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Journal of Infectious Diseases and Treatment
ISSN: 2472-1093
7
t h
E u r o s c i c o n C o n f e r e n c e o n
Clinical Pathology
and Epidemiology
F e b r u a r y 2 7 - 2 8 , 2 0 1 9
P r a g u e , C z e c h R e p u b l i c
Clinical Pathology & Epidemiology 2019
S
ince 2011, epidemics of scarlet fever have resurged in several countries, including China, where
emm
12 group A
Streptococcus
(GAS) was responsible for the 2011 large outbreaks. Afterwards, scarlet fever outbreak occurred annually. To date, factors
driving the outbreaks have not been well elucidated. Epidemiological data of scarlet fever in Shanghai during 2011-2015 were
obtained from the National Notifiable Infectious Disease Surveillance System. Throat swabs of patients with scarlet fever from
the Sentinel Hospital, from which 50% of scarlet fever cases in Shanghai were reported, were cultured. GAS carriage surveillance
was performed in schools located in three districts. A total of 1,568 GAS isolates were collected for analysis, including 1,451
isolates from patients and 117 from carriers. This continuous study showed that the annual incidence of culture-confirmed
scarlet fever was 7.5-19.4/100,000-person-year in Shanghai during 2011-2015, with an average GAS carriage rate being 7.6%
in school-aged children. Twelve
emm
types were identified with co-predominance of emm12 (61.8%) and emm1 (35.9%), which
harboured different super-antigen profiles. The proportion of emm1 GAS strains increased from 3.8% in 2011 to 48.6% in 2014.
Two predominant clones identified by pulsed-field gel electrophoresis, SH001-
emm
12 and SH002-
emm
1, were discovered in
66.9% of scarlet fever cases and 50% of carriers, respectively. The frequencies of resistance to macrolides and tetracycline
among GAS isolates were both over 95%, which was mediated by ermB and tetM, respectively. GAS population is changing, and
ongoing surveillance is warranted to monitor the dynamic changes of GAS emm type, predominant clone, and superantigen
profile.
cmlbright@126.comClonal dissemination of
emm
12 and
emm
1 group
A
Streptococcus
strains causing scarlet fever
during 2011-2015 in Shanghai, China
Mingliang Chen
1, 4
, Jiehao Cai
2
, Mark R Davies
3
, Yuefang Li
2
, Chi
Zhang
1
, Weilei Yao
2
, Dechuan Kong
1
, Hao Pan
1
, Xi Zhang
1
, Min
Chen
1
and Mei Zeng
2
1
Shanghai Municipal Center for Disease Control and Prevention, China
2
Children's Hospital of Fudan University, China
3
The Peter Doherty Institute for Infection and Immunity-University of Melbourne, Australia
4
Shanghai Institutes of Preventive Medicine, China
J Infec Dis Treat 2019, Volume: 5
DOI: 10.21767/2472-1093-C1-009