Epidemiological and etiological characteristics of 1266 patients with severe acute respiratory infection in central China, 2018-2020: a retrospective survey

BACKGROUND

Severe acute respiratory infection (SARI), a significant global health concern, imposes a substantial disease burden. In China, there is inadequate data concerning the monitoring of respiratory pathogens, particularly bacteria, among patients with SARI. Therefore, this study aims to delineate the demographic, epidemiological, and aetiological characteristics of hospitalised SARI patients in Central China between 2018 and 2020.

METHODS

Eligible patients with SARI admitted to the First Affiliated Hospital of Zhengzhou University between 1 January 2018 and 31 December 2020 were included in this retrospective study. Within the first 24 h of admission, respiratory (including sputum, nasal/throat swabs, bronchoalveolar lavage fluid, thoracocentesis fluid, etc.), urine, and peripheral blood specimens were collected for viral and bacterial testing. A multiplex real-time polymerase chain reaction (PCR) diagnostic approach was used to identify human influenza virus, respiratory syncytial virus, parainfluenza virus, adenovirus, human bocavirus, human coronavirus, human metapneumovirus, and rhinovirus. Bacterial cultures of respiratory specimens were performed with a particular focus on pathogenic microorganisms, including S. pneumoniae, S. aureus, K. pneumoniae, P. aeruginosa, Strep A, H. influenzae, A. baumannii, and E. coli. In cases where bacterial culture results were negative, nucleic acid extraction was performed for PCR to assay for the above-mentioned eight bacteria, as well as L. pneumophila and M. pneumoniae. Additionally, urine specimens were exclusively used to detect Legionella antigens. Furthermore, epidemiological, demographic, and clinical data were obtained from electronic medical records.

RESULTS

The study encompassed 1266 patients, with a mean age of 54 years, among whom 61.6% (780/1266) were males, 61.4% (778/1266) were farmers, and 88.8% (1124/1266) sought medical treatment in 2020. Moreover, 80.3% (1017/1266) were housed in general wards. The most common respiratory symptoms included fever (86.8%, 1122/1266) and cough (77.8%, 986/1266). Chest imaging anomalies were detected in 62.6% (792/1266) of cases, and 58.1% (736/1266) exhibited at least one respiratory pathogen, with 28.5% (361/1266) having multiple infections. Additionally, 95.7% (1212/1266) of the patients were from Henan Province, with the highest proportion (38.3%, 486/1266) falling in the 61-80 years age bracket, predominantly (79.8%, 1010/1266) seeking medical aid in summer and autumn. Bacterial detection rate (39.0%, 495/1266) was higher than viral detection rate (36.9%, 468/1266), with the primary pathogens being influenza virus (13.8%, 175/1266), K. pneumoniae (10.0%, 127/1266), S. pneumoniae (10.0%, 127/1266), adenovirus (8.2%, 105/1266), P. aeruginosa (8.2%, 105/1266), M. pneumoniae (7.8%, 100/1266), and respiratory syncytial virus (7.7%, 98/1266). During spring and winter, there was a significant prevalence of influenza virus and human coronavirus, contrasting with the dominance of parainfluenza viruses in summer and autumn. Respiratory syncytial virus and rhinovirus exhibited higher prevalence across spring, summer, and winter. P. aeruginosa, K. pneumoniae, and M. pneumoniae were identified at similar rates throughout all seasons without distinct spikes in prevalence. However, S. pneumoniae showed a distinctive pattern with a prevalence that doubled during summer and winter. Moreover, the positive detection rates of various other viruses and bacteria were lower, displaying a comparatively erratic prevalence trend. Among patients admitted to the intensive care unit, the predominant nosocomial bacteria were K. pneumoniae (17.2%, 43/249), A. baumannii (13.6%, 34/249), and P. aeruginosa (12.4%, 31/249). Conversely, in patients from general wards, predominant pathogens included influenza virus (14.8%, 151/1017), S. pneumoniae (10.4%, 106/1017), and adenovirus (9.3%, 95/1017). Additionally, paediatric patients exhibited significantly higher positive detection rates for influenza virus (23.9%, 11/46) and M. pneumoniae (32.6%, 15/46) compared to adults and the elderly. Furthermore, adenovirus (10.0%, 67/669) and rhinovirus (6.4%, 43/669) were the primary pathogens in adults, while K. pneumoniae (11.8%, 65/551) and A. baumannii (7.1%, 39/551) prevailed among the elderly, indicating significant differences among the three age groups.

