History of Vaccines Blog
I've been closely following, as I'm sure most of you have, the recent outbreaks of measles originating from exposures at Disneyland. I wrote about this the other day (and included some information about a lesser-known measles outbreak in a small South Dakota town). Since then, reported cases of measles have climbed. As of the writing of this post, 88 measles cases have been reported and linked directly or indirectly to the initial exposures at Disneyland. It's too soon to know the vaccination history of every person who has developed measles, but usually what we see in measles outbreaks is that the great majority of cases are completely unvaccinated. A smaller number will have had one vaccine (not the recommended two), and an even smaller number will have been fully vaccinated. This is no surprise: the measles vaccine is highly effective at preventing disease, but 2-5% of individuals vaccinated once do not respond to the vaccine. So, some vaccinated individuals will remain unprotected.
January 14, 2015
The CDC just announced its final 2014 measles case numbers. They have reported 644 cases for 2014, the highest number of measles cases in any year since measles was declared eliminated in 2000. The graph below shows measles cases since 2001 up to November 29, 2014. December ended with a bang: between December 15 and December 20, visitors to Disneyland in Anaheim, California, were exposed to measles courtesy of an as-yet-unidentified index case. Related measles cases have been reported in California (22 so far), Utah (2), Washington (1) and Colorado (1). From November 29 to December 31, a total of 31 measles cases were reported across the country.
We've all been following the National Hockey League mumps outbreak in the past few weeks. And by now, those of us who are known for opining on infectious diseases have been asked by our friends why even people who are fully and recently vaccinated are coming down with the disease. (Here's the short version: Two doses of mumps vaccine are 88% (range: 66-95%) effective at preventing disease, so in an outbreak, a certain percentage of fully (2 doses) and partially (1 dose) immunized individuals are vulnerable to becoming ill, as are all the unvaccinated people exposed. For more information see Mumps Vaccine Effectiveness in Highly Immunized Populations and Mumps Outbreaks in Vaccinated Populations: Are Available Mumps Vaccines Effective Enough to Prevent Outbreaks?)
December 11, 2014
For National Influenza Vaccination Week, I had the pleasure of interviewing Dalton G. Paxman, PhD, FCPP, Regional Health Administrator for the mid-Atlantic region, where he oversees public health initiatives for the Office of the Assistant Secretary for Health (OASH), U.S. Department of Health and Human Services (HHS). Dr. Paxman is a Fellow here at The College of Physicians of Philadelphia. Influenza season has begun – has there been much influenza nationally yet? What kind of activity are we seeing in HHS Region 3? Flu activity is beginning to increase in parts of the United States and CDC is getting reports of flu illnesses, flu hospitalizations, and flu deaths. Influenza A (H3N2) viruses are most common so far. H3N2 predominant seasons are associated with more severe illness and mortality, especially in older people and young children, than during H1N1- or B-predominant seasons. If H3N2 viruses continue to predominate, this season could be severe.
December 10, 2014
It's National Influenza Immunization Week, an observance sponsored every year by the CDC to highlight the national immunization influenza vaccination recommendations. For the past several years, all US individuals in the United States over 6 months of age have been recommended by the Advisory Committee on Immunization Practices to get the influenza vaccine. This influenza season has already been eventful, not only in terms of morbidity and mortality, with five pediatric deaths reported, but also in terms of questions about influenza vaccination effectiveness. First, earlier this fall CDC announced a puzzling finding: in certain groups of children during the 2013-14 flu season, the live attenuated influenza vaccine was less effective against the circulating H1N1 virus than the inactivated vaccine. This finding was unexpected because the live vaccine has in other seasons provided superior protection than the inactivated vaccine.
December 2, 2014
You’ve read the headlines, now you can learn the facts. Ebola: Let's Talk About This Virus is an opportunity for medical and non-medical audiences to learn more about Ebola virus and Ebola virus disease from specialists. Speakers will address questions such as, What are viral hemorrhagic fevers and why are they unique? How can Ebola virus disease be prevented, controlled, and treated? What is the impact of geographic location on disease transmission? What does the future hold in terms of treatment options?
