A family cluster of infections by a newly recognized bunyavirus in eastern China, 2007: further evidence of person-to-person transmission.
BACKGROUND
Seven persons in one family living in eastern China developed fever and thrombocytopenia during May 2007, but the initial investigation failed to identify an infectious etiology. In December 2009, a novel bunyavirus (designated severe fever with thrombocytopenia syndrome bunyavirus [SFTSV]) was identified as the cause of illness in patients with similar clinical manifestations in China. We reexamined this family cluster for SFTSV infection.


METHODS
We analyzed epidemiological and clinical data for the index patient and 6 secondary patients. We tested stored blood specimens from the 6 secondary patients using real time reverse transcription polymerase chain reaction (RT-PCR), viral culture, genetic sequencing, micro-neutralization assay (MNA), and indirect immunofluorescence assay (IFA).


RESULTS
An 80-year-old woman with fever, leucopenia, and thrombocytopenia died on 27 April 2007. Between 3 and 7 May 2007, another 6 patients from her family were admitted to a local county hospital with fever and other similar symptoms. Serum specimens collected in 2007 from these 6 patients were positive for SFTS viral RNA through RT-PCR and for antibody to SFTSV through MNA and IFA. SFTSV was isolated from 1 preserved serum specimen. The only shared characteristic between secondary patients was personal contact with the index patient; none reported exposure to suspected animals or vectors.


CONCLUSIONS
Clinical and laboratory evidence confirmed that the patients of fever and thrombocytopenia occurring in a family cluster in eastern China in 2007 were caused by a newly recognized bunyavirus, SFTSV. Epidemiological investigation strongly suggests that infection of secondary patients was transmitted to family members by personal contact.
Department of Acute Infectious Diseases Control and Prevention, Jiangsu Provincial Centre for Disease Control and Prevention, Nanjing, China.
Chang-jun
CJ
Bao
Xi-ling
XL
Guo
Xian
X
Qi
Jian-li
JL
Hu
Ming-hao
MH
Zhou
Jay K
JK
Varma
Lun-biao
LB
Cui
Hai-tao
HT
Yang
Yong-jun
YJ
Jiao
John D
JD
Klena
Lu-xun
LX
Li
Wen-yuan
WY
Tao
Xian
X
Li
Yin
Y
Chen
Zheng
Z
Zhu
Ke
K
Xu
Ai-hua
AH
Shen
Tao
T
Wu
Hai-yan
HY
Peng
Zhi-feng
ZF
Li
Jun
J
Shan
Zhi-yang
ZY
Shi
Hua
H
Wang
D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000097:blood; D002044:Bunyaviridae Infections / Q000453:epidemiology* / Q000635:transmission*; D002681:China / Q000453:epidemiology; D016000:Cluster Analysis; D005192:Family Health; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D016851:Orthobunyavirus / Q000302:isolation & purification*; D012367:RNA, Viral / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D014776:Virus Cultivation
D000914:Antibodies, Viral; D012367:RNA, Viral