Sunday, December 11, 2011

HIV Vaccine potential-sketchy or promising?

Duke University is working on developing HIV vaccines. The idea behind the vaccine is that it owuld bind to hte GP-120 glycoportein on HIV's envelope.

The paper refers to a previous trial in which Thailand developed a vaccine that was "partially effective"

I think this article is interesting in that it mentions the specific receptor that vaccine is expected to bind to. But it doesn't elaborate on the mechanism of action after binding and how it work. Also, the "partially effective" vaccine form Thailand sounds kind of sketchy - I'm curious to learn how it was partially effective and how the researchers tested it.
Overall, this article proposes a good idea, hopefully there will be a HIV vaccine in the future.

-Michelle Jin

Monday, December 5, 2011

China to manufacture vaccines for global market

After meeting WHO international standards for vaccine regulation in March, China is now poised to make a splash in the global vaccine scene. Groups like GAVI (which purchases enough vaccines to cover 50 million children annually) are particularly excited about this move, which will result in more favorable prices. China currently produces almost 1 billion doses of vaccines a year.

However, you can't discuss Chinese vaccines without being reminded of their current track record - 2007 saw 93 deaths due to Chinese cough syrup, for example. In 2008, hundreds of thousands of infants were poisoned by powdered milk tainted with melamine; shockingly, even more powdered milk was found to be contaminated in 2009. Suffice to say that scandals like these do not inspire confidence in the ability of Chinese manufacturers to produce safe products in massive quantities.

With that in mind, we can anticipate the need for a regulatory body to ensure that these vaccines continue to be produced to international standards. However, one Chinese health expert, Yanzhong Huang, says that such an agency wouldn't be enough - what China needs is "the market economy, democracy, media monitoring, civil society, as well as a well-developed business ethics code." In short, China needs to change the way it does business before people in the international market will feel comfortable using their vaccines. (This could lead to a whole separate discussion on Chinese society and economy, but that's really beyond the scope of our class, so I'll just change tack here.)

Chinese-produced vaccines will likely be tough to deliver to the American public, if current exemption rates from childhood vaccines are any indication. Relevant comment is relevant:

"If they started producing all vaccines in china and phased out the American made ones I would refuse every last chinese vaccine. If my kid has to go unvaccinated because i dont wanna risk her being killed by a tainted chinese pharmaceutical then so be it. I know if they allow the chinese to produce vaccines the population of unvaccinated children will spike and spiral out of control. This decision will singlehandedly lead to the return of polio and other diseases like smallpox."

Sounds like closed-mindedness with a dash fearmongering, right? Sure, but that doesn't change the possibility that some sub-par Chinese vaccine product will slip through the cracks, especially at the volume at which they'll be produced.

We're going to need some intense regulation of these vaccines, but the manufacturing capacity provided by China's facilities will be a boon to immunization and eradication efforts worldwide.

-Alan Le

P.S. Pardon the lateness! Looking forward to seeing everyone's models :]

Washington Times: China positions itself to become major player as vaccine provider

Monterey County Herald: China to enter vaccine market

Sunday, December 4, 2011

Breakthrough discovery on mechanism of prion disease

Researchers from the University of Alberta doing studies on prion disease have discovered a new property of prion diseases that changes the way we think about prion diseases. While studying BSE, the researchers found that prion particles as well as bystander proteins were being destroyed in the brains of infected individuals for up to 7 months before the animal started showing symptoms. This means that the brain "fights back" more than was previously thought. Additionally, the study shows that prion diseases can change depending on the brains reaction, and might not be irreversible. If we can learn from how the brain fights off the infection for those months before symptoms appear, we may be able to gain insight into possible treatments for prion diseases.

