vaccine

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April 25, 2012 | 12:10 PM | By

Infectious hope: When getting malaria makes sense

Flickr, Aya Rosen

It’s World Malaria Day. There’s been great progress against malaria over the past decade but most experts agree the best hope is to find an effective vaccine. Seattle Biomed is one of the world leaders in malaria vaccine research, but testing these experimental vaccines relies on people volunteering to get the vaccine — and get bitten. What it’s like to get infected for science.

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By Cyan James, special correspondent

Cyan James

Lane Rasberry wants to better arm the world against malaria

“I’m going to get infected and I’m going to love it,” Lane Rasberry says with a smile.

Rasberry is about to spend at least five minutes with more than a dozen mosquitoes full of malaria parasites.

The mosquitoes huddle in a screened, pint-sized container, waiting for Rasberry to roll up his left sleeve, lay his forearm over the container, and drape a towel over his arm to simulate night. Then they launch, feeding on Lane until their breakfast clock runs out.

A Wikipedia editor by day, Rasberry also volunteers in a malaria vaccine trial at Seattle BioMed, where he belongs among a unique group of clinical subjects who intentionally get infected.

Why? For Rasberry, it’s because the research is both altruistic and convenient, and because it plays to his interest in science. “I actually enjoy participating,” he says, emphasizing research trials’ ability to create community and help others learn about scientific advances. Plus, since he grew up in Texas, the mosquitoes don’t really faze him.

Seattle Biomed, Earl Harper

Mosquito dissection

After Rasberry’s five minutes are up, a technician dumps his mosquitoes into an ethanol bath to kill them, then flicks off the mosquitoes’ heads, presses their torsos to extrude their innards, and swiftly isolates their salivary glands.

Cyan James

Skeeter dissection

The technician scans the tiny sickle-shaped glands under a microscope, searching for P. falciparum, the parasite that infects up to 500 million people with malaria every year and kills nearly two people every hour.

Continue reading →

FILED UNDER: Health, Science, Cyan James, malaria, Malcolm Gardner, Sara Healy, Seattle Biomed, Stefan Kappe, vaccine
February 27, 2012 | 9:47 AM | By

Seattle scientists to test world’s first vaccine against ‘black fever’ – leishmaniasis

WHO

Boy with kala azar, viscerial leishmaniasis

There are many neglected diseases out there but not many as prevalent or as ravaging as visceral leishmaniasis, also known as black fever or kala azar — the ‘parasitic version of AIDS.’

Scientists at Seattle’s Infectious Disease Research Institute will soon begin testing an experimental vaccine they have designed to work against the most deadly form of this common parasitic disease spread by the bite of sand flies.

Leishmaniasis, in both its cutaneous (surface of the skin) and visceral (internal organ) forms, infects an estimated half million people every year on every continent except Australia and Antarctica. It is the second most common parasitic disease after malaria, but has until recently gotten little attention as a major global health problem.

Because the parasite attacks blood cells, immune system cells and also invades organs and bone marrow much like HIV, visceral leishmaniasis is sometimes called ‘parasitic AIDS.’

“Visceral leishmaniasis is a persistent and deadly global health problem,” said Steve Reed, IDRI founder and Chief Scientific Officer, who led the over twenty years of preclinical vaccine work. “Our partnership with India will speed the development of an effective vaccine and accelerate its control.”

The vaccine against visceral leishmaniasis (VL) that IDRI has created will be tested first for safety on 36 volunteers in Seattle and then the Phase I study will be expanded to sites in India, which suffers from a disproportionately high caseload of the disease.

The non-profit Seattle-based research organization has been working on leishmaniasis for decades but received a major boost in 2006 when the Bill & Melinda Gates Foundation awarded IDRI $32 million to find a vaccine against VL, kala azar.

As part of the grant, the Gates Foundation requires research organizations also develop a plan to make vaccines or drugs affordable in poor countries.

To reduce costs of the new vaccine, should it prove effective, IDRI is transferring its vaccine technology to an Indian drug firm, Gennova Biopharmaceuticals. Gennova has already opened a vaccine development center in Pune, India, where the company is based.

