<sec>
<title>Objectives</title>
<p>The purpose of the current study was to determine the upper threshold number of cases for which pertussis infection would reach an outbreak level nationally in Iran.</p></sec>
<sec>
<title>Methods</title>
<p>Data on suspected cases of pertussis from the 25<sup>th</sup> February 2012 to the 23<sup>rd</sup> March 2018 from the Center for Disease Control and Prevention in Iran was used. The national upper threshold level was estimated using the exponentially weighted moving average (EWMA) method and the Poisson regression method.</p></sec>
<sec>
<title>Results</title>
<p>In total, 2,577 (33.6%) and 1,714 (22.3%) cases were reported in the Spring and Summer respectively. There were 1,417 (18.5%) and 1,971 (25.6%) cases reported in the Autumn and Winter, respectively. The overall upper threshold using the EWMA and the Poisson regression methods, was estimated as a daily occurrence of 8 (7.55) and 7.50 (4.48–11.06) suspected cases per 10,000,000 people, respectively. The daily seasonal thresholds estimated by the EWMA and the Poisson regression methods were 10, 7, 6, 8 cases and 10, 7, 7, 9 cases for the Spring, Summer, Autumn, and Winter, respectively.</p></sec>
<sec>
<title>Conclusion</title>
<p>The overall and seasonal estimated thresholds by the 2 methods were similar. Therefore, the estimated thresholds of 6–10 cases in a day, per 10,000,000 people could be used to detect pertussis outbreaks and epidemics by health policymakers.</p></sec>
Citations
Citations to this article as recorded by
Burden of pertussis in infants in the Eastern Mediterranean Region and the impact of maternal vaccination: a systematic review Randa K. Saad, Yousef Khader, Flor M. Munoz, Faris Lami, Ezzeddine Mohsni, Nadine Haddad BMC Public Health.2025;[Epub] CrossRef
Pertussis resurgence in iran: A systematic review and meta-analysis of seroimmunity and diagnostic evidence Parvaneh Sadeghimoghadam, Reza Sattarpour, Maryam Noori, Nasim Sattarpour, Ali Afkhaminia, Zeinab Sinaeifar, Amir Naddaf, Zahra Omidi BMC Infectious Diseases.2025;[Epub] CrossRef
Immunogenicity and Safety of a Newly Developed Tetanus-Diphtheria Toxoid (Td) in Healthy Korean Adolescents: a Multi-center, Randomized, Double-blind, Active-Controlled Phase 3 Trial Ui Yoon Choi, Ki Hwan Kim, Jin Lee, Byung Wook Eun, Hwang Min Kim, Kyung-Yil Lee, Dong Ho Kim, Sang Hyuk Ma, Jina Lee, Jong-Hyun Kim Journal of Korean Medical Science.2021;[Epub] CrossRef
Objectives
During recent decades, there has been limited attention on the seasonal pattern of pertussis within a high vaccine coverage population. This study aimed to compare the seasonal patterns of clinical suspected pertussis cases with those of laboratory confirmed cases in Iran. Methods
The current study was conducted using time series methods. Time variables included months and seasons during 2011–2013. The effects of seasons and months on the incidence of pertussis were estimated using analysis of variance or Kruskal–Wallis. Results
The maximum average incidence of clinically confirmed pertussis was 23.3 in July (<i>p</i> = 0.04), but the maximum incidence of clinical suspected pertussis was 115.7 in May (<i>p</i> = 0.6). The maximum seasonal incidences of confirmed and clinical pertussis cases were reported in summer (average: 12, <i>p</i> = 0.004), and winter (average: 108.1; <i>p</i> = 0.4), respectively. Conclusion
The present study showed that the seasonal pattern of laboratory confirmed pertussis cases is highly definite and different from the pattern of clinical suspected cases.
