Severe Bordetella pertussis infection and vaccine issue in Chongqing, from 2012 to 2018

Abstract

Objective: Pertussis is a highly contagious respiratory illness mainly caused by the Gram-negative bacterium Bordetella pertussis. The infection of B. pertussis has been increasing and the current diagnosis of pertussis in children is challenging; little is known of B. pertussis infection in Chongqing. Methods: There were 25,441 children (14,863 male and 10,578 female) with suspected pertussis enrolled in our retrospective study from December 2012 to November 2018. Then 800 children with suspected B. pertussis infection were randomly chosen to be evaluated by simultaneous amplification and testing in this prospective study. Results: Infants younger than 12 months had the greatest burden of pertussis, and the incidence of pertussis in Chongqing appeared to have a periodic pattern. The problem of vaccine quality in China was more serious than previously reported based on the fluctuation of infection rates from 2012 to 2018. Simultaneous amplification and testing to detect B. pertussis RNA (Area Under Curve: 0.900 and Kappa value: 0.831) had better diagnostic performance than real-time PCR for B. pertussis DNA (Area Under Curve: 0.869 and Kappa value: 0.690). Conclusions:We revealed the characteristics of B. pertussis infection and vaccine issues in Chongqing. Simultaneous amplification and testing could be a potential novel assay for measuring B. pertussis infection in the future.

The long-term effects of meteorological parameters on pertussis infections in Chongqing, China, 2004–2018

“…Fifth, prior studies reported that new B. pertussis strains different from that included in the present vaccines have emerged 47 , 51 , which may have effect on the manifest rebound of pertussis infections. Sixth, a recent research found that the proportion of the reported pertussis cases aged 1–5 and over 5 years have increased about 4 folds and the proportion aged 3–12 months reduced from 70.59 to 58.39% from 2013 to 2018, respectively, in Chongqing, which can be ascribed to the unqualified vaccine quality 44 , 52 . Finally, weather parameters may also play an important role in the manifest rebound of pertussis infections, as evidenced by the findings of our study and others 14 , 24 – 26 , and it can also be seen from the data in Table S4 that the monthly aggregate precipitation and average wind velocity showed a higher level during the period 2016–2018 as compared to that during the period 2004–2015, while the monthly average air pressure displayed a lower level during the period 2016–2018 relative to the level during the period 2004–2015.…”

“…The exact reasons why the rapid increase in the notified numbers of pertussis in recent years failed to be completely clarified in Chongqing; however, several plausible factors may drive such a rise. First, the use of advanced diagnostic methods with higher sensitivity such as simultaneous amplification and testing (SAT), real-time PCR and serologic has improved the recognition of some mildly or moderately infected individuals, especially for people without typical clinical symptoms 4,44 . Second, the medical professionals have enhanced their awareness of the diagnosis and report of pertussis in that this disease was designated as a notifiable infectious disease in China 3,12 .…”

“…According to the immunization schedule of pertussis in China 11 , it appeared that this situation accounted well for the increased numbers in adolescents and adults in temporality over the last years 44 . Fourth, previous publication has found that young infants accounted for the large proportion of the infected people in Chongqing 12,44 , this may be due to the fact that most young infants at the year of below 3 months were not vaccinated the DTwP vaccination, and the rapid decay of the antibodies to pertussis toxin (PT) and filamentous haemagglutinin (FHA) in infant sera derived from their mothers make infants susceptible to B. pertussis 49,50 . Fifth, prior studies reported that new B. pertussis strains different from that included in the present vaccines have emerged 47,51 , which may have effect on the manifest rebound of pertussis infections.…”

“…It has been demonstrated that there is a protective effect of pertussis vaccine during the period of around 4–12 years 47 , 48 . According to the immunization schedule of pertussis in China 11 , it appeared that this situation accounted well for the increased numbers in adolescents and adults in temporality over the last years 44 . Fourth, previous publication has found that young infants accounted for the large proportion of the infected people in Chongqing 12 , 44 , this may be due to the fact that most young infants at the year of below 3 months were not vaccinated the DTwP vaccination, and the rapid decay of the antibodies to pertussis toxin (PT) and filamentous haemagglutinin (FHA) in infant sera derived from their mothers make infants susceptible to B. pertussis 49 , 50 .…”

Exosome-Based Vaccines: History, Current State, and Clinical Trials

“…However, exosomes and OMVs derived from bacteria have been reported to be potent immune modulators, rather than aiding pathogenesis (163). The potential of OMVs as immune activators has been investigated using models of different infectious diseases such as pertussis (whooping cough), which is caused by Bordetella pertussis, a gram-negative bacterium (164). Currently available vaccines aid the successful reduction of the morbidity and mortality caused by pertussis, but they are also associated with severe adverse effects and weak immune protection (165).…”