Tuesday, August 31, 2010
Michael Carter for Aidsmap (31 August 2010 )
Many HIV-positive patients do not develop protective antibody levels after receiving the standard dose of the swine flu vaccine, a study published in the September 10th edition of AIDS shows. A low current CD4 cell count was the only factor associated with a poor response to the vaccine.
“The implications of this research are immediate for next year’s influenza vaccination campaign”, comment the investigators. “Our results suggest that if that vaccine is used at the currently recommended dose, a significant proportion of individuals will remain vulnerable to influenza”.
It is recommended that all HIV-positive patients should receive the seasonal flu vaccine. In 2009 the H1N1 (swine flu) virus was identified and the World Health Organization declared a global flu pandemic. A vaccine against the virus was developed and people with underlying health conditions – including HIV - were recommended to receive this.
Investigators from the University of Pennsylvania wished to see if the vaccine produced protective antibody levels in HIV-positive patients. The safety of the vaccine was also monitored.
“Up to 40% of HIV-positive individuals are not seroprotected after vaccination”, write the investigators.
“The presence of other underlying chronic diseases, medication use, poor nutrition, irreversible damage to the immune system and immunosenescence [decline of the immune system due to ageing], likely all play a role in decreased vaccine responsiveness in spite of successful treatment of the HIV infection”, they add.
A number of strategies are suggested by the researchers to enhance the response rate to the vaccination. These include the use of alternative vaccines; increasing the dose; the use of adjuvants; and the use of live vaccines.
The authors of an accompanying editorial note the findings of the study, emphasizing “suboptimal vaccine efficacy in HIV-infected persons represents a clinically important matter. Current evidence evaluating influenza vaccination efficacy in the HIV population remains insufficient”.
Poor immunogenicity of the H1N1 209 vaccine in well controlled HIV-infected individuals.
Tebas, Pablo; Frank, Ian; Lewis, Mark; Quinn, Joseph; Zifchak, Larisa; Thomas, Aleshia; Kenney, Thomas; Kappes, Rosemary; Wagner, Wayne; Maffei, Kathy; Sullivan, Kathleen; the Center for AIDS Research and Clinical Trials Unit of the University of Pennsylvania.
AIDS 24: 2187-2192, September 10, 2010. doi: 10.1097/QAD.0b013e32833c6d5c
Link to AIDS abstract
Editorial: Preventing influenza coinfection among HIV-infected persons: a complex picture coming into focus.
Reyes-Teran, Gustavo; Butera, Salvatore T
AIDS 24: 2283-85, , September 10, 2010. doi: 10.1097/QAD.0b013e32833dbcd2.
Link to AIDS editorial
Vaccination Should Be Requirement for Continued Employment for Healthcare Personnel, Epidemiologists and Infectious Disease Physicians Say
— Influenza vaccination of healthcare personnel is a professional and ethical responsibility and non-compliance with healthcare facility policies regarding vaccination should not be tolerated, according to a position paper released by the Society for Healthcare Epidemiology of America (SHEA). The paper, published in this month's Infection Control and Healthcare Epidemiology journal and endorsed by the Infectious Diseases Society of America (IDSA), stresses influenza vaccination of healthcare personnel as a core patient safety practice that should be a condition of both initial and continued employment in healthcare facilities.
According to SHEA, their recommendations apply to all healthcare professionals in all healthcare settings, regardless of whether the professional has direct patient contact or whether he or she is directly employed by the facility. The policy also applies to students, volunteers, and contract workers. The only exemptions, say the epidemiologists and infectious disease physicians, should be in cases of medical contraindications.
"The transmission of influenza in healthcare settings is a substantial safety concern for both patients and healthcare personnel and deserves our attention and action," said Neil Fishman, MD, president of SHEA. "Healthcare providers are ethically obligated to take measures proven to keep patients from acquiring influenza in healthcare settings. Mandatory vaccination is the cornerstone to a comprehensive program designed to prevent the spread of influenza which also includes identification and isolation of infected patients, adherence to hand hygiene and cough etiquette, the appropriate use of protective equipment, and restriction of ill healthcare personnel and visitors in the facility."
The position paper, an update of an original statement issued in 2005, comes as healthcare personnel and facilities prepare for the upcoming 2010 flu season, and on the heels of one of the worst flu seasons in our nation's history, the result of the H1N1 strain. Last year's flu season highlighted the necessity for stronger policies for healthcare personnel influenza vaccination, especially in light of the low vaccination rates in many voluntary influenza vaccination programs.
"Given the debate that surrounded mandatory healthcare personnel vaccination during the last influenza season, we support and applaud SHEA for issuing a strong and unequivocal statement about the critical importance of healthcare personnel vaccination," said Richard Whitley, MD, president of IDSA.
