Infectious Disease studies

Our researchers address the unique challenges of prevention, treatment, and outcomes of various infectious diseases. We conduct a number of clinical trials, vaccine-related studies, and examine a broad range of topics including hospital infections, antibiotic stewardship, environmental pathogens, influenza, hepatitis C. Studies have addressed the safety and efficacy of new hepatitis treatments, safety and effectiveness of the shingles vaccine; the safety of the quadrivalent human papillomavirus vaccine; testing and vaccination for hepatitis B, and uptake of childhood vaccinations.

A Multi-center, Retrospective Review of Invasive Aspergillosis Cases

A Multi-center, Retrospective Review of Invasive Aspergillosis Cases designed to primarily identify and collect data for a historical control of olorofim-treated patients, between 01 January 2010 and 31 March 2022.

Principal Investigator:

Emily Rayens, PhD

Funding Source:

Outcome Sciences, LLC an IQVIA Company

Funding Years:

2024

Research Categories:

A New Approach to an Old Problem: Redesigning Latent Tuberculosis Screening and Treatment

California has the highest incidence and largest number of tuberculosis (TB) cases in the contiguous U.S., of which 80% are due to reactivation. These TB cases can be prevented via screening and treatment of latent tuberculosis infection (LTBI), yet, current adoption of the latent TB screening and treatment guidelines has been extremely poor. We will leverage expansive electronic health record data from two of the largest healthcare organizations in California to create and validate a new LTBI screening and treatment approach that can vastly improve identification and successful treatment of LTBI.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

National Institute of Allergy and Infectious Diseases (NIAID)

Funding Years:

2020 - 2025

Research Categories:

A Retrospective Natural History Study of Coccifioidmycosis in California

Knowledge gaps exist regarding disease risk factors, presenting signs and symptoms, diagnostic approaches, and treatment for coccidiodomycosis infection. This study evaluates a large cohort of patients with community-acquired pneumonia in Southern California to assess cocci testing practices; additionally we evaluate a large cohort of patients diagnosed with cocci during 2011 to assess the natural history of infection.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Centers for Disease Control and Prevention (CDC)

Funding Years:

2014 - 2017

Research Categories:

A virtual network to investigate the clinical epidemiology of influenza and the effectiveness of influenza vaccines

The VISION Vaccine Effectiveness Network is a research collaboration between CDC, Westat, and multiple sites with integrated clinical, laboratory, and vaccination records in the United States that evaluate how well seasonal influenza (flu) vaccines protect people against flu, RSV vaccines protect people against RSV, and COVID-19 vaccines protect against COVID-19. VISION also assesses information on severe outcomes among people hospitalized with laboratory-confirmed flu and COVID-19 including intensive care unit (ICU) admission, invasive mechanical ventilation, and in-hospital death. These data help inform how well flu vaccines, RSV vaccines, and COVID-19 vaccines protect against severe outcomes.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Centers for Disease Control and Prevention (CDC)

Funding Years:

2023 - 2027

Antimicrobial resistant E. coli before and after California Senate bill 27 (ARES): a natural experiment

This study will allow us to comprehensively evaluate the casual link between food animal use of antibiotics, food product contamination, and human disease. These findings will inform future policy interventions towards a potentially modifiable source of AMR to reduce the burden on human populations nationally and globally.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

National Institutes of Health (NIH)

Funding Years:

2017 - 2023

Research Categories:

,

Burden of Chronic Hepatitis B Virus Infection and Linkage to Care in Southern California

The objective of this study is to describe the clinical management of patients with chronic HBV infection, how management practices vary by specialty, and the burden of severe complications due to HBV infection within a large pre-paid integrated healthcare system.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Gilead Sciences, Inc.

Funding Years:

2020 - 2022

Research Categories:

CDC/CFA Epidemiology Studies

The purpose of this project is to expand the Center for Forecasting and Outbreak Analytics’ (CFA) data network. CDC will have indirect access to medical records of patients via collaborative analysis to investigate trends and to detect, monitor, and characterize emerging infectious and non-infectious threats.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Centers for Disease Control and Prevention (CDC)

Funding Years:

2023 - 2028

Research Categories:

Comparison of vaccine effectiveness against hospitalization for influenza between cell-based and egg-based influenza vaccines

The proposed study aims to compare the vaccine effectiveness (VE) against hospitalization for influenza between Flucelvax Quadrivalent and egg-based influenza vaccines used in Kaiser Permanente Southern California (KPSC) during the 2017-2018 season.

