Archive for August, 2011

One billion children in developing countries have been vaccinated against measles since 2001

Monday, August 15th, 2011 (last updated)

The Measles Initiative today announced it has helped vaccinate one billion children in more than 60 developing countries since 2001, making significant gains in the global effort to stop measles.

The child who received the history-making measles vaccination was one of 3.5 million immunized in Mozambique this May. The immunization campaign was sponsored by the Measles Initiative’s five founding partners – the American Red Cross, United Nations Foundation, U.S. Centers for Disease Control and Prevention (CDC), UNICEF, and World Health Organization (WHO).

“When we started the Measles Initiative ten years ago, we knew that we would help save millions of lives, but we never imagined where the world’s support would take us,” said David Meltzer, senior vice president of international services with the American Red Cross. “With every dollar donated, we vaccinated another child. Across the globe, we stopped outbreaks, improved treatment and protected future generations from one of the world’s deadliest diseases. This milestone in measles control is significant and improves the overall outlook for children’s health around the world.”

In 1980, before widespread vaccination, measles caused an estimated 2.6 million deaths each year. With accelerated immunization activities spearheaded by governments and the Measles Initiative, global measles mortality has decreased by an impressive 78 percent worldwide from 733 000 deaths in 2000 to 164 000 in 2008. Reductions in measles-related deaths during that same time period accounts for nearly a quarter (24 percent) of the overall decrease in childhood mortality, representing significant progress toward Millennium Development Goal 4 (MDG4). This goal, which was set by the UN, aims to reduce the mortality rate for children less than five years by two thirds between 1990 and 2015.

“The steady march toward a measles-free world is now facing a setback,” said Dr Brent Burkholder, director of the CDC’s global immunization division. “Outbreaks in Africa, a high number of deaths in India and global funding gaps threaten the gains made in the last ten years and will hinder efforts to eradicate measles and achieve MDG4.”

The WHO estimates that waning support could result in half a million more deaths each year and erase the Measles Initiative’s gains by 2013.

Because it costs less than US$ 1 per child to vaccinate against measles, the real stumbling block is the lack of political commitment in many countries. Several economic studies, including those referenced in the Journal of Infectious Diseases July 2011 supplement, however, demonstrate that the eradication of measles is more cost effective than a control strategy and is actually cost saving for countries where measles has already been eliminated.

VaxTrak: iPhone/iPad application to keep track of vaccination

Sunday, August 14th, 2011 (last updated)

VaxTrak, brought to you by Novartis Vaccines, provides one convenient place for busy parents to keep track of vaccinations. Simply enter each family member’s info, including any vaccinations they’ve received to date. And because VaxTrak comes equipped with the Center for Disease Control schedule of recommended vaccinations, you can be confident that your loved ones are getting the protection they need because you will be updated when vaccinations are due. Use the built-in locator to find local pharmacies that give flu shots, and be ready for flu season. You can even keep track of insurance info.

Gain peace of mind as you help protect your family’s health with VaxTrak. VaxTrak contains recommendations and planning functionality to countries: UK, US Germany, France, Italy, Switzerland and Netherlands

Click here

Spread of polio in Pakistan is threatening goal of eradication

Friday, August 12th, 2011 (last updated)

With 63 cases of polio diagnosed in Pakistan this year, nearly double the number recorded in the same time period 2010, the U.N. “says that these findings suggest Pakistan could be the ‘last polio reservoir worldwide’ – the country standing in the way of eliminating only the second global epidemic disease after smallpox,” the Atlantic Wire reports.

“What’s particularly troubling now is that while the number of cases is dropping in India, Nigeria, and Afghanistan – which, along with Pakistan account for over 90 percent of cases – the disease is spreading in Pakistan (in fact Pakistani President Asif Ali Zardari has declared polio a national emergency),” the news source writes. According to a recent report, the goal of eradicating polio is threatened by a lack of funding and a reappearance of the disease in Chad, Angola, Democratic Republic of Congo and South Sudan, as well as an outbreak in the Nigerian state of Kano.

Professor Paul Offit discussing his personal experience with rotavirus disease as a young physician at a Pittsburgh hospital

Thursday, August 11th, 2011 (last updated)

Dr. Offit is not only a well-respected professional, but he is also the developer of the rotavirus vaccine generically known as rotavirus oral vaccine (commercially as RotaTeq), which has been part of the recommended childhood immunization schedule since 2006.

