Archive for January, 2013

Pediatric rotavirus vaccination indirectly protects unvaccinated adults

Wednesday, January 30th, 2013 (last updated)

Pediatric rotavirus vaccination also indirectly protects unvaccinated adults from the highly contagious cause of severe diarrhea and vomiting, suggests a new study published in Clinical Infectious Diseases and available online. The findings suggest pediatric immunization against the virus may be more cost effective than previously thought, given rotavirus-related health care costs among adults.

Before the vaccine, rotavirus caused an estimated 24 million outpatient visits, 2.4 million hospitalizations, and 453,000 deaths in infants and young children worldwide each year. Following the introduction of the pediatric rotavirus vaccine in the United States, declines in the disease have been seen in both vaccinated and unvaccinated children.

Evan J. Anderson, MD, now at Emory University, and a team of researchers at Northwestern Memorial and Children’s Memorial Hospitals in Chicago looked into whether the vaccine’s benefits extended to unvaccinated adults. They compared the prevalence and genotypes of rotavirus in stool samples collected from approximately 3,500 adults before widespread implementation of pediatric rotavirus vaccination (2006-2007) with the prevalence in samples collected from 2008 to 2010. The researchers found the number of unvaccinated adults who had rotavirus was almost halved in the years after the vaccine was introduced for use in children in the U.S.

“In adults with diarrhea who see the doctor and who have testing for bacterial infections, we noticed an almost 50 percent decrease in rotavirus,” said Dr. Anderson. With previous research estimating $152 million in total adult inpatient hospital charges related to rotavirus each year in the U.S., this latest data may make pediatric vaccination “much more cost effective than previously believed.”

Dramatic declines in rotavirus prevalence were evident in both adults admitted to the hospital and in those treated as outpatients. The findings suggest that “vaccinating children can protect adults from rotavirus by decreasing the amount of rotavirus circulating in the community,” Dr. Anderson said. Because rotavirus genotypes change from year to year, the researchers also noted that “ongoing surveillance is needed to determine whether this impact is sustained.”

The positive effect of pediatric rotavirus vaccination programs on the prevalence of disease among both young and old, vaccinated or not, underscores the need to support and encourage vaccination, Dr. Anderson said. “By improving the health of children, we indirectly improve the health of adults.”

Source:
News Medical

The value of vaccines: reported measles cases in the US

Tuesday, January 29th, 2013 (last updated)

MISCONCEPTION: Diseases had already begun to disappear before vaccines were introduced, because of better hygiene and sanitation.

Statements like this are very common in anti-vaccine literature, the intent apparently being to suggest that vaccines are not needed. Improved socioeconomic conditions have undoubtedly had an indirect impact on disease. Better nutrition, not to mention the development of antibiotics and other treatments, have increased survival rates among the sick; less crowded living conditions have reduced disease transmission; and lower birth rates have decreased the number of susceptible household contacts. But looking at the actual incidence of disease over the years can leave little doubt of the significant direct impact vaccines have had, even in modern times. Here, for example, is a graph showing the reported incidence of measles from 1950 to the present.

The value of vaccines: reported measles cases in the US

There were periodic peaks and valleys throughout the years, but the real, permanent drop in case of measles in the U.S. coincided with the licensure and wide use of measles vaccine beginning in 1963. Graphs for most other vaccine-preventable diseases show a similar pattern. Are we expected to believe that better sanitation caused incidence of each disease to drop, just at the time a vaccine for that disease was introduced?

Source:
CDC

Alcoholism vaccine will give drinkers an immediate hangover if they drink even a small amount of booze

Monday, January 28th, 2013 (last updated)

A new vaccine will give anyone who drinks even a small amount of alcohol an immediate and very heavy hangover.

Scientists from the University of Chile have spent a year designing the drug in a bid to tackle the growing problem of alcoholism in the country.

The vaccine, which would be effective for between six months and a year, works by sending a biochemical message to the liver telling it not to express genes that metabolise alcohol.

Normally, the liver turns alcohol into the hangover-causing compound called acetaldehyde which is then broken down by a metabolising enzyme.

If someone who’s been vaccinated tries to drink alcohol, they will immediately experience severe nausea, accelerated heartbeat, and general discomfort.

Once the vaccine has been administered it cannot be reversed.

A preclinical trial using mice to determine the correct dosing is due to begin next month with researchers hoping to begin tests on human subjects in November.

