scholarly journals The porcine respiratory microbiome: recent insights and future challenges

2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Mattia Pirolo ◽  
Carmen Espinosa-Gongora ◽  
Debby Bogaert ◽  
Luca Guardabassi

AbstractUnderstanding the structure of the respiratory microbiome and its complex interactions with opportunistic pathogenic bacteria has become a topic of great scientific and economic interest in livestock production, given the severe consequences of respiratory disease on animal health and welfare. The present review focuses on the microbial structures of the porcine upper and lower airways, and the factors that influence microbiome development and onset of respiratory disease. Following a literature search on PubMed and Scopus, 21 articles were selected based on defined exclusion criteria (20 studies performed by 16S rRNA gene sequencing and one by shotgun metagenomics). Analysis of the selected literature indicated that the microbial structure of the upper respiratory tract undergoes a remarkable evolution after birth and tends to stabilise around weaning. Antimicrobial treatment, gaseous ammonia concentration, diet and floor type are amongst the recognized environmental factors influencing microbiome structure. The predominant phyla of the upper respiratory tract are Proteobacteria and Firmicutes with significant differences at the genus level between the nasal and the oropharyngeal cavity. Only five studies investigated the lower respiratory tract and their results diverged in relation to the relative abundance of these two phyla and even more in the composition of the lung microbiome at the genus level, likely because of methodological differences. Reduced diversity and imbalanced microbial composition are associated with an increased risk of respiratory disease. However, most studies presented methodological pitfalls concerning specimen collection, sequencing target and depth, and lack of quality control. Standardization of sampling and sequencing procedures would contribute to a better understanding of the structure of the microbiota inhabiting the lower respiratory tract and its relationship with pig health and disease.

2017 ◽  
Vol 100 (2) ◽  
pp. 1445-1458 ◽  
Author(s):  
Natália C. Gaeta ◽  
Svetlana F. Lima ◽  
Andre G. Teixeira ◽  
Erika K. Ganda ◽  
Georgios Oikonomou ◽  
...  

Author(s):  
Caoimhe Tiernan ◽  
Thomas Comyns ◽  
Mark Lyons ◽  
Alan M Nevill ◽  
Giles Warrington

This study aimed to investigate the association between training load indices and Upper Respiratory Tract Infection (URTI) across different lag periods in elite soccer players. Internal training load was collected from 15 elite soccer players over one full season (40 weeks). Acute, chronic, Acute:Chronic Workload Ratio (ACWR), Exponentially Weighted Moving Averages (EWMA) ACWR, 2, 3 and 4-week cumulative load, training strain and training monotony were calculated on a rolling weekly basis. Players completed a daily illness log, documenting any signs and symptoms, to help determine an URTI. Multilevel logistic regression was used to analyze the associations between training load indices and URTIs across different lag periods (1 to 7-days). The results found a significant association between 2-week cumulative load and an increased likelihood of a player contracting an URTI 3 days later (Odds Ratio, 95% Confidence Interval: OR = 2.07, 95% CI = 0.026-1.431). Additionally, a significant association was found between 3-week cumulative load and a players’ increased risk of contracting an URTI 4 days later (OR = 1.66, 95% CI = 0.013–1.006). These results indicate that accumulated periods of high training load (2- and 3-week) associated with an increased risk of a player contracting an URTI, which may lead to performance decrements, missed training sessions or even competitions.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Cheng Lei ◽  
Lisong Yang ◽  
Cheong Tat Lou ◽  
Fan Yang ◽  
Kin Ian SiTou ◽  
...  

