In recent years, the incidence rate of pertussis in China has been steadily increasing, presenting an increasingly severe challenge for disease prevention and control. To strengthen the immune barrier in the population and effectively curb the spread of pertussis, National Disease Control and Prevention Administration of China and other relevant authorities optimized the immunization procedure for diphtheria-tetanus-pertussis vaccine, with the new procedure implemented in 2025. This adjustment includes three key measures: advancing the initial dose of the vaccine from 3 months to 2 months of age, extending the interval between primary immunization doses from 1 month to 2 months, and adding an extra dose of acellular diphtheria-tetanus-pertussis vaccine at 6 years of age. This article discusses potential changes in the epidemiology and clinical manifestations of pertussis following such adjustments for immunization procedure, and awareness of these changes will facilitate the accurate identification of pertussis cases, which is crucial for evaluating the impact of these adjustments and further optimizing immunization strategies.
Humans ; Whooping Cough/epidemiology* ; Diphtheria-Tetanus-Pertussis Vaccine/immunology* ; Infant ; Immunization Schedule ; Child

Some countries with high coverage of diphtheria, tetanus and pertussis combined vaccines have experienced pertussis epidemics and/or local outbreaks since 1980s. This phenomenon is called "pertussis resurgence". In recent years, pertussis epidemics in several provinces of China have resurged dramatically, arousing great concern from all parties. By referring the working model of the Global Pertussis Initiative, the Chinese Preventive Medicine Association has organized and launched the China Pertussis Initiative. A group of experts in this field has analyzed data of current pertussis in China and identified problems posed by the disease. This expert consensus was completed based on the discussions of the latest national and international research progeress, epidemiological trends and immunization strategies of pertussis, with special aims to provide guidance for the surveillance, prevention and control of pertussis in China.
China/epidemiology* ; Consensus ; Humans ; Immunization, Secondary ; Tetanus ; Vaccination ; Whooping Cough/prevention & control*

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

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.
China ; epidemiology ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Pertussis Vaccine ; immunology ; Risk Factors ; Whooping Cough ; epidemiology ; prevention & control ; transmission

PURPOSE: Pertussis can be prevented with a vaccine. Despite this, there have been an increasing number of cases worldwide, and also in Korea. This study aimed to investigate the epidemiology and clinical characteristics of the recent outbreak in the Changwon area. METHODS: Patients who visited Changwon Fatima Hospital from July 2015 to March 2016 with respiratory symptoms, including spasmodic cough, cough induced vomiting, inspiratory ‘intake’ sound (whooping), and a night-time cough for >1 week were included in this study. Respiratory specimens were collected from patients and a polymerase chain reaction (PCR) and detected anti-pertussis immunoglobulin G enzyme-linked immunosorbent assay kit test were performed. Patients with underlying diseases, or those who had received a DTaP or Tdap vaccination in recent 1 year were excluded. RESULTS: Pertussis was diagnosed in 37 of 50 patients, two patients were positive according to the PCR, and 37 patients were positive according to serologic tests. The age distribution of the patients was 1 month to 15 years. After administering antibiotics, all patients recovered without complications. CONCLUSIONS: A pertussis outbreak occurred in Changwon in 2015 and 2016. This data can provide the basis for further study on the epidemiology of pertussis in Korea.
Age Distribution ; Anti-Bacterial Agents ; Cough ; Enzyme-Linked Immunosorbent Assay ; Epidemiology ; Gyeongsangnam-do* ; Humans ; Immunoglobulin G ; Korea ; Polymerase Chain Reaction ; Serologic Tests ; Vaccination ; Vomiting ; Whooping Cough*

Although tetanus and diphtheria have become rare in developed countries, pertussis is still endemic in some developed countries. These are vaccine-preventable diseases and vaccination for adults is important to prevent the outbreak of disease. Strategies for tetanus, diphtheria, and pertussis vaccines vary from country to country. Each country needs to monitor consistently epidemiology of the diseases and changes vaccination policies accordingly. Recent studies showed that tetanus–diphtheria–acellular pertussis vaccine for adults is effective and safe to prevent pertussis disease in infants. However, vaccine coverage still remains low than expected and seroprevalence of protective antibodies levels for tetanus, diphtheria, and pertussis decline with aging. The importance of tetanus–diphtheria–acellular pertussis vaccine administration should be emphasized for the protection of young adult and elderly people also, not limited to children.
Adult* ; Aged ; Aging ; Antibodies ; Child ; Developed Countries ; Diphtheria ; Diphtheria-Tetanus-acellular Pertussis Vaccines ; Epidemiology ; Humans ; Infant ; Pertussis Vaccine ; Seroepidemiologic Studies ; Tetanus ; Vaccination* ; Vaccines ; Whooping Cough* ; Young Adult

