The First Reported Case of Co-Infection with Neisseria Meningitidis and Bordetella Pertussis in the Cerebrospinal Fluid Specimen of a Normal Four-Year-Old Child

Pertussis is an acute and highly contagious respiratory disease caused by Bordetella pertussis(B.pertussis),which occurs in people of all ages and is most dangerous for young children,especially infants.The introduction of whole-cell pertussis vaccines(wPVs)in the 1950s dramatically reduced the incidence of pertussis worldwide[1].However,over the past two decades,many studies have reported the resurgence of pertussis in different countries[2].Epidemiological surveillance in Hubei Province over the last 3 years revealed a clear increasing trend in the incidence of pertussis during the coronavirus disease 2019(COVID-19)epidemic.

Antibody Levels and Infection Status of Pertussis in the Population under Pertussis Resurgence in Guangxi in 2018:A Cross-Sectional Survey

Objective Pertussis cases have increased markedly since 2018 in Guangxi.The aim of this study was to evaluate antibody levels and the infection status of pertussis in the resident population.Method A total of 10,215 serum samples from residents were collected from August-November 2018 and tested for anti-pertussis IgG and toxin IgG using the enzyme-linked immunosorbent assay(ELISA).Results Of the collected samples,1,833(17.94%)tested positive for anti-pertussis IgG,with the median concentration of 16.06 IU/mL.Antibody level<10 IU/mL accounted for more than 60%in children under 4 years of age,but declined with age,whereas the percentages of the other three levels(10-40,40-50,and≥50 IU/mL)increased almost with age(P<0.001).Moreover,7,924 samples were selected for anti-pertussis toxin IgG,of which 653(8.24%)tested positive(≥40 IU/mL)with the median concentration of 5.89 IU/mL,and 204 participants(2.56%)had recent pertussis infection(≥100 IU/mL).Among the different age groups,the highest rates of positivity and recent infection were observed at 11-20 years of age,the lowest positivity rate at 5 years of age,and the lowest recent infection rate at 4 years of age(P<0.001,P=0.005,respectively).Conclusion The survey results showed that all age groups in Guangxi lacked immunity against pertussis,which was one of the main factors contributing to the resurgence of pertussis in 2018.In addition,the prevalence of pertussis is relatively high in Guangxi,and its incidence is seriously underestimated,especially in adolescents and adults.

Research on pharmacological mechanism of the treatment of Asthma by oral Bordetella pertussis

Objective To examine the effect of oral Bordetella pertussis on the asthma mice sensitized by ovalbumin(OVA),and explore the possible mechanism.Methods Culture the B.pertussis in Bordet-Gengou agar containing 25% rabbit blood.Collect the bacteria and inactive them at 80 ℃ for 30 min to get whole killed B.pertussis.32 BALB/C mice were randomly divided into control group,model-control group,model group and treatment group.The mice were sensitized and challenged with OVA to establish asthma model.Asthma mice in treatment group were orally administrated with B.pertussis 7 days before sensitization.The mice in control group and model-control group were challenged with saline.After 24 hours of last challenge,bronchoaveolar lavage fluid(BALF)and peripheral blood were collected.The total cells and eosinophils were counted in BALF.Results Compared with the control group(2.03±0.42,0.33±0.82)×105 mL-1 and model-control group(2.16±0.48,0.16±0.41)×105 mL-1,the total cells(10.13±1.33)×105 mL-1 and eosinophils(11.83±4.573)×105 mL-1 in BALF were more in asthma mice(P<0.01).The number of total cells(5.50±1.55)×105 mL-1 and eosinophils(0.66±0.82)×105 mL-1 in BALF were reduced in asthma mice treated with B.pertussis compared with asthma mice(P<0.01).Conclusions Oral B.pertussis can inhabit airway inflammation of asthma mice and has the potential of treating asthma.