Abstract Background Acute respiratory infections (ARIs) are among the leading causes of hospitalization in children. Understanding the local dominant viral etiologies is important to inform infection control practices and clinical management. This study aimed to investigate the viral etiology and epidemiology of respiratory infections among pediatric inpatients in Macao. Methods A retrospective study using electronic health records between 2014 and 2017 at Kiang Wu Hospital was performed. Nasopharyngeal swab specimens were obtained from hospitalized children aged 13 years or younger with respiratory tract diseases. xMAP multiplex assays were employed to detect respiratory agents including 10 respiratory viruses. Data were analyzed to describe the frequency and seasonality. Results Of the 4880 children enrolled in the study, 3767 (77.1%) were positive for at least one of the 13 viral pathogens tested, of which 2707 (55.5%) being male and 2635 (70.0%) under 2 years old. Among the positive results, there were 3091 (82.0%) single infections and 676 (18.0%) multiple infections. The predominant viruses included human rhinovirus/enterovirus (HRV/EV 27.4%), adenovirus (ADV, 15.8%), respiratory syncytial virus B (RSVB, 7.8%) and respiratory syncytial virus A (RSVA, 7.8%). The detection of viral infection was the most prevalent in autumn (960/1176, 81.6%), followed by spring (1095/1406, 77.9%), winter (768/992, 77.4%), and summer (944/1306, 72.3%), with HRV/EV and ADV being most commonly detected throughout the 4 years of study period. The detection rate of viral infection was highest among ARI patients presented with croup (123/141, 87.2%), followed by lower respiratory tract infection (1924/2356, 81.7%) and upper respiratory tract infection (1720/2383, 72.2%). FluA, FluB and ADV were positive factors for upper respiratory tract infections. On the other hand, infection with RSVA, RSVB, PIV3, PIV4, HMPV, and EV/RHV were positively associated with lower respiratory tract infections; and PIV1, PIV2, and PIV3 were positively associated with croup. Conclusions This is the first study in Macao to determine the viral etiology and epidemiology of pediatric patients hospitalized for ARIs. The study findings can contribute to the awareness of pathogen, appropriate preventative measure, accurate diagnosis, and proper clinical management of respiratory viral infections among children in Macao.


1920 ◽  
Vol 32 (6) ◽  
pp. 719-744 ◽  
Author(s):  
Russell L. Cecil ◽  
Francis G. Blake

1. Virulent influenza bacilli, when injected into the nose and throat of monkeys (Cebus capucinus and Macacus syrichtus), excite an acute inflammation of the upper respiratory tract, characterized by swelling and hyperemia of the mucous membrane, infiltration of the mucosa and subrnucosa with leucocytes, desquamation of epithelial cells, and the production of a mucopurulent exudate. The accessory sinuses are often implicated in the infection. 2. Experimental Bacillus influenzæ infections of the upper respiratory tract are frequently accompanied or followed by bronchiolitis, peribronchial infiltration, and bronchopneumonia with hemorrhage and edema in the early stage, emphysema and bronchiectasis in the later stages. In general, the process closely resembles uncomplicated Bacillus influenzæ pneumonia in man. 3. The injection of virulent influenza bacilli directly into the trachea of monkeys induces in them an experimental bronchiolitis and hemorrhagic bronchopneumonia, similar in all respects to spontaneous Bacillus influenzæ pneumonia. 4. In experimental Bacillus influenzæinfections of either the upper or lower respiratory tract the influenza bacillus can usually be recovered during .the acute stage by culture, either pure or in association with other bacteria. 5. In experimental Bacillus influenzæ infections in monkeys characteristic changes occur in the thymus gland—hyperplasia of the follicles, distention of the lymphatic channels, and infiltration of the parenchyma with leucocytes. This enlargement appears to be merely part of a general hyperplasia of the lymphoid structures in the cervical and thoracic regions.


2002 ◽  
Vol 70 (2) ◽  
pp. 481-490 ◽  
Author(s):  
Susan L. Brockmeier ◽  
Karen B. Register ◽  
Tibor Magyar ◽  
Alistair J. Lax ◽  
Gillian D. Pullinger ◽  
...  

ABSTRACT Bordetella bronchiseptica is one of the etiologic agents causing atrophic rhinitis and pneumonia in swine. It produces several purported virulence factors, including the dermonecrotic toxin (DNT), which has been implicated in the turbinate atrophy seen in cases of atrophic rhinitis. The purpose of these experiments was to clarify the role of this toxin in respiratory disease by comparing the pathogenicity in swine of two isogenic dnt mutants to their virulent DNT+ parent strains. Two separate experiments were performed, one with each of the mutant-parent pairs. One-week-old cesarean-derived, colostrum-deprived pigs were inoculated intranasally with the parent strain, the dnt mutant strain, or phosphate-buffered saline. Weekly nasal washes were performed to monitor colonization of the nasal cavity, and the pigs were euthanized 4 weeks after inoculation to determine colonization of tissues and to examine the respiratory tract for pathology. There was evidence that colonization of the upper respiratory tract, but not the lower respiratory tract, was slightly greater for the parent strains than for the dnt mutants. Moderate turbinate atrophy and bronchopneumonia were found in most pigs given the parent strains, while there was no turbinate atrophy or pneumonia in pigs challenged with the dnt mutant strains. Therefore, production of DNT by B. bronchiseptica is necessary to produce the lesions of turbinate atrophy and bronchopneumonia in pigs infected with this organism.


