection.

bbc.in/3uWnXfA

A few semi-related #COVID19 thoughts:

1. The virus isn't going anywhere any time soon

2. We will all be exposed at some point, maybe not today or this month, but in the next year or two

3. Must continue to⬆️the # of people with antibodies (from vaccination) prior to exposure👇 4. The pandemic is not over, even in countries with +++ vaccine access. Mitigation efforts are still needed to protect the vulnerable & unvaccinated (eg ineligible, those with barriers, etc) & to prevent overwhelming the healthcare system.

(The pandemic will end, just not yet)👇

1/ Moderna's #COVID19 vaccine was approved for use in 12-17 year olds in Canada.

I am a firm believer in COVID-19 vaccines, including for this age cohort.

NACI has a statement that is worth reading.
1. Summary: bit.ly/3mFuERq
2. Whole Megillah: bit.ly/38q2KQJ 2/ Informed decision making is always key.

People need to know the benefits, risks, alternatives, & context when making a medical decision.

NACI describes a greater risk of myocarditis with Moderna vs Pfizer, typically in younger male cohorts. Most are mild & recover quickly.👇

1. ~80% of eligible Canadians have received a 1st dose of a #COVID19 vaccine & 2nd doses coming in fast. Nice!

2. This still leaves millions unvaccinated.

3. Delta (& all COVID) is +++ contagious, so no surprises when non-vax people get infected as measures lift (eg Europe).
👇 4. While #COVID19 vaccines work extraordinarily well, there are enough unvaccinated folks who could get sick & require medical care.

5. Even if we see lower overall COVID-related healthcare usage due to significant vaccine uptake, we can't ignore pressure on healthcare system.👇

In an era where good news is in short supply, this analysis from Public Health England suggests that both Pfizer & AstraZeneca are highly effective against hospitalization with the Delta variant (after 2 doses):

1. Pfizer: 96%
2. AstraZeneca: 92%

Link: bit.ly/3iBSsn7 More details of the analysis can be found at this link, with effectiveness of Pfizer & AstraZeneca vs Alpha & Delta variants: bit.ly/3gv0uLX

More emerging data from England regarding the Delta variant (B.1.617, initially discovered in India):

-It is more transmissible
-Appears to cause more significant illness

**Vaccines are still effective but 2 doses are ++ more protective than 1**

Link: bit.ly/3vPg2R4 The takeaways are pretty clear- we need to vaccinate quickly with smart 1&2 dose strategy focusing on vulnerable individuals & communities.

Unvaccinated & undervaccinated pockets (barriers to care, choice, etc) will be vulnerable and see spikes.

But polls show most🇨🇦to be vaxed

It looks like Canada's National Advisory Committee on Immunization (NACI) will give the green light to mixing & matching #COVID19 vaccines.

For example, those with a 1st dose of AstraZeneca may choose a 2nd dose of AZ or an mRNA vaccine.

bit.ly/3i7xkot by @adamsmiller Mixing & matching #COVID19 vaccines may:

1. Provide more options to Canadians

2. Facilitate vaccine rollout if there are supply issues with a particular product

3. Possibly speed up rollout

1/ A few #COVID19 vaccine updates for Ontario:

The province will receive 250K doses of AstraZeneca this month, likely reserved for 2nd doses.

Also, it is likely that those who received 1st dose of AZ *may* get a 2nd dose of an mRNA vaccine.

(Photography: Jay Kerr @bombippy) 2/ The push for vaccine equity by pouring vaccines into 114 heavily impacted postal codes was largely successful (to date), with a higher proportion of people receiving a 1st dose in those areas compared to other neighborhoods.

Good news, but the job isn't done.

Ontario is pausing 1st doses of AstraZenca vaccine today as per Dr. David Williams, the Chief Medical Officer of Health,

He cites:
1. Risk of thrombosis
2. Greater supply of mRNA vaccines

Those with 1st dose of AZ will either get a 2nd dose of AZ or perhaps an mRNA vaccine. They cite the risk of blood clots (aka VITT*) as ~1:60000, based on Ontario data.

*vaccine-induced immune thrombotic thrombocytopenia

1/ Ontario #COVID19 vaccine update (Take 2 - after twitter hack/drama):

Ontario has vaccinated >130000 people per day May 4, 5 & on track for this today too.

Over 40% of adults in the province have received at least 1 dose.

Some details on past few days & next few weeks 👇 2/ We doled out a ton of AstraZeneca when eligibility dropped from 55 to 40 yrs, but then ⬇️ supply led to ⬇️ pace of AZ vaccination.

Currently there is very little AZ administered this week following recent public discourse.

I am happy for those who received this vaccine.

1/ A few #COVID19 vaccine updates for Ontario:

The pace of vaccination is picking up again.

>130000 vaccines were administered May 4, and >133000 today so far.

>40% of adults in ON have received a 1st dose.

Some thoughts about the past & future weeks👇 2/ People came out in droves for AstraZeneca when the age limit dropped to 40. We had a lot of AZ in the freezer at that time & now there is not much left.

(Much has been said about AZ since then. I am happy for people who received it)

https://twitter.com/BogochIsaac/status/1389353158078521346?s=20

1. "Health Minister Patty Hajdu says her government embraces the concept of 'vaccine passports' & will come up with a form of certification to allow vaccinated Canadians to travel internationally."

Smart move & good to be proactive.

bit.ly/3eNTusr by @peterzimonjic 2/ There are a growing number of countries requiring proof of #COVID19 vaccination for travel...18 are currently listed here.

Also the EU just announced they would be open to vaccinated travellers from the USA this summer.

bit.ly/336woIo

1/ A few points to clarify a few points...

These vaccines are really really good, but not perfect.

One dose of a vaccine provides excellent protection against #COVID19 infection, but of course 2 doses provide more protection.

https://twitter.com/drmwarner/status/1387420736202149889

2/ NACI outlines protection after 1 dose of a vaccine in their recent document:

"Most importantly, these studies show one dose of the Pfizer-BioNTech & AstraZeneca vaccines are
approximately 80% effective against hospitalization..."

Details: tinyurl.com/saby9kma

1. Ontario administered >125000 vaccines today. 2. Todays ~125K is not the final count, there are still a couple of hours left.

Yesterday ON vaccinated ~134K (that's 0.91% of ON population in a day).

By comparison, yesterday the USA vaccinated ~3.1 million (0.94% of USA population in a day).

We are catching up.