We investigated the prevalence of pertussis in Korean adolescents and adults with persistent cough. Study population was adolescents (aged 11-20 yr) and adults (> or = 21 yr old) who showed persistent cough of 1-8 weeks' duration. Pertussis was diagnosed by culture, polymerase chain reaction (PCR), and serology. A total of 310 subjects participated in this study, and 76 cases (24.5%) met the criteria for laboratory-confirmed pertussis. The majority of the pertussis cases (66/76) were confirmed by serology, while 3 cases (1.0%) were diagnosed with culture, and 10 cases (3.2%) were detected with PCR. Of the 76 subjects diagnosed with pertussis, 20/86 cases were adolescents and 56/224 cases were adults. Neither adolescents nor adults received adolescent-adult booster against pertussis within the previous 5 yr. Pertussis can be a primary cause of persistent cough in Korean adolescents and adults.
Adolescent ; Adult ; Bordetella pertussis/immunology ; Child ; Cough/*epidemiology ; Diphtheria-Tetanus-Pertussis Vaccine/immunology/*therapeutic use ; Female ; Humans ; Immunization, Secondary/*utilization ; Male ; Republic of Korea/epidemiology ; Whooping Cough/*epidemiology/immunology ; Young Adult

PURPOSE: The adult tetanus, reduced diphtheria, and acellular pertussis (Tdap) vaccine has been introduced in order to provide individual protection and reduce the risk of transmitting pertussis to infants. We assessed the knowledge and acceptability of the Tdap vaccine around pregnancy. MATERIALS AND METHODS: This study was a cross-sectional survey of women of childbearing age (20-45 years) who visited obstetrics and gynecologic units of primary, secondary, or tertiary hospitals. They were asked to fill in a questionnaire assessing their knowledge, attitudes, and acceptability of Tdap. RESULTS: The questionnaire was completed by 308 women; 293 (95.1%) had not received information from doctors about Tdap, and 250 (81.2%) did not know about the need for vaccination. A significantly important factor related to subjects' intention to be vaccinated, identified by stepwise multiple logistic regression, was the knowledge (OR 13.5, CI 3.92-46.33) that adult Tdap is effective in preventing pertussis for infants aged 0-6 months. Additionally, 276 (89.6%) considered the recommendation of obstetric doctors as the most influencing factor about Tdap vaccination. CONCLUSION: In Korea, most women of childbearing age seem to be neither recommended nor adequately informed about the vaccination, although our population was not a nationwide representative sample. Information given by healthcare workers may be critical for improving awareness and preventing pertussis.
Adult ; Cross-Sectional Studies ; Diphtheria ; Diphtheria-Tetanus-acellular Pertussis Vaccines/*administration & dosage ; Female ; Health Knowledge, Attitudes, Practice/*ethnology ; Humans ; Immunization/*statistics & numerical data ; Infant ; Logistic Models ; Multivariate Analysis ; Patient Acceptance of Health Care/*ethnology/statistics & numerical data ; Pregnancy ; Republic of Korea/epidemiology ; Risk ; Surveys and Questionnaires ; Tetanus ; Vaccination ; Whooping Cough/diagnosis/ethnology

OBJECTIVETo summarize the clinical characteristics of whooping cough in children and analyze the risk factors for severe whooping cough.

