vaccine

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Visualizing a vaccine breaking new ground, and chains, in Africa | 

Guest post by Katie Leach-Kemon, a policy translation specialist from the University of Washington’s Institute for Health Metrics and Evaluation.

A child in Burkina Faso receives a vaccination against meningitis.
A child in Burkina Faso receives a vaccination against meningitis.
WHO, PATH

One of the biggest obstacles to expanding immunization to the remotest regions on the planet has been that vaccines must be kept refrigerated at low temperatures.

Keeping vaccines cool during their entire trek – from the manufacturer to a ship or airplane to a refrigerated truck down to the guy riding a bicycle with a cooler – is known as the ‘cold chain.’

A new vaccine created by Seattle-based PATH, with help from the World Health Organization and other partners, now indicates it may be possible to break free from these chains.

The vaccine, known as MenAfriVac, was designed specifically for the ‘meningitis belt’ of central Africa – a region that had seen tens of thousands of annual deaths from this disease, not to mention the survivors left brain damaged, deaf or otherwise disabled.

map-meningitis-belt-engSince the new vaccine campaign began, more than 150 million people have been vaccinated and disease rates have fallen significantly. Africa’s so-called ‘meningitis belt’ may soon disappear.

In addition, a new study of the vaccine’s use in the field is being hailed by some as evidence the cold chain may also soon go the way of horse-and-buggy. Continue reading

Gates-backed test malaria vaccine is celebrated, half glass full | 

African child with cerebral malaria
African child with cerebral malaria
Mike Urban

An experimental malaria vaccine, made by GSK with backing and support on the research side from the Bill & Melinda Gates Foundation and Seattle-based PATH, has (again) been shown to protect half the children in the study were immunized against malaria.

The results, announced today in Durban, South Africa, are pretty much the same as earlier findings that continue to emerge from a long, ongoing study of GlaxoSmithKline’s RTS,S vaccine.

The scientific gist of the latest findings, as was reported back in 2008, is that the vaccine appears to protect about half the kids from getting sick, its ability to protect drops significantly following vaccination, it requires repeat doses and GSK estimates it will cost a few dollars at least.

Is that a glass half full or half empty? Continue reading

From smallpox victim to polio eradication advocate | 

Ali Maow Maalin
Ali Maow Maalin
WHO

Ali Maow Maalin of Somalia died suddenly at the age of 59 last week. He was the last person infected with smallpox in the world.

What he did with his life after the infection is what makes Maalin’s story truly remarkable. He took his experience and set his sights on eradicating polio.

Maalin refused the smallpox vaccine when he was younger because he feared needles. Refusing the vaccine is why he contracted smallpox while driving to a clinic with an infected family. He explained to the Boston Globe’s John Donnelly in 2006:

”I was scared of being vaccinated then. It looked like the shot hurt,” said Mo’allim, 48, who was sick for 50 days with smallpox but recovered completely. ”Now when I meet parents who refuse to give their children the polio vaccine, I tell them my story. I tell them how important these vaccines are. I tell them not to do something foolish like me.”

“He would always say, ‘I’m the last smallpox case in the world. I want to help ensure my country will not be last in stopping polio,’ ” Dr. Debesay Mulugeta, who leads polio eradication efforts in Somalia, said the the NPR Shots Blog.
Continue reading

Financial investors buy $700 million in bonds for global vaccines | 

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Gates Foundation

Public health emergencies arise around the world on a regular basis.

Humanitarian and aid organizations need to act quickly, but they need money to get work done. An emergency appeal for millions, if not billions, of dollars can take time to fulfil.

So what if the money was already available? With the money in place, an organization can respond to an emergency immediately.

The International Finance Facility for Immunisation Company (IFFIm) does just that for the GAVI Alliance, a public-private global health organization that increases access to immunizations in poor countries by working with governments, donors and the private sector.

IFFIm sells bonds to private investors in order to raise money for GAVI’s vaccine work. When GAVI needs money a request is made to IFFIm’s board to disburse the needed funds. For vaccines, a health solution that requires early action, gaining access to needed funding quickly has a big impact on programs like the eradication of polio.

“Having predictable, long-term funding in place will help us ensure that the world’s most vulnerable children have access to healthcare, and that is a critical step in achieving the goal of ending extreme poverty by 2030,” said Jim Yong Kim, President of the World Bank.

Continue reading

Vaccinophobia: World’s most powerful disease preventing tool, the vaccine, still a hard sell | 

A shot at life

UNICEF

A shot at life

The benefit of expanding the use of vaccines worldwide seems like a no-brainer: A cheap and easy way to stop disease dead in its tracks.

Yet polio persists despite a massive global campaign. The crippling disease is back in the Horn of Africa and new violence against vaccinators in Pakistan prompted the World Health Organization to again suspend its polio immunization work there.

The ups and downs of the polio campaign is a cause for concern to those seeking to eradicate this disease. But it isn’t just polio vaccines, or vaccinators, in poor countries that are targeted. There’s a disturbing synchronicity among vaccine opponents – whether it’s the Pakistani Taliban, Nigerian Islamists or Seattle granola heads. Seattle, in addition to being an epicenter for global health, is also known for having the lowest rate of child vaccination for any US city.

