Michael Muehlenbein | Baylor University (original) (raw)

Papers by Michael Muehlenbein

Virology Journal, Mar 29, 2006

Cambridge University Press eBooks, Jul 29, 2010

Cambridge University Press eBooks, Aug 2, 2010

PLOS ONE, Mar 15, 2012

Nature-based tourism can generate important revenue to support conservation of biodiversity. Howe... more Nature-based tourism can generate important revenue to support conservation of biodiversity. However, constant exposure to tourists and subsequent chronic activation of stress responses can produce pathological effects, including impaired cognition, growth, reproduction, and immunity in the same animals we are interested in protecting. Utilizing fecal samples (N = 53) from 2 wild habituated orangutans (Pongo pygmaeus morio) (in addition to 26 fecal samples from 4 wild unhabituated orangutans) in the Lower Kinabatangan Wildlife Sanctuary of Sabah, Malaysian Borneo, we predicted that i) fecal glucocorticoid metabolite concentrations would be elevated on the day after tourist visitation (indicative of normal stress response to exposure to tourists on the previous day) compared to samples taken before or during tourist visitation in wild, habituated orangutans, and ii) that samples collected from habituated animals would have lower fecal glucocorticoid metabolites than unhabituated animals not used for tourism. Among the habituated animals used for tourism, fecal glucocorticoid metabolite levels were significantly elevated in samples collected the day after tourist visitation (indicative of elevated cortisol production on the previous day during tourist visitation). Fecal glucocorticoid metabolite levels were also lower in the habituated animals compared to their age-matched unhabituated counterparts. We conclude that the habituated animals used for this singular ecotourism project are not chronically stressed, unlike other species/populations with documented permanent alterations in stress responses. Animal temperament, species, the presence of coping/escape mechanisms, social confounders, and variation in amount of tourism may explain differences among previous experiments. Acute alterations in glucocorticoid measures in wildlife exposed to tourism must be interpreted conservatively. While permanently altered stress responses can be detrimental, preliminary results in these wild habituated orangutans suggest that low levels of predictable disturbance can likely result in low physiological impact on these animals.

American journal of biological anthropology, Apr 3, 2023

American Journal of Men's Health

Testosterone levels in men appear to be prognostic of a number of disease outcomes, including sev... more Testosterone levels in men appear to be prognostic of a number of disease outcomes, including severe COVID-19 disease. Testosterone levels naturally decline with age and are lower in individuals with a number of comorbidities and chronic conditions. Low testosterone may therefore be both a cause and a consequence of illness, including COVID-19 disease. The present project examines whether preexisting conditions for severe COVID-19 disease were themselves related to serum-free testosterone levels in men who had not been infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. A clinical risk score for severe COVID-19 disease was computed based on the results of previously published meta-analyses and cohort studies, and relationships between this score and testosterone levels were tested in 142 men ages 19 to 82 years. Greater burden of preexisting conditions for severe COVID-19 disease was related to lower testosterone levels among men younger than 40 yea...

Journal of American College Health

American Journal of Human Biology

Journal of Community Health

of asymptomatic individuals, were developing [1, 2]. The risk of viral transmission could not be ... more of asymptomatic individuals, were developing [1, 2]. The risk of viral transmission could not be calculated based only using the number of symptomatic cases, the number of PCR-positive cases, or the number of hospitalizations or deaths in a given time or location. Organized serological testing was needed [3, 4], particularly in different local and regional settings that varied by government-regulated business, school, and social lockdowns and reopenings. Safely relaxing social distancing measures and reopening businesses and schools depended on the calculation of risk of transmission in various local populations. In Texas, USA, a shelter-in-place order began on March 13, 2020, with non-essential businesses reopening on May 1, 18, and 22, followed by other relaxations of safety measures. Variation in local public health requirements throughout the world precluded the accurate use of advanced epidemiological models based on the mixing of populations

The International Encyclopedia of Biological Anthropology

Journal of Public Health Research

Background: Pandemic fatigue describes a phenomenon whereby individuals experience a decrease in ... more Background: Pandemic fatigue describes a phenomenon whereby individuals experience a decrease in COVID-19 concern over time, despite their risk for infection remaining stable, or even increasing. Individual differences in the experience of pandemic fatigue may have important implications for people’s adherence to public health recommendations. Design and methods: Using data collected from a large community cohort in McLennan County, TX, longitudinal changes in COVID-19-related concern, stress, and affect across three appointments separated by approximately 4 weeks (July–November 2020) were examined. About 495, 349, and 286 participants completed one, two, and three appointments, respectively. Changes to stress physiology and local travel over time were also analyzed. Results: Results of a latent class growth analysis revealed four distinct classes of individuals: (a) low concern, low stress, (b) moderate concern, moderate stress, (c) moderate concern, low stress, and (d) high concer...

