Bordetella pertussis Infection in Infants and Young Children in Shanghai, China, 2016–2017: Clinical Features, Genotype Variations of Antigenic Genes and Macrolides Resistance

Abstract

Pertussis is resurging among infants and young children in Shanghai and household transmission is the main exposure pathway. The high-virulent strains harboring ptxP3/prn2/ptxC2 and the macrolide-resistant Bordetella pertussis strains are quite prevalent. These issues impose a public health concern in Shanghai. Our findings are important to modify the DTaP vaccination strategy and the management guideline of pertussis in China.

High Prevalence of Macrolide-Resistant Bordetella pertussis and ptxP1 Genotype, Mainland China, 2014–2016

“…Because daily movement of the population in Shenzhen, Hong Kong, and Macau is large and has become the regular lifestyle, the ptxP3 strains could be imported more frequently. Shanghai, another economic development area, also had a high proportion of ptxP3 strains ( 14 ). The ptxP3 strains could also be transmitted widely because of less macrolide abuse in southern China.…”

Tracheal colonization factor A (TcfA) is a biomarker for rapid and specific detection of Bordetella pertussis

“…All 170 isolates contained sequences encoding the same protein as the tcfA2 allele, which is reactive with the pertussis LFIA. Broadening our geographic focus, we reviewed 784 other B. pertussis isolates for which TcfA sequence information was available 34,[36][37][38][39][40] . Only 19 of these isolates were from the U.S. 34,39 .…”

“…Only 19 of these isolates were from the U.S. 34,39 . The remaining 765 were from Poland, the Netherlands, China, the United Kingdom, Finland, Sweden, France, Germany, Japan, Italy, and Belgium (listed in descending order based on the number of isolates sourced from each country) 34,[36][37][38][39][40] . These isolates were collected between 1949 and 2017 34,[36][37][38][39][40] .…”

“…The LFIA's inclusivity was further analyzed in silico with sequences from 954 B. pertussis isolates from 12 countries [34][35][36][37][38][39][40] . In sum, of 954 B. pertussis isolates (including 10 tcfA deletion and frameshift mutants identified through a dedicated search for isolates with deficient TcfA expression 39 ), we would predict that the pertussis LFIA would be highly inclusive and would react with 98% of them (i.e.…”

Macrolide-Resistant Bordetella pertussis, Vietnam, 2016−2017

“…Macrolides are commonly used to treat pertussis, but macrolide-resistant B. pertussis (MRBP) strains have been observed in mainland China and Iran (1)(2)(3)(4). In China, MRBP is isolated with increasing frequency (57.5%-91.9%) and has been since the early 2010s (4,5). Most MRBP isolates from China have a homogeneous A2047G mutation in each of the 3 copies of the 23S rRNA gene, which is associated with macrolide resistance (1,3,4).…”