Pertussis is an acute, highly infectious respiratory disease caused by Bordetella pertussis, and is one of the leading causes of infant disease and death worldwide. The pertussis vaccine has been used in the expanded program on immunization globally since 1974 and the vaccination coverage remains high. In recent years, the pertussis incidence rate increased, even pertussis outbreaks occurred, in more and more countries or areas after years with low incidence level. The disease burden of pertussis has been seriously underestimated, and the prevention and control of pertussis is facing many challenges. This article reviews the epidemic status of pertussis worldwide, the factors affecting the reemergence of pertussis, and the challenges in the prevention and control to provide a reference for prevention and control of pertussis.
Infant ; Humans ; Whooping Cough/prevention & control* ; Vaccination ; Pertussis Vaccine/therapeutic use* ; Bordetella pertussis ; Disease Outbreaks

OBJECTIVE: To study the value of cleaved lymphocytes in peripheral blood smear in assisting the early diagnosis of pertussis. METHODS: Nasopharyngeal swabs and peripheral blood samples were collected from 107 children with pertussis-like disease. PCR-flow fluorescent hybridization was used to detect the nucleic acids of Bordetella pertussis. Based on the detection results, the children were divided into two groups: pertussis (n=52) and non-pertussis (n=55). According to age, the pertussis group was divided into two subgroups: <1 year old (n=42) and ≥1 year old (n=10). According to disease severity, the pertussis group was divided into another two subgroups: mild (n=45) and severe (n=7). An automatic blood cell analyzer was used to determine peripheral blood cell counts. Wright's staining and peroxidase staining were used to observe and count cleaved lymphocytes under a microscope. RESULTS: Cleaved lymphocytes in peripheral blood were round with small cytoplast, less cytoplasm and cleaved or lobulated nuclei. According to the negative peroxidase staining results, these cells were confirmed as lymphocytes. Compared with the non-pertussis group, the pertussis group had significantly higher leukocyte count, lymphocyte percentage, platelet count, and percentage of cleaved lymphocytes (P<0.001). For the children with pertussis, the <1 year old subgroup had significantly higher lymphocyte percentage, platelet count, and percentage of cleaved lymphocytes than the ≥1 year old subgroup (P<0.05). The severe subgroup had slightly higher leukocyte count, lymphocyte percentage, platelet count, and percentage of cleaved lymphocytes than the mild subgroup (P>0.05). CONCLUSIONS The detection of cleaved lymphocytes combined with peripheral blood cell counts provides a new option for the early diagnosis of pertussis in children.
Bordetella pertussis ; Humans ; Infant ; Leukocyte Count ; Lymphocytes ; Platelet Count ; Whooping Cough

The Chinese and English names of pertussis or whooping cough show the important clinical features of the disease in terms of its course and cough characteristics respectively. In the clinical description of typical pertussis, the meanings of the Chinese and English words are not completely consistent, such as spastic cough versus paroxysmal cough, spasmodic stage/phase versus paroxysmal stage/phase, and "back-hook" versus whoop, and some descriptions in English are not seen in Chinese. This article aims to provide more comprehensive information for the understanding of pertussis by comparing the descriptions of typical clinical manifestations of pertussis in Chinese and English literatures and to put forward suggestions for the diagnosis of pertussis syndrome based on typical clinical manifestations.
Asian Continental Ancestry Group ; Bordetella pertussis ; Humans ; Language ; Whooping Cough

