American College of Physicians: Internal Medicine — Doctors for Adults ®

Monday, November 7, 2016

Flu, light, and the truth

I am getting a flu shot, and so are all members of my family, and you should, too. That's the simple truth in plain light, and unlike this dangerous infection, it involves no flux from year to year. That was my position last year at this time, and it will be my position next year.

Hence my title, a play on the words gracing the Yale University coat of arms I have walked by countless times over the past 25 years: Lux et Veritas (light and truth). This is just the right time for an annual booster of light and truth regarding the perennial menace of the flu, and our best defenses against it.

That we need such a booster at all is testimony to several things. First, the truth about flu recedes readily into the shadows of denial, conspiracy theories, and anti-scientific New Age nonsense. A bit of light is just the right disinfectant.

Second, the influenza virus is wily enough to require a reintroduction every year at this time. That's because the virus changes its protein coat annually, so last year's strain is yesterday's news. CDC epidemiologists do all they can to tell us what's coming each fall. Well, it's fall, and this year's verdict is in.

Let's start with a general primer. The “flu” refers to an upper respiratory infection caused by a small group of closely related viruses. The virulence, or strength of the flu strain, varies every year. The illness caused by the virus is never pleasant, but when the strain is very virulent, the illness can be severe. Although the flu, per se, generally does not cause death in otherwise healthy people, more than 30,000 premature deaths each year in the U.S. alone are attributed to influenza, mostly in older adults, the very young, or those prone to complications due to prior illness or a history of smoking.

When the flu strain is especially severe, being the right age or having generally good health make for less reliable defense. The single greatest infectious disease calamity in all of human history was not plague, or typhus, or smallpox, it was the 1918 flu pandemic, which killed as many as 50 million. Those who don't respect the flu just aren't paying attention.

Part of the toll of the 1918 pandemic was attributable to the strain of the flu, and part to the turmoil of World War I. But there was, of course, no vaccine in 1918 as there is now, and that may also partly explain why we have seen no commensurate outbreak since. Vaccination, however, is only protective when we roll up our sleeves, and too few of us do.

Most vaccines provide protection over an extended period of time. The flu vaccine is unique because the influenza germ itself is unique. It undergoes a process known as “antigenic drift” that changes the germ's surface proteins every year (that's the “flux”), so that this year's flu is generally uncovered by last year's vaccine. The CDC and the WHO track the emergence of flu strains in Asia each year, and develop a vaccine based on the particular surface proteins that predominate. The virus is also subject to more abrupt changes, known as “antigenic shift,” which occur when flu strains mingle with one another, usually in domestic animals, notably pigs and ducks. That is the process that produces pandemic strains of flu with reference to the source: avian, or swine.

Immunization works by priming our immune system to attack the virus by stimulating it with those surface proteins, known as antigens because they “generate” the formation of “antibodies.” The flu antigens in the vaccine look like the flu virus to our immune system. After the vaccine, if we are exposed to the flu, our immune system recognizes the germ as a foreign invader against which it has laid down preparations, and launches a quick and effective attack. When all goes as hoped, the virus is eradicated before we get sick.

In general, it takes our immune system several weeks after exposure to antigens to develop a robust supply of antibodies. Consequently, the best time for flu vaccine is before the bug is established among us. Based on continuous CDC surveillance, that's now.

We have recent evidence of what has been an obvious, advancing, and to those of us in public health, alarming trend over recent years: vaccine complacency, and vaccine opposition. The latest news on that front is survey research indicating that a high number of millennials don't plan to immunize their children. Perhaps this is the same group planning to sit out the presidential election, too, and count on nihilism at the sidelines to work out well. Good luck with that.

In case you are among the many dubious about flu vaccination specifically, and immunization in general, I will address it bluntly. By and large, doubts and conspiracy theories about vaccines are the privilege of the very societies that are the greatest beneficiaries of them. Stated differently, populations succumbing to polio and smallpox don't tend to fret the theoretical harms of vaccination. We needn't go so far; high rates of measles, mumps, and rubella tend to make vaccine enthusiasts of parents as well.

The flu vaccine does not cause the flu—ever. It can't because the vaccine does not contain a virus, just proteins. There is no infectious agent in the vaccine; viral proteins cannot replicate or cause disease (N.B. the nasal flu vaccine does contain live virus, but is not recommended this year). Everyone knows someone who swears they got the flu after the flu shot. The problem is, we often refer to any severe upper respiratory illness as “the flu” (while referring to less severe cases as “a cold”), and viral upper respiratory infections are common in the fall and winter when the flu shot is given. If you get a viral infection shortly after getting the flu shot, you may assume it is due to the vaccine, even though it is not. The immune system response to the vaccine can at times make people feel slightly ill for several days, but that's a far cry from a true bout of flu, which tends to last more than a week and cause, among other things, severe muscle pain and high fever.

