Archive for April, 2011

Study shows were parents get information about vaccines

Monday, April 4th, 2011 (last updated)

A new study by researchers from the University of Michigan shows that most parents get their information about vaccines from their child’s doctor, but that some also listen to public health officials, other parents, friends, family and even celebrities.

In a new study published in the journal Pediatrics, researchers determined how much parents trust different sources of information when it comes to vaccines. It is believed that this information can then be used in an effort to determine what disseminating methods would be most effective in providing evidence-based information to parents.

“We know from this national study that parents get information about children’s vaccines from many sources,” Gary L. Freed, professor of pediatrics at the University of Michigan, said. “But the source trusted most by parents for vaccine-safety information is their children’s doctor, which is consistent with the results of several previous studies.

“Researchers surveyed over 1,500 parents of children under the age of 17. The parents were asked to rate their degree of trust in sources of vaccine information as “a lot,” “some,” or “none.”

The majority of parents – 76 percent – surveyed indicated that they trusted their child’s doctor “a lot.” Health care providers were trusted “a lot” 26 percent of the time and government vaccine experts were trusted “a lot” 23 percent of the time.

 Family and friends were trusted “some” by 67 percent of respondents, and parents who believe their child was harmed by a vaccine were trusted “some” by 65 percent of respondents. Celebrities were trusted “a lot” for vaccine-safety information by two percent of the respondents and “some” by 24 percent.

“Those who design public health efforts to provide evidence-based information must recognize that different strategies may be required to reach all groups of parents,” Freed said. “Even if only a fraction of parents receive, believe, and act on misinformation about vaccine safety provided by these different sources, individual children’s health and the population’s health may suffer because of vaccine preventable illnesses.”

New vaccine developed to treat norovirus infections

Monday, April 4th, 2011 (last updated)

Scientists at Ohio State University have tested an experimental vaccine against the human norovirus, which is the cause of around 90 percent of highly contagious non-bacterial illnesses, demonstrating that the vaccine generates a strong immune response in mice.

The scientists used a novel viral vector-based method to grow and deliver the vaccine, which has also been effective in fighting hepatitis C and HIV infections. The animals that received the vaccine received a robust white blood cell response, high levels of antibodies and an additional immune response in the gastrointestinal system.

“The mice in our study developed a much higher antibody response to our vaccine candidate than they did to a more traditional vaccine,” Jianrong Li, assistant professor of food science and technology at Ohio State and the senior author of the study, said. “That’s one of the keys, to have a sustained antibody response, so that when the disease comes along, you can neutralize the virus and protect yourself.”

The researchers said that these results support the use of viral vector-based techniques as a new and effective way to develop vaccines for human norovirus and other viruses that cannot be grown in cell cultures. In particular, a safe vaccine against norovirus might prevent millions of gastrointestinal illnesses every year in the United States.

Using the vesicular stomatitis virus, also known as VSV, to create a recombinant virus for a norovirus vaccine led to close to 25 times higher levels of antibodies induced when compared to traditionally prepared vaccine candidates. “This might be the most important advantage of the VSV-based norovirus vaccine candidate – it prepares a high concentration of norovirus-specific antibodies that can assist with virus detection, disease diagnosis and therapy,” Li said.

Dramatic rise in measles cases in Europe

Saturday, April 2nd, 2011 (last updated)

Measles is a potentially severe disease that can be prevented by an effective and safe vaccine. When given in two doses, at least 98% of those receiving the vaccine are protected against the disease. All countries of the European Region of the World Health Organization, including the EU/EEA countries, are committed to eliminate measles by 2015.

Since the end of 2008, France is facing increased continuous indigenous circulation of measles across the country (more than 10,000 reported cases including five deaths) with a recent explosion of cases reported in the first months of 2011 (Figure 1). In January and February 2011, there were 3,749 cases notified in the country compared with 5,021 cases in 2010 and 1,544 cases in 2009 (provisional data for 2010 and 2011).

From October 2010 through February 2011, the most affected French Regions were Rhône-Alpes (incidence rate: 44 cases per 100,000 inhabitants), Franche-Comté (22/100,000), Languedoc-Roussillon (19/100,000), Provence-Alpes-Côte d’azur (13/100,000) and Auvergne (11/100,000).

There was also a surge in new cases in Danish adults at the beginning of the year, with public health authorities in Switzerland subsequently reporting a sudden increase. Norwegian authorities have also expressed concern at a spike in childhood measles reported in recent weeks.

Parts of northern Europe have sub-optimal vaccination coverage, according to the ECDC. The UK, France, Italy, Ireland, Austria and Belgium all have (one-dose) MMR immunization rates below 90%, according to EU stats, and experts say the second dose is often missed.

Reseachers find promising target for AIDS vaccine

Friday, April 1st, 2011 (last updated)

According to research by scientists at the Dana-Farber Cancer Institute, a section of the protein envelope of the AIDS virus once believed to be an unlikely target for a vaccine may be one of the most promising.

The section, called the V3 loop, is a twisting strand of protein that is an attractive vaccine target because immune system antibodies aimed at the loop could offer protection against multiple HIV-1 genetic subtypes. Offering protection against different subtypes is key because of how rapidly the viruses mutate.

The investigators injected a monoclonal antibody – a preparation of millions of identical virus fighting antibodies – into Asian monkeys called macaques. The antibody was from a person infected with a specific clade or particular genetic subtype. The macaques were then exposed to a virus from a different clade, which protected all the treated monkeys from infection from the monkey form of HIV-1. All of the exposed monkeys without the antibody were heavily infected.

“This is the first time a monoclonal antibody made against an AIDS virus of one clade has provided complete protection against an AIDS virus of a different clade in animal models,” Ruth Reprecht, the study’s senior author, said. “Previous studies have shown that such neutralizing antibodies can protect macaques from infection within one clade; but as more clades of the AIDS virus evolve, it has been unclear whether such antibodies could shield across different clades and prevent infection. Now we have an answer.”

The study has provided some vindication for the V3 loop as a target for the immune system as many scientists have thought the protein strand was a decoy due to its rapid mutation. The researchers hope to find a way to focus the body’s immune system responses to the small portion of the V3 loop that is shared by viruses of different clades. This would enable the body to generate its own protective antibodies to fight the virus.