Archive for November, 2011

Decision making in immunization

Tuesday, November 8th, 2011 (last updated)

The world is changing fast, but so is our understanding of how we understand that world. We make decisions everyday, but are we really as rational as we believe? And how is social media changing our expectations for communication and social interaction? This thought provoking video leads us to question how well we really understand our own decisions, particularly around immunization – a central pillar of any public health system. We need to better understand immunization decision making if we are to re-balance public perceptions of vaccination.

Sanofi Pasteur

Scientists Outline Steps Toward Epstein-Barr Virus Vaccine

Monday, November 7th, 2011 (last updated)

Epstein-Barr virus (EBV) infects nine out of ten people worldwide at some point during their lifetimes. Infections in early childhood often cause no disease symptoms, but people infected during adolescence or young adulthood may develop infectious mononucleosis, a disease characterized by swollen lymph nodes, fever and severe fatigue. EBV also is associated with several kinds of cancer, including Hodgkin lymphoma and stomach and nasal cancers.

Organ transplant recipients and people infected with HIV (who become infected with or who already are infected with EBV) also may develop EBV-associated cancers. There is no vaccine to prevent EBV infection and no way for doctors to predict whether an EBV-infected person will develop virus-associated cancer.

In a new article from the National Institutes of Health (NIH), Anthony S. Fauci, M.D., director of the National Institute of Allergy and Infectious Diseases (NIAID), and Harold Varmus, M.D., director of the National Cancer Institute (NCI), join Gary Nabel, M.D., Ph.D., director of NIAID’s Vaccine Research Center, and Jeffrey Cohen, M.D., chief of NIAID’s Laboratory of Infectious Diseases, in summarizing a recent meeting of experts who gathered to map directions toward an EBV vaccine. Although it may not be possible to create a vaccine that completely prevents EBV infection, the authors note, clinical observations and results from clinical trials of an experimental EBV vaccine suggest that it may be possible to create an EBV vaccine capable of preventing the diseases that sometimes follow EBV infection.

Priorities for future research include determining which immune system responses to vaccination correlate with protection from infection or disease; identifying biological markers that would enable clinicians to predict development of EBV-related cancers; and establishing collaborations among government, academic and industry scientists to further improve an experimental EBV vaccine and to spur development of second-generation EBV vaccines.

Science Daily

Immunizations and vaccines

Saturday, November 5th, 2011 (last updated)

Before vaccines, people became immune only by actually getting a disease and surviving it. Immunizations are an easier and less risky way to become immune. Immunizations are important for adults as well as for children. Here’s why.

Miss Moxey 25

Vaccination exemptions rise in California amid concerns

Thursday, November 3rd, 2011 (last updated)

Increasing rates of unvaccinated young children with “personal belief exemptions” from vaccination requirements are becoming worrisome, according to research presented here at the American Public Health Association (APHA) 139th Annual Meeting.

Recent concern about vaccine safety appears to be gaining strength, and state regulations requiring parents to vaccinate their children before they can attend public schools vary. In California, obtaining a personal belief exemption could not be easier — parents are only required to sign their name to a 2-sentence standard exemption statement on the back of the vaccination requirement form.

In evaluating data on the rates of exemptions from the California Department of Public Health, the state’s Department of Education and the US Census, researchers found that in 2010, the state had about 11,500 kindergartners with personal belief exemptions, representing a 25% increase over the previous 2 years.

The increasing rate indicates that, for kindergartners who have adhered to vaccination schedules, exposure to children with personal belief exemptions is about 2.3 per 100 children.

Because children with the exemptions tend to be found in clusters, the rate of children with exemptions who are exposed to other children who also have exemptions — a higher-risk combination — was 15.6 per 100 in 2010, said lead author Alison Buttenheim, PhD, MBA, from the University of Pennsylvania’s Robert Wood Johnson Health & Society Scholars Program in Philadelphia.

“The average kindergartner with a personal belief exemption attends a school where the exemption rate is 15 per 100, and we see that figure increasing all the time,” she reported.

Previous data from the fall of 2008 showed that 10% of the nearly half-million kindergartners in California attended schools where personal belief exemption rates exceeded 5%, and as many as 61% of kindergartners with 1 or more personal belief exemptions (n = 9196) attended schools where the personal exemption rate exceeded 5%. Among those, a third attended schools where the personal belief exemption rate exceeded 20%.

In a separate study conducted by the same team, the researchers investigated the concerns that parents have about vaccines by evaluating data on the specific vaccines received by 168 patients at a pediatric practice in Philadelphia where the practitioner, though pro-vaccine, is known to accommodate parents who seek alternative vaccination options.

Although not necessarily indicative of the larger population, the results give a snapshot of the types of issues that may underlie vaccination concerns. The results indicated that as many as 40% of parents had more than one concern.

The leading concern was that the vaccines “overtax” the immune system (16%). “This was commonly expressed as the parents feeling the schedule just represented too many shots that could overburden the system,” Dr. Buttenheim said.

Other reasons for concern included the rarity of vaccine-preventable diseases (10%), a preference for natural immunity (7%), and autism (5%).

Dr. Buttenheim noted that increasing rates of personal belief exemptions have coincided with sharp increases in measles cases.

“Measles cases were very low in the US until 2008, when rates jumped up. Things calmed down again but then they jumped up again in 2010. We are very close to 200 cases in the US this year…. Meanwhile, this a disease that we thought we had eradicated,” she said.

Medscape Medical News

Study suggests obesity hinders influenza vaccine

Tuesday, November 1st, 2011 (last updated)

A new study suggests that overweight people benefit less from the flu vaccine than those of normal weight, and the heavier they are, the lower their immune response to the shot over time.

Researchers studied 74 people given the combination vaccine against three strains of influenza (flu) in the 2009-10 season, measuring their antibody response one month after getting the shot and then a year later. A third of the group were of normal weight, a third overweight and a third obese. Most were women.

After one month, overweight people had produced about the same level of antibodies as those of normal weight. But 11 months later, more than half of the obese patients had a fourfold or greater decrease in antibodies, a drop seen in just 25 percent of the normal-weight subjects.

The study, published online last week in The International Journal of Obesity, found that the activity of CD8+ T cells, white blood cells that help fight flu infection, also decreased as body mass index increased.

The study is continuing in an effort to determine whether body mass index correlates with actual rates of laboratory-confirmed influenza in people who have been vaccinated.

“We have stronger flu vaccines for elderly populations, because their immune response is not as robust,” said the senior author, Melinda A. Beck, a professor of nutrition at the University of North Carolina. “Maybe we need stronger vaccines for obese people as well.”

The International Journal of Obesity