Doubts also seem to abound about the effectiveness of the flu vaccine. It is certainly far from perfect, and the elderly, who most need protection, may need two inoculations to get it. But leaving aside some of the subtleties that complicate measuring vaccine effectiveness in real-world settings, and applying even a low level estimate of overall vaccine effectiveness, routine flu vaccination produces a decisive overall benefit compared to just taking our chances with the flu. There have been also been recent improvements to the vaccine to enhance immune responses in those who most need such help.

But there's another key consideration here, courtesy not of epidemiologists, but the poet and preacher, John Donne: no one is an island. Your vaccine may save someone else's life. While true that the elderly most need protection and benefit least from vaccination, there is another way to protect our older loved ones: vaccinate ourselves and our children. People who can't get the flu can't transmit the flu to those most vulnerable to it and its complications. This is called “herd immunity,” and it is an important reason why smallpox and polio no longer threaten us all.

Whatever your doubts about the influenza vaccine, it is an established fact that immunization is many times―many times―safer than the flu itself. That does not mean flu is a plague each year, nor that the vaccine is perfectly safe. Nothing in medicine and little in life is perfectly safe. Harm from the flu vaccine is possible, but a highly remote risk. As noted, I readily accept that risk every year not only for myself, but for my beloved wife and children as well (or at least I did all the years they lived at home). I put the arms of the people I love most on the planet where my mouth is on this topic.

There are several reasons why the potential harms of flu vaccine may loom much larger in the imagination than they actually are. First, any adverse event, an allergic reaction, the now exceedingly rare case of Guillain-Barré syndrome, is amplified many orders of magnitude by repetition in the blogosphere. One case, appearing on 50,000 websites, exerts the influence of 50,000 cases. The same is true even when the allegations are entirely false, like the non-existent link between immunization and autism.

But at least as important, we are generally blasé about risks that lack the intrigue of conspiracy. So, for instance, consider if flu infects one person in five, and kills one person per 10,000 infected. There is certainly a good chance you, if healthy, would not be among those who get the flu. There is a very good chance the majority of people you know would not get the flu, either. And you are very unlikely to know anyone who is killed by flu.

But one infection per five means 60 million or so infections nationally. One death per 10,000 of these infections might be invisible in your circle of friends and family, but it would mean 6,000 deaths nationwide. This is consistent with a quite mild flu season in the U.S.

In contrast, the most dangerous flu vaccine in history, the notorious swine flu debacle of 1976, when there were adulterated vaccines in the mix, was associated with 25 deaths. That's bad, but it is more than two orders of magnitude less bad than even the mildest of flu seasons.

Another argument I hear against vaccination is like that proverbial “Uncle Joe” everyone knows, who smoked 3 packs a day and lived to be 119. It could happen, but I wouldn't bet the farm on it. Uncle Joe is that rare character who somehow comes away from a train crash with a minor flesh wound. The rest of us are mortal.

There is something more fundamentally wrong with the “I've never gotten the flu, and therefore don't need to be vaccinated” stance than the Uncle Joe fallacy. Let's face it, those who were ultimately beneficiaries of small pox or polio immunization never had small pox or polio, either. If they ever had, it would have been too late for those vaccines to do them any good.

The trouble with serious illness is that one time can be one time too many.

Familiarity breeds contempt, or at least complacency, and perhaps the annual return of influenza has induced that response. Perhaps that's why we seem to be dismissive of this germ, and overlook what a serious illness it can be. But that tendency is at our peril.

I do understand the reasons for reticence about immunization in general, and flu immunization in particular. For any vaccine to do us any good, we need to get it while feeling fine. This is quite different from, say, an operation that is much more dangerous, but easily justified by the obviously hemorrhaging bullet hole, plugged up gall bladder or occluded arteries. Convinced as I am of the benefits of immunization, I feel a momentary hesitation each year myself. But I get over it, and roll up my sleeve. I recommend you do the same.

If I've failed to convince you, or you get the vaccine too late to prevent influenza, there is medication available to shorten the course of illness and reduce the risk of complications. If you develop fever, headache, cough and/or body aches, contact your doctor to find out if you are a candidate. The CDC provides very helpful information about antiviral medications on-line.

The simple truth is that the flu ranks among the great infectious disease killers in human history, and is an unusually wily germ into the bargain. Even a garden-variety bout is apt to lay you out for a week or more. There is flux in the composition of the virus year to year, but none in the public health recommendation based on science, sense, and the dispassionate light of epidemiology. You should defend yourself and your loved ones from this perennial threat.