30 and 32 kDa outer membrane proteins of Bordetella pertussis as a modulator on promoting degranulation of mast cells

The correlation between the activities of the outer menbrane proteins （OMPs） of Bordetella pertussis and the lgE-mediated asthma was investigated in the present study, in which the OMPs of B. pertussis and their components were prepared by detergent treatment and chromatography, and the molecular weights of the OMPs components were determined by SDS-PAGE. The amounts of total as well as the ovalbumin （OVA）-specific IgE induced by dead B. pertussis whole bacterial vaccine on guinea pigs were detected by ELISA. Meanwhile, the effect of the OMPs and their components to promote the degranulation of guinea pig mast cells was observed by using the mast cell degranulation test, and ELISA assay was used to measure the histatmine levels in the supematants from the mast cell cultures. Histamine sensitive test was used to demonstrate the effects of the OMPs and their components to increase the histamine lethal sensitivity in mice. It was found that four components with molecular weights of 30, 32, 38 and 69 kDa could be obtained from the OMPs of B. pertussts, and the dead whole bacteria vaccine of B. pertussis had the ability to increase the levels of the total as well as the OVA-specific IgE in sera of guinea pigs. The OMPs and their 30 and 32 kDa components demonstrated significantly enhancing effect on the degranulation of guinea pig mast cells, and the histamine levels in the supematants from the mast cell culture treated with OMPs and their 30 and 32 kDa components were also significantly increased. It is evident that the strong adjuvant activity and the enhancing effect to degranulation of mast cells and the release of histamine of certain outer membrane components of B. pertussis could be demonstrated as revealed by the results of the present study, suggesting the possibility of a close relationship between the infection of vaccination with B. pertussis and the IgE-mediated asthma.

Epidemiological Characteristics and Risk Factors of the Pertussis in Infants < 12 Months of Age in Tianjin, China

The epidemiologic characteristics of 631 infant pertussis cases 〈 12 months, which accounted for 57.42% of the total cases, were analyzed by descriptive epidemiology in Tianjin, between 2010 and 2015. The incidence of infants was 104.66/100,000, which was 118 times higher than in other age groups （P 〈 0.001）. The primary type of pertussis simultaneously presented in households was adult-to-infant （70.51%）. The parents were identified as the source of infection in 80.18% of cases for infants. The positive rate of placental antibody transfer was 31.06% and 3.13% for 3-month-old infants. Infants presented the highest age-specific pertussis incidence. The most important reason was parents were the important sources of infection, and secondly the lower level of antibodies in neonates and the rapid waning of maternal antibody titer.

Risk factors for pertussis among children hospitalized for pertussis during 2016-2017, in Guizhou Province of China: a case-control study

Aim:Pertussis is a respiratory tract infection,the vaccine for which was introduced in the Expanded Programme on Immunization(EPI)in Guizhou Province of China(hereafter referred as Guizhou)in the 1980s.This vaccine rapidly decreased incidence rates of pertussis in the province,however,despite the wide high coverage of the diphtheria,tetanus and acellular pertussis(DTaP)combined vaccine,there has been a resurgence of pertussis since 2014.Even with this recent increase in disease transmission,risk factors for pertussis infection have not been evaluated in Guizhou.We aimed to provide information on pertussis risk factors and insight on designing targeted pertussis control policies and measures through this study.Methods:A 1:2 matched retrospective case-control study was conducted between 2016 and 2017,involving infants and children younger than 6 years old and parents of the participants.The enrolled cases included clinical and laboratory confirmed pertussis cases according to the WHO-recommended pertussis definition.Controls were selected from children in the same neighborhood who were not diagnosed with pertussis prior to our investigation and did not exhibit any clinical manifestations of pertussis.Results:The household size[Matched odds ratio(OR_(m)=1.4,95%confidence interval(Cl):1.1-1.7]and household members with antecedent cough(OR_(m)=3.6,95%CI:1.8-7.2)were significantly associated with their child’s pertussis onset.The parents’occupations were significantly associated with their child’s pertussis onset(ORm=9.4,95%CI:1.6-54.8,for mother side;ORm=4.5,95%CI:1.2-16.5,for father side),when they worked in the business and/or service industry.Having family members with a history of cough was an independent risk factor for pertussis[Adjusted odds ratio(AOR)=43.6,95%CI:2.7-694.0].Besides,the parents’demographic characteristics and DTaP doses were not found to be independent factors.Conclusion:Household exposure is an important risk factor for pertussis infection in infants and young children and should therefore be considered as a major factor during formulation of pertussis control policies and measures.