According to a 2009 RAND Corporation survey, 39 percent of healthcare professionals stated they had no intention of getting vaccinated despite the heightened concern surrounding influenza with the H1N1 pandemic.
"The scientific evidence shows significant reductions in the risk of influenza in both acute and long-term care settings as a result of strong immunization policies and programs," Dr. Whitley said. "Vaccination of healthcare personnel saves patients' lives and reduces illness. It also protects the individual worker from falling ill during influenza outbreaks and from missing work, which further impacts patient care." IDSA also supports SHEA's recommendation that a mandatory vaccination program be part of a multi-faceted, comprehensive infection control program.
Fishman added that he believes that this position paper, coupled with full and visible support of mandatory influenza vaccination by healthcare facility leadership, will dramatically improve the rates of vaccination.
Mandatory Influenza Vaccination of Healthcare Workers: A 5‐Year Study
Robert M. Rakita, MD; Beverly A. Hagar, BSN, COHNS; Patricia Crome, MN; Joyce K. Lammert, MD, PhD
From the Sections of Infectious Diseases (R.M.R.), Asthma, Allergy, and Immunology (J.K.L.), Employee Health (B.A.H.), and Administration (P.C.), Virginia Mason Medical Center, Seattle, Washington. (Present affiliations: Division of Allergy and Infectious Diseases, University of Washington [R.M.R.], and Rona Consulting Group [P.C.], Seattle, Washington.)
Infection Control and Hospital Epidemiology, 2010; 31 (9): 881- 888 DOI: 10.1086/656210
Link to ICHE abstract
You can "check in" to restaurants and bars, so how about health clinics while you get tested for sexually transmitted diseases?
Foursquare, the phone application for telling friends and strangers where you are, is offering a special virtual "badge" in September to people who do just that.
The badge is part of MTV's "GYT: Get Yourself Tested" campaign. MTV says the idea is to remove the stigma attached to getting checked out for STDs.
Foursquare and similar services use smart phones' GPS capabilities to locate where users are and what's around them. Users can then "check in" to a venue by tapping it on a list — or typing in their own.
Foursquare users already receive scout-inspired merit badges for a range of check-in accomplishments. These include "Gym Rat" for hitting the gym 10 times in a month or "Crunked" for checking in to four or more places in a single night.
Stephen Friedman, the general manager of MTV, said he expects that some people will decide to get the badge despite the social stigma surrounding STDs. And once they do, their friends may, too.
"It only takes a few to get the ball rolling," he said. The point is to make these checkups as commonplace as going to the dentist or getting a physical.
The badge itself is lime green and black, with the letters "GYT" emblazoned in the middle.
Foursquare users can go to their own health care providers, or they can find nearby clinics by visiting GYT's website and entering their ZIP code. Once they've checked in, users will have to post — or "shout" in Foursquare lingo — the letters "GYT" to their friends.
The GYT campaign launched in 2009. It's part of a partnership between MTV and the Kaiser Family Foundation, a nonprofit organization that focuses on health care issues. MTV said the campaign has helped increase the number of young people getting tested at Planned Parenthood clinics nationwide.
Science Daily (Aug. 31, 2010)
Treatment for S. Aureus Skin Infection Works in Mouse Model
— Scientists from the National Institutes of Health and University of Chicago have found a promising treatment method that in laboratory mice reduces the severity of skin and soft-tissue damage caused by USA300, the leading cause of community-associated Staphylococcus aureus infections in the United States.
By neutralizing a key toxin associated with the bacteria, they found they could greatly reduce the damaging effects of the infection on skin and soft tissue. Community strains of S. aureus cause infection in otherwise healthy people and are considered extremely virulent, as opposed to hospital strains that infect people who already are weakened by illness or surgery.
While much recent attention has been focused on deaths caused by S. aureus infection in the bloodstream -- and those caused by methicillin-resistant S. aureus (MRSA)in particular -- the Centers for Disease Control and Prevention estimates that in 2005, physicians treated 14 million non-lethal S. aureus skin and soft-tissue cases in the United States.
In their study, now online in The Journal of Infectious Diseases, scientists from NIH's National Institute of Allergy and Infectious Diseases (NIAID) examined the effects of the bacterial toxin alpha-hemolysin, or Hla, on S. aureus skin infections in laboratory mice. In all aspects of the study where the Hla toxin was either removed from S. aureus bacteria or neutralized through immunization, skin abscesses were significantly smaller, mice recovered faster and there was little or no skin destruction.
When S. aureus secretes Hla during infection in humans, the toxin pokes holes in a variety of different host cells, killing them. Scientists who have studied Hla for years have mainly focused on neutralizing the toxin in cases of pneumonia-related S. aureus infection. Until now, no one had tested how the absence of Hla would affect the severity of USA300 skin infections and whether immunization against the toxin could neutralize Hla and its contribution to the severity of skin disease.
