Influenza Virus: Lab, Treatment and Prevention在线视频

Lab diagnosis, treatment and prevention
实验室诊断，治疗和预防

Do you still remember the girl?
还记得那个女孩吗？

If we want to confirm
如果要确诊

our diagnosis as flu,
流感，

we need to do some laboratory tests.
我们需要做实验室检查

What we can do,
能做的是

1, isolation and identification
1.分离并鉴定

of virus.
病毒

The samples can be nasal washings,
样本可来自于鼻腔灌洗液，

gargles and throat swabs.
咽、喉拭子

Rapid techniques detect and identify
通过ELISA或者RT-PCR

the influenza antigens or genome
快速检测流感病毒抗原

of the virus by ELISA or RT-PCR.
和基因组

The virus also can be isolated
病毒也可以通过培养

by culture.
分离

The embryonated eggs could be used
鸡胚可以被用于

to isolate the flu virus.
分离流感病毒

The amniotic or allantoic
羊膜腔或尿囊腔接种

inoculations are common.
比较常见

The culture fluid is examined for virus
培养7天后的上清液可以

after 7 days by hemagglutination test.
采用血凝试验检测病毒

Hemagglutination test is used
血凝试验用于

to identify the viruses.
鉴定病毒

Cell culture also could be used.
细胞培养也可以用于鉴定病毒

The cells are examined
红细胞吸附试验可用于

by hemadsorption test.
检查被病毒感染的细胞

We can see from this photo,
从这张图片我们可以看到

the viral infected cell expresses
被病毒感染的细胞

viral HA on the surface,
可以在细胞表面表达病毒的血凝素

then can adhere to RBCs.
然后吸附红细胞

Hemagglutination and hemadsorption
血凝试验和红细胞吸附试验

are not specific for influenza viruses;
都不是特异性检测流感病毒的方法

parainfluenza viruses and other viruses
副流感病毒和其他的病毒

also have these properties.
也有相同的特点

Besides the isolation
除了分离和鉴定

and identification of the virus,
病毒

the serologic test is also helpful
血清学试验

for the diagnosis.
对诊断也会很有帮助

Samples are paired serum specimens.
样本为急性期和恢复期的血清标本

HI (hemagglutination inhibition ) test：
血凝抑制试验

4-fold increase is of diagnostic value.
血清样本滴度的4倍增强具有诊断价值

Again,

the hemagglutination inhibition
血凝抑制试验

test (HI) is used to detect
用于检测

the antibodies in serum.
血清中的抗体

Pathogenicity of flu virus.
流感病毒的致病性

Source of infection is
传染源是

patients & asymptomatic carriers.
患者或者无症状携带者

Route of transmission is
传播途径是

respiratory route.
呼吸道

Season: usually in winter and spring.
多发季节：通常是冬春季

Disease is influenza.
所致疾病是流感

Sneezing can spread the flu virus
打喷嚏会把流感病毒

to other people.
传播给其他人

Time course
甲型流感病毒

of influenza A viral infection.
感染的过程

The classic "flu syndrome" occurs early.
患者早期出现典型的“流感症状”