Characterization of two Achromobacter xylosoxidans isolates from patients with pertussis-like symptoms

Objective:To characterize two Achromobaeter xylosoxidans recovered from 2 patients diagnosed with pertussis during a Bordetella pertussis surveillance program.Methods:Nasopharyngeal swabs from 2 children under 1 year of age with clinical suspicion of pertussis were analyzed by culture and PCR.Results:Two Achromobaeter xylosoxidans A8,closely related to Bordetella spp.were recovered from 2 patients diagnosed of pertussis,both carrying the ptxA gene and IS418 the pertussis toxin encoding gene.Subsequently,antibiotic susceptibility was evaluated by disk-diffusion method and by PCR.Conclusions:Although more detailed studies are needed,the present data highlight the possibility that Achromobaeter xylosoxidans.closely related Bordetella pertussis microorganisms and not covered under the vaccine umbrella,might also result in cases of whooping cough.Thereby further surveillance is necessary to determine the extension and relevance of their pathogenic role in order to discriminate their real public health implication.

Investigation of the epidemiology,pathogenicity and immunogenicity of Bordetella bronchiseptica isolated from cats and dogs in China from 2021 to 2023

Bordetella bronchiseptica(Bb)is recognized as a leading cause of respiratory diseases in dogs and cats.However,epidemiological data on Bb in dogs and cats in China are still limited,and there is no commercially available vaccine.Live vaccines containing Bb that are widely used abroad are generally efective but can establish latency and potentially reactivate to cause illness in some immunodefcient vaccinated recipients,raising safety concerns.In this study,34 canine-derived and two feline-derived Bb strains were isolated from 1809 canine and 113 feline nasopharyngeal swab samples collected from eight provinces in China from 2021 to 2023.The PCR results showed that the percentage of positive Bb was 22.94%(441/1922),and more than 90%of the Bb isolates had four virulence factor-encoding genes(VFGs),namely,fhaB,prn,betA and dnt.All the isolated strains displayed a multidrug-resistant phenotype.The virulence of 10 Bb strains isolated from dogs with respiratory symptoms was tested in mice,and we found that eight isolates were highly virulent.Furthermore,the eight Bb isolates with high virulence were inactivated and intramuscularly injected into mice,and three Bb strains(WH1218,WH1203 and WH1224)with the best protective efcacy were selected.Dogs immunized with these three strains exhibited strong protection against challenge with the Bb feld strain WH1218.Ultimately,the WH1218 strain with the greatest protection in dogs was selected as the vaccine candidate.Dogs and cats that received a vaccine containing 109 CFU of the inactivated WH1218 strain showed complete protection against challenge with the Bb feld strain WH1218.This study revealed that Bb is an important pathogen that causes respiratory diseases in domestic dogs and cats in China,and all the isolates exhibited multidrug resistance.The present work contributes to the current understanding of the prevalence,antimicrobial resistance,and virulence genes of Bb in domestic dogs and cats.Additionally,our results suggest that the WH1218 strain is a promising candidate safe and efcacious inactivated Bb vaccine.

Aberration detection of pertussis from the Mazandaran province, Iran, from 2012 to 2018: Application of discrete wavelet transform

Objective:To define the level of alarm threshold for pertussisaberrations and to detect the aberrations of the reported suspectedcases of pertussis from the Mazandaran province in the north ofIran.Methods:The included cases were composed of the suspectedpertussis patients who came from Mazandaran province andregistered in the Center for Disease Control and Prevention from20 March 2012 to 20 March 2018.A discrete wavelet transformbasedmethod was used to detect the aberrations.All analyseswere performed using MATLAB Software version 2018a andExcel 2010.Results:A total of 1162 cases were recruited in the study,including 545(46.90%)males and 617(53.10%)females,withmedian age of 1.47(0.22-9.56)years.The median age of maleswas 1.18(0.21-8.24)years,while that of females was 1.82(0.21-10.75)years.Concerning the level of the alarm threshold,it was1.28 case/d when k=2,while it was 1.34 case/d when k=3.Thetotal detected aberration days were 123 d and 57 d by consideringk=2 and 3,respectively.The most defined alarm threshold wasrelated to spring(>2 cases/d)and summer(>1 case/d),respectively.Conclusions:The sensitivity of the surveillance system issubjected to a different time.Thus,determining the level of alarmthreshold periodically using different methods is recommended.