Dr. Paul Offit is now a pediatric infectious disease expert and Chief of the Division of Infectious Diseases at The Children’s Hospital of Philadelphia.

Rotavirus is the most common cause of severe diarrhea in children and infants worldwide. Before a vaccine was introduced in the United States, the disease caused more than 400,000 doctor visits and 200,000 emergency room visits each year, causing as many as 60 deaths annually in U.S. children younger than five. Globally, rotavirus kills more than 500,000 children each year, with most deaths in developing countries.

Fine-tuning the influenza vaccine for broader protection

Wednesday, August 10th, 2011 (last updated)

An antibody that mimics features of the influenza virus’s entry point into human cells could help researchers understand how to fine-tune the flu vaccine to protect against a broad range of virus strains. Such protection could potentially reduce the need to develop, produce, and distribute a new vaccine for each flu season.

A multi-institutional team led by Stephen C. Harrison, PhD, chief of the Division of Molecular Medicine at Children’s Hospital Boston, report their work and its implications for improving influenza vaccination this week in the Early Edition of the Proceedings of the National Academy of Sciences.

With each passing season, the two primary components of the influenza virus’s outer coat, neuraminidase and hemagglutinin (the annual flu vaccine’s primary target), mutate, allowing the virus to dodge any anti-flu immunity an individual may have generated in previous years. This evasion strategy, called antigenic drift, is why a new flu vaccine is necessary every year, a process that can take upwards of seven months.

From a public health perspective, an ideal influenza vaccine would protect against multiple strains of the virus, regardless of their hemagglutinin structure. The antibody, discovered by Harrison’s collaborators at Duke University Medical Center and called CH65, gives new insights into how the immune system’s response to hemagglutinin evolves over time, knowledge that could guide the development of just such a vaccine.

The researchers started with cells donated by an individual who received the flu vaccine for 2007. From those cells, they used genomic tools to generate a suite of antibodies, including CH65, that bound to and neutralized hemagglutinin from several seasonal flu strains. CH65 alone could bind to and neutralize hemagglutinin from 30 of the 36 strains tested.

“While it’s unusual to find such broadly effective antibodies to the flu virus, they may actually be more common than we realize,” noted Harrison, who is also an investigator with the Howard Hughes Medical Institute. “What this tells us is that the human immune system can fine-tune its response to the flu and actually produce, albeit at a low frequency, antibodies that neutralize a whole series of strains.”

CH65 mimics many key aspects of sialic acid, hemagglutinin’s natural receptor, and binds to portions of hemagglutinin that the virus cannot mutate without reducing its ability to infect human cells. After comparing CH65 with other antibodies produced from the donor’s cells, the team was able to deduce how the donor’s anti-flu immune response had evolved to produce such broadly reactive antibodies as a consequence of multiple virus exposures over time.

With this knowledge, Harrison believes it may be possible to develop vaccines that actively direct the immune response to provide broad protection against multiple strains of the influenza virus, ideally by targeting the same portions of hemagglutinin as CH65.

Fine-tuning the influenza vaccine for broader protection: the antibody CH65 gives new insights

Wednesday, August 10th, 2011 (last updated)

An antibody that mimics features of the influenza virus’s entry point into human cells could help researchers understand how to fine-tune the flu vaccine to protect against a broad range of virus strains. Such protection could potentially reduce the need to develop, produce, and distribute a new vaccine for each flu season.

A multi-institutional team led by Stephen C. Harrison, PhD, chief of the Division of Molecular Medicine at Children’s Hospital Boston, report their work and its implications for improving influenza vaccination this week in the Early Edition of the Proceedings of the National Academy of Sciences.

With each passing season, the two primary components of the influenza virus’s outer coat, neuraminidase and hemagglutinin (the annual flu vaccine’s primary target), mutate, allowing the virus to dodge any anti-flu immunity an individual may have generated in previous years. This evasion strategy, called antigenic drift, is why a new flu vaccine is necessary every year, a process that can take upwards of seven months.