Dr. Juan Asenjo, director of the university’s Institute for Cell Dynamics and Biotechnology said while the vaccine is not a cure-all, it could provide an important first step.

He told the Santiago Times newspaper: ‘People who end up alcoholic have a social problem; a personality problem because they’re shy, whatever, and then they are depressed, so it’s not so simple.

‘But if we can solve the chemical, the basic part of the problem, I think it could help quite a bit.

‘In Chile, according to the most recent 2011 study from the World Health Organization, one in 15 men have an alcohol use disorder.

Dr Asenjo belives the vaccine has the potential to help millions of people worldwide.

He added: ‘If it works, it’s going to have a worldwide impact, but with many vaccines one has to test them carefully. I think the chances that this one will work are quite high.’

Alcoholism vaccine

Source:
Daily Mail Online

The journey of your child’s vaccine

Monday, January 28th, 2013 (last updated)

Before a new vaccine is ever given to people, extensive lab testing is done that can take several years. Once testing in people begins, it can take several more years before clinical studies are complete and the vaccine is licensed.

The journey of your child’s vaccine

Source:
CDC

GAVI praises exclusion of vaccine preservative from ban

Saturday, January 26th, 2013 (last updated)

The GAVI Alliance expressed its praise on Friday for the U.N.’s decision to recognize the safety of a mercury-based vaccine preservative by excluding it from a list of banned substances in a mercury treaty.

Delegates at the United Nations Environment Program specifically included thimerosal, a widely used vaccine preservative, as an exception in a treaty on the release of mercury into the environment. Allowing thimerosal to count as an exception in the treaty was endorsed by the World Health Organization, UNICEF, GAVI and other civil organization societies.

Thimerosal has been used widely since the 1930s to prevent fungal and bacterial contamination of multi-dose vials of vaccines. Of 2.5 million deaths prevented annually through vaccines, 1.4 million are prevented using thimerosal-preserved vaccines.

Because thimerosal contains small amounts of ethylmercury, it was included in UNEP treaty negotiations. The negotiations were meant to rid the planet of risks posed to human health and the environment from mercury.

Unlike methylmercury, which can move through the food chain and accumulate in the body, ethylmercury is broken down by the body and flushed out within a few days.

The treaty specifically excludes vaccines containing thimerosal as a preservative and focuses on restricting major sources of environmental mercury releases.

More than 140 countries and 900 delegates were involved in the final negotiations to protect access to vaccines.

Source:
Vaccine News Daily

Give HPV vaccine to gay men to reduce anal cancer

Saturday, January 26th, 2013 (last updated)

The British Medical Association has urged the government to give the human papillomavirus (HPV) vaccine to gay men.

Colm O’Mahony and Penelope Toff of the BMA wrote to health minister Anna Soubry about protecting gay men against the sexually transmitted disease.

They asked that the government introduce a vaccination programme for gay men to reduce the number of anal and mouth cancer cases.

The HPV vaccine is currently given to teenage girls as it reduces the risk of developing cervical cancer in later life. HPV is the most common cause of cervical cancer, which killed 936 women in 2010.

It was introduced in 2008 for girls aged 12 and 13. It is thought it will save around 400 lives every year.

In September last year, Gardasil was replaced with Cervarix as the HPV vaccine. Gardasil is highly effective in protecting against two strains of HPV that cause 90 percent of genital wart cases and 70 percent of cervical cancer cases.

After the vaccination was introduced to girls in Australia, there was a significant drop in the number of men suffering from genital warts, which was the result of the “herd immunity effect”, O’Mahony and Toff said.

However, the number of HPV cases among MSM (men who have sex with men) has increased dramatically, they said.

They wrote: “The increasing incidence of HPV and development of anal lesions in gay men, particularly HIV positive gay men, is alarming.

“As doctors of this cohort, we need to be sensitive to any factors that could impact on individuals being able to protect themselves and work towards protecting them from acquiring infections at an early age.

“We believe that a vaccination programme with Gardasil which included this group would be of enormous benefit in reducing the increasing incidences of anal warts, anal pre-cancers and cancers, as has been borne out in Australia.

“Infection with high-risk types of HPV causes more than 80 percent of anal cancer. During the last 20-30 years the incidence of anal cancer has been increasing. Incidence of anal cancer is highest in MSM who are about 20 times more likely than heterosexual men to develop the disease.

“HIV positive men are at even greater risk with evidence that rates are increasing despite the introduction of effective antiretroviral therapy from 1996 onwards,” the letter said.