DISCUSSION

In Central China, among patients with SARI, the prevailing viruses included influenza virus, adenovirus, and respiratory syncytial virus. Among bacteria, K. pneumoniae, S. pneumoniae, P. aeruginosa, and M. pneumoniae were frequently identified, with multiple infections being very common. Additionally, there were substantial variations in the pathogen spectrum compositions concerning wards and age groups among patients. Consequently, this study holds promise in offering insights to the government for developing strategies aimed at preventing and managing respiratory infectious diseases effectively.

A comparison of the prevalence of respiratory pathogens and opportunistic respiratory pathogenic profile of 'clean' and 'unclean' removable dental prostheses

OBJECTIVES

To determine and compare the opportunistic respiratory pathogenic index (ORPI) and prevalence of respiratory pathogens between clean and unclean removable prostheses.

METHODS

A cross-sectional study was conducted among 97 removable prosthesis wearers at a teaching dental hospital. Participants' prosthesis hygiene was grouped into clean and unclean. After prosthesis plaque samples were sequenced using the Type IIB Restriction-site Associated DNA Sequencing for Microbiome method, the prevalence was assessed for the presence of respiratory pathogens on each sample. The ORPIs for clean and unclean prostheses were quantified based on the sum of the relative abundance of respiratory pathogenic bacteria in a microbiome using a reference database that contains opportunistic respiratory pathogens and disease-associated information.

RESULTS

A total of 30 opportunistic respiratory pathogens were identified on the removable prostheses. Eighty-one (83.5 %) removable prostheses harboured respiratory pathogenic bacteria. Stenotrophomonas maltophilia (34.0 %), Pseudomonas aeruginosa (27.8 %), and Streptococcus agalactiae (27.8 %) were the top three prevalent respiratory pathogens detected in plaque samples. There was a significantly higher prevalence of respiratory pathogens residing on unclean than clean prostheses (P = 0.046). However, the ORPIs in both groups showed no statistically significant difference (P = 0.516).

CONCLUSIONS

The ORPIs for both clean and unclean prostheses demonstrated a similar abundance of respiratory pathogens. However, the high prevalence of respiratory pathogens residing on unclean prostheses should not be underestimated. Therefore, maintaining good prosthesis hygiene is still important for overall oral and systemic health, even though the direct link between prosthesis cleanliness and reduced abundance of respiratory pathogens has not been established.

CLINICAL SIGNIFICANCE

The association between the prevalence of respiratory pathogens and unclean removable prostheses has been demonstrated and might increase the theoretical risk of respiratory disease development.

Mycoplasma mycoides subspecies capri, an uncommon mastitis and respiratory pathogen isolated in a German flock of goats

Mycoplasma mycoides ssp. capri (Mmc) is one of the etiological microorganisms of contagious agalactia, which is among the diseases causing the highest economical losses in small ruminants. We report a disease outbreak in a German flock that led to significant suffering of goats characterized by mastitis, arthritis, pleuropneumonia and sudden deaths. Mmc was persistently isolated from many animals both from milk, and from a number of different swab and tissue samples. A number of closely related Mycoplasma spp. have to be taken into consideration to rule out important animal epizootics listed by European Animal Health Law and the World Organisation for Animal Health (WOAH). Some goats developed cross-reacting antibodies against Mycoplasma mycoides ssp. mycoides. Although Mmc is believed to be an uncommon microorganism in Germany, this study highlights that veterinarians should consider this pathogen in their work during herd health monitoring in Central Europe. Although eradication was not fully achieved, autogenous vaccination significantly seemed to improve animal health and welfare.

