2021-10-29 10:18:58

Presentation overview

Modeling SARS-CoV-2 on a university campus

Motivation

  • We wanted to know if/how one could safely re-open college campuses.
  • Emory University approached my colleague Ben Lopman. We built a somewhat general model.

Methods

  • Simulation model for COVID-19 spread and screening/testing based control.

Results

Acknowledgments and More Information

COVID-19 infection among close contacts of index patients

Motivation

  • Does the severity of COVID infection in an index case impact COVID outcomes in infected contacts?

Methods

Results

Acknowledgments and More Information

  • Collaborators: Yang Ge, Leonardo Martinez, Shengzhi Sun, Zhiping Chen, Feng Zhang, Fangyu Li, Wanwan Sun, Enfu Chen, Jinren Pan, Changwei Li, Jimin Sun, Feng Ling, Ye Shen.
  • More information: https://doi.org/10.1001/jamainternmed.2021.4686

Modeling the impact of social distancing, contact tracing, and case isolation on COVID-19 spread

Motivation

  • Use a model, calibrated to COVID-19 case data, to determine the effectiveness of social distancing, contact tracing, and case isolation.

Methods

Results

Results

CNT = level of social contacts

CNT = level of social contacts

Acknowledgments and More Information

Assessing the impact of dose for influenza vaccines

Introduction

  • Inoculum dose is an important determinant of infection and vaccination outcomes.
  • For infection, higher dose is often associated with greater risk of infection (ID50) and more severe outcomes (LD50).
  • For vaccines, dose is thought to impact both immunogenicity/efficacy and side effects (morbidity).

Important considerations I

  • Trade-offs between availability/safety and efficacy likely exist.
  • Impact of dose on vaccine efficacy might not be monotone.

Important considerations II

  • Impact of dose on homologous or heterologous protection might not be monotone.

Vaccine dose choice in practice

  • A few doses are explored in phase 1 and 2 trials.
  • Based on those data, one of the doses is chosen for phase 3 trials (and beyond) in a non-rigorous manner.

Claim: Knowing in more detail how dose impacts host response following vaccination might help optimize vaccines.

Present study setup

  • Open cohort of individuals who were vaccinated (some repeatedly) during the 2014/15 - 2018/19 flu seasons.
  • The default vaccine was the trivalent or quadrivalent standard dose (SD, 15µg) Fluzone vaccine.
  • Individuals >=65 years were offered the high-dose (HD, 60µg) trivalent vaccine.
  • We evaluated immune response following vaccination, specifically antibodies as measured by hemagglutination inhibition assay (HAI).

Question: What is the impact of standard dose (SD) versus high dose (HD) vaccine on HAI antibodies?

Study population

“Raw” data - homologous responses

“Raw” data - heterologous responses