Archive for March, 2011

Measles outbreak in Congo kills 106 children

Thursday, March 31st, 2011 (last updated)

Congolese health officials have announced that a recent outbreak of the measles has left 106 children dead.

The officials said that at least 90 of deaths were located within the Katanga province.

The medical aid group Medecins Sans Frontieres (MSF) has said that there have been approximately 21,000 measles cases centered on five provinces located in the large central African nation. The aid group has given 1.5 million vaccinations since late last year, but is looking for help to continue its effort to stop the outbreak.

Since 2008, funding cuts have contributed to the spreading of measles where it was once thought to be eradicated. The total number of cases has surged and there have been outbreaks reported in 20 African nations.

“The zone where the epidemic is prevalent is growing fast” Gaël Hankenne, the MSF head of mission in the Congo, said. “So far we can cope with the situation but the outbreak is moving north very quickly and it is going to be impossible for us to tackle.”

According to MSF, measles can kill up to 15 percent of children affected in unvaccinated populations and up to 25 percent in groups that are vulnerable, including those with limited healthcare access.

Hillarious video on vaccination

Monday, March 28th, 2011 (last updated)

Massive international effort to stop polio epidemic across West Africa

Friday, March 25th, 2011 (last updated)

Health experts today confirmed that a devastating polio epidemic in west African countries is on the verge of being stopped – but warned that complacency could breathe new life into the outbreak. Since mid-2009, polio has re-infected eleven countries across West Africa, claiming many lives and leaving hundreds of children paralyzed for life.

A series of synchronized, multi-country immunization campaigns in the second half of 2009 and 2010 have now succeeded in all but wiping out this outbreak. A further multi-country campaign on 25 March and again on 28 April across 15 countries will aim to immunize more than 38 million children, by a network of more than 180,000 volunteers armed with 48 million doses of polio vaccine, to extinguish any remaining chains of polio transmission. At the same time, polio eradication efforts are further intensifying in Nigeria, the only endemic country in Africa; over the past 12 months, the number of new cases in the country has been slashed by an impressive 95 per cent in 2010 compared to 2009.

But while the region stands on the threshold of a public health success, experts warned against complacency, cautioning that any pockets of unimmunized or under-immunized children could result in the outbreak gaining a second wind. This risk was further underscored with confirmation of a new case reported in March in Niger, across the border from northern Nigeria.

“These latest campaigns are critical to re-achieving a polio-free West Africa,” said Dr Luis Gomes Sambo, the World Health Organization Regional Director for Africa. “Under the leadership of the governments of countries across the region, this epidemic is on the verge of being stopped, but we must all invest the necessary resources to stop polio for ever in our Region.”

Even after the outbreak is stopped, periodic vaccination campaigns, along with routine immunization, will continue to ensure immunity amongst the population and to minimize the risk of another outbreak. Key to success will be the continuing engagement of political, religious and community leaders whose support has underpinned the drive to stop polio in the region.

The Global Polio Eradication Initiative (GPEI) is spearheaded by national governments, WHO, Rotary International, the US Centers for Disease Control and Prevention (CDC) and UNICEF. Since 1988 (the year the GPEI was launched), the incidence of polio has been reduced by more than 99 per cent. In 1988, more than 350,000 children were paralysed each year in more than 125 endemic countries. In 2010, 1,294 cases were reported worldwide, from 20 countries. Worldwide, only four countries remain endemic: Afghanistan, India, Nigeria and Pakistan.

The BCG World Atlas

Tuesday, March 22nd, 2011 (last updated)

Tuberculosis (TB) continues to pose a major global health threat. Someone in the world is newly infected with TB bacteria every second. Every year, more than 9 million people develop active TB and it claims about 2 million lives. In Canada, the overall incidence of TB has declined, but rates remain high among immigrants from endemic countries and among Aboriginal populations. Currently, Nunavut is facing the largest TB outbreak in the territory’s 10-year history.

In the days leading up to World TB Day 2011 on March 24, a team of researchers from McGill University and the Research Institute of the McGill University Health Centre (RI MUHC) is officially launching the BCG World Atlas: a first-of-its-kind, easy-to-use, searchable website that provides free detailed information on current and past TB vaccination policies and practices for more than 180 countries.

“The Atlas is designed to be a useful resource for clinicians, policymakers and researchers alike,” said co-author Dr. Madhukar Pai, who is an assistant professor at McGill’s Dept. of Epidemiology, Biostatistics & Occupational Health and a researcher in the Respiratory Epidemiology and Clinical Research Unit at the Montreal Chest Institute and the RI MUHC. “It has important implications on diagnosing and treating TB and on the research that’s being done on developing a new TB vaccine.”

