Archive for 2011

Interview with Jonas Salk, developer of the polio vaccine

Sunday, December 11th, 2011 (last updated)

Jonas Salk (October 28, 1914 – June 23, 1995) was an American medical researcher and virologist best known for his discovery and development of the first safe and effective polio vaccine. Until 1955, when the Salk vaccine was introduced, polio was considered the most frightening public health problem of the post-war United States. Annual epidemics were increasingly devastating. The 1952 epidemic was the worst outbreak in the nation’s history. Of nearly 58,000 cases reported that year, 3,145 people died and 21,269 were left with mild to disabling paralysis, with most of the victims children.

Day at Night was a popular public television series hosted by James Day. The series features fascinating interviews with notable cultural and political figures conducted in the mid 1970’s. The interview with Jonas Salk dates April 28, 1974.

Source:
CUNY TV, the non-commercial cable television station of the City University of New York.

Intranasal Norovirus demonstrating clinical efficacy

Saturday, December 10th, 2011 (last updated)

Norovirus causes cramping, diarrhea and vomiting, and spreads easily from person to person, often in crowded, closed places like cruise ships. Each year, 21 million cases of norovirus occur in the United States, according to background information in the small new study published in the Dec. 8 issue of the New England Journal of Medicine.

“It is possible to prevent infection and illness with a vaccine for norovirus,” said Dr. Robert Atmar, a professor of medicine and molecular virology at the Baylor College of Medicine in Houston. But many questions remain unanswered, he said. For example, “we have to figure out the best way to give it and how long protection lasts.”

The new study included 98 people who received the vaccine or an inactive placebo. All of the participants tested positive for a gene that makes them more susceptible to the norovirus, the FUT2 gene.

Those who received the new vaccine were less likely to develop the stomach bug than their counterparts who received the placebo, the study showed. What’s more, they were also affected by the bug less frequently than their counterparts who did not receive the vaccine. Of recipients, 70 percent of people responded to the vaccine as evidenced by antibody levels in their bloodstream.

The new vaccine is given as two doses three weeks apart via a nasal spray. There were no safety issues seen in the new study. Side effects included stuffy nose and sneezing and were equally likely to occur in those who received the placebo. The new study was supported in part by LigoCyte Pharmaceuticals, maker of the vaccine.

Source:
USA Today & New England Journal of Medicine & Vaccinenation

Intranasal vaccine effective against Norwalk virus illness

Wednesday, December 7th, 2011 (last updated)

Two doses of an intranasal virus-like particle (VLP) vaccine, containing the  adjuvants chitosan and monophosphoryl lipid A, protect healthy adults against Norwalk virus, study results published in the Dec. 8 issue of the New England Journal of Medicine indicate.

Robert L. Atmar, MD, of Baylor College of Medicine in Houston, and colleagues assessed the vaccine’s safety, immunogenicity and efficacy in preventing acute viral gastroenteritis after challenge with a homologous Norwalk virus strain, genotype GI.1. A total of 90 healthy adults (aged 18 to 50 years) were randomly assigned to receive two doses of vaccine (47 participants) or placebo (43 participants). Eighty-four of the participants were subsequently inoculated with Norwalk virus and were monitored for infection and symptoms; 77 of these patients were included in the per-protocol analysis.

Vaccination significantly reduced the frequency of Norwalk virus gastroenteritis and infection, the researchers found, with 69% of placebo recipients experiencing gastroenteritis vs. 37% vaccine recipients. Norwalk virus infection occurred in 82% vs. 61% for placebo and vaccine recipients, respectively. Overall, 70% of people in the vaccination group showed a Norwalk virus-specific IgA seroresponse.

Adverse events were similar among patients in the vaccination and placebo groups, with nasal stuffiness, nasal discharge and sneezing among the most commonly reported symptoms after vaccination.

“This study shows that it may be possible to use a vaccination strategy to prevent norovirus disease.,” the authors wrote.

Source:
The Clinical Advisor & New England Journal of Medicine

Scientists have developed a vaccine that protects mice against a deadly form of the Ebola virus.

Tuesday, December 6th, 2011 (last updated)

First identified in 1976, Ebola fever kills more than 90% of the people it infects.

The researchers say that this is the first Ebola vaccine to remain viable long-term and can therefore be successfully stockpiled.

The results are reported in the journal Proceedings of National Academy of Sciences.

Ebola is transmitted via bodily fluids, and can become airborne. Sufferers experience nausea, vomiting, internal bleeding and organ failure before they die.

Although few people contract Ebola each year, its effects are so swift and devastating that it is often feared that it could be used against humans in an act of terrorisme.

All previously developed vaccines have relied on injecting intact, but crippled, viral particles into the body.

Long-term storage tends to damage the virus, paralysing the vaccine’s effectiveness.

The new vaccine contains a synthetic viral protein, which prompts the immune system to better recognise the Ebola virus, and is much more stable when stored long-term.