Principal Investigator:

Hung Fu Tseng, PhD, MPH

Funding Source:

Seqirus, Inc.

Funding Years:

2018 - 2019

COVID-19 Sample-Swab Collection Study

Collect positive SARS-CoV-2 specimens and conduct sequencing to identify variant types.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Pfizer, Inc.

Funding Years:

2021 - 2024

Research Categories:

,

Development and application of a smartphone-based data collection method for adverse events following SARS-CoV-2 vaccination in the Vaccine Safety Datalink

The proposed project will involve designing, piloting, evaluating, and expanding an SMS- and web-based Vaccine Safety Monitoring (VSM) system.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Centers for Disease Control and Prevention (CDC)

Funding Years:

2021 - 2024

Development of a Clinical Risk Tools to Predict Antibiotic Resistance and Treatment Failure/Hospitalizations among Adult, Hospitalized Patients with complicated Urinary Tract Infections (cUTIs) in the Outpatient Setting

The major goal of this project is to characterize and estimate the probability of antibiotic resistance among adult patients with complicated urinary tract infections (cUTIs) in the outpatient setting, as well as characterize cUTI patients who are at risk for treatment failure.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

SPERO, Inc.

Funding Years:

2021 - 2023

Do inpatient antimicrobial stewardship programs help us in the battle against antimicrobial resistance?

We propose to conduct a comprehensive analysis of the impact of ASPs on relevant clinical outcomes in a large integrated health care system. Specifically, we will evaluate the changes in consumption of targeted ASP drugs pre- and post-ASP and the changes in inpatient infection rates with clinically important drug-resistant organisms (DROs) pre- and post-ASP.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Not Applicable

Funding Years:

2017 - 2021

Research Categories:

Economic, Epidemiologic and Clinical Burden Associated with Neutropenia and Febrile Neutropenia in Three Cancers

The primary objective of this study is to estimate the resource utilization and direct medical expenditure associated with neutropenia and febrile neutropenia, in Non-Hodgkin’s Lymphoma, Breast cancer and Lung cancer patients. The secondary objective is to determine the trend of incidence of neutropenia with and without fever in Non-Hodgkin’s Lymphoma, Breast cancer and Lung cancer. The study will also describe management patterns and evaluate trend of management patterns for febrile neutropenia. Lastly, we will also estimate the febrile neutropenia specific mortality rate in hospitalized patients by cancer type.

Principal Investigator:

Aniket A. Kawatkar, PhD, MS

Funding Source:

Amgen, Inc.

Funding Years:

2011 - 2015

Effectiveness and Safety of Recombinant Zoster Vaccine (RZV) in Patients with Psoriasis (PsO) or Psoriatic Arthritis (PsA)

The vaccine effectiveness (VE) objectives are to estimate the VE of at least one RZV dose in preventing herpes zoster (HZ) in adults>=18 years of age with psoriasis (PsO) and psoriatic arthritis (PsA). The safety objectives are to assess the number of incident flare cases within 30 days following any RZV vaccination as compared to the risk in self-controlled comparison periods, in adults>=18 years of age with PsO and PsA.

Principal Investigator:

Hung Fu Tseng, PhD, MPH

Funding Source:

GlaxoSmithKline, LLC

Funding Years:

2022 - 2028

Effectiveness of pneumococcal conjugate vaccine against severe clinical outcomes of coronavirus disease 2019 (COVID-19) among adults: a cohort study

The objectives of this study were to assess the effectiveness of PCV13 against severe COVID-19 outcomes and to assess the burden of PCV13-preventable illness attributable to COVID-19.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Pfizer, Inc.