--Sarah Kaewert

HIV+ Philadelphia teen denied entry to school

Someone's already written this up (whoops) but speaking of both "dual-use" science controversies and flu...I read about the controversy over the engineered H5N1 that's super infectious! It's interesting that they proposed the type of censorship that I was thinking about in the last problem set (i.e. publish generally, to get specifics you need clearance)—but just who would get access to the classified information? I tend to think of bioterrorists like I think of suicide bombers (using crappy kitchen tech), but the truth is that some legit scientists could definitely turn bioterrorist (i.e., the guy sending anthrax, a top researcher for the government who apparently was a co-creator of the vaccine). My brother recently told me about the plot line of a novel series/videogame called "Rainbow 6" in which the bioterrorists work for a biotech firm, and plan to throw virus into the fans at the Sydney Olympics in order to kill everyone off (except themselves, who are of course vaccinated) and thus save the ecological world from destruction. It's scary how "bioterrorists" could come from within our own institutions.


A 13 year old boy was denied admission to a private boarding school in Philadelphia because "it was necessary to protect the health and safety of the 1,850 enrolled in the institution." The AIDS Law Project is, of course, suing the school for discrimination, interestingly enough under the "Americans with Disabilities Act." I guess there's not really a medical-condition-specific discrimination law? A 6-year-old in Jakarta, Indonesia was also thrown out of school because her father is HIV+; she may be able to get in if she proves she is not HIV+.

It's interesting that there's still so much prejudice over HIV, even in America. (I mean, what's the likelihood that this 13 year old would spread it to his classmates? How much unprotected sex/needle drug usage is there in that school?) Even more for a 6-year-old whose father has it. I thought ostracization happened in Africa, or decades ago in America. For shame.



WHO Weighs in on European Measles Outbreak

The WHO, through an issue of their publication the Weekly Epidemiological Record, has announced that 26,000 cases of measles have occurred throughout Europe from January 2011 to October 2011. This figure is a steep rise from any previous and indicates the possibility of a continued outbreak of the deadly disease. They have placed blame mainly on fallout from the autism-vaccine controversy created by Andrew Wakefield and failure by European governments to properly enforce vaccinations as over 90% of cases where in unvaccinated people or people of unknown status. European governments have already begun responding to the outbreak, with France launching a high-profile campaign to drive up vaccination rates in reaction to 6 deaths and 14,000 cases experienced there.
These cases present a rather large set-back for the established goal of eliminating measles in Europe by 2015 and for world-wide eradication. Indeed, the European outbreak has also been tied to international outbreaks as a result of infected travelers to foreign countries. This just goes to show that the existence of a highly effective vaccine and even strong political will does not guarantee effective control of a disease.

-Zachary Herrera


US Reflection on HIV/AIDS Awareness

According to the Centers for Disease Control, only one quarter of Americans with an HIV infection have the infection under control. By "under control," they means that they have a suppressed viral load - less than 200 copies in the bloodstream per milliliter of blood. Contributing to this low percentage is the fact that an estimated 1 in 5 people with HIV don't realize they they are infected and of those that are aware, only 51% receive medical care and treatment. Modern day treatment, while not eliminating HIV, is very effective in controlling the virus - 77% of those on ongoing care and antiretrovirals have suppressed levels of the virus. [Although couldn't this be from the latent nature of the infection too?]

According to this article, not only are men who have sex with men are the population most severely affected by HIV in the US, they are less likely than other sex-groups to get tested and receive preventative testing. In response to this data, the CDC have launched a new national campaign to encourage black gay and bisexual men to get tested for HIV called Testing Makes Us Stronger. Research shows that black men do not engage in riskier sexual behavior than other LGBT communities, but that there is already a higher HIV presence in their population - so testing, behavior improvement (condoms, e.g.) and appropriate medical care are especially important in these communities. This is the latest campaign in the Act Against AIDS, the CDC's broad effort to fight HIV complacency nationwide.

read the full article here.

Emily Pollock

Hep C updates

The Montefiore Medical Center in New York is now urging members of the baby boomer population to get tested for hepatitis C, as they are more likely to have shared unsanitary needles because of tattoos, drug use, piercings or blood transfusions. Hep C can be asymptomatic for years, and the worry is that many people from this generation might be carrying the virus without knowing it. With a blood test and treatment from two new drugs that were released last May, doctors are seeing almost double the cure rate of the disease as they have in the past. There is still no vaccine to prevent the infection and, if left untreated, hep C can lead to liver failure or cancer, which is why doctors are pushing for people to get tested.