From a public health perspective, an ideal influenza vaccine would protect against multiple strains of the virus, regardless of their hemagglutinin structure. The antibody, discovered by Harrison’s collaborators at Duke University Medical Center and called CH65, gives new insights into how the immune system’s response to hemagglutinin evolves over time, knowledge that could guide the development of just such a vaccine.

The researchers started with cells donated by an individual who received the flu vaccine for 2007. From those cells, they used genomic tools to generate a suite of antibodies, including CH65, that bound to and neutralized hemagglutinin from several seasonal flu strains. CH65 alone could bind to and neutralize hemagglutinin from 30 of the 36 strains tested.

“While it’s unusual to find such broadly effective antibodies to the flu virus, they may actually be more common than we realize,” noted Harrison, who is also an investigator with the Howard Hughes Medical Institute. “What this tells us is that the human immune system can fine-tune its response to the flu and actually produce, albeit at a low frequency, antibodies that neutralize a whole series of strains.”

CH65 mimics many key aspects of sialic acid, hemagglutinin’s natural receptor, and binds to portions of hemagglutinin that the virus cannot mutate without reducing its ability to infect human cells. After comparing CH65 with other antibodies produced from the donor’s cells, the team was able to deduce how the donor’s anti-flu immune response had evolved to produce such broadly reactive antibodies as a consequence of multiple virus exposures over time.

With this knowledge, Harrison believes it may be possible to develop vaccines that actively direct the immune response to provide broad protection against multiple strains of the influenza virus, ideally by targeting the same portions of hemagglutinin as CH65.

“Developing a flu vaccine is currently a hit-or-miss enterprise,” according to Harrison. “We vaccinate with a virus or part of a virus and hope that the immune response will evolve in a useful direction.

But for viruses like influenza that mutate rapidly,” he continued, “we want to have a response that does a really good job at blocking both the strain of the virus in the vaccine and many related strains as well. These results point out what strategies we might employ to achieve that goal.”

CDC update: US measles cases at highest level since 1996

Saturday, August 6th, 2011 (last updated)

Measles continues to be on the rise in the United States this year, due mostly to unvaccinated U.S. travelers to countries where measles is common. This increase underscores the ongoing risk of measles importation to the United States and the need for high measles vaccine coverage and rapid response to cases and outbreaks.

From Jan. 1 through July 1, there have been 174 confirmed cases of measles in the United States. This is the highest reported number since 1996.

Most cases (158) were associated with importations from 15 to 17 different countries, including those in Europe (including France, Italy, the United Kingdom and Spain) and Asia that have endemic measles or are experiencing large outbreaks. The imported cases involved unvaccinated U.S. residents who recently traveled abroad, unvaccinated visitors to the United States and people linked to these imported cases.

To date, 13 outbreaks (three or more linked cases) have occurred in the United States, accounting for 51% of the 174 cases. Of the total case patients, 150 (86%) were unvaccinated or had undocumented vaccination status.

On June 22, the Centers for Disease Control and Prevention (CDC) released a measles health advisory, alerting health care professionals and providing recommendations for vaccinating people before they travel internationally.

For U.S. residents who plan to travel internationally, the CDC recommends that those who are older than 6 months of age be protected against measles and receive measles-mumps-rubella (MMR) vaccine, if needed, prior to departure.

  • Infants 6 through 11 months old should receive one dose of MMR vaccine before departure. Infants who receive a dose of MMR vaccine before their first birthday should receive two more doses of MMR vaccine, the first of which should be administered when the child is 12 though 15 months old and the second dose at least 28 days later.
  • Children 12 months of age or older should have documentation of two doses of MMR vaccine (separated by at least 28 days).
  • Teenagers and adults without evidence of measles immunity should have documentation of two appropriately spaced doses of MMR vaccine. One of the following is considered evidence of measles immunity for international travelers: 1) birth before 1957, 2) documented administration of two doses of live measles virus vaccine (MMR, measles-mumps-rubella-varicella or measles vaccines, 3) laboratory (serologic) proof of immunity, or 4) documentation of physician-diagnosed measles.