Development and evaluation of a multiplex digital PCR method for sensitive and accurate detection of respiratory pathogens in children

The emergence of multiplex digital polymerase chain reaction (dPCR) and other detection technologies for respiratory pathogens in recent years has facilitated greater understanding of respiratory virus epidemics. In this study, a multiplex dPCR method was developed and evaluated as a means of detecting five respiratory pathogens in children with acute lower respiratory tract infection (ALRTI). With 139 nasopharyngeal swabs collected from children with ALRTI, pathogens were detected using dPCR and quantitative real-time PCR (qPCR) methods. Of those specimens, dPCR detected 86 positive cases, while qPCR identified 84. Moreover, dPCR exhibited higher sensitivity than qPCR, and displayed no cross-reactivity with common respiratory pathogens. These findings suggest that dPCR-based method could become one of the most promising options for acute respiratory pathogen detection.

Comparison of "hock-a-loogie" saliva versus nasopharyngeal and oropharyngeal swabs for detecting common respiratory pathogens

Self-collection of saliva samples has attracted considerable attention in recent years, particularly during the coronavirus disease 2019 pandemic. However, studies investigating the detection of other common respiratory pathogens in saliva samples are limited. In this study, nasopharyngeal swabs (NPS), oropharyngeal swabs (OPS), and "hock-a-loogie" saliva (HLS) were collected from 469 patients to detect 13 common respiratory pathogens. Overall positivity rates for NPS (66.1 %), HLS (63.5 %), and OPS (57.8 %) were statistically different (P = 0.028), with an overall concordance of 72.7 %. Additionally, detection rates for NPS (85.9 %) and HLS (83.2 %) for all pathogens were much higher than for OPS (73.3 %). Coronavirus and human rhinovirus were most frequently detected pathogens in NPS (P < 0.001). Mycoplasma pneumoniae was significantly more prevalent in the HLS group (P = 0.008). In conclusion, NPS was a reliable sample type for detecting common respiratory pathogens. HLS was more easily collected and can be used in emergencies or specific conditions. Mixed NPS/OPS and NPS/HLS specimens have the potential to improve detection rates, although OPS testing alone has a relatively high risk for missed detection.

Clinical influence of multiplex PCR routine uses in urgent pediatric admissions

BACKGROUND

The coronavirus disease 2019 outbreak has prompted some hospitals to implement screening tests upon admission since 2019. FilmArray® Respiratory 2.1 Panel (FilmArray) is a multiplex polymerase chain reaction (PCR) test with high sensitivity and specificity for detecting respiratory pathogens. We aimed to assess the clinical influence of FilmArray routine use for pediatric patients, including those without symptoms suggestive of an infection.

METHODS

We conducted a single-center retrospective observational study, which investigated patients aged ≤ 15 years who underwent FilmArray on admission in 2021. We collected the patients' epidemiological information, symptoms, and FilmArray results from their electronic health records.

RESULTS

A positive result was observed in 58.6% of patients admitted to the general ward or intensive care unit (ICU) but only in 1.5% of patients in the neonatal ward. Among the patients admitted to the general ward or ICU who tested positive, 93.3% had symptoms suggestive of infections, 44.6% had a sick contact before admission, and 70.5% had siblings. However, 62 (28.2%) out of 220 patients without the four (fever, respiratory, gastrointestinal, and dermal) symptoms also had positive results. Among them, 18 patients with adenovirus and three with respiratory syncytial virus were isolated to private rooms. However, 12 (57.1%) patients were discharged without symptoms suggestive of viral infection.

CONCLUSION

Multiplex PCR routine use for all inpatients may lead to excessive management of positive cases because FilmArray cannot quantify microorganisms. Thus, targets for testing should be considered carefully based on patients' symptoms and histories of sick contacts.

Comparison of infections with respiratory syncytial virus between children and adults: a multicenter surveillance from 2015 to 2019 in Beijing, China

