cheers,
rohan
Wednesday, November 18, 2009
Theydenovirus
Some interesting news about using adenovirus to deliver HIV (and other) vaccines. Seems not to work:
Saturday, October 10, 2009
Wednesday, September 30, 2009
With the new vaccine on its way....
Interesting take on how vaccines may change long-held attitudes (or how they should)-
http://www.nytimes.com/2009/09/29/health/views/29essa.html?_r=1&ref=health&pagewanted=print
Pregnancy Is No Time to Refuse a Flu Shot
By ANNE DRAPKIN LYERLY, MARGARET OLIVIA LITTLE and RUTH R. FADEN
This article is by Anne Drapkin Lyerly, Margaret Olivia Little and Ruth R. Faden.
Pregnant women are deluged with advice about things to avoid: caffeine, paint, soft cheese, sushi. Even when evidence of possible harm is weak or purely theoretical, the overriding caveat is, “Don’t take it, don’t use it, don’t do it.”
In a few contexts, the admonition is warranted; in most, it is merely inconvenient and anxiety provoking. But in the case of pandemic influenza, it may be deadly. With the second wave of swine flu at hand, and up to 50 percent of the public at risk, the usual mode of thinking about pregnancy and medications threatens to make a worrisome situation worse.
The dangers of this mentality became frighteningly apparent this summer, when a study in The Lancet reported strikingly high rates of death and of complications like pneumonia in pregnant women with H1N1 influenza. Pregnancy meant a fourfold risk of hospitalization, sometimes with a tragic outcome; all the pregnant women who died had been relatively healthy to begin with.
The Centers for Disease Control and Prevention have since put pregnant women at the top of the priority list for the vaccine, and have recommended that pregnant women start antiviral medications as soon as possible after exposure to the virus and after the onset of flu symptoms.
But if experience is any indication, even these forceful recommendations may not be enough to overcome reluctance among pregnant women and those who care for them. Even though the seasonal flu vaccine is recommended for pregnant women in particular, in one study only 15 percent received the vaccine — a rate far lower than any adult group for whom it is recommended.
And despite recommendations that antiviral drugs be started as soon as flu symptoms appear, many pregnant women in the Lancet study were not treated soon enough. Delays ranged from 6 to 15 days from the time that symptoms started, and 2 to 14 days from the time the women were seen by a doctor. Not one of the six pregnant and relatively healthy women who died received medication within 48 hours of the onset of her illness.
This is a sadly familiar pattern. After the thalidomide disaster of 1960s, and the very real concerns it raised about the impact of drugs on fetal development, many ended up viewing the use of any medicine by pregnant women as anathema. As a result, doctors and women alike often eschew or discontinue medications for serious illnesses, even when the harms of untreated disease, for women and the children they bear, are worse than any risks of medication.
Poorly treated asthma during pregnancy, for example, is associated with higher rates of pregnancy complications for women, as well as growth problems in the fetus and premature delivery. By contrast, women whose asthma is controlled with medication do as well as women without asthma, and so do their babies. Untreated diabetes early in pregnancy elevates the chances of severe birth defects to as high as 1 in 4.
And yet even when the evidence is clear, pregnant women find it hard to fight against the “don’t take it, don’t use it, don’t do it” mentality, which focuses our minds and emotions only on the risks of taking a drug. Obscured from view are the risks of the disease itself.
Overcoming this mindset will take work on several fronts. Every effort needs to be made to alert pregnant women and clinicians about the special risks of H1N1 in pregnancy. Educational efforts need to be honest about the reasoning behind these important recommendations, including both the limits of what we know and the reasons that concern for pregnant women is now so great.
But the key to success, now and in the future, will be the conduct of research that is specific to the needs of pregnant women. Concerns about the ethics of research involving these women mean that we know far less about how to treat or prevent disease during pregnancy than for other adults and children. The urgent threat of H1N1 flu has brought into sharp relief the fact that pregnant women can and should be protected through research, not from it.
Studies enrolling pregnant women in trials of vaccines for swine flu, financed by the National Institute of Allergy and Infectious Diseases, are now under way at six major medical centers. Researchers are also studying ways to guide the use of antiviral drugs to suit pregnant women’s changed metabolisms. Experts suggest that studying blood samples from as few as two dozen women is all we need to determine whether the standard adult dose of antivirals is effective for treatment or protection during pregnancy.
If there was ever a time to rewrite the playbook on how to think about drugs, vaccines and pregnancy, this is it. The lives of women and babies depend on it.
http://www.nytimes.com/2009/09/29/health/views/29essa.html?_r=1&ref=health&pagewanted=print
Pregnancy Is No Time to Refuse a Flu Shot
By ANNE DRAPKIN LYERLY, MARGARET OLIVIA LITTLE and RUTH R. FADEN
This article is by Anne Drapkin Lyerly, Margaret Olivia Little and Ruth R. Faden.
Pregnant women are deluged with advice about things to avoid: caffeine, paint, soft cheese, sushi. Even when evidence of possible harm is weak or purely theoretical, the overriding caveat is, “Don’t take it, don’t use it, don’t do it.”
In a few contexts, the admonition is warranted; in most, it is merely inconvenient and anxiety provoking. But in the case of pandemic influenza, it may be deadly. With the second wave of swine flu at hand, and up to 50 percent of the public at risk, the usual mode of thinking about pregnancy and medications threatens to make a worrisome situation worse.
The dangers of this mentality became frighteningly apparent this summer, when a study in The Lancet reported strikingly high rates of death and of complications like pneumonia in pregnant women with H1N1 influenza. Pregnancy meant a fourfold risk of hospitalization, sometimes with a tragic outcome; all the pregnant women who died had been relatively healthy to begin with.