Funding Years:

2020 - 2021

Effectiveness of pneumococcal vaccination (20vPnC) to prevent all-cause pneumonia and lower respiratory tract infections among adults>=18 years old with an increased risk of pneumococcal disease at Kaiser Permanente Southern California

Pneumonia accounts for a substantial burden of morbidity and mortality among adults. Assessing the effectiveness of 20vPnC against all-cause pneumonia is critical to estimating the public health benefits of 20vPnC use among United States (US) adults in. These data may be used to guide implementation and use of pneumococcal conjugate vaccine (PnCs) among adults. While the 13vPnC estimates of vaccine effectiveness (VE) against all-cause outcomes were lower than those against vaccine-type (VT) outcomes, the actual impact of PnC against all-cause outcomes could be considerably greater than that estimated from VT outcomes.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Pfizer, Inc.

Funding Years:

2023 - 2025

Enhancing Outbreak Analytics and Forecasting with Electronic Health Records

Our overall objective with this supplement is to estimate incidence, prevalence, and natural history parameters of three emerging or re-emerging disease threats in Southern California—influenza A H5N1, dengue, and mpox—to support the modeling community and public health decisionmakers. We will collect remnant samples from KP members from clinical care and test/analyze them accordingly.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Centers for Disease Control and Prevention (CDC)

Funding Years:

2024 - 2028

Research Categories:

Enhancing outbreak analytics and forecasting with electronic health records

This study aims to create a more effective method of modeling infectious diseases that addresses limitations learned as a result of the COVID-19 pandemic and its public health impact. Its methods adapt and create modeling and data integration methods, software, clinical data, and training to achieve this goal. This includes addressing multiple challenges such as sharing and coordinating data access, increasing access understanding of machine learning (ML), understanding the true patterns of disease transmission, having a sample to represent all infections and timelines, and reducing the gap between transmission and diagnosis. Through multiple strategies, this study will provide a more comprehensive approach to data modeling in an effort to prepare for future outbreaks.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Centers for Disease Control and Prevention (CDC)

Funding Years:

2023 - 2028

Research Categories:

,

Epidemiology of recurrent urinary tract infections among adults in an integrated health care organization in the United States

This study will examine the epidemiology of rUTI among adults ages =18 years in a large, diverse integrated care organization in the US.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

GlaxoSmithKline, LLC

Funding Years:

2021 - 2023

Research Categories:

Evaluating Influenza and COVID-19 Vaccine Effectiveness in Preventing Laboratory Confirmed Illness in a Southern California Population

The current study proposes to evaluate the VE for influenza as well as the VE for COVID-19 both before and after the flu season as well as concurrently with influenza.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Centers for Disease Control and Prevention (CDC)

Funding Years:

2021 - 2023

Feasibility Assessment prior to conducting a BNT162b2 Vaccine Effectiveness case-control study at Kaiser Permanente Southern California

The objectives of this large retrospective data-only study are to use two parallel study designs to assess the VE of Pfizer COVID-19 vaccine against 2 primary endpoints: 1.) Severe outcomes (COVID-19 associated hospitalization, ICU admission, and death); and 2.) Outpatient laboratory-confirmed COVID-19 diagnosis.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Pfizer, Inc.

Funding Years:

2020 - 2024

Feasibility Assessment prior to conducting an RSVpreF Vaccine Effectiveness study at Kaiser Permanente Southern California among Older Adults

Respiratory Syncytial Virus (RSV) is a major cause of respiratory infection for infants and older adults. In this study, we will estimate vaccine effectiveness of Pfizer’s RSVpreF vaccine against RSV-related lower respiratory tract infection requiring hospitalization among KPSC older adults who are eligible for vaccination per current ACIP recommendations.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Pfizer, Inc.

Funding Years:

2023 - 2024

GWU/Wellcome 1 Feasibility

To collect preliminary data to support the larger Wellcome grant.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

The George Washington University

Funding Years:

2018 - 2022

HIV Status and Incidence and Outcomes of Heart Failure

The overall goal of this study is to identify optimal treatment strategies to reduce the impact of cardiovascular disease complications in HIV-infected patients, focusing on the understudied diagnosis of heart failure

Site Principal Investigator:

Kristi Reynolds, PhD, MPH

Funding Source:

National Heart, Lung, and Blood Institute (NHLBI)

Funding Years:

2016 - 2020

Identification of risk factors for resistant Pseudomonas aeruginosa infections with or without ESBL among hospitalized patients and developments and validation of a risk predictive tool

This study aims to develop a clinical risk prediction tool for antibiotic resistant Pseudomonas infections among inpatients.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Merck & Co., Inc.

