BETA version This website is currently under construction. Results are in development and should not be considered final or used to support decision making.

Implications of management actions

This page highlights the results of various levels of vaccinations administered daily, given a selected set of assumptions of virus and vaccine parameters.

Predicted outcomes


Placeholder text
BETA version This website is currently under construction. Results are in development and should not be considered final or used to support decision making.

Implications of management actions

This page highlights the results of various levels of vaccinations administered daily, given a selected set of assumptions of virus and vaccine parameters.

Predicted outcomes

Management option A
Management option B
Management option C
Management option D

Placeholder text
BETA version This website is currently under construction. Results are in development and should not be considered final or used to support decision making.

Current situation (no variant)

In our most basic scenario, we assume that the vaccine efficacy as measured in clinical trials and transmissability of SARS-CoV-2 as measured throughout 2020 will be largely unchanged in the near future.


Vaccine effectiveness and new strain estimates

Parameter Value
Stopping infection (susceptibility) 80%
Stopping symptomatic infection 95%
Stopping infectiousness 10%
New strain rate of import 0 case per day
New strain transmissability 1x original strain
BETA version This website is currently under construction. Results are in development and should not be considered final or used to support decision making.

Plausible pessimistic (UK variant)

Strain B.1.1.7 leads to a moderate drop in efficacy. It is likely that within weeks the predominant strain the predominant strain will be the UK variant (B.1.1.7) which is thought to be both more transmissable, and more resistant to the current vaccines.


Vaccine effectiveness and new strain estimates

Parameter Value
Stopping infection (susceptibility) 70%
Stopping symptomatic infection 86%
Stopping infectiousness 10%
New strain rate of import 1 case per day
New strain transmissability 1.5x original strain
BETA version This website is currently under construction. Results are in development and should not be considered final or used to support decision making.

Worst case (SA variant)

Strain B.1.351 leads to a significant drop in efficacy. Perhaps even more worrisome than the UK variant is the South African Variant (B.1.351). If that were to become the predominant strain, then vaccine efficacy would drop even further.


Vaccine effectiveness and new strain estimates

Parameter Value
Stopping infection (susceptibility) 50%
Stopping symptomatic infection 60%
Stopping infectiousness 5%
New strain rate of import 1 case per day
New strain transmissability 1.5x original strain
BETA version This website is currently under construction. Results are in development and should not be considered final or used to support decision making.

Best case new variant

The best case scenario. Even with a new strain emerging, vaccine efficacy remains high.


Vaccine effectiveness and new strain estimates

Parameter Value
Stopping infection (susceptibility) 95%
Stopping symptomatic infection 95%
Stopping infectiousness 100%
New strain rate of import 1 case per day
New strain transmissability 1.5x original strain

King County COVID-19 Modeling Group

We are an academic group led by Fred Hutchinson Cancer Research center researchers. We are funded by the CTSE and the NIH.

Our work is dedicated to modeling the ongoing SARS-CoV-2 pandemic, with a particular focus on matching and projecting local data from King County Washington, USA.

The model considers the epidemiology of COVID-19 including social distancing, vaccination, and emerging variants.





This website was created by

Eileen Burns (Independent)

Chloe Bracis (Grenoble)

David Swan (Fred Hutch)

Mia Moore (Fred Hutch)

Daniel Reeves (Fred Hutch)

Dobromir Dimitrov (Fred Hutch/UW)

Joshua Schiffer (Fred Hutch/UW)

COVID-19 Epidemiological model

We have developed a mechanistic mathematical model to describe the epidemiological dynamics of COVID-19 since March 2020.

Model fitting is detailed here (link to be added).

Mathematical details are presented here (link to be added).