PURPOSE: Although the DTaP and Tdap vaccines used to prevent pertussis have been used for a long time, there is no standard method for measuring pertussis antigens. Therefore, this preliminary study was conducted to develop an enzyme-linked immunosorbent assay method using an animal model for measuring antibodies against pertussis toxin, the most important pertussis pathogenic antigen, in the sera of vaccinated mice. MATERIALS AND METHODS: Bordetella pertussis Tohama phase I was cultured for 24–30 hours, and then pertussis toxin was purified from the culture medium by chromatography. Purified pertussis toxin was diluted in phosphate-buffered saline-coating buffer, and 100 µL of diluted pertussis toxin was added to each well and reacted at room temperature for 4 hours. Positive serum was diluted to 1/1,250–1/80,000 and negative serum was diluted to 1/50 to determine the coating concentration with the optimal signal/noise ratio. Optimal test conditions were confirmed from the dilution factors of the secondary antibody and streptavidin horseradish peroxidase (SA-HRP). RESULTS: Optimal conditions were as follows: 4 µg/mL for coating antigen; 1/40,000 for secondary antibody; and 1/1,000 for the SA-HRP dilution factor. Comparison of the sera obtained from mice treated with a developing vaccine and commercial vaccine with National Institute for Biological Standard and Control standard serum under the established conditions showed the following results: 1,300.62, 534.94, and 34.85, respectively. CONCLUSION: The method developed in this study is suitable for measuring anti-pertussis toxin antibodies and may be applicable for clinical sample analysis or indirect diagnosis of pertussis.
Animals ; Antibodies ; Bordetella pertussis ; Chromatography ; Diagnosis ; Enzyme-Linked Immunosorbent Assay* ; Horseradish Peroxidase ; Methods ; Mice* ; Models, Animal ; Pertussis Toxin ; Streptavidin ; Vaccines ; Whooping Cough

OBJECTIVE: To investigate the alternative antimicrobial drugs for the treatment of neonatal pertussis and the antigen genotypes of Bordetella pertussis (B. pertussis) strains. METHODS: A total of 32 B. pertussis strains isolated from neonates between May 2013 and July 2018 were used in this study. E-test stripes were used to measure the minimal inhibitory concentration (MIC) of 18 antimicrobial drugs including erythromycin, sulfamethoxazole-trimethoprim (SMZ) and ampicillin. The 23S rRNA gene of isolated strains was amplified and sequenced to identify the mutation site of erythromycin resistance gene, and the seven antigen genotypes of B. pertussis strains (ptxA, ptxC, ptxP, prn, fim2, fim3 and tcfA2) were analyzed. RESULTS: Of the 32 B. pertussis strains, 25 (78%) were resistant to erythromycin, azithromycin, clarithromycin and clindamycin, with an MIC of >256 mg/L, and A2047G mutation was observed in the 23S rRNA gene. All strains had an MIC of ≤0.064 mg/L for SMZ. The MIC of ampicillin, amoxicillin, amoxicillin-clavulanic acid and ceftriaxone ranged from 0.032 to 1 mg/L. The strains resistant to macrolide antibiotics had an antigen genotype of ptxA1/ptxC1/ptxP1/prn1/fim2-1/fim3-1/tcfA2. CONCLUSIONS B. pertussis strains from neonates are often resistant to macrolides, and the in vitro test shows that off-label use of sulfonamides is a reliable regimen for the treatment of neonates with macrolide-resistant pertussis. The prevalence of drug-resistant strains further emphasizes the importance of immunoprophylaxis.
Anti-Bacterial Agents ; Bordetella pertussis ; genetics ; Erythromycin ; Genotype ; Humans ; Infant, Newborn ; Microbial Sensitivity Tests ; Whooping Cough