“With this clinical trial, we hope to launch a new era in the fight against Visceral Leishmaniasis,” said Franco Piazza, Medical Director at IDRI and leader of the vaccine’s clinical development. “For the first time, an advanced vaccine to prevent this devastating disease is being tested in people.”

U.S. Armed Forces Pest Management

A sand fly bite

While leishmaniasis is treatable today, the treatments are fairly toxic, cumbersome and often too expensive to use in poor communities. Some 500,000 people get infected every year, with an estimate 50,000 deaths per year, and the disease appears to be spreading.

Just as with mosquitoes, sand flies that carry the parasite appear to be expanding their range worldwide due to climate change, migration and other global changes.

FILED UNDER: Science, Infectious Disease Research Institute, leishmaniasis, Steve Reed, vaccine
November 3, 2011 | 11:22 AM | By

Lacking a dengue vaccine, scientists tinker with skeeter genes

It’s rarely on most Americans’ minds, but worldwide dengue is a big killer. And it’s spreading fast.

The U.S. Centers for Disease Control and Prevention says there are anywhere from 50 to 100 million people infected every year with dengue — including a very small, but increasing number of Americans — and an estimated 50,000 deaths from this mosquito-born disease.

Here’s an interactive look (go to this link) at dengue around the world from HealthMap:

HealthMap, CDC

The number of cases of dengue have exploded over the past few decades in tropical and semi-tropical regions. Some believe this may be driven by climate change and an expanded range for the mosquito (Aedes aegypti, which also carries yellow fever).

WHO

Dengue cases over time

Others think shipping, cargo transportation, may be the main route of spread. This skeeter tends to like to live in urban and semi-urban areas.

Because of the global surge in dengue, the U.S. military and some pharmaceutical companies have stepped up efforts to develop a vaccine that can protect against the infection. The Bill & Melinda Gates Foundation has donated $60 million to the vaccine efforts as well as some more ‘innovative’ approaches such as modiying the genes of mosquitoes.

Earlier this week, a team of scientists (partly funded by Gates) reported success in a field trial of mosquitoes genetically modified so that their offspring die following reproduction. As the BBC noted, dengue can’t be fought with same tools as malaria, such as bed nets, primarily because these mosquitoes bite during the day time.

The successful field trial — which just tested the genetic tinkering’s effect on reproduction, not dengue transmission — has nevertheless raised concerns about unintended environmental side-effects, the New York Times reports. 

The British biotech company pursuing this approach, Oxitec, had already raised some hackles earlier for too aggressively moving forward with their releasing modified mosquitoes into the wild.

Meanwhile, to much less media attention and fanfare, other scientists (many of them also funded by the Gates Foundation) are working on developing a vaccine against dengue. Here is one recent news brief about an ongoing trial.

For a broader overview of work on developing a vaccine, see the Dengue Vaccine Initiative.

FILED UNDER: Science, dengue, genetically modified organisms, vaccine
October 28, 2011 | 12:08 PM | By

Experts question Gates-Glaxo malaria vaccine report

Flickr, Aya Rosen

Many of the world’s leading vaccine experts and the prestigious British journal Nature are raising questions about the potential efficacy of an experimental malaria vaccine — and the way it is being promoted by scientists supported by the Gates Foundation.

As Nature News’ Declan Butler reports in Malaria vaccine results raise scrutiny:

To judge from last week’s headlines, scientists had made a big breakthrough in the long campaign to create a malaria vaccine ….

Yet several leading vaccine researchers, who are critical of the unusual decision to publish partial trial data, argue that the results raise questions about whether the RTS,S candidate vaccine can actually win approval.

Continue reading →

FILED UNDER: Health, Science, Bill & Melinda Gates Foundation, GlaxoSmithKline, malaria, PATH, vaccine
October 25, 2011 | 12:03 PM | By

Three reasons not to get too excited about the Gates-Glaxo malaria vaccine

Last week, the biggest news out of the Gates Foundation’s Malaria Forum were some interim results of an ongoing test of an experimental malaria vaccine.

