Blog

History of Vaccines Blog


June 14, 2010

The Historical Medical Library here at The College of Physicians of Philadelphia holds seven floors of stacks of books, journals, and archives. The scale of the library, and its testament to human illness, can be overwhelming. Our recent research on tuberculosis provides an example: standing in the stacks, surrounded by row upon row of books about TB, is a grim experience. But though our library gives the impression that TB is an historical artifact, it’s most certainly not. It continues to take an enormous global toll: there are 9.4 million new infections a year, and there were 1.3 million deaths from TB in 2008 alone. One of these recent trips into the stacks led us to the Final Report of the International Tuberculosis Campaign (1951), an optimistic portrait of the promises of an early immunization campaign. The book offers comprehensive statistics of the massive tuberculosis campaign undertaken in 23 countries in the late 1940s and early 1950s. The project initially began as a Scandinavian Red Cross effort in Europe in the aftermath of World War II. Tuberculosis rates had soared in the disruption and privation the war created. In Poland, tuberculosis rates among children had quadrupled. As Niels Brimnes writes, the president of the Danish Red Cross announced on the radio in 1948, “The spirit of the Nordic Vikings has been part of this campaign as in the old days. Earlier we went out sword in hand to conquer and fight each other. Today we go out together with the needles as our only weapon to fight the scourge of the Second World War: tuberculosis” (Niels Brimnes, “Vikings against Tuberculosis: The International Tuberculosis Campaign in India”). Read More...

Posted in: Historical Medical Library, Tuberculosis

June 10, 2010

One of the main challenges presented by influenza is the virus’s tendency to undergo genetic change. Seasonal influenza virus strains change frequently and, as a result, new vaccines are needed each year to provide protection against the new strains. That’s problematic for two reasons, however: first, it takes time to develop new vaccines, even though the techniques and procedures for doing so are well-established; and second, even after a vaccine is developed and mass-produced, it still has to be distributed and administered to millions of people. Both of these steps require a lot of time, an efficient infrastructure, and a large, coordinated effort to achieve. In response, researchers are trying to develop an influenza vaccine that can provide broad protection against influenza–including future strains–so that a single vaccination would be enough to protect an individual from the seasonal flu for three, five, perhaps even ten years or more. Past influenza vaccines have targeted a particular segment of the hemagglutinin (HA) protein that allows influenza viruses to attach to and enter cells. (There are many different hemagglutinin subtypes; avian flu, for example–H5N1–is of hemagglutinin subtype 5, while the novel H1N1 “swine flu” is of type 1.) To this point, flu vaccines have focused on the “globular head” of the HA protein, the part of its structure most frequently targeted by antibodies to influenza. Unfortunately the globular head, like influenza viruses as a whole, is subject to frequent genetic changes–so researchers are focusing on a different part of the HA protein’s structure. Read More...

Posted in: General, Influenza, Vaccine Research

June 7, 2010

Ebolavirus, also known simply as Ebola, gained notoriety in the United States in 1989 and 1990, when imported monkeys infected with a subtype of the virus were introduced to quarantine facilities in Virginia, Pennsylvania, and Texas. The viral species isolated from the infected monkeys at a Reston, Virginia lab was eventually named Ebola-Reston, and the incident was documented in Richard Preston’s best-selling 1994 book The Hot Zone. Yet while Ebola-Reston proved quite dangerous to monkeys, it did not cause illness in humans: though some humans exposed to it developed antibodies, none experienced any symptoms. Other species of Ebola, however, are far more dangerous. Ebola-Reston is only one of five known species of Ebola, and is the only one of the five that has never caused serious human illness. Of the others–Ebola-Zaire, Ebola-Sudan, Ebola-Ivory Coast, and Ebola-Bundibugyo–all but Ebola-Ivory Coast have led to varying rates of fatalities since the first known outbreak of Ebola-Zaire killed 88% of infected patients in 1976. Read More...