OBJECTIVE: To investigate the prevalence of Bordetella pertussis infection in children with chronic cough and its clinical features. METHODS: A total of 106 children who were treated at the outpatient service or hospitalized from January 1, 2016 to May 31, 2017 were enrolled. Their nasopharyngeal swabs and venous blood samples were collected for Bordetella pertussis culture, multiple PCR and serum anti-pertussis toxin antibody detection. According to these results, the children were divided into pertussis group with 26 children and control group with 80 children, and clinical features were analyzed for both groups. E-test stripes were used to determine the sensitivity of Bordetella pertussis strains to erythromycin, azithromycin, doxycycline, levofloxacin, sulfamethoxazole/trimethoprim and amoxicillin. RESULTS: Of the 106 children with chronic cough, 26 (24.5%) were found to have Bordetella pertussis infection. There were no significant differences in the incidence rates of typical symptoms of pertussis between the pertussis and control groups (P>0.05). E-test showed that erythromycin and azithromycin had a minimal inhibitory concentration (MIC) of >256 mg/L against five Bordetella pertussis strains, while amoxicillin had an MIC of 0.5-1 mg/L. CONCLUSIONS The presence of Bordetella pertussis infection in children with chronic cough should be taken seriously by clinicians, and children with chronic cough and Bordetella pertussis infection may not have the typical symptoms of pertussis and are mainly manifested as chronic cough. Amoxicillin may be an alternative drug for macrolide-resistant Bordetella pertussis infection.
Azithromycin ; Bordetella pertussis ; Child ; Humans ; Prevalence ; Whooping Cough ; epidemiology

PURPOSE: This report describes the results of a survey of the characteristics of pertussis in children from a single institution and compares it to data from the Korea Centers of Disease Control (KCDC). METHODS: We retrospectively evaluated the medical records of 17 and 6 patients diagnosed with pertussis and parapertussis, respectively, at Soonchunhyang University Bucheon Hospital from January 2005 to January 2017. RESULTS: Of the 17 patients with pertussis, 9 were under 1 year of age (52.9%), 3 were aged between 1 and 10 years (17.6%), and 5 were over 10 years of age (29.4%). Seven patients (41.2%) had never received diphtheria-tetanus-acellular pertussis vaccines, of which 5 were infants below 2 months of age and 2 were 10 years old and lived in China. Four patients showed the initial symptoms of cough in China. The sources of infection were the parents (2 cases) and the siblings (8 cases). All patients showed prolonged severe cough and the average duration of cough was 26 days. Severe symptoms, including dyspnea, cyanosis, apnea, and seizures, were observed in the children under 2 months of age. According to the recent 10-year KCDC data, the highest rate of pertussis diagnosis was noted in infants (47.8%), followed by adolescents (18.7%). Six patients with parapertussis also presented with prolonged severe cough without any other severe symptoms. Lymphocytosis was not found, unlike the patients with pertussis. CONCLUSION: The possibility of pertussis and parapertussis should be considered among patients with prolonged severe cough, especially in infants and adolescents.
Adolescent ; Apnea ; Bordetella parapertussis ; Bordetella pertussis ; Child ; China ; Cough ; Cyanosis ; Diagnosis ; Diphtheria-Tetanus-acellular Pertussis Vaccines ; Dyspnea ; Gyeonggi-do ; Humans ; Infant ; Korea ; Lymphocytosis ; Medical Records ; Parents ; Retrospective Studies ; Seizures ; Siblings ; Whooping Cough

OBJECTIVE: To study the clinical features and risk factors of pertussis in children. METHODS: A retrospective analysis was performed for the clinical data and laboratory markers for immune function of 253 hospitalized children with pertussis. A total of 314 hospitalized children with cough were used as the control group. Quantitative real-time PCR was used to detect Bordetella pertussis DNA. The clinical data of both groups were collected to analyze the risk factors for pertussis. RESULTS: A total of 23 typical clinical parameters were compared between the pertussis and control groups, and there were significant differences in only 10 clinical parameters between the two groups (P<0.01). As for the complications observed in the two groups, the pertussis group had a significantly lower incidence rate of myocarditis than the control group (P<0.05). The pertussis group had significantly lower levels of serum globulin and IgM than the control group (P<0.05). Compared with the control group, the pertussis group had a significantly higher proportion of children with a lack of diphtheria-pertussis-tetanus immunization or timely immunization and a contact history of suspected pertussis patients (P<0.05). A lack of vaccine immunization or timely immunization and a contact history of suspected pertussis patients were risk factors for pertussis (P<0.05). CONCLUSIONS The clinical features are not typical in children with pertussis. Quantitative real-time PCR for detecting Bordetella pertussis DNA helps with the early diagnosis of atypical pertussis. Infants/toddlers should be immunized in time and be isolated from suspected pertussis patients to reduce the incidence of pertussis.
Bordetella pertussis ; Child ; Diphtheria-Tetanus-Pertussis Vaccine ; Humans ; Retrospective Studies ; Risk Factors ; Whooping Cough

