Page 257 - TBE_Book_V2_2019

Chapter 12b

TBE in China

Yang Junfeng and Heinz-Josef Schmitt

History and Current Situation

The first TBE patients in China were reported and this is different from previous reports
in 1943, and the TBEV was isolated from the where soldiers and forest workers made up
brain tissues of 2 patients in 1944 by the majority of patients.
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Japanese military scientists, and from
patients and ticks (Ixodes persulcatus and Patients also were reported from another
Haemaphysalis concinna) in 1952 by Chinese important epidemic area: the Tianshan
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researchers. The Far Eastern viral subtype Mountains and Altai Mountains of the
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(TBEV-FE) is the endemic subtype that has Xinjiang Autonomous Region.
been isolated from all 3 known natural foci
(northeastern China, western China, and Despite the small geographic distribution, the
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southwestern China). Recently a new whole belt that connects the 3 above-
“Himalayan subtype” of the TBEV (TBEV-HIM) mentioned foci is considered to be at risk for
was isolated from wild rodent Marmoata occurrence of TBE if the virus is imported,
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himalayana in the Qinghai-Tibet Plateau. including a few densely populated regions
The main vector of the TBEV in China is I. such as Beijing, Shaanxi, and Sichuan
3 provinces, where the environment could be
persulcatus. One recent report suggests that
the TBEV-SIB is prevalent in the Uygur region suitable for circulation of TBEV (see map
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(North West China) but epidemiological below). In addition, cases may be missed in
regions with lower TBE incidences due to a
modelling indicates that the TBEV may occur
4
even widely all over China (Figure 3). lack of awareness and low rates of serological
Furthermore, likely the disease is often testing among both physicians and the
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missed by clinicians due to a lack of the general population.
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availability of specific diagnostic assays.
The incidence of TBE decreased in China
during the 1980s, but has been rising in
Serological research has demonstrated that
there have been human infections with TBEV recent years, as noted by disease control and
4
among these 3 foci. However, TBE patients prevention authorities and local hospitals.
were mainly reported from the epicenter in TBE patients were mainly forest workers
before the 1980s, however, it has been
northeastern China, including Inner Mongolia
Autonomous Region (Daxing’an Mountains), reported that changes in the occupation /
Heilongjiang Province (Xiaoxing’an type of “exposure risk” occurred among TBE
Mountains), and Jilin Province (Changbai patients since the 1980s and in particular
Mountains). In a recent report 803 cases since the late 1990s, with 70–95% of the
most recent patients being non-forest
including 4 deaths were reported from the
Jilin Province with most cases from the working farmers, housewives, domestic
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Changbai Mountains and neighboring areas. workers, students, or anyone with any
Interestingly 61.5% of patients were farmers occupation who entered endemic forest
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areas.

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