In other Hep C news, this week Delhi became the first city in India to offer Hepatitis C screening. Additionally, the government is offering to provide financial help to poor citizens who need a liver transplant as a result of Hep C.

-Emily Mitchell

Cold Sore Susceptibility Gene-1

Cold sores are lesions around the mouth, lips, nose, and even chin and fingers caused by an infection of the herpes simplex type 1 virus. Over 70% of the population is infected with this virus with outbreaks varying from person to person. These outbreaks are a direct result of the virus remaining in the body and unpredictably causing an immune response (the sores). Although there is no treatment for the virus, there are medications that help treat the cold sores. This reality, however, may soon change.

A recent study published in the Journal of Infectious Diseases identified a 3-megabase region on human chromosome 21 that contains 6 candidate genes associated with cold sores through the use of single nucleotide polymorphism scans. A two-point linkage analysis resulted in a positive correlation between the frequency of cold sore outbreaks and 2 SNP's within the C21orf91 region. The researchers even proposed that C21orf91 be defined as the Cold Sore Susceptibility Gene-1.

C21orf91 in no way increases your chances of being infected with herpes simplex virus 1 in the first place, it is simply correlated with the frequency of cold sore outbreaks. Genetics, according to an infectious disease professor, Dr. Kriesel, are only responsible for 21% of the cold sore outbreaks- the remaining 79% is attributed to environmental factors, the viral strain, and a number of other variables.

Kriesel, John D et al. C21orf91 Genotypes Correlate With Herpes Simplex Labialis (Cold Sore) Frequency: Description of a Cold Sore Susceptibility Gene. J Infect Dis. (2011) 204 (11): 1654-1662.

-Angela CeseƱa

Another Wakefield?

Malcolm Brabant, a BBC reporter, was believed to have a psychotic episode after getting a yellow fever vaccine. It's reported that he had a fever of 40C after the injection followed by delusions of being Jesus. Eventually, he's forced to go off air to recover. No one in his family history had any mental illness.

I thought the beginning of the article was interesting - describing the reporteras "award-winning" and juxtaposing that with the yellow fever psychosis. This puts vaccines in a bad light and may prompt other people to reject vaccination. Although the article mentions that no causal relationship was drawn between the vaccine and his psychosis, the title and the majority of the paper implies this.

-Michelle Jin


WHO Concerned Over a New Flu Virus Spreading From Pigs to Humans

After criticism in Europe that the World Health Organization claimed 2009's swine flu to be a pandemic when in fact the outbreak was comparatively mild, the WHO is being cautious in raising alarm to a new flu virus that has been spreading from pigs to humans. It is an Influenza A virus of the H3N2 subtype, but sufficiently different from current viruses that the H3N2 component of the flu vaccine is not expected to help protect against this new strain.

10 outbreaks of the strain have been isolated in Maine, Indiana, Pennsylvania, and Iowa. In each case, the patient was a child under 10 (with one exception of a 58-year old). This might be because most 21-year-olds (and older) are likely to have had exposure to similar viruses in the past and therefore have a degree of immunity. In the first 7 infections, the virus passed from pigs to humans, but the last 3 cases (in Iowa) were clear cases of human-to-human transmission.

Immunity among the older population would likely prevent the virus from ever becoming a full-blown pandemic, but there is still a possibility the virus could spread child-to-child across countries. The CDC is currently conducting serological research to determine specific vulnerability to the virus; it has also asked the manufacturers who produce seed strains for vaccine companies to produce a vaccine candidate for this new H3N2 strain. WHO is also in the process of devising a name for the virus such that it wouldn't be a problem for any specific agricultural interests (as was the case with objections to the name "swine flu").

I think the proper steps are being taken in regard to the emergence of this new strain - both in developing a preemptive vaccine and in creating a epidemiological system of how to handle the spread of the virus in the chance of increased transmissibility. My personal opinion is that it's also better to be on the safe side and have the general population overly cautious of the virus, rather than to be too worried of garnering criticism and therefore not mounting enough of a response soon enough.