They also note that research now shows that a strain of HPV also causes many oropharyngeal cancers (mouth cancer).

James Taylor, senior health officer at lesbian, gay and bisexual charity Stonewall, said: “We support the BMA’s announcement on an HPV vaccine in principal, although it’s clear there’s still research to be done on the effectiveness of the proposal.

“Research published by Stonewall last year highlights the shocking levels of discrimination many gay and bisexual men experience when accessing healthcare, which impacts on whether gay and bisexual men take advice on testing and monitoring services.”

O’Mahony and Toff accept it would not be economically viable in the UK at present, so suggest another means of protecting MSM.

As a result, they recommend a vaccination programme among gay men, it would be easy to have it as an “add-on” vaccination for those being vaccinated with Hepatitis B.

Taylor added: “It’s clear the NHS needs to rethink how it approaches many of its patients, as well as telling gay and bisexual young men what they need to know about safe sex and same-sex relationships in the school curriculum.”

Source:
International Business Times

A global ban on thiomersal in vaccine manufacturing: stick with the science

Friday, January 25th, 2013 (last updated)

Government representatives are meeting in Geneva this week to decide whether to introduce a global ban on mercury that could include thiomersal, a mercury-based preservative that has been used in some vaccine manufacturing since the 1930s to prevent bacterial or fungal contamination of multidose vials of vaccine.

Hosted by the United Nations Environment Program, the intergovernmental negotiating committee is charged with drafting a global treaty to rid the world of the threats posed by mercury.

Despite the ominous connotations of mercury, the decision should in theory be a no-brainer: The scientific and medical consensus is that thiomersal poses no human health risk, and that rather than saving lives, a ban would put millions of the world’s poorest children at risk of deadly diseases by disrupting vaccination programs.

But with vaccines, logic and evidence don’t always prevail. In the late 1990s we were at a similar juncture when, as part of a broader remit to find ways to reduce the human health hazards posed by mercury and under pressure from anti-vaccine lobbyists, the U.S. Food and Drug Administration turned its attention to the safety of thiomersal (known in the U.S. as thimerosal).

Despite a lack of evidence that it was harmful — and in the absence of any evidence to show that it wasn’t — the F.D.A. decided to take a precautionary approach and urged manufacturers to reduce or eliminate thiomersal from almost all vaccines in the United States.

Since then, scientists have published unequivocal evidence of its safety, including a 2006 study which showed that thiomersal is broken down by the body into ethylmercury. Unlike methylmercury, say from contaminated fish, which can make its way through the food chain and accumulate in the body, ethylmercury is naturally flushed out of the body within a couple of weeks. Despite such clinical and laboratory evidence, the damage to thiomersal’s reputation had already been done, and anti-vaccine campaigners are still trying to fan the flames.

Anti-vaccination groups have long campaigned against the use of thiomersal, claiming that this organic mercury derivative was responsible for increases in developmental disorders such as autism. What’s more, they argue that with a precautionary reduction already in place in the United States, denying children in developing countries access to the same thiomersal-free vaccines would be a global injustice.

Nothing could be further from the truth. Quite apart from the mountain of scientific evidence refuting any link between thiomersal and autism, with some studies involving hundreds of thousands of children, banning thiomersal or phasing out this agent would have a devastating impact on global health and lead to millions of children being denied access to life-saving vaccines.

To some extent, thiomersal is still used in vaccines in the United States and Europe, for example in some flu shots, but if there were a ban we could easily switch to single-dose vials.

In developing countries this is not so simple. Not only are single-dose vials less cost effective and less practical for mass vaccinations, they also take up more space in refrigerators, which are already at peak storage capacity. In the absence of any alternative preservative, far fewer vaccines would reach children in developing countries.

This would be a tragedy. In 2010 alone it is estimated that more than 1.4 million child deaths were prevented through the use of thiomersal-containing vaccines. Little wonder that organizations such as the World Health Organization, Doctors Without Borders, the American Academy of Pediatrics, the U.S. Institute of Medicine and the GAVI Alliance oppose a ban.

Indeed thiomersal is not the main target of the anti-mercury treaty, but rather an unfortunate bycatch. Even so, in many ways the situation mirrors the debate that took place more than a decade ago. This time it is the U.N.E.P. that is undertaking the laudable task of reducing the human health impact of mercury. The problem is that under pressure from anti-vaccine groups, hard scientific evidence is sometimes disregarded.