Adaptive Human Behavior and Physiology

Objective Though it injures the body in many ways, tattooing may also prepare it for later dermal... more Objective Though it injures the body in many ways, tattooing may also prepare it for later dermal stress through psychoneuroimmunological means. Methods To test this, we examined salivary endocrine (cortisol), immune (secretory immunoglobulin A), and inflammatory (C-reactive protein) responses to receiving a new tattoo relative to previous tattoo experience among 48 adults attending a tattoo festival. Results We found no effect of previous tattoo experience on pre-posttest cortisol but a significant main effect of extent of previous tattoo experience on pre-posttest cortisol and secretory immunoglobulin A and significant extent of body-by-hour tattooed interaction effect on C-reactive protein. Conclusions These findings suggest that the positive psychological evaluation of tattooing as eustress may contribute to biochemical adaptation through tattooing.

The International Encyclopedia of Primatology, 2017

American Journal of Primatology, 2021

Despite concern about environmental protection, travelers often underestimate the contribution th... more Despite concern about environmental protection, travelers often underestimate the contribution they may have to disease transmission to other species, as well as the risk of becoming infected themselves. Tourists in general tend to accept more physical risks when traveling than when at home, and much of this can be blamed on the temporary loss of situational awareness and loss of inhibition with a corresponding relaxed attitude toward safety. To better understand environmental attitudes and travel health knowledge and behaviors, a detailed survey of adult tourists was distributed on the island of St. Kitts, home to many green monkeys. Data from 1097 respondents were collected at two locations where cruise ship passengers typically visit the island. Results revealed that even though individuals with more positive environmental attitudes were more willing to take steps to mitigate tourism‐related disease transmission, they were also more likely to report wanting to touch or feed a mon...

Frontiers in Psychology, 2021

Risk perception and consequently engagement in behaviors to avoid illness often do not match actu... more Risk perception and consequently engagement in behaviors to avoid illness often do not match actual risk of infection, morbidity, and mortality. Unrealistic optimism occurs when individuals falsely believe that their personal outcomes will be more favorable than others' in the same risk category. Natural selection could favor overconfidence if its benefits, such as psychological resilience, outweigh its costs. However, just because optimism biases may have offered fitness advantages in our evolutionary past does not mean that they are always optimal. The current project examined relationships among personal risk for severe COVID-19, risk perceptions, and preventative behaviors. We predicted that those with higher risk of severe COVID-19 would exhibit unrealistic optimism and behave in ways inconsistent with their elevated risk of morbidity and mortality. Clinical risk scores for severe COVID-19 were calculated and compared with COVID-19 threat appraisal, compliance with shelter-...

Disaster Medicine and Public Health Preparedness, 2021

Colleges and universities around the world engaged diverse strategies during the COVID-19 pandemi... more Colleges and universities around the world engaged diverse strategies during the COVID-19 pandemic. Baylor University, a community of ˜22,700 individuals, was 1 of the institutions which resumed and sustained operations. The key strategy was establishment of multidisciplinary teams to develop mitigation strategies and priority areas for action. This population-based team approach along with implementation of a “Swiss Cheese” risk mitigation model allowed small clusters to be rapidly addressed through testing, surveillance, tracing, isolation, and quarantine. These efforts were supported by health protocols including face coverings, social distancing, and compliance monitoring. As a result, activities were sustained from August 1 to December 8, 2020. There were 62,970 COVID-19 tests conducted with 1435 people testing positive for a positivity rate of 2.28%. A total of 1670 COVID-19 cases were identified with 235 self-reports. The mean number of tests per week was 3500 with approximat...

Journal of Travel Medicine, 2020

BackgroundHuman coexistence with other animals can result in both intentional and unintentional c... more BackgroundHuman coexistence with other animals can result in both intentional and unintentional contact with a variety of mammalian and non-mammalian species. International travellers are at risk for such encounters; travellers risk injury, infection and possibly death from domestic and wild animal bites, scratches, licks and other exposures. The aim of the present analysis was to understand the diversity and distribution of animal-related exposures among international travellers.MethodsData from January 2007 through December 2018 from the GeoSentinel Surveillance Network were reviewed. Records were included if the exposure was non-migration travel with a diagnosis of an animal (dog, cat, monkey, snake or other) bite or other exposure (non-bite); records were excluded if the region of exposure was not ascertainable or if another, unrelated acute diagnosis was reported.ResultsA total of 6470 animal exposures (bite or non-bite) were included. The majority (71%) occurred in Asia. Trave...