Young F.,University of British Columbia |
Marra F.,University of British Columbia |
Marra F.,Center for Disease Control
Vaccine | Year: 2011
Influenza infection is associated with many complications, which can lead to hospitalizations and death. This is particularly true for the older adults who are not able to mount as good an immune response as younger adults due to their declining immune function. As such, different strategies are being evaluated to increase immunogenicity in the older adults, including use of adjuvanted vaccines and different delivery techniques, which can enhance immunogenicity as well as potentially be dose-sparing. The objective of this paper was to conduct a systematic review of studies that evaluated the efficacy (in terms of immunogenicity) and safety of intradermal (ID) influenza vaccines compared with traditional methods of administration in the general population and the older adults. Thirteen randomized, controlled, open-label trials were included in this systematic review. Seven trials were conducted in young adults 18-60 years of age, 4 trials were studied in older subjects >60 years, and 2 trials included both young and older adults, of which one did separate analyses for both groups and one did a separate analysis for the older adult population only. We found 7 studies out of 8 for the 18-60-year olds and 4 out of 6 studies in the over 60-year olds showed comparable efficacy between ID and intramuscular (IM) administration. Two out of 6 studies in the over 60-year olds showed superiority of ID administration over IM. Rates of adverse events occurring in the first 3 days were comparable between ID and IM administration of influenza vaccines; however, when assessing adverse events occurring in the first 7 days, rates of local adverse events were consistently higher in the ID group, specifically erythema, swelling, induration, and pruritis. In conclusion, our review shows comparable efficacy between ID and IM administration of influenza vaccine in both the younger and older adults. © 2011 Elsevier Ltd.
Hottes T.S.,Center for Disease Control
Journal of medical Internet research | Year: 2012
The feasibility and acceptability of Internet-based sexually transmitted infection (STI) testing have been demonstrated; however, few programs have included testing for human immunodeficiency virus (HIV). In British Columbia, Canada, a new initiative will offer online access to chlamydia, gonorrhea, syphilis, and HIV testing, integrated with existing clinic-based services. We presented the model to gay men and other men who have sex with men (MSM) and existing clinic clients through a series of focus groups. To identify perceived benefits, concerns, and expectations of a new model for Internet-based STI and HIV testing among potential end users. Participants were recruited through email invitations, online classifieds, and flyers in STI clinics. A structured interview guide was used. Focus groups were audio recorded, and an observer took detailed field notes. Analysts then listened to audio recordings to validate field notes. Data were coded and analyzed using a scissor-and-sort technique. In total, 39 people participated in six focus groups. Most were MSM, and all were active Internet users and experienced with STI/HIV testing. Perceived benefits of Internet-based STI testing included anonymity, convenience, and client-centered control. Salient concerns were reluctance to provide personal information online, distrust of security of data provided online, and the need for comprehensive pretest information and support for those receiving positive results, particularly for HIV. Suggestions emerged for mitigation of these concerns: provide up-front and detailed information about the model, ask only the minimal information required for testing, give positive results only by phone or in person, and ensure that those testing positive are referred for counseling and support. End users expected Internet testing to offer continuous online service delivery, from booking appointments, to transmitting information to the laboratory, to getting prescriptions. Most participants said they would use the service or recommend it to others. Those who indicated they would be unlikely to use it generally either lived near an STI clinic or routinely saw a family doctor with whom they were comfortable testing. Participants expected that the service would provide the greatest benefit to individuals who do not already have access to sensitive sexual health services, are reluctant to test due to stigma, or want to take immediate action (eg, because of a recent potential STI/HIV exposure). Internet-based STI/HIV testing has the potential to reduce barriers to testing, as a complement to existing clinic-based services. Trust in the new online service, however, is a prerequisite to client uptake and may be engendered by transparency of information about the model, and by accounting for concerns related to confidentiality, data usage, and provision of positive (especially HIV) results. Ongoing evaluation of this new model will be essential to its success and to the confidence of its users.
Wang R.,University of British Columbia |
Henderson S.B.,University of British Columbia |
Henderson S.B.,Center for Disease Control |
Sbihi H.,University of British Columbia |
And 2 more authors.