The objective of this study is to investigate the epidemiological and clinical characteristics of the acute respiratory tract infections (ARTI) caused by respiratory syncytial virus (RSV) among the population of all age categories in Beijing, China. Outpatients and inpatients with ARTI were enrolled from 35 sentinel hospitals in Beijing between March 2015 and February 2019. They were interviewed and their medical records were collected using a standardized form. Their respiratory specimens were collected and tested for the nucleic acid of RSV. The RSV-positive specimens were further genotyped into RSV-A and RSV-B groups. A total of 29,923 cases were included in this study. RSV was detected in 623 (2%, 623/29923) patients, with 391 (62.8%) genotypd as RSV-A, 126 (20.2%) as RSV-B, and 106 (17.0%) untyped. The RSV epidemic season usually occurred between October and March covering approximately 90% of annual RSV infections. The RSV-infected children aged < 5 years accounted for 52.2% of the total RSV infections with cough and fever as the most common manifestations. The RSV-infected elderly adults aged ≥ 60 years have the second largest proportion (25.2%) with dyspnea and lymphocytopenia as the most common manifestations and showed an elevated rate of hospitalization, an increased rate of ICU admission, an extended length of hospital stay, and an elevated mortality compared to the RSV-infected children. The RSV infections aged ≥ 60 years old, as the second largest population of the total annual RSV infections, usually developed worse outcomes than children and should be taken seriously.

Distinguishing viruses responsible for influenza-like illness

The many respiratory viruses that cause influenza-like illness (ILI) are reported and tracked as one entity, defined by the CDC as a group of symptoms that include a fever of 100 degrees Fahrenheit, a cough, and/or a sore throat. In the United States alone, ILI impacts 9-49 million people every year. While tracking ILI as a single clinical syndrome is informative in many respects, the underlying viruses differ in parameters and outbreak properties. Most existing models treat either a single respiratory virus or ILI as a whole. However, there is a need for models capable of comparing several individual viruses that cause respiratory illness, including ILI. To address this need, here we present a flexible model and simulations of epidemics for influenza, RSV, rhinovirus, seasonal coronavirus, adenovirus, and SARS/MERS, parameterized by a systematic literature review and accompanied by a global sensitivity analysis. We find that for these biological causes of ILI, their parameter values, timing, prevalence, and proportional contributions differ substantially. These results demonstrate that distinguishing the viruses that cause ILI will be an important aspect of future work on diagnostics, mitigation, modeling, and preparation for future pandemics.

Sterilization of paper during crisis

Paper sheets represent one of the infection risk sources inside educational and administrative institutions under biological pandemics. So, the present study aimed to validate the efficiency of gamma radiation or dry heat techniques to sterilize contaminated paper sheets with different indicator pathogens while retaining their structure. The results showed that gamma radiation at 6, 12, or 24 kGy can successfully kill Gram-positive bacteria such as Bacillus cereus and Staphylococcus aureus, Gram-negative bacteria such as Escherichia coli and Salmonella typhi, and fungi such as Candida albicans. Moreover, dry heating at 100 °C for 60 min, 150 °C for 30 min, or 200 °C for 15 min can be successful in paper decontamination of all tested species. Surprisingly, scanning electron microscopy (SEM) micrographs proved that gamma radiation at 6 kGy, dry heat at 100 °C for 60 min or 150 °C for 30 min or 200 °C for 15 min, is suitable for paper sheet sterilization while maintaining their structure. Ultimately, dry heat is a simple, effective, fast, safe, and inexpensive technique for paper sterilization. It may be used as a precautionary step inside educational institutions, especially during written examination periods, to ensure a safe life for academic members during biological pandemics such as COVID-19.

[Respiratory Tract Infection Pathogen Spectrum Study of 376 Pneumoconiosis Inpatients in Chengdu]

OBJECTIVE

To investigate the status of infections caused by respiratory pathogens and the patterns of infections caused by pathogens in different seasons, age groups and stages of pneumoconiosis so as to explore the pathogen spectrum of respiratory tract infections in pneumoconiosis patients.

METHODS

The sputum samples of 376 pneumoconiosis patients admitted to an occupational disease hospital in Chengdu between January, 2017 and October, 2019 were collected. Clinical information of the patients was collected and lab tests were conducted to check for 23 kinds of common respiratory viruses, bacteria and fungi in the sputum. The relationship between seasons, ages, and different stages of pneumoconiosis and the pathogen detection rate was analyzed.