The Centers for Disease Control and Prevention have since put pregnant women at the top of the priority list for the vaccine, and have recommended that pregnant women start antiviral medications as soon as possible after exposure to the virus and after the onset of flu symptoms.
But if experience is any indication, even these forceful recommendations may not be enough to overcome reluctance among pregnant women and those who care for them. Even though the seasonal flu vaccine is recommended for pregnant women in particular, in one study only 15 percent received the vaccine — a rate far lower than any adult group for whom it is recommended.
And despite recommendations that antiviral drugs be started as soon as flu symptoms appear, many pregnant women in the Lancet study were not treated soon enough. Delays ranged from 6 to 15 days from the time that symptoms started, and 2 to 14 days from the time the women were seen by a doctor. Not one of the six pregnant and relatively healthy women who died received medication within 48 hours of the onset of her illness.
This is a sadly familiar pattern. After the thalidomide disaster of 1960s, and the very real concerns it raised about the impact of drugs on fetal development, many ended up viewing the use of any medicine by pregnant women as anathema. As a result, doctors and women alike often eschew or discontinue medications for serious illnesses, even when the harms of untreated disease, for women and the children they bear, are worse than any risks of medication.
Poorly treated asthma during pregnancy, for example, is associated with higher rates of pregnancy complications for women, as well as growth problems in the fetus and premature delivery. By contrast, women whose asthma is controlled with medication do as well as women without asthma, and so do their babies. Untreated diabetes early in pregnancy elevates the chances of severe birth defects to as high as 1 in 4.
And yet even when the evidence is clear, pregnant women find it hard to fight against the “don’t take it, don’t use it, don’t do it” mentality, which focuses our minds and emotions only on the risks of taking a drug. Obscured from view are the risks of the disease itself.
Overcoming this mindset will take work on several fronts. Every effort needs to be made to alert pregnant women and clinicians about the special risks of H1N1 in pregnancy. Educational efforts need to be honest about the reasoning behind these important recommendations, including both the limits of what we know and the reasons that concern for pregnant women is now so great.
But the key to success, now and in the future, will be the conduct of research that is specific to the needs of pregnant women. Concerns about the ethics of research involving these women mean that we know far less about how to treat or prevent disease during pregnancy than for other adults and children. The urgent threat of H1N1 flu has brought into sharp relief the fact that pregnant women can and should be protected through research, not from it.
Studies enrolling pregnant women in trials of vaccines for swine flu, financed by the National Institute of Allergy and Infectious Diseases, are now under way at six major medical centers. Researchers are also studying ways to guide the use of antiviral drugs to suit pregnant women’s changed metabolisms. Experts suggest that studying blood samples from as few as two dozen women is all we need to determine whether the standard adult dose of antivirals is effective for treatment or protection during pregnancy.
If there was ever a time to rewrite the playbook on how to think about drugs, vaccines and pregnancy, this is it. The lives of women and babies depend on it.
Monday, August 3, 2009
New Strain of HIV Discovered
New HIV strain discovered in woman from Cameroon
WASHINGTON — A new strain of the virus that causes AIDS has been discovered in a woman from the African nation of Cameroon. It differs from the three known strains of human immunodeficiency virus and appears to be closely related to a form of simian virus recently discovered in wild gorillas, researchers report in Monday's edition of the journal Nature Medicine.
The finding "highlights the continuing need to watch closely for the emergence for new HIV variants, particularly in western central Africa," said the researchers, led by Jean-Christophe Plantier of the University of Rouen, France.
The three previously known HIV strains are related to the simian virus that occurs in chimpanzees.
The most likely explanation for the new find is gorilla-to-human transmission, Plantier's team said. But they added they cannot rule out the possibility that the new strain started in chimpanzees and moved into gorillas and then humans, or moved directly from chimpanzees to both gorillas and humans.
The 62-year-old patient tested positive for HIV in 2004, shortly after moving to Paris from Cameroon, according to the researchers. She had lived near Yaounde, the capital of Cameroon, but said she had no contact with apes or bush meat, a name often given to meat from wild animals in tropical countries.
The woman currently shows no signs of AIDS and remains untreated, though she still carries the virus, the researchers said.
How widespread this strain is remains to be determined. Researchers said it could be circulating unnoticed in Cameroon or elsewhere. The virus' rapid replication indicates that it is adapted to human cells, the researchers reported.
Their research was supported by the French Health Watch Institute, the French National Agency for Research on AIDS and Viral Hepatitis and Rouen University Hospital.
A separate paper, also in Nature Medicine, reports that people with genital herpes remain at increased risk of HIV infection even after the herpes sores have healed and the skin appears normal.
Researchers led by Drs. Lawrence Corey and Jia Zhu of the Fred Hutchinson Cancer Research Center found that long after the areas where the herpes sores existed seem to be clear, they still have immune-cell activity that can encourage HIV infection.
Herpes is marked by recurring outbreaks and has been associated with higher rates of infection with HIV. It had been thought that the breaks in the skin were the reason for higher HIV rates, but a study last year found that treatment of herpes with drugs did not reduce the HIV risk.
The researchers tested the skin of herpes patients for several weeks after their sores had healed and found that, compared with other genital skin, from twice to 37 times more immune cells remained at the locations where the sores had been.
HIV targets immune cells and in laboratory tests the virus reproduced three to five times faster in tissue from the healed sites as in tissue from other areas.
"Understanding that even treated (herpes) infections provide a cellular environment conducive to HIV infection suggests new directions for HIV prevention research," commented Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Disease.
That study was funded by the National Institutes of Health and the Tietze Foundation.
-Nick
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