The vaccine protects 80% of the mice injected with the deadly strain, and survives being “dried down and frozen,” said biotechnologist Charles Arntzen from Arizona State University who was involved in its development.

He said the next step is to try the vaccine on a strain of Ebola that is closer to the one that infects humans.

Source:
BBC News & PNAC

HPV vaccination program in schools

Sunday, December 4th, 2011 (last updated)

Recent research into the school-based HPV vaccination program suggests there is a lack of understanding surrounding the vaccine, with some girls frightened of receiving the injection. Similar issues in the UK have caused a school to withdraw the program. We speak to research associate Spring Cooper who works in Paediatrics & Child Health at Sydney University to find out what can be done to ensure the same does not happen in Australia.

Source:
6 minutes video

Lab mice point way to HIV vaccine

Thursday, December 1st, 2011 (last updated)

Tests on lab mice have opened up a new path towards a vaccine against HIV, one of the most frustrating quests in the 30-year history of AIDS, scientists have reported.

Genetically modified mice fought back the human immunodeficiency virus (HIV) after they had been injected with genes to make antibodies, the first line of defence in the immune system, the report said in the journal Nature.

First identified in 1981, AIDS has claimed at least 25 million lives, although the annual toll is falling sharply from the peak of the pandemic in response to drug treatment.

But AIDS campaigners say the pandemic will only be crushed once a vaccine emerges. So far, in clinical trials, only one candidate formula has had even a modest effect, providing a shield of only 31 percent against the risk of HIV infection.

This has prompted researchers to return to the drawing board, to look for “broadly neutralising antibodies” – Y-shaped proteins that are the immune system’s foot soldiers – among the tiny number of people with an innate ability to resist HIV.

So far, this trawl has turned up around 20 so-called “bNAbs,” but there are big unknowns as to how they work and, if so, whether they can be made into a deliverable vaccine.

Delving into this, a team led by David Baltimore at the California Institute of Technology (Caltech) says it has developed a way to deliver bNAb-making genes to lab mice.

The rodents were engineered to carry human cells that allow HIV to penetrate and reproduce.

The approach, called Vectored Immuno Prophylaxis, or VIP, entails using a harmless virus as a “Trojan horse” in which they tucked the genes able to turn out specific bNAbs.

They then injected the virus into the leg muscles of the mice, where it holed up in cells, enabling the bNAb genes to produce antibodies in response to HIV.

The mice were first challenged with just one nanogram of AIDS virus – enough to infect most non-treated mice that received it – but the dose was eventually cranked up to 125 nanograms without problems. There were no signs of any side effects.

“VIP has a similar effect to a vaccine but without ever calling on the immune system to do any of the work,” said Alejandro Balazs, lead author of the study, in a press release issued by Caltech.

“Normally, you put an antigen or killed bacteria or something into the body, and the immune system figures out how to make an antibody against it. We’ve taken that whole part out of the equation.”

The team stressed that the jump from mice to humans is large.

“We’re not promising that we’ve actually solved the human problem,” said Baltimore. “But the evidence for prevention in these mice is very clear.”

He added the team was drawing up plans to cautiously test the method in small-scale human clinical trials.

Source:
Nature & The Australian

ECDC publishes the monthly measles monitoring report for October 2011

Sunday, November 27th, 2011 (last updated)

Since the last European monthly measles monitoring report (EMMO) published on 18 October, over 1 000 new measles were detected in the EU and EEA/EFTA countries. This brings the total number of cases in 2011 to more than 30 200.

No new measles outbreaks were reported from EU and EEA/EFTA countries during October 2011. Two cases of subacute sclerosing panencephalitis (SSPE), one of whom died, were reported in October 2011. SSPE is a late fatal complication of measles infection.

Measles, a highly infectious vaccine-preventable disease, is re-emerging in Europe. Countries within the European Region of the World Health Organization, which include EU and EEA/EFTA countries, have committed to eliminate measles by 2015. Elimination of measles requires sustained vaccination coverage above 95% with two doses of a measles-containing vaccine (MCV).

ECDC is monitoring measles transmission in these countries and produces epidemiological updates. The EMMO aims to provide timely public updates on the measles situation in Europe for effective disease control measures, and in support of the common 2015 measles elimination target.

In September 2011, the coordination of surveillance of measles and other vaccine-preventable diseases was transferred from the Statens Serum Institut in Denmark (the former EUVAC.NET hub coordinator) to ECDC; the EUVAC.NET website migrated to ECDC and is now maintained and moderated by ECDC. In October the EUVAC.NET Forum was replaced by EPIS–VPD, an ECDC-moderated platform for the rapid exchange of confidential information on vaccine-preventable diseases.

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Viewpoint: Pox by post: anti-vaccine moms are the new bioterrorists

Friday, November 25th, 2011 (last updated)

Would you swap spit with a stranger you know has a disease linked to severe skin infections, pneumonia, swelling of the brain and, in some cases, flesh-eating disease and death?