David L. Katz, MD, FACP, MPH, FACPM, is an internationally renowned authority on nutrition, weight management, and the prevention of chronic disease, and an internationally recognized leader in integrative medicine and patient-centered care. He is a board certified specialist in both Internal Medicine, and Preventive Medicine/Public Health, and Associate Professor (adjunct) in Public Health Practice at the Yale University School of Medicine. He is the Director and founder (1998) of Yale University's Prevention Research Center; Director and founder of the Integrative Medicine Center at Griffin Hospital (2000) in Derby, Conn.; founder and president of the non-profit Turn the Tide Foundation; and formerly the Director of Medical Studies in Public Health at the Yale School of Medicine for eight years. This post originally appeared on his blog at The Huffington Post.

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Members of the American College of Physicians contribute posts from their own sites to ACP Internistand ACP Hospitalist. Contributors include:

Albert Fuchs, MD
Albert Fuchs, MD, FACP, graduated from the University of California, Los Angeles School of Medicine, where he also did his internal medicine training. Certified by the American Board of Internal Medicine, Dr. Fuchs spent three years as a full-time faculty member at UCLA School of Medicine before opening his private practice in Beverly Hills in 2000.

And Thus, It Begins
Amanda Xi, ACP Medical Student Member, is a first-year medical student at the OUWB School of Medicine, charter class of 2015, in Rochester, Mich., from which she which chronicles her journey through medical training from day 1 of medical school.

Ira S. Nash, MD, FACP, is the senior vice president and executive director of the North Shore-LIJ Medical Group, and a professor of Cardiology and Population Health at Hofstra North Shore-LIJ School of Medicine. He is Board Certified in Internal Medicine and Cardiovascular Diseases and was in the private practice of cardiology before joining the full-time faculty of Massachusetts General Hospital.

Zackary Berger
Zackary Berger, MD, ACP Member, is a primary care doctor and general internist in the Division of General Internal Medicine at Johns Hopkins. His research interests include doctor-patient communication, bioethics, and systematic reviews.

Controversies in Hospital Infection Prevention
Run by three ACP Fellows, this blog ponders vexing issues in infection prevention and control, inside and outside the hospital. Daniel J Diekema, MD, FACP, practices infectious diseases, clinical microbiology, and hospital epidemiology in Iowa City, Iowa, splitting time between seeing patients with infectious diseases, diagnosing infections in the microbiology laboratory, and trying to prevent infections in the hospital. Michael B. Edmond, MD, FACP, is a hospital epidemiologist in Iowa City, IA, with a focus on understanding why infections occur in the hospital and ways to prevent these infections, and sees patients in the inpatient and outpatient settings. Eli N. Perencevich, MD, ACP Member, is an infectious disease physician and epidemiologist in Iowa City, Iowa, who studies methods to halt the spread of resistant bacteria in our hospitals (including novel ways to get everyone to wash their hands).

db's Medical Rants
Robert M. Centor, MD, FACP, contributes short essays contemplating medicine and the health care system.

Suneel Dhand, MD, ACP Member
Suneel Dhand, MD, ACP Member, is a practicing physician in Massachusetts. He has published numerous articles in clinical medicine, covering a wide range of specialty areas including; pulmonology, cardiology, endocrinology, hematology, and infectious disease. He has also authored chapters in the prestigious "5-Minute Clinical Consult" medical textbook. His other clinical interests include quality improvement, hospital safety, hospital utilization, and the use of technology in health care.

Juliet K. Mavromatis, MD, FACP, provides a conversation about health topics for patients and health professionals.

Dr. Mintz' Blog
Matthew Mintz, MD, FACP, has practiced internal medicine for more than a decade and is an Associate Professor of Medicine at an academic medical center on the East Coast. His time is split between teaching medical students and residents, and caring for patients.

Everything Health
Toni Brayer, MD, FACP, blogs about the rapid changes in science, medicine, health and healing in the 21st century.

Vineet Arora, MD, FACP, is Associate Program Director for the Internal Medicine Residency and Assistant Dean of Scholarship & Discovery at the Pritzker School of Medicine for the University of Chicago. Her education and research focus is on resident duty hours, patient handoffs, medical professionalism, and quality of hospital care. She is also an academic hospitalist.

Glass Hospital
John H. Schumann, MD, FACP, provides transparency on the workings of medical practice and the complexities of hospital care, illuminates the emotional and cognitive aspects of caregiving and decision-making from the perspective of an active primary care physician, and offers behind-the-scenes portraits of hospital sanctums and the people who inhabit them.

