[Irene]

Pfizer selected New Mexico, Rhode Island, Tennessee and Texas for their pilot delivery program "due to the states' immunization infrastructures, urban and rural variations, size and population diversity". First batches of vaccine will probably go to frontline medical workers first, followed by frail old people. a paper in Medrxiv favored "older first" model based on evolutionary game theory and mobility data, for largest decrease in mortality rates.

[smrk007]

Can I get a link to the Medarxiv paper? Would be an interesting read.

[Irene]

I was referring to this paper: https://www.medrxiv.org/content/medrxiv/early/2020/09/27/202...

[PandawanFr]

I am guessing this is the one: https://www.medrxiv.org/content/10.1101/2020.08.14.20175257v...

[splonk]

Pretty interesting paper, although I'm not sure it's the one OP was referring to. It's a pretty short paper with a whole pile of graphs at the end, so I encourage people to read it themselves. Quick notes from skimming:

- Treats it as an optimization problem for various levels of vaccine efficacy (10-100%), availability(10-100%), spread rate (R0 in {1.5, 2, 2.5, 3}), susceptibility to infection and symptomatic infection per age group.

- Four objective functions: symptomatic infections, deaths, non-ICU hospital usage at peak, and ICU usage at peak

- 5 age buckets: 0-19, 20-49, 50-64, 65-74, 75+

- Assumes 20% of population has immunity, and immunity lasts for a year.

- At higher efficacy and availability levels, there are some odd shifts to optimal vaccine distribution strategies. It's not strictly "oldest first" or "youngest first", there are some weird discontinuities in the middle buckets as well.

I had some questions about the wide 20-49 age bucket but it appears that it comes from a CDC planning scenario. It does look like that various curves start accelerating sharply past 50 or higher, so I guess treating the 20-49 group as one reasonably low risk group could be reasonable.

[Irene]

Yes, there could be many different scenarios; when vaccine supply is limited, vaccinate those at risk of death. BioNTech claims their vaccine efficacy is consistent across age groups, but we won't know for sure until large clinical trials are completed. Also, older people are less willing to be vaccinated earlier. More variables to include in the model...

[joaomacp]

From reading the abstract, that study comes to the interesting finding that with a highly effective vaccine, it is better to vaccinate the YOUNG first, to reduce the spread.

[pen2l]

What about... workers in the cafeteria who handle our food, cashiers at supermarkets and waiters who bring food over to you. I'm shocked most of the papers I'm reading don't mention these folks who are at the very intersection of our daily lives!

[splonk]

The paper assumes those people are vaccinated first, before the analysis for other age groups comes into play.

"Here, we consider that front-line health care workers and other essential personnel (e.g. firefighters, police) who should obviously be prioritized, have already been vaccinated."

[davak]

Probably too late for anybody's interest, but the risk of getting this from food is suspected to be incredibly low. Droplets being inhaled, entering through the eyes, or nasal mucous membranes are the likely real threats.

[vondur]

I guess that makes sense. The young seem to be the primary spreaders of the disease. Stop them, and then it slows the whole chain of infections. I can also see why they'd want to vaccinate the most vulnerable, if the young aren't really affected by the disease, it makes sense to skip them first. Conundrum I suppose.