Ms. Alice Zwerling, BCG Atlas project leader and PhD candidate in epidemiology at McGill, explained that BCG vaccination can cause false positives in the skin test that’s routinely used to screen for latent TB. “As a clinician, if you’re trying to interpret the skin test in a foreign-born person, you’re going to want to know when the BCG vaccination was given back home and how many times it has been given. The Atlas provides this information and can help doctors decide on when to use the newly available blood tests for TB that are not affected by BCG vaccination,” she added.

BCG World Atlas is available at: http://www.bcgatlas.org/

Scientists Find Candidate For New TB Vaccine

Saturday, March 19th, 2011 (last updated)

Scientists have discovered a protein secreted by tuberculosis (TB) bacteria that could be a promising new vaccine candidate, they report today in Proceedings of the National Academy of Sciences. The protein could also be used to improve diagnosis of TB.

TB is caused by the bacterium Mycobacterium tuberculosis (MTB), which infects the lungs and spreads through the air as a result of coughing. There are 9 million new cases of TB each year, killing 4,700 people a day worldwide.

BCG is the only available vaccine but it is of limited effectiveness in protecting against TB. BCG derives from the Mycobacterium bovis bacterium, which infects cattle and is closely related to MTB.

In the new study, scientists identified a protein, called EspC, that triggers a stronger immune response in people infected with the TB bacterium than any other known molecule. This protein is secreted by the TB bacterium but not by the BCG vaccine. As a result, the BCG vaccine does not induce an immune response to this protein, so deploying it as a new TB vaccine would provide additive immunity over and above that provided by BCG.

“Despite most of the world’s population having had a BCG vaccination, there are still 9 million new cases of TB every year,” said senior author Professor Ajit Lalvani, from the National Heart and Lung Institute at Imperial College London. “So we urgently need to develop a more effective vaccine for TB.

“We’ve shown that EspC, which is secreted by the bacterium, provokes a very strong immune response, and is also highly specific to MTB. This makes it an extremely promising candidate for a new TB vaccine that could stimulate broader and stronger immunity than BCG. Surprisingly, our results also show that this molecule could underpin next-generation diagnostic blood tests that can rapidly detect latent TB infection.”

Research May Lead To New And Improved Vaccines

Tuesday, March 15th, 2011 (last updated)

Alum is an adjuvant (immune booster) used in many common vaccines, and Canadian researchers have now discovered how it works. The research by scientists from the University of Calgary’s Faculty of Medicine is published in the March 13 online edition of Nature Medicine. The new findings will help the medical community produce more effective vaccines and may open the doors for creating new vaccines for diseases such as HIV or tuberculosis.

“Understanding alum properties will help other vaccines because we are one step deeper into the mechanistic insight of adjuvants, which are essential for human vaccines to work,” says Yan Shi, PhD, from the Faculty of Medicine and a member of the Snyder Institute of Infection, Immunity and Inflammation.

Alum is very effective in inducing antibody responses. It has been in use for 90 years.

“Knowledge provided in this study may help us manipulate alum with additional adjuvant components to direct an attack against major diseases which require a killer T cell response such as HIV, Tuberculosis, and malaria,” says Tracy Flach from the Faculty of Medicine and the study’s first author.

The research reveals that alum interacts with a group of immune cells called dendritic cells via their cell membrane lipids. Dendritic cells, the sentinel of our immune system, heed the call of alum and move on to activate a group of T cells that control antibody production.

The breakthrough came as the team made use of a cutting edge technology developed in the Faculty of Medicine called single cell force spectroscopy. This technique allowed the UCalgary team to study individual cells and measure their responses to alum.

Investigators find no impropriety in WHO’s handling of H1N1 pandemic

Friday, March 11th, 2011 (last updated)

Independent experts investigating the World Health Organization’s management of the response to the H1N1 pandemic recently announced that they found no evidence that the drug industry influenced the agency’s decision making over how to handle the virus.

In a draft report, the panel did acknowledge that the WHO failed to understand and respond to conflicts of interest among experts on its advisory Emergency Committee, which had previously acknowledged their pharmaceutical industry ties, according to Reuters.

The experts concluded that the body remains ill-prepared to face a similar public health crisis brought on by a significant influenza pandemic.

In June 2009, the WHO declared that the world was facing its first influenza pandemic in 40 years, caused by the H1N1 virus. In August 2010, it declared the pandemic over, stating that the global outbreak was less severe than was first believed.

Critics suggested that WHO was unduly influenced by the interests of pharmaceutical companies that stood to gain financially from the preparations involved in fighting a global outbreak, Reuters reports.

According to the panel, headed by American flu expert Dr. Harvey Fineberg, the critics have ignored the agency’s core mission to prevent disease and save lives.