A recent example of this took place in December in a French case involving a claim by a former state employee that the aluminum content of vaccines given to him at work made him chronically ill. Although the court was not convinced of a probable link between the man’s illness and vaccinations, and in the absence of any scientific evidence of a link or any other explanation, it ruled in favor of the employee.

That is not to say that taking precautions isn’t intrinsically sensible; it’s just that sometimes dodging the issue in this way is not the best precaution, and instead of solving problems it sometimes creates them.

One of the core principles of medicine is “primum non nocere”: first, do no harm. But given the sheer numbers of lives at stake there is a strong argument that the burden of proof be shifted to the detractors.

Where a vaccine already has an established and strong safety record and is saving lives, the onus should be on producing evidence of a genuine risk before there is any change in policy related to its availability.

With millions of vulnerable lives at stake, the treaty negotiators need to engage and recognize that a ban on thiomersal would be bad policy based on bad science.

Source:
The New York Times (by Seth Berkley)

Researchers close enough to developing vaccine against Leishmaniasis

Wednesday, January 23rd, 2013 (last updated)

A recent report talks about how researchers are trying to develop a vaccine which might be able to protect one from a lethal infectious parasite. In the name of Visceral leishmaniasis, the parasite killer is being treated harsh enough just after malaria.

It has been made clear by the team from The University of Western Australia that the parasite actually passes to organs such as liver, spleen and bone marrow, and there are potential chances of claiming one’s life if not being dealt at right time.

Backed by researchers from India, Brazil, UK, Australia and the USA, UWA Winthrop Professor Jenefer Blackwell, Head, Genetics and Health, Telethon Institute for Child Health Research, managed to track down main region of the major immune response locus, which is reported as the major histocompatibility complex (MHC), which is apparently treated as the key factor behind the disease.

“Earlier genetic studies of visceral leishmaniasis in inbred mice allowed us to clearly demonstrate the importance of the MHC in regulating this disease”, said the lead author in Nature Genetics.

If reports are to be believed, there are as many as 12 million people affected by the same, with as much as estimated 1.5 million new cases annually are reported especially in India, Bangladesh, Nepal, Sudan, South Sudan, Ethiopia and Brazil.

Researchers close enough to developing vaccine against Leishmaniasis

Source:
FrenchTribune.com

Helping developing countries fight malaria – QIMR’s Infectious Disease Research Program

Tuesday, January 22nd, 2013 (last updated)

QIMR researchers are looking for ways to control and prevent malaria, by attacking either the parasite that causes the disease or the mosquito that spreads it.

Researchers at the Queensland Institute of Medical Research have developed a method to conduct clinical trials to test new antimalarial drugs. We are currently trialling new treatments and therapies to stop the Plasmodium (malaria) parasite from causing disease.

We are also working towards a vaccine against malaria. If a malaria vaccine can be developed, this will stop the burden of this disease in countries like Africa, where a child dies every minute from malaria.

IOM confirms safety of childhood vaccine schedule

Monday, January 21st, 2013 (last updated)

Despite scientific evidence and confirmation from the Centers for Disease Control and Prevention (CDC) that childhood vaccines help rather than hurt, some parents still harbor doubts about immunizing their kids. A recent study from the Institute of Medicine further underscores the safety of the federal childhood immunization schedule

The 14 committee members who looked into the issue acknowledged that vaccines carry some risks — like any medication or intervention — but found that the benefits outweigh those concerns.

“In this most comprehensive examination of the immunization schedule to date, the IOM committee uncovered no evidence of major safety concerns associated with adherence to the childhood immunization schedule, which should help to reassure a diverse group of stakeholders,” the report says. “Indeed, rather than exposing children to harm, following the complete childhood immunization schedule is strongly associated with reducing vaccine-preventable diseases.”

The report, sponsored by the U.S. Department of Health and Human Services (HHS), addressed the childhood immunization schedule established for children 6 and younger by the Advisory Committee on Immunization Practices. The schedule is designed to protect against 14 pathogens.

Although about 90 percent of children receive most of the recommended vaccines by the time they enter kindergarten, the remaining 10 percent either receive vaccines on an alternate schedule or do not receive any vaccinations at all.

In that latter group, parental concerns about vaccination and potential side effects are driven largely by the number of immunizations required in the first years of life.

The childhood immunization scheduleClick here

Source:
ABCNews