Posted in: General, Vaccine Research

June 1, 2010

*Update* -- Note that the Advisory Committee on Immunization Practices voted on October 27, 2010, for new recommendations regarding Tdap vaccination. For more information, see our blog post "Advisory Committee Votes for Expanded Pertussis Vaccine Recommendations." -- HOV Staff Guest Post byAndreas Bollmann, MD, PhD, FAAP Pediatric Associates Inc. Since December 2006, the Advisory Committee on Immunization Practices (ACIP) has recommended the use of Tdap (tetanus and diphtheria toxoids, acellular pertussis vaccine) instead of Td (tetanus and diphtheria toxoid immunization) during adolescence and at least once during adulthood. Most adults don’t worry about whooping cough (also known as pertussis). Once a patient has moved on from a pediatrician’s care, this disease usually falls off everybody’s radar. In fact, vaccination rates among adults in the United States against pertussis are estimated to be very low. Studies show that about 75% of pertussis infections among babies are contracted from household members. Pertussis cases reported from 2000 to 2003 have risen (and it is likely they are even higher, since only a small percentage of cases are actually reported). From 2000-2004, 92 deaths occurred in infants (12 month of age and younger) in the United States. From 2004-2005, 66 deaths occurred. And just recently, California health officials reported that pertussis cases so far in 2010 have more than doubled from the same period in 2009. Already this year in California, four infants have died from the disease. Read More...

Posted in: General, Pertussis (whooping cough)

May 20, 2010

On Monday, May 17, staff from the History of Vaccines project traveled to Washington, D.C. to attend “New Promise in the Search for HIV, TB and Malaria Vaccines,” a joint briefing held on the 30th anniversary of the eradication of smallpox. In their opening remarks, Dr. Alan Bernstein (Global HIV Vaccine Enterprise), Dr. R. Gordon Douglas, Jr. (Aeras Global TB Vaccine Foundation) and Colonel Chris Ockenhouse (U.S. Military Malaria Vaccine Program, Walter Reed Army Institute of Research) all stressed the need for continued efforts toward vaccines for malaria, HIV, and TB. They also highlighted the overlap between the incidence of the three diseases, as well as the interaction between them: Douglas specifically stressed the importance of developing a TB vaccine that can be used in HIV-positive individuals. We at the History of Vaccines project were happy to provide material for the keynote talk by Dr. Gregory Poland (Vaccine Research Group, Mayo Clinic). Dr. Poland discussed historical and contemporary challenges in vaccine development and deployment, including political agendas and the threat of diseases as bioweapons post-eradication. Read More...

Posted in: Vaccine Research, Tuberculosis, HIV, General

May 17, 2010

At the University of Pennsylvania School of Medicine on May 14, Arthur L. Caplan, PhD, Emmanuel and Robert Hart Director of the Center for Bioethics and the Sydney D. Caplan Professor of Bioethics at the University of Pennsylvania, gave a talk entitled “Ethical Lessons of Swine Vaccine Rationing.” Caplan, a widely quoted voice in bioethics, noted that the 2009 H1N1 pandemic provided testing ground for pandemic and even bioterror response planning. What can we learn from the experience? Caplan described several areas for improvement. First, he noted the plethora of plans, developed at different levels of authority, for dealing with the pandemic. Hospitals, corporations, cities, and states developed plans with different priorities and rationales, some of them potentially at odds. Caplan highlighted the conflict between, for example, a state that might decide to quarantine itself to attempt to reduce importation of disease and a vaccine manufacturer in that state with a need to distribute its product. Would the state plan necessarily take the manufacturer’s needs into account? Read More...