Citations
Citations to this article as recorded by
Epidemiology of respiratory infections and their association with air pollution and meteorological factors in China, 2004-2018 Muli Zhang, Liping Zhao, Xiaoming Liu, Xiaolong Xu, Fangchao Liu, Jia-Hong Tang, Wenyu Jing, Jinfeng Yin, Yuan Yuan, Kehan Wang, Na Zhao, Hong-Lian Jian, Weimin Li, Shelan Liu, Hui Jiang, Ta-Chien Chan Hygiene and Environmental Health Advances.2026; 18: 100180. CrossRef
Seroepidemiological Assessment of Bordetella pertussis in Jahrom, Southern Iran: A Cross‐Sectional Study Rahim Raufi, Fatemeh Zareian‐Jahromi, Saba Zangeneh, Jalil Rajabi, Reza Shahriarirad Health Care Science.2025; 4(1): 44. CrossRef
Ergodic stationary distribution and extinction of stochastic pertussis model with immune and Markov switching Jia Chen, Yuming Chen, Qimin Zhang Electronic Research Archive.2025; 33(5): 2736. CrossRef
Resurgence of Pertussis in the Autonomous Province of Vojvodina, Serbia: Shifting Seasonality, Age Patterns, and the Need for Booster Immunization Mioljub Ristić, Vladimir Vuković, Smiljana Rajčević, Snežana Medić, Marko Koprivica, Vladimir Petrović Vaccines.2025; 13(8): 814. CrossRef
Pertussis resurgence in iran: A systematic review and meta-analysis of seroimmunity and diagnostic evidence Parvaneh Sadeghimoghadam, Reza Sattarpour, Maryam Noori, Nasim Sattarpour, Ali Afkhaminia, Zeinab Sinaeifar, Amir Naddaf, Zahra Omidi BMC Infectious Diseases.2025;[Epub] CrossRef
Pertussis seasonal variation in Northern Vietnam: the evidence from a tertiary hospital Nhung TH Pham, Quyen TT Bui, Dien M Tran, Mattias Larsson, Mai P Pham, Linus Olson BMC Public Health.2024;[Epub] CrossRef
Population-Based Study of Pertussis Incidence and Risk Factors among Persons >50 Years of Age, Australia Rodney Pearce, Jing Chen, Ken L. Chin, Adrienne Guignard, Leah-Anne Latorre, C. Raina MacIntyre, Brittany Schoeninger, Sumitra Shantakumar Emerging Infectious Diseases.2024;[Epub] CrossRef
Bordetella pertussis in School-Age Children, Adolescents, and Adults: A Systematic Review of Epidemiology, Burden, and Mortality in the Middle East Denis Macina, Keith E. Evans Infectious Diseases and Therapy.2021; 10(2): 719. CrossRef
Pertussis epidemiology and effect of vaccination among diagnosed children at Vietnam, 2015‐2018 Nhung T. H. Pham, Nhan D. T. Le, Ngai K. Le, Khoa D. Nguyen, Mattias Larsson, Linus Olson, Dien M. Tran Acta Paediatrica.2020; 109(12): 2685. CrossRef
Spatial distribution of vaccine-preventable diseases in central Iran in 2015–2018: A GIS-based study Abolfazl Mohammadbeigi, Abedin Saghafipour, Nahid Jesri, Fatemeh Zahra Tarkhan, Moharram Karami Jooshin Heliyon.2020; 6(9): e05102. CrossRef
The comparative performance of wavelet‐based outbreak detector, exponential weighted moving average, and Poisson regression‐based methods in detection of pertussis outbreaks in Iranian infants: A simulation‐based study Yousef Alimohamadi, Seyed Mohsen Zahraei, Manoochehr Karami, Mehdi Yaseri, Mojtaba Lotfizad, Kourosh Holakouie‐Naieni Pediatric Pulmonology.2020; 55(12): 3497. CrossRef
Alarm Thresholds for Pertussis Outbreaks in Iran: National Data Analysis Yousef Alimohamadi, Seyed Mohsen Zahraei, Manoochehr Karami, Mehdi Yaseri, Mojtaba Lotfizad, Kourosh Holakouie-Naieni Osong Public Health and Research Perspectives.2020; 11(5): 309. CrossRef
The burden of laboratory-confirmed pertussis in low- and middle-income countries since the inception of the Expanded Programme on Immunisation (EPI) in 1974: a systematic review and meta-analysis Rudzani Muloiwa, Benjamin M. Kagina, Mark E. Engel, Gregory D. Hussey BMC Medicine.2020;[Epub] CrossRef
