Researchers from Johns Hopkins recently analyzed several studies of flu vaccination efficacy and concluded that while the vaccines are said to protect 70-90% of the population, in reality, they are only effective in 59%. They analyzed 17 randomized controlled trials and 14 observational studies from 1967-2011. Their conclusions include: efficacy of TIV in only 59% of adults aged 18-65 no such trials for children ages 2-17 or people over 65 fit the criteria for their study; efficacy of LAIV in 83% of children 6months - 7 years and no such trials for ages 8-17; no LAIV studies demonstrated significant protection in healthy adults under 60
One of the researchers argued for reduction of regulatory barriers, stating that,
"'The difference between 69% effectiveness and 90% effectiveness will have a major public health effect in any pandemic that causes serious morbidity or increased mortality.'"
An interesting note is that the researchers only deemed 31 out of 5,707 studies screened as eligible to analyze. They chose to only include studies that used highly specific tests like RT-PCR to confirm the presence of flu and excluded studies on the basis of study design. It is admirable that they had such stringent requirements for their analysis, but that also means they looked at less than 1% of the available studies that have been done in the past 40 years. Are they skewing theirs numbers by being too picky?
http://www.medicalnewstoday.com/articles/236585.php
-Emily Mitchell
Monday, October 31, 2011
No more cold sores?
Researchers at Utah identified a gene linked to Herpes Simplex labialis (Cold sore). This type of herpes infection results in fluid-filled blisters on the tips and the virus remains in the body throughout the infected person's life time. In a study with 618 participants who had cold sores, the researchers identified a gene called C21orf91 that is responsible for cold sores. Researchers suggest that the gene will be remained as the Cold Sore Susceptibility Gene 1 (woo so much easier to remember!). This discovery has important implications for drugs for the treatment of cold sores and future research on whether it's linked genital herpes.
I think this is a very interesting finding because although cold sores are not as severe as other herpes infections, it is very annoying to have to deal with them. Having had cold sores my whole life, I'm very excited to hear that there might be new long lasting treatments that might prevent future outbreaks.
-Michelle Jin
Link: http://www.presstv.ir/detail/207498.html
I think this is a very interesting finding because although cold sores are not as severe as other herpes infections, it is very annoying to have to deal with them. Having had cold sores my whole life, I'm very excited to hear that there might be new long lasting treatments that might prevent future outbreaks.
-Michelle Jin
Link: http://www.presstv.ir/detail/207498.html
Sunday, October 30, 2011
Successful Application of Sterile Insect Technique to Aedes Aegypti Mosquitoes, But Concerns Raised Over Public Reception
Today, the New York Times reported on the publication of a paper in the journal Nature Biotechnology that reports success in the release of large numbers of effectively sterile, male mosquitoes in the Cayman Islands to control the population of the Aedes Aegypti mosquito. Using genetic modification to make the male mosquitoes and any subsequent offspring dependent on doses of tetracycline, researchers working for the company Oxitec hoped that their modified crop would compete with natural males and give rise to a generation of new mosquitoes that would die before birth. Since female mosquitoes only mate once, this technique has to potential to seriously curtail mosquito population and, by association, the risk of spreading diseases such as dengue that use these mosquitoes as vectors.
The same technique has already been used successfully in multiple cases to limit or even eradicate entire insect populations, such as the screw-fly in most of North America. Those cases relied instead on ionizing radiation to sterilize males and/or female flies with the rest of the protocol unchanged. Unfortunately, such techniques can't be applied here since irradiated flies maintain their ability to compete with natural males, something not seen in Aedes aegypti mosquitoes. Indeed, researchers were pleased to attain a 50% competition rate in the studies conducted so far, with the release of enough males to approximate 16 % of the total population having the lethal gene resulting in 10% of larva dying in one example.
Unfortunately, numbers like this form one point of possible controversy. Like with the screw-fly program, an eventual program to eradicate or seriously control the mosquito will have to rely on 'over-kill', with tremendous amounts of modified mosquitoes being released. Given a 3.5% rate of offspring mutating to survive the presence of the gene and a 0.5% rate of females accidentally released alongside the males, programs such as this carry the risk of unintentionally making the situation worse if major errors occur. What may influence public perception the most is that this program involves “genetic modification” and the introduction of vast numbers of modified organisms into the environment. Even if similar programs have been performed with incredible success for decades, these projects needs to be handled with care, lest a public backlash prevent the control of such a deadly pest.
New York Times Article:
Concerns Are Raised About Genetically Modified Mosquitoes
http://www.nytimes.com/2011/10/31/science/concerns-raised-about-genetically-engineered-mosquitoes.html?pagewanted=2&_r=1
Sterile Insect Technique:
http://en.wikipedia.org/wiki/Sterile_insect_technique
Screwworm Eradication in North and Central America(1987)
http://www.sciencedirect.com/science/article/pii/0169475887901967
-Zachary Herrera
The same technique has already been used successfully in multiple cases to limit or even eradicate entire insect populations, such as the screw-fly in most of North America. Those cases relied instead on ionizing radiation to sterilize males and/or female flies with the rest of the protocol unchanged. Unfortunately, such techniques can't be applied here since irradiated flies maintain their ability to compete with natural males, something not seen in Aedes aegypti mosquitoes. Indeed, researchers were pleased to attain a 50% competition rate in the studies conducted so far, with the release of enough males to approximate 16 % of the total population having the lethal gene resulting in 10% of larva dying in one example.