"For cases of skin and soft-tissue infection caused by Staph aureus, this study highlights the potential for antitoxin treatment to become an effective alternative to traditional antibiotics, which we know have limitations because of drug resistance," says NIAID Director Anthony S. Fauci, M.D. Antitoxins prevent harm caused by a specific part of a pathogen -- such as Hla in S. aureus -- rather than trying to kill the entire pathogen, as antibiotics do.
The study, led by Frank DeLeo, Ph.D., of NIAID's Rocky Mountain Laboratories in Hamilton, Mont., documented physical differences in mice infected with different strains of S. aureus, including USA300 with or without Hla. The second portion of the study tested what is known as active and passive immunity, with mice being immunized with a non-lethal version of the toxin or injected with Hla-specific antibodies, respectively. Both types of immunization protected mice from skin lesions that typically destroy skin and surrounding tissue.
The group noted that multiple S. aureus molecules must contribute to skin infection because simply removing or neutralizing Hla did not completely prevent the formation of skin abscesses, although the abscesses were smaller in size.
Study collaborators from the University of Chicago, Olaf Schneewind, M.D., Ph.D., and Juliane Bubeck Wardenburg, M.D., Ph.D.,contributed the Hla treatment concept, which they developed through their recent work on S. aureus pneumonia. Dr. DeLeo's group adapted that work to their mouse model of skin infection, which is a good indicator of how abscess size and skin destruction could affect humans, according to the study investigators.
"This toxin is probably one of the most promising targets we currently have in our efforts to develop therapeutics that protect against severe Staph aureus skin infections," says Dr. DeLeo. His group is continuing its collaboration with Drs. Schneewind and Bubeck Wardenburg on the project.
1. Targeting of Alpha-Hemolysin by Active or Passive Immunization Decreases Severity of USA300 Skin Infection in a Mouse Model.
Adam D. Kennedy, Juliane Bubeck Wardenburg, Donald J. Gardner, Daniel Long, Adeline R. Whitney, Kevin R. Braughton, Olaf Schneewind, Frank R. DeLeo.
The Journal of Infectious Diseases, 2010; 202 (7): 1050 DOI: 10.1086/656043
Link to JID abstract
2. Vaccine protection against Staphylococcus aureus pneumonia.
Juliane Bubeck Wardenburg and Olaf Schneewind.
Journal of Experimental Medicine, 2008; 205 (2): 287 DOI: 10.1084/jem.20072208
Link to JEM abstract
3. Poring over pores: α-hemolysin and Panton-Valentine leukocidin in Staphylococcus aureus pneumonia.
Juliane Bubeck Wardenburg, Taeok Bae, Michael Otto, Frank R DeLeo, Olaf Schneewind
Nature Medicine, 2007; 13 (12): 1405 DOI: 10.1038/nm1207-1405
Link to Nature Med abstract
By mining data from the 2000 Census, sociologist Michael Rosenfeld figured out the rates at which kids raised by gay and straight couples repeated a grade during elementary or middle school. He found that children of same-sex parents have essentially the same educational achievement as their peers growing up in heterosexual households.
In nearly every discussion, debate or lawsuit about gay marriage, the talk at some point turns to family values.
Do gay couples make for good parents? Will their children -- whether adopted, conceived with the help of a surrogate or brought in from a pre-existing relationship -- adjust, adapt and succeed in a world dominated by traditional families?
The answers usually depend on who's giving them, and come dressed in anecdotes and colored by bias. But Stanford sociologist Michael Rosenfeld brings something new to the conversation: facts and figures derived from the country's largest data bank -- the U.S. Census.
In a study published this month in the journal Demography, Rosenfeld concludes that children being raised by same-sex couples have nearly the same educational achievement as children raised by married heterosexual couples.
By mining data from the 2000 Census, Rosenfeld was able to figure out the rates at which children in all types of families repeated a grade during elementary or middle school. According to his findings, nearly 7 percent of children raised by heterosexual married couples were held back a year, while about 9.5 percent of children living with adults identifying themselves as same-sex partners repeated a grade.
The difference between the groups pretty much vanishes when taking into account that the heterosexual couples were slightly more educated and wealthier than most gay parents, Rosenfeld said.
"The census data show that having parents who are the same gender is not in itself any disadvantage to children," he said. "Parents' income and education are the biggest indicators of a child's success. Family structure is a minor determinant."
Rosenfeld's findings have been cited by lawyers fighting Proposition 8, the gay marriage ban passed by California voters in 2008. A federal court judge recently overturned the ban, but his ruling is under appeal.
Rosenfeld's study shows that children of gay and married couples had lower grade-repetition rates than their peers raised by opposite-sex unmarried couples and single parents. And all children living in some type of family environment did much better than those living in group housing. Those who were awaiting adoption or placement in a foster home were held back about 34 percent of the time.