“WHO performed well in many ways during the pandemic and confronted systemic difficulties and demonstrated some shortcomings,” the panel said in a 33 page report, according to Reuters. “The committee found no evidence of malfeasance.

“As far as the Review Committee can determine, no critic of WHO has produced any direct evidence of commercial influence on decision-making.” The review committee, comprised of 27 experts, will convene its last meeting at the end of March and submit its report to the WHO’s annual ministerial meeting in May.

The WHO did not escape criticism for its handling of events. The panel pointed out the agency’s inconsistent and immeasurable system for judging a pandemic’s severity, which it says led to increased confusion. In response, the panel suggested a scale of three phases to measure the severity of a pandemic, as opposed to the current six phase system. The panel also criticized the WHO bureaucracy for preventing the timely distribution of donated vaccines to poorer countries. “The world is ill-prepared to respond to a severe influenza pandemic or to any similarly global, sustained and threatening public health emergency,” the panel concluded, Reuters reports.

Vaccine researchers warn of return of 1957 flu

Friday, March 11th, 2011 (last updated)

Three vaccine researchers from the National Institutes of Health say that influenza A/H2N2 viruses, which caused the flu pandemic in 1957 and 1958, might return and lead to a pandemic similar to the H1N1 epidemic in 2009.

In a commentary published in this week’s issue of Nature, the scientists assert that the threat is large enough to warrant creating a preemptive vaccination strategy, CIDRAP News reports. Since the H2N2 viruses have circulated in pigs and birds but not humans for 50 years, the scientists worry about lack of immunity to the subtype.

They reference the 1918 H1N1 virus that had a similar hemagglutinin component in pigs for over a century, which was “poised to cross back into humans and cause a new pandemic when broad protective human immunity had waned,” the article said.

The H2N2 virus continued to circulate after 1958 until it was displaced by the H3N2 virus in 1968, which has circulated ever since. H2N2 strains have not been found in humans for many years.

The authors conducted their study between 2003 and 2007, testing 90 people for immunity to H2N2. “Our study suggests that people under 50 have little or no immunity, and resistance dramatically increases for those over 50,” the authors wrote. “The low mutation rate for H2N2, and evidence of waning human immunity, make it likely that an H2N2 pandemic could arise from animals.”

Author spotlights vaccine safety

Thursday, March 10th, 2011 (last updated)

Infectious disease expert Paul Offit (Children’s Hospital in Philadelphia) wrote a very interesting book: “Deadly Choices: How the Anti-Vaccine Movement Threatens Us All”.

A man took his infant son in for a vaccination. That night, the child died of Sudden Infant Death Syndrome. Could the shot have caused his son’s death? In this case, it did not. When the man got to the doctor’s office, the line was too long. He took his son home without getting vaccinated, intending to return the next day. But suppose he had waited? Forever after he would have wondered if maybe — just maybe — that shot had been responsible.

“Deadly Choices: How the Anti-Vaccine Movement Threatens Us All,” by Paul A. Offit, uses this story to illustrate the difficulties of assigning responsibility for problems caused by, or assumed to have been caused by, vaccines. He shows how those uncertainties have been exploited by those opposing vaccination to fan fear.

Paul Offit shows how the modern anti-vaccine movement started after a British study suggested a link between the whooping cough vaccine and brain damage in infants. The results of the study could not be repeated in other studies and eventually were repudiated.

Their anti-vaccine arguments, Paul Offit says, consist of nothing more than anecdotal drama combined with conspiracy theories that pander to parents’ most emotional fears. What they should be doing, he says, is encouraging parents to trust the huge bank of scientific data proving the safety of vaccines and their efficacy in eliminating many deadly infectious diseases.

“Deadly Choices” is a book that should be read by any parent worried about vaccine safety.

No direct link between vaccines and death of children in Japan

Tuesday, March 8th, 2011 (last updated)

A panel of experts at Japan’s health ministry found no direct link between vaccines made by Pfizer Inc and Sanofi-Aventis and the deaths of children, but said further checks were needed.

The ministry halted the use of Pfizer’s Prevenar and Sanofi’s ActHIB vaccines in response to the deaths of four children shortly after receiving the vaccines.

U.S. health officials have said they were aware of the deaths in Japan but have not seen any such safety concerns in the United States.

Three of the children that died in Japan were administered Prevenar together with ActHIB. In addition, three of the children also received a mixed vaccine against diphtheria, whooping cough and tetanus on the same day they received the other vaccines.

Three of the four children died a day after being immunized. The deaths happened between March 2 and March 4.

Representatives for Pfizer and Sanofi in Tokyo have said the companies were cooperating with the investigation.