The latest rash of parents sending chicken pox-infected lollipops or “pox packages” through the mail shows the irrational and dangerous extremes to which parents will go to avoid vaccinating their children.

These pox-swappers connect on Facebook and online parenting forums to request saliva, infected lollipops and clothing from other families in the hope of immunizing their children the “natural” way. But the only thing that the anti-vaccine mob seems immune to is common sense.

Not only are these families endangering their own children, they’re also risking the herd immunity that protects us all from preventable, but potentially life-threatening diseases.

The chicken pox vaccine was first authorized for use in Canada in 1998, and like all authorized vaccines, it went through several stages of rigorous testing to ensure its safety and efficacy.

The side effects of the vaccine – typically mild fever and a rash, according to the Public Health Agency of Canada – seem trifling compared with the hundreds of blisters that attend a normal case of chicken pox.

Add to that the potentially fatal complications of contracting the virus and it’s hard to understand why people refuse to vaccinate their children, let alone give them diseased lollipops that could be coated in any number of other dangerous pathogens.

Some argue the vaccine isn’t 100-per-cent effective at preventing future cases of chicken pox, but neither is contracting the virus.

The difference is that those vaccinated people who do get chicken pox later experience much less severe symptoms than unvaccinated people.

Deaths from chicken pox have plummeted since the vaccine was introduced in Canada. The most recent data indicate only six deaths occurred between 2000 and 2005. Previously, that many deaths occurred each year.

Meanwhile, allowing the wild virus to continue circulating reduces Canadians’ herd immunity. Herd immunity rests on the principle of safety in numbers; if more people in a population are immune to a certain virus, more people, even those who aren’t immune, are protected from the disease.

Population-wide immunity is crucial to protecting vulnerable people who, for medical reasons, are unable to receive the vaccine.

Transporting viruses is highly regulated in North America for this reason and people who flout these laws for their own selfish reasons are arguably engaging in bioterrorism.

A commenter on the Mothering.com forum tried to warn her pox-posting compatriots that “one of the mail workers in between both of you could be (immune) compromised” and contact with the virus could be “very bad for them (and might) even kill them.”

But of course, mommy knows best. Another poster on the forum snapped back that the virus would be “completely sealed” in a plastic baggie and therefore pose no risk “unless they hacked into the package.”

What’s really scary is that it’s not just chicken pox these parents are trading – posters on some forums have also requested diseases such as measles and rubella.

It’s time Canada implement mandatory vaccination policies such as those implemented in Belgium, where polio vaccination is compulsory.

Some Canadian provinces, such as Ontario, already have policies in place that make up-to-date vaccination a requirement for public school attendance.

Enforcing these policies and instituting them countrywide could be an easy way to ensure we stamp out the real threat to our children’s health – ignorance.

Source:
Lauren Vogel – Centretown News

Delivering a Dengue vaccine: a WHO initiative helps lay the groundwork for Dengue vaccine introduction

Tuesday, November 22nd, 2011 (last updated)

In addition to developing sound evidence for informed decision-making, DVI (Dengue Vaccine Initiative) is striving to conduct policy and access related activities to create an enabling environment for the introduction of a future dengue vaccine. The World Health Organization’s Initiative for Vaccine Research (WHO IVR) is one of the DVI consortium members working towards this objective. Originally designed by the WHO and UNAIDS, the initiative is positioned within the Family and Community Health Cluster at the WHO. The unit’s mission is to accelerate the development and optimal use of safe and effective vaccines and technologies, especially in developing countries. The WHO IVR has expertise in the field of product R&D, vaccine manufacturing and regulation, vaccine clinical trial, vaccine introduction and cost-effectiveness analysis.

WHO IVR’s primary function within DVI is to lead the development of information and guidance documents, and in regulatory training activities. WHO IVR is currently preparing an information session on a dengue vaccine for the Strategic Advisory Group of Experts (SAGE) on immunization. SAGE advises the WHO on overall global policies and strategies. The information session regarding a dengue vaccine will pave the way for the development of a framework for an eventual SAGE deliberation. This will lead to the publication of a WHO Position Paper on dengue vaccines. A WHO Position Paper would substantially legitimize the call to include dengue vaccines in public vaccination programs.

Other key activities include designing a guide on the safety monitoring and post licensure evaluation of the new dengue vaccine. In conjunction with IVAC (last week’s DVI consortium member), WHO IVR will support regulatory preparedness in countries hosting dengue clinical trials and countries likely to quickly adopt the vaccine.

Given its extensive infrastructure and network of engagement with ministries of health and national immunization programs, the WHO and its Regional Offices maintain the ability to raise visibility of dengue on global, regional and country levels. This unprecedented influence will be essential to guaranteeing that the world’s most vulnerable populations have access to a future dengue vaccine.

Source:
Sabin Vaccine Institute

Immunization in teens: good news, bad news

Sunday, November 20th, 2011 (last updated)

Dr.Paul Offit, MD, asks why we are “raising a generation of girls who are susceptible to cervical cancer even when we have the technology to prevent it.”