Fact and fiction in tuberculosis vaccine research: 10 years later

Wednesday, August 3rd, 2011 (last updated)

Tuberculosis is one of the most deadly infectious diseases. The situation is worsening because of co-infection with HIV and increased occurrence of drug resistance. Although the BCG vaccine has been in use for 90 years, protection is insufficient; new vaccine candidates are therefore needed. 12 potential vaccines have gone into clinical trials. Ten are aimed at prevention of tuberculosis and, of these, seven are subunit vaccines either as adjuvanted or viral-vectored antigens. These vaccines would be boosters of BCG-prime vaccination. Three vaccines are recombinant BCG constructs—possible replacements for BCG. Additional vaccine candidates will enter clinical trials in the near future, including postexposure vaccines for individuals with latent infection. In the long term, vaccines that prevent or eradicate infection with Mycobacterium tuberculosis would be the best possible option. Improved knowledge of immunology, molecular microbiology, cell biology, biomics, and biotechnology has paved the way towards an effective and safe vaccine against tuberculosis. The pipeline of new vaccine candidates from preclinical to clinical testing could be accelerated by development of biomarkers that can predict the clinical outcome of tuberculosis.

Stefan Kaufmann. Lancet Infect Dis 2011; 11 (8): 633-640.

CDC is hoping to spread awareness and dispel common misconceptions regarding vaccines

Tuesday, August 2nd, 2011 (last updated)

The Centers for Disease Control and Prevention has declared August Immunization Awareness Month, hoping to spread awareness and dispel common misconceptions regarding vaccines.

“We have record or near record low levels of vaccine-preventable childhood diseases in the United States, but that does not mean these have disappeared. Many of the viruses and bacteria are still circulating in this country or are only a plane ride away. That’s why it’s important that children, especially infants and young children, receive recommended immunizations on time,” reported the CDC.

The agency is practical regarding the reservations of some patients and parents to the potential risks involved with immunizations, but insists much of the information fueling those doubts is based on falsehoods.

“Six common misconceptions about vaccination are often cited by concerned parents as reasons to question the wisdom of vaccinating their children. If providers can respond with accurate vaccination and immunization information and reassure parents on these specific issues, parents will be better able to discern inaccuracies they receive from other sources. The goal is to be sure patients and parents have accurate information with which to make an informed decision,” reported the CDC.

The first misconception often used by those against vaccination is the belief that disease had already begun to disappear before vaccines were introduced, as a result of better hygiene and sanitation.

“Improved socioeconomic conditions have undoubtedly had an indirect impact on disease…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,” reported the CDC.

According to the agency, data documenting the number of cases of a disease before and after the introduction of a vaccine demonstrate that vaccines are overwhelmingly responsible for the largest drops in disease rates. Measles cases, for example, were reported anywhere from 300,000 to 800,000 a year in the United States between 1950 and 1963, when the measles vaccine became widespread. By 1965, U.S. measles cases were dramatically dropping, with a reduction of 97-percent from the height of 800,000 in 1968.

“A similar post-vaccination drop occurred with most diseases for which vaccines are available,” reported the CDC.

“Finally, we can look at the experiences of several developed countries after they let their immunization levels drop. Three countries – Great Britain, Sweden, and Japan – cut back the use of pertussis vaccine because of fear about the vaccine. The effect was dramatic and immediate. In Great Britain, a drop in pertussis vaccination in 1974 was followed by an epidemic of more than 100,000 cases of pertussis and 36 deaths by 1978. In Japan, around the same time, a drop in vaccination rates from 70-percent to between 20-40-percent led to a jump in pertussis from 393 cases and no deaths in 1974 to 13,000 cases and 41 deaths in 1979. In Sweden, the annual incidence rate of pertussis per 100,000 children 0-6 years of age increased from 700 cases in 1981 to 3,200 in 1985. It seems clear from these experiences that not only would diseases not be disappearing without vaccines, but if we were to stop vaccinating, they would come back,” reported the agency.

The second misconception frequent among those against vaccination is that the majority of people who get diseases have been vaccinated.

“In fact it is true that in an outbreak those who have been vaccinated often outnumber those who have not – even with vaccines such as measles, which we know to be about 98-percent effective when used as recommended,” said the CDC.

The agency asserts that this is explained by two factors: no vaccine is 100-percent effective, and in a country such as the United States, people who have been vaccinated vastly outnumber those who have not.

If instead, one examines the percentage of vaccinated people that get ill in an outbreak verses the percentage of unvaccinated people; the numbers greatly favor those that were vaccinated, reported the CDC.