Posted in: Influenza, Ethics

May 13, 2010

Most people view chickenpox as a disease of childhood–or, as the vaccine against it is increasingly used, as a disease of the past. But varicella zoster, the herpes virus that causes chickenpox, is sneaky. Even after a varicella infection clears, the virus hides in the nerve cells, inactive. In about 20% of people who have had chickenpox, the virus will reappear later in life to cause shingles, a disease of severe pain and blisters on the body or face. Blisters on the face can cause problems with vision and hearing, while the spread of the disease to the body’s internal organs can cause serious damage, including encephalitis (inflammation in the brain). A vaccine against shingles was approved by the U.S. Food and Drug Administration in 2006 after it was shown to be effective (in clinical trials, the vaccine reduced the risk of shingles by 50%). Recently, a long-term follow-up study of 38,000 participants from the trial that led to its approval also demonstrated its long-term safety. (The study, from the Annals of Internal Medicine, can be found here.) The use of the vaccine, however, does not reflect the data on its safety or effectiveness: a separate study, also in the Annals of Internal Medicine, indicated that despite the vaccine being available since 2006 and recommended since 2008 by the Advisory Committee on Immunization Practices for all adults 60 or older, early use of the vaccine has been between only 2% and 7% in the United States. (That study can be found here.) Read More...

Posted in: Varicella zoster, General

May 10, 2010

The United States Food and Drug Administration (FDA) recently approved Dendreon Corporation’s “cancer vaccine,” Provenge, for the treatment of certain types of prostate cancer. It became the first cancer vaccine to be approved for use in the United States. (Gardasil, Merck’s HPV vaccine, is sometimes referred to as an anti-cancer vaccine since it prevents infection with strains of HPV that cause cervical cancer. Dendreon’s product, however, is designed to directly treat cancer.) Provenge is not a vaccine in the same way we would think about vaccines against measles, polio, or other infectious diseases. Those vaccines are designed to prevent infection by priming the immune system against a particular pathogen: a strain of a virus is weakened or inactivated, for example, and a mass-produced vaccine is created that can be administered for future protection against that virus before it can take hold in the body. Provenge, however, is designed to treat existing cases of advanced prostate cancer, not prevent cancer. It works in a similar way to what we think of as a typical vaccine: by priming a person’s immune system to attack the disease. Attacking cancer is complicated, however, since cancer cells are actually the body’s own cells, making it difficult to “teach” a person’s immune system to identify them. Provenge is designed to stimulate a T-cell response to prostate cancer cells that are present. Read More...

Posted in: General, Vaccine Research

May 8, 2010

In the not-so-distant past, smallpox was a scourge of mankind. It spread wildly through vulnerable populations, killing up to 30% of those it infected; those who survived were left scarred, some seriously disfigured or blind. Smallpox ravaged the world’s population essentially unchecked for more than 3,000 years, sickening Egyptian pharaohs, British royalty, American presidents, and millions in between. But in the 1970s, the disease was nearing the end of its reign. Thanks to massive vaccination and surveillance efforts, smallpox became the first disease to be eradicated from the world. Today, we celebrate 30 years since the people of the world declared themselves free of its grasp. The last stand The final case of naturally occurring smallpox took place in Somalia in October of 1977, in a cook named Ali Maow Maalin. Personnel from the global eradication program immediately began efforts to find every individual Maalin had been in contact with, doing house-by-house searches and vaccinating anyone entering or leaving his town. By December 29, 1977, they completed a national search, and Maalin’s case proved to be the last. He survived. Read More...

Posted in: General, Interviews, Smallpox

May 6, 2010

In the United States, the Advisory Committee on Immunization Practices (ACIP) issues written recommendations regarding scheduling and dosing of vaccinations for both children and adults. ACIP members are selected by the Secretary of the Department of Health and Human Services to provide advice on controlling vaccine-preventable diseases; the committee is the only federal unit to make these recommendations. ACIP issues new and updated recommendations when the status of a given disease changes, or when new data suggests that a vaccine dosage or schedule should be changed. Recently, in response to rabies surveillance data, clinical studies, experimental work and other factors, the Committee issued new recommendations for prophylactic rabies vaccination after possible exposure to the virus. Rabies is nearly always fatal after symptoms begin to appear. However, if an exposed individual is treated promptly (with proper wound care and the administration of rabies immune globulin and rabies vaccine), the disease can usually be prevented. The previous ACIP recommendations were for five doses of rabies vaccine following exposure; now, the ACIP has reduced the dosage schedule, recommending only four doses of the vaccine for exposed individuals without prior protection against the disease. The details of ACIP’s updated recommendations are available as part of the March 19, 2010 Morbidity and Mortality Weekly Report. Read More...

Posted in: Rabies, General