Archive for March, 2014

The ins and outs of polio surveillance

Friday, March 21st, 2014 (last updated)

Polio is a sneaky virus. For every paralytic case, there are around 200 other individuals quietly spreading the virus. That’s why it’s crucial that surveillance systems are sensitive enough to detect any polio transmission early, before an outbreak can explode.

The backbone of polio surveillance is the investigation of cases of acute flaccid paralysis (AFP) – or, in layman’s terms, every child who reports to their health worker with the kind of limp, floppy paralysis seen in children stricken with polio. However, there are many other causes of AFP, including Guillain-Barré syndrome, traumatic neuritis, transverse myelitis, other enterovirus infections, and even snake bite. In 2013, the World Health Organization received reports of over 100,000 AFP cases worldwide, of which only 404, or less than half a per cent, were confirmed as polio. Regardless, each and every case of AFP around the world must be investigated to ensure that polio is detected wherever it still exists. Information is gathered from parents and physicians, and stool samples are tested for the presence of the virus – first, usually, in a World Health Organization (WHO)-accredited national laboratory and then in a WHO regional lab.

India’s success against polio was partly due to the sensitivity of its surveillance system. The country cast its net wide (and continues to do so), catching anything that looked even slightly like polio for analysis. With a more accurate picture of where polio was spreading and of what serotype, the country could run more efficiently targeted mass vaccination campaigns.

polio

Sometimes it isn’t so simple to gather samples, however. In times of conflict, like in Syria, for example, it is not uncommon that some cases of AFP cannot be investigated fully according to the established protocol. When laboratory specimens are not available or are inadequate, the absence of reliable laboratory results may make it difficult to either confirm the cases as polio or discard them as non-polio. In these situations the cases are ultimately reviewed by an expert committee.

But how do you detect polio even before the first case of paralysis is reported? That’s where environmental surveillance comes in. In countries most at risk of polio transmission, scientists collect sewage samples and test it for poliovirus. In Egypt, for example, environmental sampling detected the presence of wild poliovirus in December 2012. As a result, the country planned a series of vaccination rounds to protect their children from this debilitating disease and, to this day, Egypt remains polio-free.

Strong surveillance systems are, therefore, critically important to the success of global polio eradication efforts. The partner agencies of the Global Polio Eradication Initiative are committed to helping ministries of health around the world strengthen national surveillance systems – systems which will be useful in the detection of a range of diseases now and in the future, long after polio has been wiped from the face of the globe.

Source:
The Global Polio Eradication Initiative

Overcoming vaccine hesitancy

Thursday, March 20th, 2014 (last updated)

Lecture of Professor Marc Van Ranst on ‘Overcoming vaccine hesitancy’ given at the Excellence in Paediatrics congress (Doha, Qatar).

Source:
Excellence Paediatrics

Measles are back in New York City

Wednesday, March 19th, 2014 (last updated)

After more than a dozen reported cases of measles, city officials are warning unvaccinated New Yorkers to get their shots. Dr. Lisa Thebner stopped by The Couch to offer some insight into the highly contagious disease.

The health department urged New Yorkers to ensure all household members, including young children, are vaccinated against the disease. The outbreak resulted in four hospitalizations.

The city’s health department is working with local hospitals to prevent additional exposure to the virus in emergency departments. The department requested that pediatric care facilities in the Bronx and Manhattan identify and vaccinate children who have yet to receive the measles, mumps and rubella vaccine and to give the second dose of MMR to children at the next medical visit.

Adults who are unsure of their vaccination status can be revaccinated or get a blood test to determine if they are immune. Several adults who contracted measles in the recent outbreak thought they were vaccinated in the past, but they lacked the documentation.

Source:
CBS New York

Twitter crushes anti-vaccination queen Jenny McCarthy

Tuesday, March 18th, 2014 (last updated)

Jenny McCarthy asked Twitter a question: What do you look for in a mate? Twitter had one response: Someone who isn’t anti-vaccine.

You don’t need a crystal ball to see how this was going to end. On Thursday, The View co-host Jenny McCarthy asked her 1.13 million Twitter followers a question: “What is the most important personality trait you look for in a mate? Reply using #JennyAsks.” Twitter had one overwhelming response in mind: Someone who isn’t anti-vaccination like you, Jenny.

