---
# System prepended metadata

title: Model-informed COVID-19 vaccine prioritization strategies by age and serostatus
tags: [articles]

---

# Model-informed COVID-19 vaccine prioritization strategies by age and serostatus

###### tags: `articles`
[Note of Shen(2022/3/2)](https://hackmd.io/NJRqEdYvQ-mKCSF3914P7w?both)

## Introduction

Compare the impact of different COVID-19 vaccine prioritization strategies 
<!--- 
with variation in 3 areas

Variations:
1. Variation in performance of the vaccine (vaccine efficacy)
2. Variation in infection and fatality rate by age
3. Variation in age distribution, age stratified contact rate.
--->

There are two main approaches to vaccine prioritization:
1. vaccinate those at highest risk for severe outcomes
2. vaccinate those who do the most transmitting

## Details of the Model

- SEIR model: [Supplement material](https://hackmd.io/@xxoooxx345678/Syo2iyDxK)

- Input
    - **strategy**
    - age-dependent contact matrix
    - susceptibility to infection rate
    - infection fatality rate
    - infectious period
    - latent period
    - $R_0$
    - vaccine efficacy
    - ...
- Output (Performance of the strategy)
    - cumulative incidence of infections
    - mortality
    - years of life lost (YLL)

## Impacts of vaccine prioritization strategies on mortality and infectious 

`Vaccines with 90% efficacy, 0.2% rollout/day`

- Prioritizations
    1. under 20
    2. adults between ages $20$ and $49$ years
    3. adults $20$ years or older
    4. adults $60$ years old or older
    5. all individuals 

![](https://i.imgur.com/vwEqAGO.png)

Scenario 1: $R_0=1.15$
Scenario 2: $R_0=1.5$
![](https://i.imgur.com/j9cJKLN.png)


## Impact of transmission rates, age demographics, and contact structure

`Vaccines with 90% efficacy`

![](https://i.imgur.com/6rNOhw5.png)

## Variation in vaccine efficacy by age

![](https://i.imgur.com/wExHLYO.png)

scenario 1: $R_0=1.15$
scenario 2: $R_0=1.5$

![](https://i.imgur.com/RupMEDK.png)

## Incorporation of population seroprevalence and individual serological testing

`Vaccines with 90% efficacy, 0.2% rollout/day`
$R_0=1.5$

![](https://i.imgur.com/ueGHn3k.png)

## Supplement

### More Complicated Model

Considering
- vaccine hesitancy
- pre-transmission rollout
- variable rollout rate
- imperfect serological tests
- ...

### Impact of vaccine efficacy

scenario 1: 0.2% rollout/day, $R_0=1.15$
scenario 2: 0.2% rollout/day, $R_0=1.5$
scenario 3: pre-transmission vaccination, $R_0=1.5$
scenario 4: pre-transmission vaccination, $R_0=2.6$

> $R_0$ of the delta variant is 5~8

![](https://i.imgur.com/I7XdGrd.png)

### Impact of rollout speed

![](https://i.imgur.com/lu6dsLg.png)