"One of the fundamental issues in modern family law that differs from state to state is whether same-sex couples can adopt," Rosenfeld said. "My research makes clear that there's a huge advantage to kids to be out of the care of the state and into the care of any family, even if the family is not perfectly optimal."
Educators, policymakers and social scientists have long known that children left back in school are at greater risk than their peers for not finishing high school and getting into trouble.
Because gays and lesbians make up such a tiny sliver of the American population -- only 1 percent -- it has been difficult for researchers to conduct a representative study of how their children perform in the classroom. And gay marriage opponents have criticized earlier studies for having sample sizes that are too small.
"Sample size is power," Rosenfeld said. "And the census is the biggest sample we have. This study is based on a sample of thousands and thousands of kids."
Most personal decisions about gay marriage are based on gut feelings, religious beliefs and individual experiences. Rosenfeld knows his research isn't going to change the minds of most people opposed to same-sex unions. But he has added new data to the debate that helps debunk assertions -- whether based on a lack of knowledge or some unfounded fear -- that children raised by gay couples cannot thrive.
"Social scientists have an obligation to shed light where they can on issues that are roiling the public," he said. "Sometimes we have to throw up our hands and admit that something is unknowable. But in this case, we could bring some real hard data to bear on an area that was otherwise really in the dark."
Nontraditional Families and Childhood Progress Through School.
Michael J. Rosenfeld.
Demography, 2010; 47 (3): 755 – 775 DOI: 10.1353/dem.0.0112
Link to Demography abstract
Science Daily (Aug. 30, 2010)
— The notion that cutting or burning oneself could provide relief from emotional distress is difficult to understand for most people, but it is an experience reported commonly among people who compulsively hurt themselves.
Individuals with borderline personality disorder experience intense emotions and often show a deficiency of emotion regulation skills. This group of people also displays high prevalence rates of self-injurious behavior, which may help them to reduce negative emotional states.
Niedtfeld and colleagues (from the University of Heidelberg and the University of Rostock) studied the effects of emotional stimuli and a thermal stimulus in people either with or without borderline personality disorder. They conducted an imaging study using picture stimuli to induce negative, positive, or neutral affect and thermal stimuli to induce heat pain or warmth perception. The painful heat stimuli were administered at an individually-set temperature threshold for each subject.
In patients with borderline personality disorder, they found evidence of heightened activation of limbic circuitry in response to pictures evocative of positive and negative emotions, consistent with their reported emotion regulation problems. Amygdala activation also correlated with self-reported deficits in emotion regulation. However, the thermal stimuli inhibited the activation of the amygdala in these patients and also in healthy controls, presumably suppressing emotional reactivity.
Dr. John Krystal, Editor of Biological Psychiatry, commented, "These data are consistent with the hypothesis that physically painful stimuli provide some relief from emotional distress for some patients with borderline personality disorder because they paradoxically inhibit brain regions involved in emotion. This process may help them to compensate for deficient emotional regulation mechanisms."
The authors note that these results are in line with previous findings on emotional hyperactivity in borderline personality disorder and suggest that these individuals process pain stimuli differently depending on their arousal status.
Affect Regulation and Pain in Borderline Personality Disorder: A Possible Link to the Understanding of Self-Injury.
Inga Niedtfeld, Lars Schulze, Peter Kirsch, Sabine C. Herpertz, Martin Bohus, Christian Schmahl.
Biological Psychiatry, 2010; 68 (4): 383 - 391 DOI: 10.1016/j.biopsych.2010.04.015
Link to Bio Psych abstract
Monday, August 30, 2010
Mika Ono for the Online Weekly of the Scripps Research Institute (Aug. 30, 2010)
After more than a decade of research, Scripps Research Institute scientists have pieced together the structure of a human adenovirus -- the largest complex ever determined at atomic resolution. The new findings about the virus, which causes respiratory, eye, and gastrointestinal infections, may lead to more effective gene therapy and to new anti-viral drugs.
The study was published in the journal Science on August 27, 2010.
"We learned a number of important things about the virus from the structure, including how its key contacts are involved in its assembly," said Scripps Research Professor Glen Nemerow, who, together with Scripps Research colleague Associate Professor Vijay Reddy, led the study. "That's very important if you want to reengineer the virus for gene therapy."
"Even though a number of viral structures have been solved by x-ray crystallography, this is the biggest to date," said Reddy. "The adenovirus is 150 megadaltons, which contains roughly 1 million amino acids -- twice as big as PRD1, previously the largest virus ever solved to atomic resolution."
Crystal Structure of Human Adenovirus at 3.5 Å Resolution.
Vijay S. Reddy, S. Kundhavai Natchiar, Phoebe L. Stewart, and Glen R. Nemerow.
Science, 27 August 2010: 1071-1075 DOI: 10.1126/science.1187292
Link to Science abstract