Jenny McCarthy

McCarthy, whose son was diagnosed with autism in 2005, is famous for arguing that vaccines are linked to autism in children. Though she has clarified that she “and the autism community” are not anti-vaccine per se, they are “anti-toxin and anti-schedule.” That is, she believes the standard vaccination schedule for kids is “too many too soon” and the “toxins” in vaccines (mercury, especially) cause children harm. “Isn’t it ironic, in 1983 there were 10 shots and now there’s 36 and the rise of autism happened at the same time?” she once asked Larry King. McCarthy only had anecdotal evidence from other parents to back her up but, according to her, “parents’ anecdotal information is science-based information.”

The ensuing hysteria persuaded some parents not to inoculate their kids for fear of triggering autism. And some pediatricians believe the current measles outbreak in New York City is the result of anti-vaccination activists’ fear-mongering. So, when McCarthy asked for “the most important” quality of a person you’d spend the rest of your life with, Twitter had a lot to say:

twitter

Source:
The Daily Beast

Why is the same vaccine accepted in one part of the world and rejected in another?

Monday, March 17th, 2014 (last updated)

Heidi Larson tells Fiona Fleck why communicating the benefits versus the risks of vaccination is just part of the battle to gain public confidence in vaccines.

Why is the same vaccine accepted in one part of the world and rejected in another? Click here

Source:
Bulletin World Health Organization

Study finds childhood immunizations save thousands of lives, billions of dollars

Sunday, March 16th, 2014 (last updated)

A new economic analysis of the childhood immunization schedule shows it will prevent 42,000 early deaths and 20 million cases of disease, with a savings of $13.5 billion in direct costs and $68.8 billion in total societal costs in a single cohort. The study, “Economic Evaluation of the Routine Childhood Immunization Program in the United States, 2009,” in the April 2014 Pediatrics, used population-based vaccination coverage, vaccine efficacy data, historical data on disease incidence before vaccination, and disease incidence data after vaccination to calculate the lifetime economic impact of vaccinating a hypothetical cohort of all U.S. children born in 2009. The study updates a prior analysis published in 2005. Researchers conclude that from a societal perspective, the average savings per dollar spent on vaccination is at least $10. According to the study authors, “the vaccines currently recommended for young children represent not only a major public health victory in terms of disease prevention, but also an excellent public health ‘buy’ in terms of dollars and cents.”

pediatricsClick here

Source:
American Academy of Pediatrics

Nothing, not even hard facts, can make anti-vaxxers change their minds

Saturday, March 15th, 2014 (last updated)

Vaccines save lives and make it possible to live free of the illness and disability associated with many vaccine-preventable diseases. Anti-vaccinations parents can not be convinced by scientifically proven arguments that vaccinations are safe and effective.

cartoon

Source:
ImmunizeBC

Safety of vaccines is still a tough sell with some parents

Friday, March 14th, 2014 (last updated)

When it comes to convincing wary parents that vaccinations are safe, public health officials have their work cut out for them.

A study published in the journal Pediatrics found that pro-vaccination messages may be ineffective – or could even backfire – among parents who report reluctance to have their children vaccinated. “It’s very hard to convince people using evidence when they have strong views to the contrary,” said lead author Brendan Nyhan, an assistant professor in the department of government at Dartmouth College in Hanover, N.H.

Nyhan and co-authors from the United States and the United Kingdom set out to test the effectiveness of current public-health messages designed to reduce misconceptions about vaccines and increase immunization rates for measles-mumps-rubella (MMR). They recruited a nationally representative sample of 1,756 American parents, and randomly assigned them to receive one of four different messages about vaccinations, or no message.

The pro-vaccination messages ranged from fact-based information to emotive accounts of the potential consequences for children unprotected against MMR.

One message provided evidence from the Centers for Disease Control and Prevention showing that the MMR vaccine does not cause autism. Another gave information about the dangers of measles and other diseases prevented by the vaccine. The third message showed pictures of sick children who have diseases that may be prevented by the vaccine. The fourth consisted of a dramatic narrative about an infant who almost died of measles.