Funding Years:

2016 - 2019

Research Categories:

Impact of nirmatrelvir-ritonavir on changes in healthcare utilization and frailty following COVID-19: a difference-in-difference analysis

The study aims to estimate the impact of nirmatrelvir-ritonavir on changes in healthcare utilization and frailty following COVID-19. We will use a difference-in-difference design to compare the changes before and after COVID-19 between those who did and did not receive nirmatrelvir-ritonavir.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Pfizer, Inc.

Funding Years:

2024 - 2025

Impact of the introduction of the Recombinant Zoster Vaccine (RZV) on clinical outcomes and payer budgets over a short-to-intermediate horizon- HO-17-18378

To better understand the short-term impact of the introduction of RZV on clinical outcomes and payer budgets, GSK has developed a US-specific budget impact model that is utilized as a flexible tool for different types of US population-based decision makers. The model can be customized to reflect the patient population information and outcomes associated with RZV vaccination scenarios. We will describe the demographics, epidemiology, and health care utilization associated with herpes zoster in the KPSC population. This information will contribute to the inputs for the budget impact model.

Principal Investigator:

Hung Fu Tseng, PhD, MPH

Funding Source:

GlaxoSmithKline, LLC

Funding Years:

2018 - 2019

Kaiser Permanente Southern California and Novavax Collaboration on RSV Epidemiology

The purpose of this study is to provide critical information about the predictors of severe RSV disease, describe epidemiology and burden of hospitalized RSV disease in older adults, and assess healthcare utilization associated with hospitalized RSV disease in older adults in a community setting. A population of hospitalized older adults testing positive for influenza will also be identified for comparison purposes.

Principal Investigator:

Hung Fu Tseng, PhD, MPH

Funding Source:

Novavax, Inc.

Funding Years:

2016 - 2018

Kidney Function Decline in Patients with CKD and Untreated Hepatitis C Infection

Studies evaluating the role of hepatitis C viral (HCV) infection on the progression of CKD are few and conflicting. Therefore, we evaluated the association of untreated HCV on kidney function decline in patients with stage 3-5 CKD.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Merck & Co., Inc.

Funding Years:

2014 - 2017

Research Categories:

,

Learning from California Senate bill 27: a natural experiment

This study complements an ongoing R01 study to provide more compelling evidence regarding the impact of SB27 by examining all major meat types (chicken, turkey, pork and beef) that may be impacted by the bill. Likewise, we include collection of the frank foodborne pathogens, Salmonella and Campylobacter, to provide additional insights into the potential effectiveness of this policy intervention.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Wellcome Trust

Funding Years:

2018 - 2023

Non-interventional study to estimate the effectiveness of Arexvy vaccine in preventing respiratory syncytial virus-associated lower respiratory tract disease hospitalization in adults>=60 years: a test negative design

This observational study aims to assess the vaccine effectiveness of Arexvy in preventing laboratory-confirmed RSV-acute respiratory infection (ARI)/LRTD hospitalization in adults>=60 years at Kaiser Permanente Southern California, using a test-negative design.

Principal Investigator:

Hung Fu Tseng, PhD, MPH

Funding Source:

GlaxoSmithKline, LLC

Funding Years:

2023 - 2029

Outpatient Clostridioides difficile Feasibility Study

The overall goal of this feasibility work will be to develop a protocol for the main outpatient C. difficile study that will achieve the goals of the retrospective, prospective, and validation components outlined by the funder.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Pfizer, Inc.

Funding Years:

2021 - 2023

Pfizer COVID-19 BNT162b2 Vaccine Effectiveness Study

Collect positive SARS-CoV-2 specimens and conduct sequencing to identify variant types.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Pfizer, Inc.

Funding Years:

2021 - 2024

Real World Evidence of Paxlovid at Kaiser Permanente Southern California

This project will describe characteristics associated with prescribing and dispensing of individuals receiving Paxlovid and not receiving Paxlovid among SARS-CoV-2 positive individuals.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Pfizer, Inc.