Many, if not most, media reported the findings in somewhat hyperbolic fashion as a “major milestone,” a “breakthrough” or “world’s first malaria vaccine.”

Google News on the malaria vaccine

Despite the hype and fanfare, many experts at the Seattle meeting said this experimental vaccine (known as RTS,S) actually so far represents only incremental progress — a scientific achievement which may still turn out to have little practical utility in the real world. They usually only said so privately, given that the Gates Foundation preferred to hear “optimistic” assessments rather than cranky ones.

1. No breakthrough. Let’s first put to bed the claims that these findings represent a major milestone. In fact, the findings largely repeat earlier ‘interim’ results that have continued to find the vaccine protects only half of those immunized — and appears to wane fairly rapidly over time.

So that’s the first reason — a point also made in this (terribly titled) Huffington Post article A vaccine that works only half the time is not the shot in the arm malaria needs. The author, Tido von Schoen-Angerer, director of Médecins Sans Frontières‘ essential medicines campaign says:

But while the latest advance toward the development is scientifically important, there are several reasons to be cautious about the difference this vaccine could make, on the basis of current results.

2. The cost question. The second reason this halfway effective malaria vaccine may not work is cost. The manufacturer GlaxoSmithKline has refused to say what it thinks it will have to charge for the vaccine, other than to say it would be “at cost” plus 5 percent. Neither the PATH Malaria Vaccine Initiative, which is working with GSK on the malaria vaccine trial, or the Gates Foundation (which funds the PATH initiative) will say what price they think is feasible. Many say anything over a dollar might be too much for poor countries.

3. The science. It is promising that researchers have shown a vaccine against malaria is possible. But there’s a lot of other research out there indicating why it may be quite difficult to get a malaria vaccine that can perform as well as most of us expect a vaccine to perform — providing ideally something like 90 percent protection but hopefully not lower than 70 percent. Continue reading →

FILED UNDER: Health, Science, Bill & Melinda Gates Foundation, GlaxoSmithKline, malaria, Medicins Sans Frontieres, PATH, vaccine
February 14, 2011 | 9:05 AM | By

Fighting pneumonia, world’s biggest killer of children

There are a number of news stories out there now marking the big roll-out this week of a new vaccine against pneumonia. Here’s one story out of Kenya, and another which notes this is just the beginning of a global effort.

Sarah Boseley at The Guardian takes note, and also asks if it could have been done at less cost.

For a good overview of what this is all about, and why it is so significant, read this column by Johns Hopkins pneumonia expert Dr. Orin Levine at Huffington Post.

Here’s a nice informational video from GAVI profiling the roll-out in Nicaragua:

Fighting Pneumonia

FILED UNDER: Health, GAVI, Orin Levine, pneumonia, vaccine
December 6, 2010 | 8:00 AM | By

PATH, WHO and others launch a “revolution” to end Africa’s meningitis epidemics

CDC

Meningitis Belt

Today could be the beginning of the end of a deadly and disabling epidemic of bacterial disease that, for reasons not fully understood, occasionally burns an exceptionally tragic swath across central sub-Saharan Africa from Senegal to Ethiopia.

The “meningitis belt.”

Starting today, PATH, the World Health Organization and a host of other partners begin fanning out across Burkina Faso, then to Mali and Niger to launch a massive vaccination campaign initially targeting 20 million people with the broader aim — if it gets fully funded — of ending these epidemics in 22 more countries and erasing this stripe of death and destruction.

“When these major meningitis outbreaks occur in these communities, it’s terrifying and everyone just stays inside … they just shut down,” said Dr. Marc LaForce, director of the Meningitis Vaccine Project.

Meningitis can be caused by any number of things. The term simply means an inflammation of the brain and spinal cord, an inflammation that can kill, cause brain damage, deafen or otherwise disable. In Africa’s meningitis belt, LaForce explained, the cause is a particular bacteria known as meningococcal A.

Meningitis can occur anywhere, but not like in the meningitis belt, LaForce said. Continue reading →

FILED UNDER: Health, Burkina Faso, meningitis, PATH, vaccine, World Health Organization