METHODA retrospective analysis was made on the clinical data of 247 children with whooping cough in Children's Hospital of Chongqing Medical University between Jan 2013 and Dec 2014. Of these patients, 126 were male, 121 were female, the median age was 3.1 months (23 days-4 years and eight months old). The patients were divided into two groups, group 1 had infants less than 3 months of age (n=120) and group 2 had infants and young children older than 3 months (n=127) according to their age. On the other hand, the patients were also divided into two groups according to vaccination status: vaccinated group (received diphtheria toxoid, tetanus toxoid, and acellular pertussis, DTP) (n=31) and unvaccinated group (n=188). Pure Bordetella pertussis infection was seen in 106 cases, and 141 cases had mixed infection. Severe disease was seen in 13 cases, and the other 234 cases had the modest disease. Clinical data were retrospectively analyzed and compared.

RESULT(1) Bordetella pertussis was identified in 57/680 cases (8.4%) in 2013, and 190/1 856 cases (10.2%) in 2014. The disease could be seen throughout the year, but 182 cases (73.7%) occurred in summer or autumn; 202 cases (81.8%) were less than 6 months. (2) Paroxysmal cough was seen in 238 cases (96.4%) , 61 cases (24.7%) had inspiratory whoop. Infants in group 1 often had episodes of cyanosis, apnea and suffocation (χ² = 19.999, 12.081, 6.508, P<0.05), persistent cough was often seen in group 2 (χ² = 9.885, P<0.05). Complications such as severe pneumonia, pulmonary consolidation and encephalopathy were more common in the group 1 than in group 2 (χ² = 17.340, 6.080, 11.030, 23.545, P<0.05). (3) The length of stay of group 1, and of unvaccinated group was significantly longer than that of group 2 and of vaccinated group (t=19.331, 26.741, P<0.05). (4) Leukocytosis was found in 224 cases (90.7%), 182 cases (73.7%) had predominant lymphocytosis. White blood cell in group 1, unvaccinated group and severe disease group was higher than the corresponding group (t=11.075,13.739,3.469, P<0.05). (5) Patients who had a history of exposure, fever, leukocytosis and pulmonary consolidation or atelectasis on chest imaging were prone to develop into severe pertussis (OR=4.521, 4.900, 1.085, 4.792, 50.400; P<0.05). A total of 244 cases (98.8%) recovered, 3 cases (1.2%) died, they were less than 3 months old and unvaccinated.

CONCLUSIONThe number of cases with whooping cough in Chongqing area tends to be rising. The disease occurred mostly in summer and fall. Infants less than 3 months old, unvaccinated with DTP had high susceptibility to pertussis, often had a severe clinical presentation and severe complications, had a high mortality rate.

Bordetella pertussis ; Brain Diseases ; Child, Preschool ; China ; epidemiology ; Cough ; Cyanosis ; Female ; Fever ; Hospitals, Pediatric ; Humans ; Infant ; Infant, Newborn ; Leukocytes ; Lymphocytosis ; Male ; Pulmonary Atelectasis ; Retrospective Studies ; Risk Factors ; Seasons ; Vaccination ; statistics & numerical data ; Whooping Cough ; epidemiology

This study was conducted to evaluate age-specific seroprevalence of pertussis in Korea and to formulate a strategy to prevent and reduce the incidence of pertussis. Residual serum samples of healthy adolescents and adults 11 yr of age or older were collected between July 2012 and December 2012, and anti-pertussis toxin (PT) IgG titers were measured using a commercial ELISA kit. We compared the mean anti-PT IgG titers and seroprevalence of pertussis of the six age groups: 11-20, 21-30, 31-40, 41-50, 51-60, and > or = 61 yr. A total of 1,192 subjects were enrolled. The mean anti-PT IgG titer and pertussis seroprevalence were 35.53 +/- 62.91 EU/mL and 41.4%, respectively. The mean anti-PT IgG titers and seroprevalence were not significantly different between the age groups. However, the seroprevalence in individuals 51 yr of age or older was significantly higher than in individuals younger than 51 yr (46.5% vs 39.1%, P = 0.017). Based on these results, a new pertussis prevention strategy is necessary for older adults.
Adolescent ; Adult ; Aging ; Antibodies, Bacterial/*blood ; Bordetella pertussis/*immunology ; Child ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Immunoglobulin G/*blood/immunology ; Incidence ; Male ; Middle Aged ; Pertussis Toxin/blood/*immunology ; Pertussis Vaccine/immunology ; Republic of Korea/epidemiology ; Seroepidemiologic Studies ; Vaccination ; Whooping Cough/blood/*epidemiology ; Young Adult