The third misconception concerning vaccination is what’s called “hot lots” of vaccine, which are groups of vaccine that have been associated with more adverse events and deaths than others.

The agency reported that the concept of a hot lot of a vaccine as it is used in this context is wrong. The idea is based on the presumption that the more negative reports a vaccine lot is associated with, the more dangerous the vaccine in that lot; and that by consulting a list of the number of reports per lot, a parent can identify vaccine lots to avoid.

“Vaccine lots are not the same. The sizes of vaccine lots might vary from several hundred thousand doses to several million, and some are in distribution much longer than others. Naturally a larger lot or one that is in distribution longer will be associated with more adverse events, simply by chance. Also, more coincidental deaths are associated with vaccines given in infancy than later in childhood, since the background death rates for children are highest during the first year of life. So knowing that lot A has been associated with x number of adverse events while lot B has been associated with y number would not necessarily say anything about the relative safety of the two lots, even if the vaccine did cause the events,” reported the agency.

The CDC reported that to date, no vaccine lot in the modern era has been found by the FDA to be unsafe on the basis of such reports.

The fourth common misconception concerning vaccines is fear of potential harmful side effects, illnesses, and even death.

In response, the CDC reports that vaccines are actually quite safe, with most adverse reactions as both minor and temporary, and can often be controlled by taking acetaminophen before or after vaccination.

The more serious reactions occur rarely, usually in one per thousands to one per millions of doses.

“As for vaccines causing death, again so few deaths can plausibly be attributed to vaccines that it is hard to assess the risk statistically. Of all deaths reported between 1990 and 1992, only one is believed to be even possibly associated with a vaccine. The Institute of Medicine in its 1994 report states that the risk of death from vaccines is “extraordinarily low,’” reported the agency.

“The fact is that a child is far more likely to be seriously injured by one of these diseases than by any vaccine. While any serious injury or death caused by vaccines is too many, it is also clear that the benefits of vaccination greatly outweigh the slight risk, and that many, many more injuries and deaths would occur without vaccinations,” according to the CDC.

The fifth misconception is found in the argument that vaccine-preventable diseases have been virtually eliminated from the United States, so there is no need for my child to be vaccinated.

The CDC affirms that vaccination has enabled us to reduce most vaccine-preventable diseases to very low levels in the United States. However, some of them are still quite prevalent in other parts of the world.

“Travelers can unknowingly bring these diseases into the United States, and if we were not protected by vaccinations these diseases could quickly spread throughout the population, causing epidemics here. At the same time, the relatively few cases we currently have in the U.S. could very quickly become tens or hundreds of thousands of cases without the protection we get from vaccines,” reported the agency.

The CDC stated that polio is still widespread in other parts of the world, and could easily become prevalent in unprotected individuals if it were re-introduced.

“In the early 2000s, for example, low vaccination rates in England allowed measles to become endemic once again after earlier vaccination rates had halted its continuous transmission in the country,” reported the agency.

The sixth misconception is the belief that giving a child multiple vaccinations for different diseases at the same time increases the risk of harmful side effects and can overload the immune system.

The CDC reported that several studies have been conducted to examine the effects of giving various combinations of vaccines simultaneously.

“These studies have shown that the recommended vaccines are as effective in combination as they are individually, and that such combinations carry no greater risk for adverse side effects. Consequently, both the Advisory Committee on Immunization Practices and the American Academy of Pediatrics recommend simultaneous administration of all routine childhood vaccines when appropriate,” reported the CDC.

“There are two practical factors in favor of giving a child several vaccinations during the same visit. First, we want to immunize children as early as possible to give them protection during the vulnerable early months of their lives. Second, giving several vaccinations at the same time will mean fewer office visits for vaccinations, which saves parents both time and money and may be less traumatic for the child,” reported the CDC

Dr Heidi Larson addressing the vaccine confidence gap

Monday, August 1st, 2011 (last updated)

Dr. Heidi Larson – Senior Lecturer at the London School of Hygiene and Tropical Medicine – spoke about her ongoing research into vaccine campaigns and public opinion. In this fascinating talk, Dr. Larson illuminates the current climate towards vaccines in various countries and talks about the importance of messaging.