Unfortunately, numbers like this form one point of possible controversy. Like with the screw-fly program, an eventual program to eradicate or seriously control the mosquito will have to rely on 'over-kill', with tremendous amounts of modified mosquitoes being released. Given a 3.5% rate of offspring mutating to survive the presence of the gene and a 0.5% rate of females accidentally released alongside the males, programs such as this carry the risk of unintentionally making the situation worse if major errors occur. What may influence public perception the most is that this program involves “genetic modification” and the introduction of vast numbers of modified organisms into the environment. Even if similar programs have been performed with incredible success for decades, these projects needs to be handled with care, lest a public backlash prevent the control of such a deadly pest.
New York Times Article:
Concerns Are Raised About Genetically Modified Mosquitoes
http://www.nytimes.com/2011/10/31/science/concerns-raised-about-genetically-engineered-mosquitoes.html?pagewanted=2&_r=1
Sterile Insect Technique:
http://en.wikipedia.org/wiki/Sterile_insect_technique
Screwworm Eradication in North and Central America(1987)
http://www.sciencedirect.com/science/article/pii/0169475887901967
-Zachary Herrera
Saturday, October 29, 2011
Antibody Vaccine Shows Promise for Nipah and Hendra
A new monoclonal antibody vaccine that protects against two paramyxoviridae viruses - Nipah and Hendra - has shown promise in clinical trials involving monkeys. The NIH stated that in all 12 trials, the monkeys received lethal doses of the Hendra virus and were subsequently given the antibody vaccine, and all 12 monkeys recovered.
Nipah is a deadly disease that has killed 251 of the 475 people known to have been infected with it (most of whom worked with pigs); the movie Contagion was based upon the Nipah virus. Hendra has only been known to have infected 7 people (4 cases were fatal), but this preliminary vaccine may also have saved the lives of an Australian mother and daughter who were sick with the virus. Antibodies are relatively expensive to produce, however, so scientists are also looking into the possibility of peptide vaccines for the two diseases - an option which has shown promise among hamsters.
I find this an interesting progress because it's vital that we research vaccines for not only the traditional headliner viruses (HIV, ebola, etc), but even those that occur less commonly. Nipah and Hendra may not be household names, but given how quickly swine flu mutated from an infection among pigs to one that could be readily transmissible among humans, it's quite possible that these deadly diseases could quickly mutate to become much more widespread. If such a scenario ever occurs, it would be hugely beneficial to already have a template vaccine available to work with.
Original article: http://www.nytimes.com/2011/10/25/health/25global.html?scp=1&sq=viruses&st=cse
- Elena Higuchi
Nipah is a deadly disease that has killed 251 of the 475 people known to have been infected with it (most of whom worked with pigs); the movie Contagion was based upon the Nipah virus. Hendra has only been known to have infected 7 people (4 cases were fatal), but this preliminary vaccine may also have saved the lives of an Australian mother and daughter who were sick with the virus. Antibodies are relatively expensive to produce, however, so scientists are also looking into the possibility of peptide vaccines for the two diseases - an option which has shown promise among hamsters.
I find this an interesting progress because it's vital that we research vaccines for not only the traditional headliner viruses (HIV, ebola, etc), but even those that occur less commonly. Nipah and Hendra may not be household names, but given how quickly swine flu mutated from an infection among pigs to one that could be readily transmissible among humans, it's quite possible that these deadly diseases could quickly mutate to become much more widespread. If such a scenario ever occurs, it would be hugely beneficial to already have a template vaccine available to work with.
Original article: http://www.nytimes.com/2011/10/25/health/25global.html?scp=1&sq=viruses&st=cse
- Elena Higuchi
Wednesday, October 26, 2011
Herpesvirus as breast cancer treatment
Sloan-Kettering Cancer Center: A herpesvirus engineered to specifically target triple-negative breast cancer cells is showing promise in in vitro studies. This type of breast cancer causes 20% of cases but isn't estrogen-receptor dependent, and thus can't be targeted by those drugs. However, these cancers have high levels of pMAPK, a phosphorylated signal cascade protein. The herpesvirus attacks these cells, shown up to 90% effective in petri dishes and in mouse models.
This is pretty cool, especially if it's replicable in humans. I'm not sure I understand the biology (how does the intracellular levels of pMAPK make a difference to the virus? I would have thought that the virus would be targeted to a specific cell surface receptor for entry). However, a few key properties will probably be interesting clinically, based on what we know about these viruses.