Atmospheric Environment | Year: 2013
Background: Land-use regression (LUR) is a cost-effective approach for predicting spatial variability in ambient air pollutant concentrations with high resolution. Models have been widely used in epidemiological studies and are often applied to time periods before or after the period of air quality monitoring used in model development. However, it is unclear how well such models perform when extrapolated over time. Objective: The objective of this study was to assess the temporal stability of LUR models over a period of 7 years in Metro Vancouver, Canada. Methods: A set of NO and NO2 LUR models based on 116 measurements were developed in 2003. In 2010, we made 116 measurements again, of which 73 were made at the exact same location as in 2003. We then developed 2010 models using updated data for the same predictor variables used in 2003, and also explored additional variables. Four methods were used to derive model predictions over 7 years, and predictions were compared with measurements to assess the temporal stability of LUR models. Results: The correlation between 2003 NO and 2010 NO measurements was 0.87 with a mean (sd) decrease of 11.3 (9.9) ppb. For NO2, the correlation was 0.74, with a mean (sd) decrease of 2.4 (3.2) ppb. 2003 and 2010 LUR models explained similar amounts of spatial variation (R2 = 0.59 and R2 = 0.58 for NO; R2 = 0.52 and R2 = 0.63 for NO2, in 2003 and in 2010 respectively). The 2003 models explained more variability in the 2010 measurements (R2 = 0.58-0.60 for NO; R2 = 0.52-0.61 for NO2) than the 2010 models explained in the 2003 measurements (R2 = 0.50-0.55 for NO; R2 = 0.44-0.49 for NO2), and the 2003 models explained as much variability in the 2010 measurements as they did in the 2003 measurements. Conclusion: LUR models are able to provide reliable estimates over a period of 7 years in Metro Vancouver. When concentrations and their variability are decreasing over time, the predictive power of LUR models is likely to remain the same or to improve in forecasting scenarios, but to decrease in hind-casting scenarios. © 2012 Elsevier Ltd.
Taylor D.,Center for Disease Control
Systematic reviews | Year: 2013
Three meta-analyses and one systematic review have been conducted on the question of whether self-collected specimens are as accurate as clinician-collected specimens for STI screening. However, these reviews predate 2007 and did not analyze rectal or pharyngeal collection sites. Currently, there is no consensus on which sampling method is the most effective for the diagnosis of genital chlamydia (CT), gonorrhea (GC) or human papillomavirus (HPV) infection. Our meta-analysis aims to be comprehensive in that it will examine the evidence of whether self-collected vaginal, urine, pharyngeal and rectal specimens provide as accurate a clinical diagnosis as clinician-collected samples (reference standard). Eligible studies include both randomized and non-randomized controlled trials, pre- and post-test designs, and controlled observational studies. The databases that will be searched include the Cochrane Database of Systematic Reviews, Web of Science, Database of Abstracts of Reviews of Effects (DARE), EMBASE and PubMed/Medline. Data will be abstracted independently by two reviewers using a standardized pre-tested data abstraction form. Heterogeneity will be assessed using the Q2 test. Sensitivity and specificity estimates with 95% confidence intervals as well as negative and positive likelihood ratios will be pooled and weighted using random effects meta-analysis, if appropriate. A hierarchical summary receiver operating characteristics curve for self-collected specimens will be generated. This synthesis involves a meta-analysis of self-collected samples (urine, vaginal, pharyngeal and rectal swabs) versus clinician-collected samples for the diagnosis of CT, GC and HPV, the most prevalent STIs. Our systematic review will allow patients, clinicians and researchers to determine the diagnostic accuracy of specimens collected by patients compared to those collected by clinicians in the detection of chlamydia, gonorrhea and HPV.
News Article | August 23, 2016
This December, the signatory nations of the will meet, as they do every five years, to discuss the state of bioweapons globally. In at least one way, the world has radically changed since they last met, in 2011. The discovery of several novel gene-editing techniques, most famous being CRISPR-Cas9, might be the scientific breakthrough of this century. It has unleashed a torrent of studies that aim to cure everything from cancer to world hunger. But this new era of synthetic biology has a dark side. Scientific discoveries generally outpace our ability to legislate sensible limits, or even understand exactly what we’re playing with; that’s the point of experimental research, after all: to chart the unknown. The discovery last year that scientists in China have begun using gene-editing techniques on human embryos —a troubling, unprecedented step towards a sci-fi dystopia —has ignited a vigorous global debate about the limits we ought to have when manipulating biology. The advent of CRISPR has corresponded with a widespread democratization of biology. Gene-editing kits are cheap, legal, and relatively easy to use . have proliferated throughout the world, teaching amateurs how to perform elementary gene-editing themselves. This approach, too, holds much promise; after all, some of this nation’s most celebrated scientific achievements were discovered by tinkering amateurs in the garage. For a few hundred dollars you can experiment with genome editing at your kitchen table. The monopoly on biology once held by governments and universities has been broken. Only a few years ago, the production of a bioweapon took the resources and expertise of a nation-state. Now a few dedicated terrorists could, theoretically, manipulate lethal pathogens in a DIY lab built with cheap equipment bought legally online, making the disease more potent and resistant to antidotes or vaccines. History abounds with examples of the terrifying potential of bioweapons. Bubonic plague-infected bodies were dumped in enemy wells in the Middle Ages, or catapulted over enemy walls during siege. Blankets