Part of the problem may be that a vaccine’s benefit is invisible on the individual level – lack of death and disease. Perhaps another reason vaccines are so frequently targeted for boycotts is the contagion of scientific illiteracy. Continue reading

TB vaccine study dissapoints | 

tuberculosis patient, El Salvador
tuberculosis patient, El Salvador

As a Reuters article from last week indicated, there were high hopes the results from a study of an experimental TB vaccine would show promise.

“In my own personal view, I will consider this (trial) to be a landmark or a watershed,” said Peggy Johnston, senior program officer at the Bill & Melinda Gates Foundation in Seattle. “If it is negative, it would be the first trial we can demonstrate that yes, we can conduct a clinical trial and get a solid answer. If it turns out to be at all positive, it will be a clear watershed for the field.”

Unfortunately, the study did not yield a positive result, at least in the latter sense.  TB, though seldom in the news like HIV or malaria (or the threat of pandemic flu), remains one of the world’s biggest killers and the bacteria is becoming increasingly drug -resistant. As a number of news articles reported on this latest attempt to find a better vaccine:

BBC and the Guardian both reported ‘Hopes for new TB vaccine dashed

NPR sounded a more hopeful note, saying that though this vaccine failed to protect infants there are lots of other candidate vaccines under study.

Seattle AIDS vaccine scientists celebrate new clues – and uncertainty | 

Jim Kublin provides an overview of AIDS vaccine science at Seattle HVTN meeting

Seattle is home to the world’s largest HIV vaccine research network and, as a scientitic meeting here this week indicated, they’re quite comfortable with not knowing where they’re heading.

“We actually don’t know what the agenda is,” said Dr. Jim Kublin, executive director of the HIV Vaccine Trials Network (HVTN) based at Seattle’s Fred Hutchinson Cancer Research Center.

That drew a lot of laughs from the audience, since Kublin’s lecture title for the day was ‘Scientific Agenda, the Next Seven Years.’

“That’s the way science is,” Kublin told me after his talk. “Good science is based on uncertainty, on having an open mind and dealing with the unknown.”

But what makes it easier to laugh about not knowing where you’re going, he added, is that researchers today have a lot more tantalizing clues – beginning with the ground-breaking Thai vaccine trial known to this bunch as RV 144. Continue reading

ArsTechnica: The difficult search for a malaria vaccine | 

Seattle writer Robert Fortner, in ArsTechnica, examines how far we have come in the search for an effective malaria vaccine.

This story is focused on what many consider the most promising malaria vaccine candidate, called RTS,S, made by GlaxoSmithKline decades ago and being tested (again) under improved formulations with funding from the Bill & Melinda Gates Foundation and the PATH Malaria Vaccine Initiative. As I’ve noted before, many experts are quietly expressing doubt RTS,S will work even though it has provided some new insights into the immunology of malaria.

Bob digs deeper into the evidence:

Photo by Caitlin Kleiboer

Testing the RTS/S malaria vaccine in Malawi

After clean water, vaccines may have saved more lives than any other public health intervention. Eradication of malaria, a disease that may have killed more humans than any other single cause, likely requires a malaria vaccine.

However, after nearly a century of research, today’s only candidate might not pack enough immunological punch to win deployment. Sadly, there are no obvious successors. Goals for vaccines set in 2006 are now approaching, but may not be possible to meet.

A quarter century of painstaking work has gone into the vaccine known as RTS,S, now in phase III clinical trials. But after numerous modifications and enhancements, RTS,S still protects only intermittently, 30 to 60 percent of the time.

This protection wanes, although over how many years or months is still being studied. The vaccine reduces disease but, so far, not deaths.

The organism that causes malaria has made vaccine development a challenge. Malaria is caused by the parasite Plasmodium rather than bad or “mal” air as thought long ago. The human genome, particularly in sub-Saharan Africa, chronicles our lengthy and ongoing battle with Plasmodium.

Strong selection pressure on humans has led to evolutionary gambits like the sickle cell trait—risking potentially lethal blood disorders to reduce susceptibility to malaria infection. But Plasmodium has kept the upper hand in many ways. The parasite continues to baffle the immune system with a complex genome reshuffled by sexual reproduction, a multi-stage life cycle that features antigenic shape-shifting, to avoid immune surveillance.

For pathogens like polio, the human immune system can develop durable, sterilizing immunity, which rids the body of the invader. Polio vaccines reliably trigger these natural mechanisms. For malaria, humans can acquire a kind of immunity and potentially even clear parasites completely. But the genetic diversity of Plasmodium falciparum allows it to often avoid such direct hits.

Acquired immunity is often a détente in which the parasite survives and reproduces at low levels that cause neither disease nor death. A study in western Kenya, for example, found 90 percent of a cohort was infected with falciparum even though not one of the 93 people was ill. Vaccines like RTS,S prod the immune system toward this partial protection, but there is concern that it isn’t reducing severe malaria enough.

Continue reading at ArsTechnica.