1. Herpesvirus causes local infection. That means that it can be specifically targeted to the cancer site, but also that it may not work for metastases.
2. Herpesviruses are latent. Does this mean that they'll stick around to screw up the patient later, or perhaps provide lasting protection against recurring cancer?
In any case, it's been an exciting time for herpesviruses—Alzheimer cause, cure for cancer? Also, we need a new "chemotherapy" term for viruses. "Vironcotherapy?"
Article here.)
-Annelise Mah
This is pretty cool, especially if it's replicable in humans. I'm not sure I understand the biology (how does the intracellular levels of pMAPK make a difference to the virus? I would have thought that the virus would be targeted to a specific cell surface receptor for entry). However, a few key properties will probably be interesting clinically, based on what we know about these viruses.
1. Herpesvirus causes local infection. That means that it can be specifically targeted to the cancer site, but also that it may not work for metastases.
2. Herpesviruses are latent. Does this mean that they'll stick around to screw up the patient later, or perhaps provide lasting protection against recurring cancer?
In any case, it's been an exciting time for herpesviruses—Alzheimer cause, cure for cancer? Also, we need a new "chemotherapy" term for viruses. "Vironcotherapy?"
Article here.)
-Annelise Mah
Breakthrough that may help combat viral infections like HIV
After a whole week on the cells of the immune system, it is exciting to come across an article that describes the use of our own Natural Killer cells' properties to combat serious infections such as HIV.
Natural Killer cells are a type white blood cells or lymphocytes that are an important component of our innate immune system. They are not activated by molecules found on a tumor or a pathogen unlike most other cells, but are rather "shut down" by proteins, called Human Leukocyte Antigens (HLA) found on our healthy cells. Since tumor cells and pathogens lack these HLAs, they are immediately killed by Natural Killer cells, (since they are not shut down like with our healthy cells.)
Natural Killer cells recognise the HLA molecules on our cells using a system called "Killer cell immunoglobulin-like receptors" (KIR). This pairing is known to play a role in limiting viral replication in people with HIV, slowing the progression of the disease to AIDS. The exact mechanism is unknown, but it has been suggested that a better understanding of the structure of the KIR proteins may help to develop new ways of using Natural Killer cells against viral infection.
This is another promising piece of good news for the fight against HIV!
- Julie Saffarian
Natural Killer cells are a type white blood cells or lymphocytes that are an important component of our innate immune system. They are not activated by molecules found on a tumor or a pathogen unlike most other cells, but are rather "shut down" by proteins, called Human Leukocyte Antigens (HLA) found on our healthy cells. Since tumor cells and pathogens lack these HLAs, they are immediately killed by Natural Killer cells, (since they are not shut down like with our healthy cells.)
Natural Killer cells recognise the HLA molecules on our cells using a system called "Killer cell immunoglobulin-like receptors" (KIR). This pairing is known to play a role in limiting viral replication in people with HIV, slowing the progression of the disease to AIDS. The exact mechanism is unknown, but it has been suggested that a better understanding of the structure of the KIR proteins may help to develop new ways of using Natural Killer cells against viral infection.
This is another promising piece of good news for the fight against HIV!
- Julie Saffarian
Monday, October 24, 2011
Hearth Trouble Linked to HPV?!!
A study of 2,450 women by Dr. Kenichi Fujise of University of Texas is making yet another claim against the highly talked about HPV. His study has produced findings that suggest women infected with HPV are two to three times more likely to have a heart attack or stoke.
Earlier we talked about how HPV is a known cause of cancer of the cervix, anus and throat. It can also cause cancer of the vulva and penis. While this study does not prove that HPV is linked to heart disease it shows a strong link between the two. The researcher suspect that HPV, with its ability to sabotage the P53 gene, could possibly lead to inflammation and thickening of the arterial walls.
Clearly, more research needs to be done to determine if this link between HPV and heart disease is really causative and also if it is causative in men as well. If it is, this would lead to ever more reason for more people (men and women) to get the HPV vaccine. It also might signal that a paradigm shift about the vaccine is needed as more health concerns become linked with this virus.
Read more at:
http://www.nytimes.com/2011/10/25/health/research/25theory.html?ref=health#
--Elena Jordan
Earlier we talked about how HPV is a known cause of cancer of the cervix, anus and throat. It can also cause cancer of the vulva and penis. While this study does not prove that HPV is linked to heart disease it shows a strong link between the two. The researcher suspect that HPV, with its ability to sabotage the P53 gene, could possibly lead to inflammation and thickening of the arterial walls.
Clearly, more research needs to be done to determine if this link between HPV and heart disease is really causative and also if it is causative in men as well. If it is, this would lead to ever more reason for more people (men and women) to get the HPV vaccine. It also might signal that a paradigm shift about the vaccine is needed as more health concerns become linked with this virus.
Read more at:
http://www.nytimes.com/2011/10/25/health/research/25theory.html?ref=health#
--Elena Jordan
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