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Michael A Stoto

Publications and source records attributed to Michael A Stoto.

7 recordsLinked to original sources

Transmission patterns of smallpox: systematic review of natural outbreaks in Europe and North America since World War II.

BACKGROUND: Because smallpox (variola major) may be used as a biological weapon, we reviewed outbreaks in post-World War II Europe and North America in order to understand smallpox transmission patterns. METHODS: A systematic review was used to identify papers from the National Library of Medicine, Embase, Biosis, Cochrane Library, Defense Technical Information Center, WorldCat, and reference lists of included publications. Two authors reviewed selected papers for smallpox outbreaks. RESULTS: 51 relevant outbreaks were identified from 1,389 publications. The median for the effective first generation reproduction rate (initial R) was 2 (range 0-38). The majority outbreaks were small (less than 5 cases) and contained within one generation. Outbreaks with few hospitalized patients had low initial R values (median of 1) and were prolonged if not initially recognized (median of 3 generations); outbreaks with mostly hospitalized patients had higher initial R values (median 12) and were shorter (median of 3 generations). Index cases with an atypical presentation of smallpox were less likely to have been diagnosed with smallpox; outbreaks in which the index case was not correctly diagnosed were larger (median of 27.5 cases) and longer (median of 3 generations) compared to outbreaks in which the index case was correctly diagnosed (median of 3 cases and 1 generation). CONCLUSION: Patterns of spread during Smallpox outbreaks varied with circumstances, but early detection and implementation of control measures is a most important influence on the magnitude of outbreaks. The majority of outbreaks studied in Europe and North America were controlled within a few generations if detected early.

Communicable Disease Control↗

The precautionary principle and emerging biologic risks: lessons from human immunodeficiency virus in blood products.

In times of crisis, such as during the early 1980s when acquired immune deficiency syndrome (AIDS) was first recognized as a threat to the blood supply, it can be difficult to find reliable evidence upon which to base appropriate public health policies. Unreliable evidence produces substantial scientific uncertainty. Yet despite ambiguity and unanswered questions, decisions must be made and policy established to protect people's health. The precautionary principle provides important guidelines for public health policy decision making that are of particular value in times of crisis, such as the emergence of a new pathogen: be open and honest about scientific uncertainty; communicate with the public; and consider immediate, adaptable policy decisions. Ongoing research into the important uncertainties and review of policies in light of the data that emerge are crucial to the development of good public policy.

Blood Banks↗

Searching one or two databases was insufficient for meta-analysis of observational studies.

OBJECTIVE: To address methodologic issues in searching for observational studies by presenting database search methods and results. STUDY DESIGN AND SETTING: Results of two literature searches for publications reporting on observational studies of alcohol consumption and the risk of breast cancer and large bowel cancer were compared, to evaluate the sensitivity of various bibliographic databases and search strategies, including hand-searching reviews and meta-analyses. RESULTS: The target sensitivity of 90% of publications in the breast cancer search was achieved by starting with Medline, then adding Biosis, Embase, and SCI EXPANDED-SSCI, which provided a total of 72 (91%) of the 79 relevant publications. To reach a similar 89% sensitivity for large bowel cancer, at least Biosis, Dissertation Abstracts Online, Embase, ETOH, and Medline had to be searched, with the addition of hand search of reviews and meta-analyses. CONCLUSION: Limiting a search to one or two databases when conducting meta-analyses of observational studies will not provide a thorough summary of the existing literature. The findings support recommendations to implement a comprehensive search of electronic databases and the reference lists of recent review articles and meta-analyses.

Alcohol Drinking↗

American College of Epidemiology Ethics Guidelines: foundations and dissemination.

Epidemiology is a core science of public health, focusing on research related to the distribution and determinants of both positive and adverse health states and events and on application of knowledge gained to improve public health. The American College of Epidemiology (ACE) is a professional organization devoted to the professional practice of epidemiology. As part of that commitment, and in response to concerns for more explicit attention to core values and duties of epidemiologists in light of emerging issues and increased scrutiny of epidemiology, the College developed, adopted, and published a set of Ethics Guidelines. The structure of the ACE ethics guidelines is in four parts: (1) a brief statement of core values and duties of epidemiologists, coupled with the virtues important to professional practice; (2) concise statements of key duties and obligations; (3) exposition of the duties and obligations with more applications; and (4) a brief summary and conclusion. The Guidelines have been published on the ACE website and in the official College journal Annals of Epidemiology. The guidelines contain (and maintain) core elements that define the discipline of epidemiology and its fundamental duties, but they are also intended to be dynamic and evolving, responsive to a changing professional and social environment.

Codes of Ethics↗

A model for a smallpox-vaccination policy.

BACKGROUND: The new reality of biologic terrorism and warfare has ignited a debate about whether to reintroduce smallpox vaccination. METHODS: We developed scenarios of smallpox attacks and built a stochastic model of outcomes under various control policies. We conducted a systematic literature review and estimated model parameters on the basis of European and North American outbreaks since World War II. We assessed the trade-offs between vaccine-related harms and benefits. RESULTS: Nations or terrorists possessing a smallpox weapon could feasibly mount attacks that vary with respect to tactical complexity and target size, and patterns of spread can be expected to vary according to whether index patients are hospitalized early. For acceptable results, vaccination of contacts must be accompanied by effective isolation. Vaccination of contacts plus isolation is expected to result in 7 deaths (from vaccine or smallpox) in a scenario involving the release of variola virus from a laboratory, 19 deaths in a human-vector scenario, 300 deaths in a building-attack scenario, 2735 deaths in a scenario involving a low-impact airport attack, and 54,729 deaths in a scenario involving a high-impact airport attack. Immediate vaccination of the public in an attacked region would provide little additional benefit. Prior vaccination of health care workers, who would be disproportionately affected, would save lives in large local or national attacks but would cause 25 deaths nationally. Prior vaccination of health care workers and the public would save lives in a national attack but would cause 482 deaths nationally. The expected net benefits of vaccination depend on the assessed probability of an attack. Prior vaccination of health care workers would be expected to save lives if the probability of a building attack exceeded 0.22 or if the probability of a high-impact airport attack exceeded 0.002. The probability would have to be much higher to make vaccination of the public life-saving. CONCLUSIONS: The analysis favors prior vaccination of health care workers unless the likelihood of any attack is very low, but it favors vaccination of the public only if the likelihood of a national attack or of multiple attacks is high.

Bioterrorism↗

The precautionary principle and emerging biological risks: lessons from swine flu and HIV in blood products.

Two examples-the "swine flu affair" in 1976 and the emergence of HIV in the blood supply in the early 1980s-illustrate the difficulties of decision-making in public health. Both cases illustrate trade-offs between product risks and public health benefits, especially with regard to uncertainty in estimates of product risks, public health risks, and the benefits of prevention. The cases also illustrate the tendency of public health policy makers to go all the way or do nothing at all, rather than consider intermediate options that can be adapted as new information emerges. This review suggests three lessons for public health policy makers: (1) be open and honest about scientific uncertainty; (2) communicate with the public, even when the facts are not clear; and (3) consider intermediate, adaptable policy options, such as obtaining more information, thus reducing uncertainty, and building in decision points to reconsider initial policies. Underlying all of these lessons is the need to commission studies to resolve important uncertainties and increase the information base for public communication, and to review regulations and other policy options in the light of the new data that emerge.

Blood Banks↗