Does COVID Increase Your Risk for Later Infections?

If you suffered and recovered from COVID in the past few years, you might wonder if it increases your risk of other infections. Patients are asking their physicians and other health care providers this question a lot lately. 

Last winter’s flu season arrived early in the United States, did COVID play a part in its timing? Respiratory Syncytial Virus (RSV) led to record numbers of hospitalizations of children last winter, and Streptococcal infections surged in the United Kingdom, U.S., and elsewhere. People want to know if there’s a link between COVID and these other diseases.

COVID is linked to some subsequent infections, but we need to learn a great deal more about the relationships between COVID and others.  Here is what we know about various infections that can follow or arise during COVID:

Bacterial Pneumonia & Superinfections

The link between COVID illness and later infections is well established for bacterial pneumonia arising during an acute COVID viral illness. Healthcare workers call this phenomenon a “superinfection.”

Superinfections are common with COVID infections. In hospitals, physicians regularly confirm bacterial pneumonia in the days and weeks following an admission for COVID disease. Patients then require antibiotics to treat these secondary infections. 

COVID isn’t the only illness with links to superinfections. Influenza or RSV often create an environment for additional infections. A large percentage of deaths during the infamous 1918 influenza pandemic were from Strep pneumonia that arose days after the initial influenza viral infection. In 1918, antibiotics were not available, so many who made it through the influenza virus onslaught then did not survive the secondary bacterial superinfection.

Influenza and RSV

Last winter’s flu season arrived months early in the U.S., catching many by surprise and infecting many before vaccines were widely deployed. Around the same time, RSV, which causes “croup” and related respiratory illness in children, was filling pediatric units in hospitals in the U.S. and elsewhere. RSV has the potential to be fatal in children and in the elderly, who were also impacted. 

These events drove the question – Did COVID make us more susceptible to these ailments by impairing our immune function, since so many who got flu or RSV had just had COVID, which has known immune system impacts?  

Another question centered on what is known as “immune debt.” COVID lockdowns kept us from catching flu or RSV, so our immune responses were not as primed to respond to flu and RSV as they would have been if we’d been getting regularly exposed to those germs.  Did our resulting immune debt then lead to the unusual waves of these illnesses? Evidence suggests that answers to this question point towards both decreased overall immune function and germ-specific immune debt playing roles in this past winter’s flu and RSV surges.

Influenza typically spikes in the winter months in the U.S., and its timing and intensity vary a lot from year to year, so it is possible that last winter’s early flu surge was due purely to chance. Prior to the COVID lockdowns, however, RSV infected almost everyone by the time they were two years old, providing immunity to most children. During the COVID lockdowns, however, infants had little exposure to others and tended not to get infected with RSV. Last winter, therefore, the number of unexposed and non-immune infants in the U.S. was larger than usual. It is generally accepted that a portion of last winter’s RSV surge was due to those previously uninfected children catching RSV for the first time, as an unintended consequence of COVID lockdowns.


The number of cases involving a new type of difficult-to-treat fungal infection, Candida auris, has nearly doubled in 2021 compared to 2020 to just under 1,500 cases in the U.S. Persons with severe COVID requiring hospitalization had very high rates of Candida auris compared to others. It is not known if the COVID itself predisposed them to acquiring that fungus, whether medicines used to treat COVID were linked to Candida auris onset, or whether just being in the hospital and sick was the driver.

Common Bacterial Infections 

Clinicians are describing increases in common bacterial infectious diseases, including but not limited to Staph and sexually transmitted infections. Staph infections of the skin, blood and heart are increasing in number. Meanwhile, some sexually transmitted infections in the U.S., like syphilis and chlamydia, have reached levels not seen in decades. Additionally, the CDC has reported increases in brain abscesses in children during the last year.

Severe Strep Infections

This past year has also been characterized by documented increases in certain kinds of severe Strep infections. In the U.S., U.K., and in many European countries, there have been increases in “invasive” Strep infections for children under 10 years of age, that cause dangerous diseases like bloodstream infections, meningitis and flesh-eating bacteria syndromes. Right now the higher rates of invasive Strep infections are only associated with the COVID pandemic, and COVID has not been shown to be causal of the Strep surges. Nevertheless, the magnitude of the increases and number of countries reporting them is notable, leading to speculation about a link. Plus there is precedent for respiratory viral infections leading to increased Strep susceptibility, namely the 1918 flu pandemic noted above.

As researchers try to clarify the links between COVID and later infections like Strep, lab studies play a key role. From those studies, it is clear that some immune system cells (for example, CD8+ T cells) and the infection-fighting products they release are altered during and after COVID, in ways that can increase infection susceptibility. There are altered quantities of some immune system cells and their products after COVID, as well as differences in how well those cells function. A recent NIH press release noted that some of the COVID-related damage to our immune system cells leads to states of impaired immune protection, analogous to what is seen with HIV or hepatitis C disease.