Sommergrippe: Mehr als ein Mythos! Johannes Bogner MMW - Fortschritte der Medizin.2019; 161(12): 39. CrossRef
Estimating seasonal variation in Australian pertussis notifications from 1991 to 2016: evidence of spring to summer peaks R. N. F. Leong, J. G. Wood, R. M. Turner, A. T. Newall Epidemiology and Infection.2019;[Epub] CrossRef
Time series modeling of pertussis incidence in China from 2004 to 2018 with a novel wavelet based SARIMA-NAR hybrid model Yongbin Wang, Chunjie Xu, Zhende Wang, Shengkui Zhang, Ying Zhu, Juxiang Yuan, Lei Lin PLOS ONE.2018; 13(12): e0208404. CrossRef
Identification of Etiologic Agents of the Pertussis-like Syndrome in Children by Real-time PCR Method Shima Mahmoudi, Maryam Banar, Babak Pourakbari, Hediyeh Sadat Alavi, Hamid Eshaghi, Alireza Aziz Ahari, Setareh Mamishi Prague Medical Report.2018; 119(1): 61. CrossRef
Objectives
To confirm genotype diversities of clinical isolates of <i>Bordetella pertussis</i> and to evaluate the risk of pertussis outbreak in Korea. Methods
Seven housekeeping genes and 10 antigenic determinant genes from clinical <i>B. pertussis</i> isolates were analyzed by Multilocus sequence typing (MLST). Results
More variant pattern was observed in antigenic determinant genes. Especially, <i>PtxS1</i> gene was the most variant gene; five genotypes were observed from eight global genotypes. In the bacterial type, the number of observed sequence types in the isolates was seven and the most frequent form was type 1 (79.6%). This major sequence type also showed a time-dependent transition pattern. Older isolates (1968 and 1975) showed type 1 and 6 in housekeeping genes and antigenic determinant genes, respectively. However, these were changed to type 2 and 1 in isolates 1999–2008. This transition was mainly attributed to genotype change of <i>PtxS1</i> and <i>Fim3</i> gene; the tendency of genotype change was to avoid vaccine-derived genotype. In addition, there was second transition in 2009. In this period, only the sequence type of antigenic determinant genes was changed to type 2. Based Upon Related Sequence Types (BURST) analysis confirmed that there were two clonal complexes (ACCI and ACCII) in the Korean isolates. Moreover, the recently increased sequence type was revealed as AST2 derived from AST 3 in ACCI. Conclusions
Genotype changes in Korean distributing strains are still progressing and there was a specific driving force in antigenic determinant genes. Therefore continuous surveillance of genotype change of the distributing strains should be performed to confirm interrelationship of genotype change with vaccine immunity.
Citations
Citations to this article as recorded by
Pertussis in the Post-COVID-19 Era: Resurgence, Diagnosis, and Management Hyun Mi Kang, Taek-Jin Lee, Su Eun Park, Soo-Han Choi Infection & Chemotherapy.2025; 57(1): 13. CrossRef
Characterization of Bordetella pertussis Strains Isolated from India Shweta Alai, Manish Gautam, Sonali Palkar, Jitendra Oswal, Sunil Gairola, Dhiraj P. Dhotre Pathogens.2022; 11(7): 794. CrossRef
Variation in Bordetella pertussis Susceptibility to Erythromycin and Virulence-Related Genotype Changes in China (1970-2014) Ying Yang, Kaihu Yao, Xiang Ma, Wei Shi, Lin Yuan, Yonghong Yang, Daniela Flavia Hozbor PLOS ONE.2015; 10(9): e0138941. CrossRef
Recent Trends of Antigenic Variation inBordetella pertussisIsolates in Korea So-Hyun Kim, Jin Lee, Hwa Young Sung, Jae Yon Yu, Seong Han Kim, Mi Sun Park, Sang-Oun Jung Journal of Korean Medical Science.2014; 29(3): 328. CrossRef
First
Prev