RESULTS

In the 376 sputum samples, the detection rates of pathogens, viruses, bacteria and fungi were 42.29% (159/376), 32.98% (124/376), 9.57% (36/376) and 6.12% (23/376), respectively. The six pathogens with the highest detection rates were parainfluenza virus, rhinovirus, influenza virus, Candida albicans, Klebsiella pneumoniae and Candida krousei. The severity of respiratory tract infection did not show significant difference in different seasons, age groups, and pneumoconiosis stages.

CONCLUSION

The pathogen spectrum of respiratory tract infections in patients with pneumoconiosis is complicated and the proportion of viral infection is high. However, the severity of the infection is not associated with age, seasonal, or pneumoconiosis staging differences.

Bacterial and fungal co-infections among COVID-19 patients in intensive care unit

This study aimed to investigate the frequency and characteristics of respiratory co-infections in COVID-19 patients in the intensive care unit (ICU). In this retrospective observational study, pathogens responsible for potential co-infections were detected by the bacterial culture, real-time polymerase chain reaction (RT-PCR), or serological fungal antigen tests. Demographic and clinical characteristics, as well as microbial results, were analyzed. Bacterial culture identified 56 (58.3%) positive samples for respiratory pathogens, with the most common bacteria being Burkholderia cepacia (18, 18.8%). RT-PCR detected 38 (76.0%) and 58 (87.9%) positive results in the severe and critical groups, respectively. Most common pathogens detected were Stenotrophomonas maltophilia (28.0%) and Pseudomonas aeruginosa (28.0%) in the severe group and S. maltophilia (45.5%) in the critical group. P. aeruginosa was detected more during the early stage after ICU admission. Acinetobacter baumannii and Staphylococcus aureus were more frequently identified during late ICU admission. Fungal serum antigens were more frequently positive in the critical group than in the severe group, and the positive rate of fungal serum antigens frequency increased with prolonged ICU stay. A high frequency of respiratory co-infections presented in ICU COVID-19 patients. Careful examinations and necessary tests should be performed to exclude these co-infections.

Evaluation of TaqMan Array card (TAC) for the detection of 28 respiratory pathogens

Background

Respiratory infections are a serious threat to human health. So, rapid detection of all respiratory pathogens can facilitate prompt treatment and prevent the deterioration of respiratory disease. Previously published primers and probes of the TaqMan array card (TAC) for respiratory pathogens are not sensitive to Chinese clinical specimens. This study aimed to develop and improve the TAC assay to detect 28 respiratory viral and bacterial pathogens in a Chinese population.

Methods

To improve the sensitivity, we redesigned the primers and probes, and labeled the probes with minor groove binders. The amplification efficiency, sensitivity, and specificity of the primers and probes were determined using target-gene containing standard plasmids. The detection performance of the TAC was evaluated on 754 clinical specimens and the results were compared with those from conventional methods.

Results

The performance of the TAC assay was evaluated using 754 clinical throat swab samples and the results were compared with those from gold-standard methods. The sensitivity and specificity were 95.4 and 96.6%, respectively. The lowest detection limit of the TAC was 10 to 100 copies/μL.

Conclusions

TAC is an efficient, accurate, and high-throughput approach to detecting multiple respiratory pathogens simultaneously and is a promising tool for the identification of pathogen outbreaks.

Simultaneous detection of 15 respiratory pathogens with a fluorescence probe melting curve analysis-based multiplex real-time PCR assay

Acute respiratory tract infections are common worldwide and caused by a great diversity of pathogens. A rapid and accurate diagnosis method of respiratory infection is crucial for timely clinical intervention. Here, by combining fluorescence melting curve analysis and multiplex real-time assay, we developed a novel method which can simultaneously detect 15 respiratory viruses. The specificity for target genes was 100%, as assessed with a panel of 47 respiratory pathogens, which indicated no cross-reactions. The assay's limits of detection at the nucleic acid level ranged from 5 copies/μL to 500 copies/μL nucleic acids. Compared with conventional culture method, our assay showed more than 75% sensitivity and 100% specificity for each respiratory pathogen in 384 clinical samples. Even more, the kappa correlation for all the pathogens ranged from 0.86 to 1.00. Overall, this method has the characteristics of high throughput, low cost and high sensitivity and precision, which demonstrated our method is well suited for routine clinical testing in respiratory infection.