Gut Check
Ryan Madanick, MD, ACP Member, is a gastroenterologist at the University of North Carolina School of Medicine, and the Program Director for the GI & Hepatology Fellowship Program. He specializes in diseases of the esophagus, with a strong interest in the diagnosis and treatment of patients who have difficult-to-manage esophageal problems such as refractory GERD, heartburn, and chest pain.

I'm dok
Mike Aref, MD, PhD, FACP, is an academic hospitalist with an interest in basic and clinical science and education, with interests in noninvasive monitoring and diagnostic testing using novel bedside imaging modalities, diagnostic reasoning, medical informatics, new medical education modalities, pre-code/code management, palliative care, patient-physician communication, quality improvement, and quantitative biomedical imaging.

Informatics Professor
William Hersh, MD, FACP, Professor and Chair, Department of Medical Informatics & Clinical Epidemiology, Oregon Health & Science University, posts his thoughts on various topics related to biomedical and health informatics.

David Katz, MD
David L. Katz, MD, MPH, FACP, is an internationally renowned authority on nutrition, weight management, and the prevention of chronic disease, and an internationally recognized leader in integrative medicine and patient-centered care.

Just Oncology
Richard Just, MD, ACP Member, has 36 years in clinical practice of hematology and medical oncology. His blog is a joint publication with Gregg Masters, MPH.

Kevin Pho, MD, ACP Member, offers one of the Web's definitive sites for influential health commentary.

MD Whistleblower
Michael Kirsch, MD, FACP, addresses the joys and challenges of medical practice, including controversies in the doctor-patient relationship, medical ethics and measuring medical quality. When he's not writing, he's performing colonoscopies.

Medical Lessons
Elaine Schattner, MD, FACP, shares her ideas on education, ethics in medicine, health care news and culture. Her views on medicine are informed by her past experiences in caring for patients, as a researcher in cancer immunology, and as a patient who's had breast cancer.

Mired in MedEd
Alexander M. Djuricich, MD, FACP, is the Associate Dean for Continuing Medical Education (CME), and a Program Director in Medicine-Pediatrics at the Indiana University School of Medicine in Indianapolis, where he blogs about medical education.

More Musings
Rob Lamberts, MD, ACP Member, a med-peds and general practice internist, returns with "volume 2" of his personal musings about medicine, life, armadillos and Sasquatch at More Musings (of a Distractible Kind).

David M. Sack, MD, FACP, practices general gastroenterology at a small community hospital in Connecticut. His blog is a series of musings on medicine, medical care, the health care system and medical ethics, in no particular order.

Reflections of a Grady Doctor
Kimberly Manning, MD, FACP, reflects on the personal side of being a doctor in a community hospital in Atlanta.

The Blog of Paul Sufka
Paul Sufka, MD, ACP Member, is a board certified rheumatologist in St. Paul, Minn. He was a chief resident in internal medicine with the University of Minnesota and then completed his fellowship training in rheumatology in June 2011 at the University of Minnesota Department of Rheumatology. His interests include the use of technology in medicine.

Technology in (Medical) Education
Neil Mehta, MBBS, MS, FACP, is interested in use of technology in education, social media and networking, practice management and evidence-based medicine tools, personal information and knowledge management.

Peter A. Lipson, MD
Peter A. Lipson, MD, ACP Member, is a practicing internist and teaching physician in Southeast Michigan. The blog, which has been around in various forms since 2007, offers musings on the intersection of science, medicine, and culture.

Why is American Health Care So Expensive?
Janice Boughton, MD, FACP, practiced internal medicine for 20 years before adopting a career in hospital and primary care medicine as a locum tenens physician. She lives in Idaho when not traveling.

World's Best Site
Daniel Ginsberg, MD, FACP, is an internal medicine physician who has avidly applied computers to medicine since 1986, when he first wrote medically oriented computer programs. He is in practice in Tacoma, Washington.

Other blogs of note:

American Journal of Medicine
Also known as the Green Journal, the American Journal of Medicine publishes original clinical articles of interest to physicians in internal medicine and its subspecialities, both in academia and community-based practice.

Clinical Correlations
A collaborative medical blog started by Neil Shapiro, MD, ACP Member, associate program director at New York University Medical Center's internal medicine residency program. Faculty, residents and students contribute case studies, mystery quizzes, news, commentary and more.

Interact MD
Michael Benjamin, MD, ACP member, doesn't accept industry money so he can create an independent, clinician-reviewed space on the Internet for physicians to report and comment on the medical news of the day.

PLoS Blog
The Public Library of Science's open access materials include a blog.

White Coat Rants
One of the most popular anonymous blogs written by an emergency room physician.

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