Comparative Pertussis Antibody Response of Nigerian Children to Diphtheria, Pertussis, Tetanus (DPT) and Pentavalent Vaccines

Background: In Nigeria Pentavalent vaccine had replaced Diphtheria-Pertussis- Tetanus [DPT] vaccine in the prevention of pertussis since 2012. Aims and Objectives: The aim of this study was to compare the anti-pertussis immunoglobin G (IgG) response of children who received DPT with those who received the pentavalent vaccine. Subjects and Methods: This study was carried out in Akpabuyo LGA of Cross River State from April to June 2016. It was a cross-sectional survey of anti-pertussis IgG levels in children aged 6 months to 5 years who received DPT and those who received pentavalent vaccine. IgG antibody levels were determined using enzyme-linked immunosorbent assay. The protective level was set at >11 DU according to manufacturer’s cut off point. Results: Seventy eight out of 230 children [33.9%] who had received DPT had protective levels of anti-pertussis IgG compared to 74 out of 192 children [38.5%] who had received pentavalent vaccine. The difference was not statistically significant [p = 0.61]. The median IgG antibody level in those who received DPT was 8.0 DU (interquartile range (IQR) 4.0 - 13.0) compared with 9.0 DU (IQR) 4.0 - 15.0 in those who received pentavalent vaccine [p = 0.18]. No single factor investigated predicted the development of protective levels of antibody in the multivariate analysis. Conclusion/Recommendation: There was no difference in the antipertussis antibody response between DPT and pentavalent vaccines recipients. Further study is needed to elucidate factors that could be responsible for low anti-pertussis antibody response in this population.

Difference of the Pain during the DPT (Diphtheria-Pertussis-Tetanus) Vaccination

Background: The objective of this study is to determine whether analyze of the infant’s pain associated with diphtheria-pertussis-tetanus (DPT) immunization is useful for vaccination in children. It is not known whether the immunization pain can be prevented with the adequate choice of DPT vaccines among several manufacturers in Japan. Further, it is not clear whether the difference of the reaction during vaccination between gender and age. Design: Three manufacturer’s Japanese DPT vaccines were used in this study. The parents assessed their infant’s pain on a modified visual analogue scale (MVAS), the start of the crying and total crying time during the immunization. Results: The A manufacturer’s DPT vaccine was significantly lower on the proportion of crying, the duration of crying and MVAS score than the other two manufacturer’s DPT vaccines. The proportion of crying, the duration of crying and MVAS score was lower in the boy than in the girl. On the other hand, it had not found the difference of their reactions with age. Conclusions: Our studies have found that the adequate choice of DPT vaccine decreased vaccination pain. The studies also indicate that some tendencies with vaccinations were shown in children. To consider these tendencies was useful in performing less painful vaccination.

Emergence of Erythromycin-Resistant and Pertactin-and Filamentous Hemagglutinin-Deficient Bordetella pertussis Strains—Beijing,China,2022-2023

What is already known about this topic?Pertussis has reemerged as a significant public health threat,primarily due to variations in Bordetella pertussis strains,antimicrobial resistance,and vaccine evasion.What is added by this report?All isolated strains were identified as ptxA1/ptxC2/ptxP3/prn150/fim2-1/fim3-1/fhaB1/tcfA2 type and exhibited resistance to erythromycin.

<i>Bordetella holmesii</i>: Comparison of Two Isolates from Blood and a Respiratory Sample

Interest in Bordetella holmesii is increasing, but very little is known about this bacterium, which can be isolated from both blood and respiratory samples. In this study, we compared a B. holmesii isolate from the blood sample of an adult with bacteremia with another isolate from a nasopharyngeal swab from an adult with whooping cough syndrome. Genetic analysis was carried out, targeting relevant genes, and virulence properties were studied in cellular and animal models. Our genomic analysis provided no evidence of traits specific to either blood or respiratory isolates of B. holmesii. Neither isolate was cytotoxic to human tracheal epithelial cells. Both isolates were only weakly invasive and they did not persist within epithelial cells for less than 48 h.