Multiplexed detection and identification of respiratory pathogens using the NxTAG® respiratory pathogen panel

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NxTAG chemistry offers an easy workflow, low hands-on-time and scalable throughput.

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All post-extraction assay steps take place in a single, closed tube.

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Clinical performance of NxTAG RPP is comparable to that of the xTAG RVP assay.

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Analytical performance is also similar or better than xTAG and xTAG FAST assays.

The Luminex® NxTAG® Respiratory Pathogen Panel (NxTAG RPP) is an IVD-cleared assay for the simultaneous detection and identification of nucleic acids from 18 respiratory viruses and 2 (or 3 outside of the U.S.) atypical bacterial pathogens in nasopharyngeal swabs. Its scalability allows concurrent testing of up to 96 samples in a single batch. Nucleic acid extracted from 200 µL of raw specimen using the easyMAG® extractor is added directly to pre-plated, lyophilized bead reagents (LBRs), where multiplexed RT-PCR and hybridization to MagPlex-TAG™ microspheres occurs within a sealed reaction well using a single cycling program. Data acquisition is done on the MAGPIX® instrument which reads and sorts the reaction products directly from the sealed well following transfer of the assay plate from the thermal cycler. NxTAG is the newest innovation in bead-based nucleic acid chemistry developed by Luminex. Here we provide the detailed assay protocol and present data which describe the clinical and analytical performance characteristics of NxTAG RPP.

Identification of key genes in human airway epithelial cells in response to respiratory pathogens using microarray analysis

Background

Airway epithelium is the primary target for pathogens. It functions not only as a mechanical barrier, but also as an important sentinel of the innate immune system. However, the interactions and processes between host airway epithelium and pathogens are not fully understood.

Results

In this study, we identified responses of the human airway epithelium cells to respiratory pathogen infection. We retrieved three mRNA expression microarray datasets from the Gene Expression Omnibus database, and identified 116 differentially expressed genes common to all three datasets. Gene functional annotations were performed using Gene Ontology and pathway analyses. Using protein-protein interaction network analysis and text mining, we identified a subset of genes functioned as a group and associated with infection, inflammation, tissue adhesion, and receptor internalization in infected epithelial cells. These genes were further identified in BESE-2B cells in response to Talaromyces marneffei by Real-Time quantitative PCR (qRT-PCR). In addition, we performed an in silico prediction of microRNA-target interactions and examined our findings.

Conclusions

Using bioinformatics analysis, we identified several genes that may serve as biomarkers for the diagnosis or the surveillance of early respiratory tract infection, and identified additional genes and miRNAs that warrant further fundamental experimental research.

Electronic supplementary material

The online version of this article (10.1186/s12866-018-1187-7) contains supplementary material, which is available to authorized users.

Guinea pig infection with the intracellular pathogen Rhodococcus equi

Rhodococcus equi is an opportunistic, intracellular pathogen that causes pyogranulomatous pneumonia in foals and immunocompromised people. Currently, there is no experimental model of R. equi pneumonia other than intra-bronchial experimental infection of foals with R. equi, which is labor-intensive and costly. This study's objective was to develop a guinea pig (GP) model of R. equi pneumonia that would facilitate development of novel approaches for controlling and preventing this disease. Guinea pigs were infected with either 10¹, 10², 10³, or 10⁴ colony forming units (CFUs) of a virulent strain of R. equi using a Madison aerosol chamber, or 10⁶ or 10⁷ CFUs of this strain intratracheally. Animals were monitored daily for clinical signs of pneumonia, and were euthanized and necropsied on days 1, 3, 7, or 35 post-infection (PI). Lung homogenates were plated onto selective agar to determine bacterial load. No clinical signs of disease were observed regardless of the inoculum dose or infection method. No bacteria were recovered from GPs euthanized at 35 days PI. Histology and immunostaining of T-cells, B-cells, and macrophages in lungs showed that inflammatory responses in infected GPs were similarly unremarkable irrespective of dose or route of infection. Guinea pigs appear to be resistant to pulmonary infection with virulent R. equi even at doses that reliably produce clinical pneumonia in foals.