Article here:

-Elena Higuchi

Green tea has superpowers against Hepatitis C?

In a recent study published in the December issue of Hepatology, German scientists from the Hannover Medical School have determined that a certain flavonoid, which is a class of plant secondary metabolites, called EGCG (epigallocatechin-3-gallate), may have a significant role in preventing the Hepatitis C virus from entering liver cells. Their findings could have incredible impacts on the lives of liver transplant patients, who are always at high risk for HCV infection (which according to WHO, affects up to 170 million people worldwide and is the most common cause of chronic liver disease/hepatitis, cirrhosis, and hepatocellular carcinoma). Using EGCG for this particular case may therefore become an important antiviral strategy for the prevention of HCV reinfection following liver transplants.

According to these researchers, "[Their] study explored the potential effect these flavonoids have in preventing HCV reinfection following liver transplantation.” They not only found that this antioxidant EGCG inhibits HCV entry into the cells by inhibiting viral attachment to the cell (which is the initial step in the infection process), but also viewed that the application of this molecule during inoculation prevented the rapid "spread" of the Hepatitis C virus. They specifically announced that "pretreatment of cells with EGCG before HCV inoculation did not reduce the infection, however, application during inoculation inhibited the rapid spread of the HCV."

The actual mechanism of this process however is still in the "uncertain" stage. The authors have suggested that EGCG may actually be preventing the Hepatitis C virus' entry by acting on the host cell, as opposed to acting on the virus, as the green tea catechin was not found to alter the density of virus particles.

Nevertheless, this could have huge implications on future treatments of patients susceptible to chronic hepatitis, primary liver cancer or those who have just received liver transplants. Go green tea!!

- Julie Saffarian

Saturday, December 3, 2011

Who Says Curing AIDs is Impossible?

What is one lesson that Dr. Bob has taught us this year? If people say something is impossible, perhaps it just has not been done yet. A recent article in the New York Times expand on the idea that finding a cure for HIV (something that is usually thought to have insurmountable challenges) may not be as far away as we think.

In 2008 a patient dubbed the “Berlin Patient” was HIV positive when he was diagnosed and treated for leukemia. He was treated with bone marrow transplants which effectively replaced his immune system with the donor’s immune system. It just so happened that his donor was one of Northern Europe’s 1% that are resistant to HIV because they lack CCR5, the human receptor for HIV that allows them to enter immune cells. With his immune system effectively replaced with an HIV resistant immune system, the Berlin Patient has been able to survive 4 years supposedly virus free.

With this knowledge scientists are trying to develop a therapy similar to the Berlin Patient’s treatment for HIV. However, bone marrow transplants are expensive, risky, and require a donor with immunologically matching bone marrow. All this makes it a very tricky process.

Nevertheless, scientists have come up with a plan: “modify a patient’s own immune cells to make them resistant to infection by eliminating CCR5” (NYTimes). Now they have succeeded in doing just that in a patient.

The Trenton patient’s white blood cells were treated with gene therapy to produce zinc-finger nucleases that effectively disrupt CCR5 gene. The treated cells were returned to the patient and a month later he stopped taking his anti-virals.

At first, the level of HIV in his body increased sharply. However, then it fell back to undetectable amounts even before the 12-week period had ended. The patient’s immune cell counts also shot up.

What’s remarkable is that only a portion of his cells became genetically altered after the treatment and it still worked. It’s amazing that it worked at all because most of his CD4 cells had CCR5 gene expression.

Five other patients who received the same treatment did not have such successful outcomes but it is an interesting start to a possible new treatment for the disease. What is most interesting is that some scientists think that getting rid of as little as 10% of CD4 CCR5 gene expression (and therefore saving them from infection) could free up the immune system to control the virus. Patients who genetically have a percentage of their immune that are resistant to HIV (lack CCR5) would be even more likely to overcome disease by this treatment.

The article, New Hope of a Cure for H.I.V. can be found at

--Elena Jordan