Presence of <i>Actinobacillus pleuropneumoniae, Streptococcus suis, Pasteurella multocida, Bordetella bronchiseptica, Haemophilus parasuis and Mycoplasma hyopneumoniae</i>in upper respiratory tract of swine in farms from Aguascalientes, Mexico

Respiratory diseases are one of the most important health problems in pig herds. The porcine respiratory disease complex (PRDC) is the term used to describe pneumonic diseases caused by multiple infectious agents that provoke weight loss in animals or death. In the PRDC multiple pathogens (bacteria and/or viruses) work in combination to induce this respiratory disease. Within this complex, Actinobacillus pleuropneumoniae, Streptococcus suis, Pasteurella multocida, Bordetella bronchiseptica, Haemophilus parasuis and Mycoplasma hyopneumoniae are the main bacterial pathogens involved in great economic losses to the swine industry. The aim of this work was to estimate the presence of A. pleuropneumoniae, S. suis, P. multocida, B. bronchiseptica, H. parasuis and M. hyopneumoniae in the upper respiratory tract of pigs in representative swine farms inAguascalientes,Mexico, using PCR technique. The study was performed in 14 swine farms. We obtained a total of 212 nasal swabs. Near 20% of samples were positive for A. pleuropneumoniae (located in the 79% of farms);17% were positive for S. suis (in 86% of farms), of these, 3% were S. suis serovar 2;30% were positive for H. parasuis (93% of farms);23% of the samples to P. multocida (in 79% of farms);and 19% to M. hyopneumoniae (in 64% of farms). B. bronchiseptica was not detected in this study. The results obtained show that bacterial pathogens of PRDC were present in the upper respiratory tract of pigs in all farms studied;therefore, these pathogens are widely disseminated in pig farms of Aguascalientes, Mexico.

Immunoproteomic Analysis of Bordetella bronchiseptica Outer Membrane Proteins and Identification of New Immunogenic Proteins

Bordetella bronchiseptica is a Gram-negative pathogen that causes acute and chronic respiratory infection in a variety of animals. To identify useful antigen candidates for diagnosis and subunit vaccine of B. bronchiseptica, immunoproteomic analysis was adopted to analyse outer membrane proteins of it. The outer membrane proteins extracted from B. bronchiseptica were separated by two-dimensional gel electrophoresis and analyzed by Western blotting for their reactivity with the convalescent serum against two strains. Immunogenic proteins were identified by matrix-assisted laser desorption/ionization time of flight-mass spectrometry（MALDI-TOF-MS）, a total of 14 proteins are common immunoreactive proteins, of which 1 was known antigen and 13 were novel immunogenic proteins for B. bronchiseptica. Putative lipoprotein gene was cloned and recombinantly expressed. The recombinant protein induced high titer antibody, but showed low protective indices against challenges with HB（B. bronchiseptica strain isolated from a infected rabbit）. The mortality of mice was 80% compared to 100% of positive controls. The identification of these novel antigenic proteins is an important resource for further development of a new diagnostic test and vaccine for B. bronchiseptica.

Isolation and characterization of Bordetella pseudohinzii in mice in China

We report on the first detection and isolation of B.pseudohinzii(Bordetella pseudohinzii)in laboratory mice in China.Forty‐one B.pseudohinzii strains were isolated from 3094 mice in 33 different laboratory animal facilities in southern China.The isolates were identified through culture and genome sequenceing.Phylogenetic analysis based on the sequences of 16S rRNA and OmpA genes demonstrated that these strains were on the same clade as other B.pseudohinzii strains isolated from mice.Experimental infected mice presented an asymptomatic infection.B.pseudohinzii replicated in both the respiratory tract and the digestive tract.Most importantly B.pseudohinzii shed via feces and infected a group of sentinel mice in a separate cage via cage padding contaminated with B.pseudohinzii‐positive feces,indicating that B.pseudohinzii could transmit efficiently among mice and contaminate environmental facilities.Our study highlights the importance of routine monitoring of the pathogen in laboratory mice and provides vital insights into the transmission of Brodetellae in rodents and human.

Phenotypic and Genetic Characteristics of a Bordetella hinzii Isolated from a Rex Rabbit

A Bordetella hinzii strain, isolated from the lung of a dead breast-feeding infant rex rabbit with a respiratory infection, was used as study object to investigate its phenotypic and genetic characteristics. The strain could grow on MacConkey agar and was gram-negative, oxidase-positive, catalase-positive, short rodshaped, and it can produce alkali from malonate. Its 6S rRNA sequence was partially identical with B. hinzii （AF177667）. Animal experiments revealed nasal mucous hyperemia, tracheal congestion and bronchopneumonia in 28-day old rex rabbits. To sum up, this Bordetella hinzii isolate was deemed as a novel causative agent of respiratory disease in rex rabbit.