October 27, 2014
Here at The College of Physicians of Philadelphia we have about 44 full- and part-time staff people. When a cold or the flu is going around, 10% to 20% of staff can be at home sick. That makes staffing a challenge, particularly because we have to have enough personnel here to sell tickets to the Mütter Museum and staff the museum store. In winter 2013, I polled the employees here and found that only 43% had gotten the flu vaccine in the 2012-13 season. To try to boost our uptake of the vaccine, in fall 2013 I organized a flu vaccine awareness campaign. The result was that about 70% of staffers got the vaccine for the 2013-14 season. This year we decided to reduce all the barriers to vaccination (the trip to the doctor or the pharmacy, needing one's insurance card, inertia), and we brought a pharmacist here to give the trivalent inactivated influenza vaccine to any staffers or contractors who wanted it. As an incentive, and like last year, we gave a $10 Trader Joe's gift card to anyone who got the vaccine.
October 20, 2014
A few weeks ago, I attended a talk by the CDC's Anne Schuchat, MD, on US HPV vaccination that she subtitled “How Not to Introduce a Vaccine.” In spite of the promise of HPV vaccines to reduce the burden of cervical and other cancers in this country, uptake of the complete three-dose series has lagged far behind the other vaccines on the adolescent immunization platform. On Friday, I heard a more optimistic talk about HPV vaccination in African countries by Helen Rees, MD, MA, Executive Director, Wits Reproductive Health and HIV Initiative, University of Witswatersrand. Dr. Rees is a member of the WHO immunization policy committee and has a background in pediatrics, HIV care, and obstetrics and gynecology. She spoke as a guest of the Johns Hopkins Vaccine Initiative as part of their annual Vaccine Day events. Globally, 90% of HPV-related cancers are cervical cancers, and sub-Saharan Africa is, as Rees said, the epicenter for cervical cancer. The high prevalence of HIV infection, which is a risk factor for oncogenic HPV infection, and the lack of access to HPV screening contribute to the high HPV disease burden. And apart from HPV-related cancers, Rees also noted that genital warts are not a trivial condition in an HIV-prevalent setting: they can be debilitating in those with compromised immune systems. The quadrivalent HPV vaccine offers protection from the two most common types of oncogenic HPVs and two types that cause genital warts; the bivalent vaccine covers only the two most common types of oncogenic HPVs.
How is the immune system similar to your marathon time? As we age, our immune response decreases at the same slope that our marathon race times increase. Presenters laid out this and some of the other problems of immunizing adults in the Symposium on Adult Immunizations, an early session at the Infectious Diseases Society 2014 conference at the Philadelphia Convention Center. Kenneth Schmader, MD, noted that though adults age differently – some adults at age 75 may be running marathons while others may be frail – all are subject to immune system senescence, and all are vulnerable to rapid functional declines that may result from an acute stressor, whether it’s a fall or a debilitating case pneumococcal pneumonia.
September 24, 2014
On Monday, September 22, in Philadelphia, Matthias J. Schnell, PhD, of the Jefferson Vaccine Center, announced that one of his lab's Ebola virus vaccine candidates was moving into human trials. Funding from the National Institute of Allergy and Infectious Diseases and the Department of Defense will allow production of a clinical lot of the vaccine for a Phase 1 trial that could be completed as early as mid-2015 (see Anthony Fauci's testimony to the House Foreign Affairs Committee). Schnell addressed a gathering of diplomats, scientists, and large audience of students and healthcare professionals at Thomas Jefferson University to discuss the Ebola epidemic in West Africa. Ambassadors of Sierra Leone, Ivory Coast, and Guinea spoke about the difficulties of epidemic response in their countries, which are especially complex given the legacies of years of civil unrest there.