In sum, while susceptibility to infection for any one person is influenced by many factors, we are seeing patterns emerge and lab studies result that suggest COVID increases subsequent  infection susceptibility, for some people, from some infections, for some amount of time. The magnitude of that influence likely varies widely from person to person. Further clarifying this matter is a priority, as we expect continued COVID presence for the foreseeable future..

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Dave Komendat retired as the Vice President and Chief Security Officer for The Boeing Company, a role he held for 14 years of his 36 years within the security profession. Komendat was responsible for the company’s global security and fire protection policy and procedures, site security, executive protection, supply chain and aviation security, structural and aircraft fire protection, government and proprietary information security, classified cyber security, strategic intelligence, international security, business continuity and disaster preparedness, Global Security Operations Center, and security background investigations.


Komendat was also the lead Boeing interface for both national and international security policy engagement with numerous government and industry advisory groups. He represented Boeing as past co-chairman and current board member on the Domestic Security Alliance Council, past President of The International Security Management Association and served as a member of the Threats and Information Committee for the Overseas Security Advisory Council.  


Komendat is the founder and President of DSKomendat Risk Management Services, he also serves on several company advisory boards and holds board leadership roles with several non-profit organizations whose missions are to protect people globally, including Hostage U.S. and The International Security Foundation. Dave is also a Strategic Engagement Advisor for the Office of Private Sector within the FBI. In 2018, Dave was awarded the Director’s Award for Exceptional Public Service by FBI Director Christopher Wray.


Komendat graduated from California State University at Long Beach and also attended and completed the executive development program at the Kellogg School of Management at Northwestern University.

Dr. Carter Mecher serves as the Medical Advisor for the Public Health Company. 


Prior to joining PHC, Carter served as a Senior Medical Advisor for the Office of Public Health in the U.S. Department of Veterans Affairs. In this position, Dr. Mecher played a key role in the COVID-19 outbreak response. 


From 2005 to 2011, he served as the Director of Medical Preparedness Policy at the White House Homeland Security Council and National Security Staff. He was a principal author of the National Strategy for Pandemic Influenza Implementation Plan. In this capacity, he helped set policy and devise strategies to mitigate the consequences of a pandemic and promote pandemic preparedness. 


Before serving at the White House, Dr. Mecher was the Chief Medical Officer for the Southeast VA Network in Atlanta from 1996 to 2005. In this role he oversaw the healthcare delivery for veterans in Alabama, Georgia and South Carolina. 


Dr. Mecher is a co-author of Lessons from the COVID War, an in-depth examination of the U.S. response to the pandemic. In addition, he is featured in Michael Lewis’ book The Premonition.


Dr. Mecher received his medical degree from Chicago Medical School and completed a residency in internal medicine and a fellowship in critical care medicine at Los Angeles County/USC Medical Center.

Dr. Joe DeRisi is a Scientific Advisor to PHC. He is one of the early pioneers of DNA microarray technology and whole genome expression profiling; he is nationally recognized in the field of genomic epidemiology for designing a first-of-its-kind initiative for COVID-19. Joe currently serves as Co-President of Chan Zuckerberg BioHub and is a professor of Biochemistry and Biophysics at University of California, San Francisco. He has a Bachelor of Arts in Biochemistry and Molecular Biology from University of California, Santa Cruz, and a Ph.D. in Biochemistry from Stanford University.

Dr. Sumiko Mekaru is the Vice President of Research and Innovation at The Public Health Company. Dr. Mekaru is an epidemiologist operating at the intersection of traditional epidemiology and technology and leading cross-disciplinary teams to solve challenges in public health. Prior to joining PHC, Dr. Mekaru was a Life Sciences Strategy, Policy, and Operations Expert at Booz Allen Hamilton where she recently led the development of COVID-19 forecasting models for disease transmission, resource utilization, and critical events for the Department of Defense. Dr. Mekaru has also led health technology teams at Epidemico and Boston Children’s Hospital, creating innovative health surveillance tools. She has published extensively on infectious disease outbreak monitoring, modeling, and surveillance. Dr. Mekaru holds a Doctor of Veterinary Medicine from Tufts University and a PhD in epidemiology from Boston University.

Justin McIntosh is an experienced professional with 10+ years in management and 8+ years in software engineering. Currently, he is the Vice President of Operations at The Public Health Company. His journey began in college when he co-founded Safe Site, a utility services company, which expanded to operations in three states with over 300 employees. After a successful exit, he founded Docusite, a construction risk management application, diving into software engineering. Despite challenges with Docusite, Justin’s passion for technology led him to various roles before landing at The Public Health Company.


In his current role, Justin is tackling the challenging task of improving operations in a remote environment. He is dedicated to his role and is always open to sharing experiences and insights. He is committed to nurturing effective teams, improving operations, and shaping innovative solutions. His focus is on creating a positive, growth-oriented environment and mentoring emerging leaders, reflecting his commitment to collective success.