PEDIATRICS ◽  
1969 ◽  
Vol 43 (5) ◽  
pp. 799-808
Author(s):  
Jack Wolfsdorf ◽  
David L. Swift ◽  
Mary Ellen Avery

Aerosol deposition in the upper and lower respiratory tract using technetium-labelled water aerosol, produced by jet and ultrasonic nebulizers, with and without 10% propylene glycol, was examined under conditions of nasal, normal mouth, and tube breathing in 15 normal adults. With nasal breathing, 91.5% (± 5.5) and 83.2% (± 6.3) of the mass of the aerosol produced by the jet and ultrasonic nebulizers, respectively, was deposited in the upper respiratory tract. Similar fractional depositions were observed with the addition of 10% propylene glycol. When breathing was carried out via a mouth tube, 43% to 59% of the mass of the aerosol produced by the nebulizers was deposited in the upper respiratory tract. The mass median diameters of the available aerosols produced by the jet and ultrasonic nebulizers were 6.0 µ (geometric standard deviation = 2.5) and 2.8 µ (geometric standard deviation = 2.1), respectively; the densities of the aerosols produced were 8 and 34 µl/liter air. With nasal or normal mouth breathing, the volume of water, in aerosol form, that could be deposited per 24 hours in the lower respiratory tract of an adult was calculated to be about 6 ml and 49 ml for the jet and ultrasonic nebulizer, respectively.


1998 ◽  
Vol 76 (5) ◽  
pp. 573-580 ◽  
Author(s):  
David C Nieman

Epidemiological data suggest that endurance athletes are at increased risk for upper respiratory tract infection (URTI) during periods of heavy training and the 1- to 2-week period following race events. Moderate exercise training has been associated with a reduction in incidence of URTI. There is growing evidence that for several hours subsequent to heavy exertion, several components of both the innate (e.g., natural killer cell activity and neutrophil oxidative burst activity) and adaptive (e.g., T and B cell function) immune system exhibit suppressed function. The immune response to heavy exertion is transient, and further research on the mechanisms underlying the immune response to prolonged and intensive endurance exercise is necessary before meaningful clinical applications can be drawn. Some attempts have been made through chemical or nutritional means (e.g., indomethacin, glutamine, vitamin C, and carbohydrate supplementation) to attenuate immune changes following intensive exercise to lower the risk of infection.Key words: upper respiratory tract infection, immunity, running, lymphocyte, neutrophil.


2011 ◽  
Vol 108 (7) ◽  
pp. 1235-1245 ◽  
Author(s):  
Denise C. Hunter ◽  
Margot A. Skinner ◽  
Frances M. Wolber ◽  
Chris L. Booth ◽  
Jacelyn M. S. Loh ◽  
...  

In the elderly, immunosenescence and malnourishment can contribute to increased risk and severity of upper respiratory tract infections (URTI). Gold kiwifruit (Actinidia chinensis ‘Hort16A’) contains nutrients important for immune function and mitigation of symptoms of infection, including vitamins C and E, folate, polyphenols and carotenoids. The objective of the present study was to evaluate whether regular consumption of gold kiwifruit reduces symptoms of URTI in older people, and determine the effect it has on plasma antioxidants, and markers of oxidative stress, inflammation and immune function. A total of thirty-two community-dwelling people ( ≥ 65 years) participated in a randomised crossover study, consuming the equivalent of four kiwifruit or two bananas daily for 4 weeks, with treatments separated by a 4-week washout period. Participants completed the Wisconsin Upper Respiratory Symptom Survey-21 daily, and blood samples were collected at baseline and at the end of each treatment and washout period. Gold kiwifruit did not significantly reduce the overall incidence of URTI compared with banana, but significantly reduced the severity and duration of head congestion, and the duration of sore throat. Gold kiwifruit significantly increased plasma vitamin C, α-tocopherol and lutein/zeaxanthin concentrations, and erythrocyte folate concentrations, and significantly reduced plasma lipid peroxidation. No changes to innate immune function (natural killer cell activity, phagocytosis) or inflammation markers (high-sensitivity C-reactive protein, homocysteine) were detected. Consumption of gold kiwifruit enhanced the concentrations of several dietary plasma analytes, which may contribute to reduced duration and severity of selected URTI symptoms, offering a novel tool for reducing the burden of URTI in older individuals.


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