<i>Bordetella bronchiseptica</i>pneumonia in a woman with lymphoma: A case report

A 62-year-old woman with splenic marginal zone lymphoma presented with fever, cough and bilateral pneumonia 11 days after chemotherapy. A bronchoalveolar lavage showed numerous leukocytes and Gramnegative bacilli that were identified as Bordetella bronchiseptica in culture. An antibiotherapy with minocycline and ciprofloxacin helped her to stop coughing. This unusual micro-organism, which has mainly an animal reservoir, is a rarely cause of human infection, almost always in immunocompromised patients. The main problems in B. bronchiseptica infection are the difficulties of identification of this micro-organism and the recurrence of infection, which are a challenge for microbiologists and practitionners.

儿童重症百日咳临床特征及其影响因素分析

目的 探讨儿童重症百日咳的临床特征及其发生的影响因素。方法 回顾性收集2011年3月~2018年12月首都儿科研究所附属儿童医院收治的百日咳患儿的人口学及临床资料,根据百日咳的严重程度将患儿分为重症百日咳组和非重症百日咳组。比较两组间各指标,并探讨发生重症百日咳的影响因素。结果 在227例百日咳患儿中,重症百日咳组有54例(23.8%),非重症百日咳组有173例(76.2%)。重症百日咳组发病年龄低于非重症百日咳组[1.35(0.60, 2.36)个月vs 3.93(1.19, 7.67)个月,P<0.01]。重症百日咳组中有阵发性痉挛性咳嗽、咳嗽后呕吐、阵发性青紫、咳嗽时面色潮红及发热的发生率分别高于非重症百日咳组(96.3%vs 81.5%、31.5%vs 13.9%、81.5%vs 9.8%、98.2%vs 76.9%和51.9%vs 27.2%,P<0.05)。重症百日咳组完成全程接种百日咳疫苗的比例低于非重症百日咳组(1.9%vs 19.1%,P<0.01),而重症百日咳组的未接种疫苗比例高于非重症百日咳组(94.4%vs 69.4%,P<0.01)。逐步Logistic回归分析结果显示,完成全程接种百日咳疫苗为减少重症百日咳发生的保护性因素(OR=0.07,95%CI:0.008~0.610,P=0.02)。结论 年龄越小尤其<3月龄的百日咳患儿越容易进展为重症百日咳,完成全程接种百日咳疫苗是减少儿童重症百日咳发生的保护性因素。

百日咳患儿血清IFN-γ、IL-5水平及其与免疫状态的关系

目的探讨百日咳患儿血清γ-干扰素(IFN-γ)、白细胞介素-5(IL-5)水平及其与免疫状态的关系。方法选取2021年1月至2023年12月该院儿科收治的300例百日咳患儿临床资料进行回顾性分析,根据患儿不同免疫状态分为未免疫组、部分免疫组和完全免疫组。比较3组患儿入院时血清IFN-γ、IL-5水平,并根据患儿年龄及完全免疫患儿接种时长进行分组,观察不同分组状况下患儿血清IFN-γ、IL-5水平。采用多因素Logistic回归分析百日咳患儿血清IFN-γ、IL-5水平及其与免疫状态的关系。结果完全免疫组患儿血清IFN-γ水平高于未免疫组和部分免疫组,血清IL-5水平低于未免疫组和部分免疫组,差异均有统计学意义(P<0.05);部分免疫组患儿IFN-γ水平高于未免疫组,血清IL-5水平低于未免疫组,差异均有统计学意义(P<0.05);>3~6岁患儿血清IFN-γ水平高于其他年龄段患儿,IL-5水平低于其他年龄段患儿,差异均有统计学意义(P<0.05);多因素Logistic回归分析结果显示,调整受试者白细胞计数、淋巴细胞比例后,与完全免疫患儿比较,部分免疫患儿和未免疫患儿血清IFN-γ每增加一个单位,认为百日咳患儿免疫功能下降风险增加0.886倍(95%CI:0.836~0.938);部分免疫患儿和未免疫患儿血清IL-5每增加一个单位,认为百日咳患儿免疫功能下降风险增加1.255倍(95%CI:0.161~1.357);完全免疫状态下不同接种时长患儿血清IFN-γ、IL-5水平比较,差异均无统计学意义(P>0.05)。结论不同免疫状态的百日咳患儿血清IFN-γ、IL-5水平存在一定差异,二者水平在一定程度上与患儿的免疫状态有关。