Respiratory infections, which are caused by airborne pathogens, are the most common disease of all ages worldwide. This study was conducted to characterize the airborne respiratory pathogens in the public facilities in Busan, South Korea. A total of 260 public facilities were investigated in 2017, 52 seasonal indoor air from 2 hospitals and 208 indoor air samples from 208 randomly selected daycare centers. Among respiratory pathogen, 8 viral pathogens including human adenovirus (HAdV), human bocavirus (HBoV), human rhinovirus (HRV), human parainfluenza virus (HPIV), human respiratory syncytial virus (HRSV), human metapneumovirus (HMPV), human coronavirus (HCoV) and influenza virus (IFV), and 3 bacterial pathogens including Mycoplasma pneumoniae, Bordetella pertussis, and Chlamydophila pneumoniae, were investigated by multiplex real-time reverse transcription polymerase chain reaction. Pathogens were detected in 9 cases (3.4%). Among 9 positive samples, 6 (2.3%) cases were positive for HBoV and 3 (1.2%) cases were positive for IFV. All the positive cases were detected in daycare centers. Additionally, the concentration of HBoV was determined. In HBoV-positive samples, the cycle threshold (Ct) values of HBoV were 29.73~36.84, which are corresponding to the viral concentration of 4.91 × 10⁰ ~ 9.57 × 10² copies/ml. Serotype distribution of isolated HBoV was analyzed by sequencing of VP1/VP2 gene. All of the HBoV isolates were identified as HBoV type 1 with a high similarity among the isolates (>97%). No bacterial pathogen was identified in indoor air samples. Although virus concentration was not high in public facilities (daycare center), the presence of respiratory viral pathogens has been identified. Effective ventilation and air purification strategies are needed to reduce the indoor concentration of respiratory pathogens. A long-term and ongoing surveillance plan for respiratory pathogen management should be established.
Adenoviruses, Human ; Bordetella pertussis ; Busan ; Chlamydial Pneumonia ; Chlamydophila pneumoniae ; Coronavirus ; Human bocavirus ; Humans ; Korea ; Metapneumovirus ; Mycoplasma pneumoniae ; Orthomyxoviridae ; Paramyxoviridae Infections ; Pneumonia, Mycoplasma ; Polymerase Chain Reaction ; Public Facilities* ; Respiratory Syncytial Virus, Human ; Respiratory Tract Infections ; Reverse Transcription ; Rhinovirus ; Seasons ; Serogroup ; Ventilation

In this study, a formulation of Bordetella pertussis proteoliposome (PLBp), diphtheria, and tetanus toxoids and alum (DT-PLBp) was evaluated as a trivalent vaccine candidate in BALB/c mice. Vaccine-induced protection was estimated using the intranasal challenge for pertussis and enzyme-linked immunosorbent assay fvto assess serological responses for diphtheria or tetanus. Both, diphtheria-tetanus-whole cell pertussis (DTP) and diphtheria-tetanus vaccines (DT) were used as controls. Animals immunized with DT-PLBp, PLBp alone, and DTP showed total reduction of CFU in lungs 7 days after intranasal challenge. Likewise, formulations DT-PLBp, DTP, and DT elicited antibody levels ≥2 IU/mL against tetanus and diphtheria, considered protective when neutralization tests are used. Overall, results showed that combination of PLBp with tetanus and diphtheria toxoids did not affect the immunogenicity of each antigen alone.
Animals ; Bordetella pertussis* ; Bordetella* ; Diphtheria Toxoid ; Diphtheria* ; Enzyme-Linked Immunosorbent Assay ; Lung ; Mice* ; Neutralization Tests ; Tetanus Toxoid* ; Tetanus* ; Vaccines ; Whooping Cough