Funding Years:

2022 - 2024

Real-World Study of the Comparative Effectiveness of Licensed Influenza Vaccines in Preventing Hospitalizations with Influenza in the 2022-2023 Influenza Season

Comparative vaccine effectiveness of influenza vaccine in the 2022-2023 season.

Principal Investigator:

Hung Fu Tseng, PhD, MPH

Funding Source:

ModernaTX, Inc.

Funding Years:

2023 - 2025

Surveillance for invasive pneumococcal disease and otitis media among Kaiser Permanente Southern California Membership from 2020 through 2027

This project will describe characteristics of invasive pneumococcal disease (IPD) and otitis media (OM) cases by demographics (including socioecological characteristics), history of vaccination with conjugated pneumococcal vaccine (number of doses and dates) clinical characteristics, and outcomes, overall and by age and ACIP-defined risk groups.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Pfizer, Inc.

Funding Years:

2022 - 2027

The association between Cesarean Delivery, Labor and Body Weight in Children.

This project is part of a series of CDC studies to better understand the association between birth factors such as delivery mode labor or rupture of membrane, and exposure to intrapartum antibiotics and childhood weight gain.

Principal Investigator:

Corinna Koebnick, PhD, MSc

Funding Source:

Centers for Disease Control and Prevention (CDC)

Funding Years:

2019 - 2022

Understanding and supporting COVID-19 vaccine confidence among health care providers

The purpose of this mixed-methods study is to examine perceptions of COVID-19 vaccines among health care providers, willingness to receive and recommend COVID-19 vaccine, drivers of vaccine hesitancy, and needs for tailored interventions to support confidence in COVID-19 vaccines among health care providers and community members.

Funding Source:

Kaiser Permanente

Funding Years:

2021

Utilizing Real World Data to Describe Clinical and Safety Outcomes Among Hospitalized COVID-19 Patients, and to Create a Comparator Arm for a Randomized Controlled Trial Evaluating the Efficacy and Safety of Actemra for COVID-19 Patients

Elevated tissue and serum levels of IL-6 have been implicated in the disease pathology of several inflammatory and autoimmune disorders including rheumatoid arthritis, systemic juvenile idiopathic arthritis (sJIA), and cytokine-release syndrome (CRS). Tocilizumab or TCZ (Actemra) is a recombinant humanized, anti-human monoclonal antibody directed against soluble and membrane-bound IL-6R. On March 3rd 2020, TCZ was included in the updated diagnosis and treatment plan for COVID-19 issued by the China National Health Commission as one treatment option for severe or critical forms of COVID-19 pneumonia. However, despite fairly widespread use in China, Actemra has not received health authority approval for COVID-19 in any country. More robust clinical evidence regarding the safety or efficacy of TCZ in the treatment of COVID-19 is needed. Roche is conducting a Phase 3, randomized, double-blind, placebo-controlled, multicenter study to assess the efficacy and safety of TCZ in combination with SOC compared with matching placebo in combination with SOC in hospitalized adult patients with severe COVID-19 pneumonia (n=330). KPSC is collecting demographic, comorbidity, and clinical information on KPSC patients hospitalized with COVID-19 infection to create a real world data (RWD) comparator arm that will be matched to the TCZ treatment arm of the RCT.

Principal Investigator:

Sara Yee Tartof, PhD, MPH

Funding Source:

Genentech, Inc.

Funding Years:

2020 - 2022

Zoster Vaccine and Risk Factors of Zoster and Post-Herpetic Neuralgia

The aims of the study are to determine the incidence of reactivation of Oka strain VZV in community-dwelling persons vaccinated with zoster vaccines; to test clinical isolates for evidence of recombination between vaccine and wild-type strains VZV; to identify risk factors of HZ among individuals vaccinated with zoster vaccines; to identify risk factors for post-herpetic neuralgia (PHN) among HZ cases who were either vaccinated or unvaccinated with zoster vaccines, and to compare the clinical manifestations and risk of PHN between vaccinated and unvaccinated individuals.

Principal Investigator:

Hung Fu Tseng, PhD, MPH

Funding Source:

National Institute of Allergy and Infectious Diseases (NIAID)

Funding Years:

2011 - 2017