Stress significantly increases mortality following a secondary bacterial respiratory infection

Abstract

A variety of mechanisms contribute to the viral-bacterial synergy which results in fatal secondary bacterial respiratory infections. Epidemiological investigations have implicated physical and psychological stressors as factors contributing to the incidence and severity of respiratory infections and psychological stress alters host responses to experimental viral respiratory infections. The effect of stress on secondary bacterial respiratory infections has not, however, been investigated. A natural model of secondary bacterial respiratory infection in naive calves was used to determine if weaning and maternal separation (WMS) significantly altered mortality when compared to calves pre-adapted (PA) to this psychological stressor. Following weaning, calves were challenged with Mannheimia haemolytica four days after a primary bovine herpesvirus-1 (BHV-1) respiratory infection. Mortality doubled in WMS calves when compared to calves pre-adapted to weaning for two weeks prior to the viral respiratory infection. Similar results were observed in two independent experiments and fatal viral-bacterial synergy did not extend beyond the time of viral shedding. Virus shedding did not differ significantly between treatment groups but innate immune responses during viral infection, including IFN-γ secretion, the acute-phase inflammatory response, CD14 expression, and LPS-induced TNFα production, were significantly greater in WMS versus PA calves. These observations demonstrate that weaning and maternal separation at the time of a primary BHV-1 respiratory infection increased innate immune responses that correlated significantly with mortality following a secondary bacterial respiratory infection.

Mindfulness‐based cancer recovery and supportive‐expressive therapy maintain telomere length relative to controls in distressed breast cancer survivors

“…5 The earliest studies demonstrated associations between naturally occurring stressors and telomere biology in noncancer samples, in which stress was associated with shorter TL and lower telomerase activity. 15,16 Although stress plays a role in the etiology and progression of many diseases, [17][18][19] the role of stress in cancer remains suggestive. 20,21 Nonetheless, several biobehavioral pathways between psychosocial stress and mechanisms of cancer development have been indentified.…”

Characterisation of haematological profiles and whole blood relative gene expression levels in Holstein-Friesian and Jersey bull calves undergoing gradual weaning

“…Stress induced by abrupt weaning, maternal separation and transportation of suckled beef calves alters the immune response and increases susceptibility to fatal bovine respiratory disease (Hodgson et al, 2012). Our group has previously reported that abrupt weaning exerts an acute stress response in single-suckled beef calves, characterised by changes in the distribution of haematological cells (Lynch et al, 2010;O'Loughlin et al, 2011) and up-regulation in expression of genes involved in the pro-inflammatory response (O'Loughlin et al, 2011).…”

The Impact of Self-Reported Psychological Stress Levels on Changes to Peripheral Blood Immune Biomarkers in Recreational Marathon Runners during Training and Recovery

“…Psychological stress results in the enhanced production of corticosteroids and catecholamines [21] which are potent immunomodulators [22]. In animal models, high-stress environments have been associated with increased morbidity and mortality following bacterial and viral infection [23,24]. People experiencing stressful life events, such as marital problems or caring for a sick relative, have been shown to have altered immunity such as a lower antibody response to influenza vaccination [25] and reactivation of latent viral infections [26].…”