Clinical Course and Factors Associated with Asthma Control in Children under Control-based Asthma Management: A Prospective Study

In the current study, we sought to track the clinical course of children under control-based asthma management and focused on respiratory pathogens monitoring. We prospectively explored influencing factors for asthma control. 121 children with uncontrolled asthma between 3-14 years of age were recruited. Common respiratory pathogens were detected with pharyngeal swabs and serum aeroallergen-specific IgE was measured. Numeric asthma control scores, airway resistance and fractional concentrations of exhaled nitric oxide (FENO) were evaluated. A proper control-based asthma management plan was established by the study physician. Regular reviews were performed, with the above measurements retested at set time intervals. The proportion of patients achieving asthma control at 1 month and 3 months were 59% and 76% ; respectively (p=0.013). These patients exhibited significant improvement in numeric scores and lung function parameters. The prevalence of common respiratory pathogens did not significantly differ between reviews. The number of sensitized aeroallergens significantly increased with age (r=0.235, p=0.010). Children with a high visual analogue scale (VAS) score for asthma at baseline were less likely to achieve asthma control after 1 month, while those sensitized to more aeroallergens were more likely to achieve asthma control after 1 month (p=0.016 and 0.012). In summary, children with asthma showed significant improvements in control rates and lung function during control-based asthma management, independent of respiratory pathogens testing reults. Patients with high VAS scores and fewer sensitizations to aeroallergens had difficulty achieving short-term asthma control.

Occurrence of Pasteurella multocida among pigs with respiratory disease in China between 2011 and 2015

BACKGROUND

Prior to the 1990s, P. multocida capsular serogroup A was the most prevalent in China, followed by serogroups B and D. Thirty years later, serogroup D became the most prevalent, followed by serogroups A and B. However, the P. multocida capsular serogroups currently circulating in China remain unclear. Therefore, the aim of the present study was to provide an update on P. multocida serogroups isolated from diagnostic samples collected from clinically diseased pigs in Central and Eastern China from 2011 to 2015.

RESULTS

Between February 2011 and October 2015, 296 isolates of Pasteurella multocida were collected from 3212 pigs with clinical respiratory disease in 12 provinces of China (isolation rate of 9.2%). Of the 296 collected isolates, 146 (49.3%) were P. multocida capsular type A, 141 (47.6%) were capsular type D, and one was capsular type B. Streptococcus suis (94/193; 48.7%), Haemophilus parasuis (76/193; 39.3%), Escherichia coli (53/193; 27.5%), and Bordetella bronchiseptica (26/193; 13.5%) were frequently isolated together with P. multocida. A total of 14 toxigenic P. multocida strains co-isolated with other pathogens from 32 cases of atrophic rhinitis were classified into serogroup D. The virulence of P. multocida capsular type A isolates was higher than that of capsular type D isolates based on LD₅₀ studies in mice.

CONCLUSIONS

Over the past 5 years, P. multocida capsular type A was the most frequently isolated from diagnostic submissions in Central and Eastern China, followed by serogroups D and B.

The modified Gingyo-san, a Chinese herbal medicine, has direct antibacterial effects against respiratory pathogens

BACKGROUND

Modified Gingyo-san (MGS) is empirically used to treat various respiratory infections. MGS has been reported to have antiinflammatory and antiviral activities; however, it is not known if it has an antibacterial activity. Therefore, in this study, we aimed to investigate the antimicrobial activity of MGS against respiratory pathogens.

METHODS

MGS, which is sold as an over-the-counter drug in Japan, was used for the study. Antimicrobial activity was evaluated using the disk diffusion method. Growth inhibitory activity was evaluated by measuring colony-forming units of the pathogens in the presence of MGS.

RESULTS

MGS inhibited the growth of Bacillus subtilis, Streptococcus pneumoniae, and Streptococcus pyogenes, which are gram-positive bacteria. Although the growth of most gram-negative bacteria was not inhibited by MGS, interestingly, the growth of Haemophilus influenzae was inhibited. MGS did not show any activity against Candida albicans or bacteriophage φX174.

CONCLUSIONS

In addition to the antiinflammatory and antiviral activities of MGS, which have already been reported, the data obtained from this study indicates that MGS has an antibacterial activity.