infected with smallpox were given to Native Americans by British Colonialists, with devastating results. Most extreme were the . During WWII, Japan dropped ceramic “bombs” filled with bubonic plague-infected fleas over Chinese cities, which killed hundreds of thousands of civilians, including nearly 20% of the airmen who unleashed the pestilence. The US conducted its own offensive biowarfare research from 1942 until 1969, at the , at Fort Detrick, Maryland. It was there that the military learned how to weaponize lethal pathogens like anthrax and botulinum toxin, and how to produce them on an industrial scale. Fort Detrick in the 1940's doesn't seem all that welcoming. They also learned how such weapons might be deployed. In September 1950, , unbeknownst to the public until the details were leaked to the press, years later. According to statements given during a congressional investigation, Navy vessels pulled up in the bay at night, spraying a benign—or so they thought—bacteria called Serratia marcescens from hoses on the decks. The aerosol drifted downwind over the city, into the lungs of its 800,000 residents. (11 of those citizens checked into one local hospital in the proceeding days with pneumonia caused by what doctors suspected to be Serratia marcescens. One of them died. The doctors, unaware that a military experiment was underway, considered it a mystery.) It was one of 239 open-air tests of biological agents on the American public by the military between the ‘40s and ‘60s. 80 of those tests used live bacteria. By 1969, when Nixon ended offensive bioweapons research, the U.S. had amassed not only a formidable arsenal of pathogens, but they had also pioneered methods for how to deploy them. Though grossly unethical and unsettling—straight out of X-Files, really—those experiments on our cities were valuable. They demonstrated that lethal doses of pathogens and toxins, released in aerosol form, could travel more than 10 miles from the release point. The U.S. military knew for sure that a bioterrorism could work because they tried it themselves. But one of the ugly, inescapable facts of military technology is that there’s no way of inventing an instrument of death without other people getting ahold of it. It always gets out. The Biological Weapons Convention treaty, which went into effect in 1975, was a formal recognition by the international community that some things have such horrible potential they just ought not be invented at all. It was supposed to end the chapter of biological warfare, outlawing nations from developing, acquiring, stockpiling or retaining certain pathogens, except for limited samples for defensive vaccine and antidote research. But, as with most international treaties, the BWC was rather toothless. There’s no way to verify that nations are abiding, or to what extent. It’s now known that the USSR continued its offensive bioweapons program for years after signing the pact . Even now, Russia, China and Syria are suspected of continuing such work under the auspices of defensive research. The U.S. biodefense sector has also been accused of breaching the treaty. The turning point was the 2001 anthrax attacks, in which letters filled with the spore-forming bacteria were mailed to several Senators. Anthrax isn’t new—it has been used as a weapon since WWI—but, coming within weeks of 9/11, the attacks created a panic, and newfound urgency to confront the threat of bioweapons. It led to the creation of the , a unit within the Department of Homeland Security. NBACC in particular has been accused of crossing the line into offensive research, thus violating the principles of the BWC. In a way, they’re in an impossible situation. Having vowed not to stockpile or develop deadly pathogens, they must still conduct aggressive research to stay ahead of emerging threats that no one quite understands yet. And with China playing loose with bioethics by experimenting on humans, and terrorist groups who are pleased to watch the world burn, we’re competing with rivals who will accept what we won’t. U.S. researchers are left with no choice but to carry on innovating with pathogens: improving our—and, since things always get out, the world’s—understanding of how they work, how they can be diagnosed and treated, and how they could be improved. Essentially, drafting the blueprint for the bioweapons we fear will someday be invented, hereby inventing them. To dream of it is to make it so. In 2014, on what’s known as “gain-of-function” studies on viruses like SARS, influenza and MERS. There were concerns that a well-intentioned scientist in search of a cure might create an even deadlier version of a disease using gene-editing techniques, which would then, inevitably, proliferate when they published the results, introducing yet another menace to the world. The moratorium was intended to give the government a chance to draft some regulations to review these studies. The Center for Disease Control, Atlanta, which you may remember from the Walking Dead... It came after a series of high-profile slip-ups by the Center for Disease Control, in Atlanta , which houses the national stockpile of vaccines, it addition to live samples of every biological hazard known to mankind. That year, technicians there accidentally shipped a live sample of H5N1, a particularly virulent and deadly form of avian flu, to researchers as the Department of Agriculture who had requested, and were expecting, a more benign version of the disease. This came weeks after CDC technicians nearly poisoned themselves by experimenting with anthrax samples they didn’t know was live. The potential for gene-editing techniques to engineer biological weapons of unprecedented power—coupled with the familiar shape-shifting ingenuity of nature itself, in which baleful bacteria and viruses mutate with such speed and vigor we just can’t seem to figure them out—will pose a significant challenge to the values and ethics captured in the BWC treaty. There was a reason we, as a global community, decided to close the book on biowarfare: You can’t un-invent a lethal weapon. But is it even possible to be exclusively defensive when confronting death by biology? Made possible by Deus Ex: Mankind Divided. In stores August 23rd.