In the study, however, not one of the messages appeared to sway parents who had unfavourable attitudes about vaccines. In fact, for parents most distrustful of vaccination, images of sick children with MMR diseases actually increased their reported belief that the MMR vaccine causes autism. Similarly, the narrative about an infant in mortal danger from measles increased their reported beliefs that vaccines cause serious side effects.

The findings suggest that logic does not play a major role in how people respond to public-health information about vaccines. Vaccines are a controversial topic, Nyhan pointed out, so “it’s not surprising that people respond to information about them in a way that reflects their pre-existing views.”

vaccines

In light of recent measles outbreaks in North America and Europe, however, misconceptions about the MMR vaccine are proving to be a public health hazard.

Canada’s immunization rate has been declining for a decade, dropping to 84 per cent – below the threshold to ensure population immunity. A recent report card by Unicef found that Canada’s immunization rate is lower than that of countries such as Tunisia and Eritrea.

Fears about vaccination have persisted ever since the late-1990s, when British physician Andrew Wakefield warned that the MMR vaccine causes autism. The medical community thoroughly debunked his theory, and Wakefield was stripped of his medical licence. Nevertheless, the return of measles in pockets of North America and Western Europe may be largely due to the panic Wakefield instilled in parents, whose children were never vaccinated.

Yet current public health messages designed to correct misinformation about vaccines may be counterproductive, according to the Pediatrics study. After reading correct information provided by the study, anti-vax parents said they were less convinced that the MMR vaccine causes autism – but these parents also reported reduced intentions to vaccinate their children following the message.

Nyhan theorized that, after reading the correction, these parents may have focused on other concerns about vaccines. In some cases, when confronted with the facts, “people double down on the beliefs that are challenged,” Nyhan explained.

Nyhan and co-authors cited evidence showing that parents rate their children’s doctors as the most trusted source of vaccine safety information. Nyhan acknowledged that high levels of trust in family doctors may not apply to the most hardcore anti-vaccination parents, but he identified a broader group of parents who have concerns about vaccines but are not entirely convinced vaccines are unsafe.

“Doctors could be persuasive to those people on the margins,” Nyhan said.

He added that the study results don’t imply that public health authorities should stop disseminating pro-vaccine messages. “It just means that we should try to test those messages first and learn which are more effective,” he said.

Source:
The Globe and Mail

Too many children are still unprotected: achieving immunization for all

Thursday, March 13th, 2014 (last updated)

Immunization is saving more children than ever before. Working alongside partners, UNICEF buys vaccines reaching one third of all the world’s children, but too many are still unprotected. Together, if we immunize all children with existing vaccines, we can save more than 20 million lives by the year 2020.

Source:
Unicef

Vaccine against Alzheimer tested on humans

Wednesday, March 12th, 2014 (last updated)

Vaccination against Alzheimer’s has reached the clinical trials stage and could one day prevent the pain of seeing a friend or relative facing this devastating degenerative disease.

A biotechnology company in Zaragoza, Araclon Biotech – a holding of the multinational Grifols – has developed a very advanced early-diagnosis test and, after trying out a vaccination created in response to those who test positive on rats and mice, has started testing it on human patients.

Five have so far been vaccinated out of a total of 24 at a clinic in Barcelona, the ACE Foundation, in a trial coordinated by Dr Merce Boada.

All 24 patients will be monitored to check tolerance levels to the injection over a period of 18 months – ending in around June 2015 – but it will take much longer to ascertain whether the vaccination does indeed slow down the process of Alzheimer’s.

Araclon Biotech’s scientific director, Manuel Sarasa, says the key is in prevention rather than cure, which he believes will always be impossible.

alzheimer

Of the 24 human guinea pigs, 16 are in the very early stages of Alzheimer’s and another eight will be given a placebo drug instead of the tested vaccination.

Over the next two years or so, varying doses of the vaccination will be experimented with based upon whether or not it has managed to stimulate the immune system, and procedures will be developed – Dr Sarasa believes this will include the vaccine being used on people who as yet show no signs of Alzheimer’s in order to prevent them developing it, although it is expected to be used with those who have already begun to suffer the condition to slow the process.

A further period of testing and monitoring will take at least three years, meaning it will be around the middle of the year 2020 at the earliest when it is known whether humans really can be innoculated against this debilitating condition – one which is even greater in terms of suffering for friends and family and health care workers than even the patient.

Source:
Gnomes National News Service