Lori Sutton is the Vice President of Marketing at The Public Health Company. She is a strategic marketing visionary and global brand leader with 20+ years of progressive experience in B2B/B2C SaaS software marketing in large enterprise and SMB markets. She has expertise in leading strategy development, overhauling brands, launching products and driving growth in target verticals. Prior to joining PHC, Lori was the Vice President of Marketing and Growth at SMS-Magic, where she led the global GTM strategy, orchestrated a brand overhaul, developed new messaging and positioning and launched revenue generating campaigns. Lori held marketing and management roles at Model N, Bullet Point Network, Saba and other SaaS software companies where she focused on marketing strategy, business objectives and analytics to drive revenue.

Lori holds an MFA from California Institute of the Arts, a BFA from Virginia Commonwealth University, an Executive Education in Corporate Strategy at Harvard Business School and continues coursework at Massachusetts Institute of Technology.

Craig Katsuyama is the Vice President of Administrative Services at PHC. He brings extensive experience building companies from the ground up and was instrumental to the launch of IEX Group in 2012, which challenged the status quo of financial markets and created an entirely new stock exchange that works for all investors. Craig spent the last eight years at IEX where he built and oversaw the accounting and finance teams before transitioning to help establish IEX’s Event Stream business, a data messaging platform that applies IEX’s core technology to areas outside of finance. Craig graduated from Mount Allison University in New Brunswick, Canada with a Bachelor of Commerce in Accounting and Economics.

Dr. David Fisk is the Chief Medical Officer at The Public Health Company. Prior to joining PHC, Dr. Fisk served as an Infectious Disease Specialist at Sansum Clinic.  He serves as the Medical Director of Infection Prevention and Control at Cottage Health, leading the infection control team at Cottage, working with physicians and hospital leaders on the COVID Incident Command Center to ensure the highest level of preparation and care for patients. In early March 2020, before the first confirmed COVID-19 case in Santa Barbara County, Dr. Fisk advised that the virus was already spreading locally before community members were observing symptoms.


Dr. Fisk completed his medical degree from Johns Hopkins University School of Medicine and his Internal Medicine residency and Infectious Diseases fellowship at University of Michigan Medical Center. He is board certified in Infectious Diseases and a Fellow of the Infectious Diseases Society of America.

Chris Latko is the Chief Technology Officer at PHC. He joined as a Principal Software Architect where he played a key role in building out the platform. He has over 25 years experience in the technology sector holding positions at companies he started, Fortune 500 companies, and a multitude of startups both in the United States and Japan. He has spent the last decade designing, refining, and reimplementing architectures for hypergrowth startups such as Boxfish, Paxata (acquired by DataRobot), Banjo, and Globality. Chris earned two patents for designing a streaming data ingestion/data normalization platform.

Kendall Burman serves as PHC’s General Counsel and Chief Operating Officer. Prior to joining PHC, Burman held leadership roles at Alloy, a data and technology start-up for the progressive political market. Burman previously served as the Deputy General Counsel for Strategic Initiatives at the Department of Commerce and as Associate White House Counsel and Special Assistant to the President in the Obama Administration. She was also a counsel in the cybersecurity and data privacy practice at Mayer Brown and served as Chief Staff Counsel for President Obama’s 2008 campaign.


Burman is a graduate of Bowdoin College and received her J.D. from the University of Chicago where she was an editor of the law review. She was also was a fellow at both the New America Foundation and the Center for Democracy and Technology.

Dr. Charity Dean is the CEO, Founder and Chairman of The Public Health Company, a venture-backed Silicon Valley technology startup. 


In August 2020 Dr. Dean founded PHC, envisioning a commercial-grade global biosecurity platform to empower enterprises to manage biorisk at scale. Dr. Dean’s obsession with building a new solution was born out of 24 years in public health and the recognition that Silicon Valley innovations in artificial intelligence and machine learning could birth this entirely new capability. Two years later PHC PharosTM is a game-changer for numerous businesses providing real-time, dynamic risk management across their global footprint and assets. 


Dr. Dean founded PHC having served as the Assistant Director for the California Department of Public Health where she was part of the executive team under Governor Newsom running the COVID-19 pandemic response. She co-founded and co-chaired California’s COVID-19 Testing Task Force and under her leadership, California went from ranking last in the nation for testing to first in three months. In 2019, Dr. Dean served as Acting State Public Health Officer overseeing 4,300 staff with an annual operating budget of $3.5 billion. 


Before her move to statewide office, she served as the Public Health Officer for Santa Barbara County and oversaw a myriad of disease outbreaks and biological threats; she also served as attending physician for TB, HIV, and homeless medicine at the Santa Barbara Health Care Centers. 


Dr. Dean was awarded Physician of the Year in 2018 by the Central Coast Medical Association and honored as one of the Women of the Year by the California State Legislature.


Dr. Dean is a co-author of Lessons from the COVID War. Her work during the pandemic is the focus of Michael Lewis’ book The Premonition. Dr. Dean has shared her insights about the danger of biological threats and the changes we must make before the next crisis in a number of interviews and podcasts.


Dr. Dean holds a Doctor of Medicine and Master of Public Health and Tropical Medicine from Tulane University and a Bachelor of Science in Microbiology from Oregon State University.

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