Later,
随后，

pneumonia may result
病毒性或细菌性病原体感染

from viral +/- bacterial infection
或者通过免疫病理反应

or through immunopathogenesis.
可导致肺炎

Viral production may be controlled
病毒产物可以在

within 4 to 6 days post infection,
感染后4到6天内得到控制

but tissue damage due to innate and
但是固有免疫和炎症反应引起的

immune inflammatory responses continue.
组织损伤会持续存在

Systemic symptoms are
系统性的症状由

caused by the interferon
对病毒的免疫应答

and cytokine response to the virus.
从而诱导出的干扰素和细胞因子引发

Local symptoms (runny nose, cough, etc.)
局部症状（如流涕，咳嗽等）

result from epithelial cell damage,
则是由于包括纤毛上皮细胞和

including ciliated
分泌黏液细胞在内的

and mucus-secreting cells.
上皮细胞的损伤所致

Immunity is subtype-specific.
免疫反应是亚型特异性的

Antibodies against HA and NA
与HA和NA结合的抗体

are important.
是重要的免疫分子

Cell-mediated immunity also participates.
细胞介导免疫也参与其中

If the girl is diagnosed with flu,
如果这个女孩被确诊为流感

how to treat her,
我们要如何治疗

and how to protect people
以及怎么保护其他人

from the flu virus infection.
免受流感病毒的感染

As what we have learned,
正如我们所学的

we use M2 ion channel blockers
可以用M2离子通道阻滞剂

and neuraminidase inhibitors
以及神经氨酸酶抑制剂

to treat the patients.
来治疗患者

Prevention:
预防措施

Vaccination is the most effective way
疫苗是避免流感病毒感染

to prevent infection and severe outcomes
和其导致的严重后果的

caused by influenza viruses.
最有效的方法

Specific prophylaxis:
特异性预防

Inactivated viral vaccines and "cocktail"
灭活病毒疫苗和“鸡尾酒”

which means trivalent
代表三价或

or quadrivalent vaccines.
四价的疫苗

“The recommended composition
这是世界卫生组织推荐的

of influenza vaccines for use
2020到2021年

in the 2020-2021 northern hemisphere
北半球流感季节中

influenza season”by WHO.
使用的疫苗

The vaccine recommended
推荐的疫苗是

are quadrivalent vaccines.
四价疫苗

Strains of influenza A virus are
甲型流感病毒的菌株

classified by the following
通过以下的特征

characteristics:
进行分类

Type/host of origin
型/宿主

(the host of origin is not indicated
（若宿主是人，则此处不写）

104．
00:06:22,340 --> 00:06:24,100
for human isolates)

/geographic origin/strain number/
/地域起源/菌株编号/

year of isolation
分离年份

(antigenic descriptions
（对于HA和NA的

of the HA and the NA)
抗原性的描述）

So, let's look at the first one
那么，让我们一起看看

of the vaccine.
第一种疫苗

It is a type A virus,
这是甲型流感病毒

host of origin is human,
宿主是人类

isolated in Guangdong-Maonan,
在广东毛南分离出来

strain number is SWL_1536,
菌株编号为SWL_1536

isolated in 2019, the subtype is H1N1.
分离时间为2019年，其亚型是H1N1

Prevent the epidemic of the avian
阻止禽流感病毒的传播

influenza is the first line precaution.
是预防的第一道防线

Outbreaks of avian influenza require
预防禽流感病毒的爆发需要

destruction of all potentially
把所有可能感染的禽类

infected birds.
杀灭

The flu virus is not stable
流感病毒在室温下

at room temperature.
不稳定

It can be inactivated when heated
56°C 30分钟

at 56°C for 30 min,
会失活

and is sensitive to ether
并且对乙醚

and protein denaturants.
和蛋白质变性剂敏感

Now, let's go back
现在让我们再一次

to this question again.
回到这个问题上

Will a killer pandemic
像1918年流感一样的

like the 1918 flu come again?
致死性的流行病会再度发生吗？

After learning the treatment
学习治疗手段

and prevention,
和预防措施后

you may change your mind.
你也许会改变你的想法

If we can treat the patients efficiently,
如果我们对患者进行有效的治疗

and make new vaccine soon,
并且尽快研制出新的疫苗

the disaster may not come again.
这场灾难也许不会再度发生

Key points of this chapter are:
这一章节的核心内容是

Influenza viruses cause
流感病毒

respiratory infections worldwide;
引起全球范围呼吸道感染

there are three types: A, B, and C.
分为三型：甲型，乙型和丙型

Influenza A are segmented RNA viruses
甲型流感病毒是分节段RNA病毒

that regularly undergo genetic changes.
会发生基因变异

The surface proteins,
病毒包膜表面蛋白质

the hemagglutinin and the neuraminidase,
血凝素和神经氨酸酶

can show gradual change
可以发生抗原变化

(antigenic drift) and
抗原漂移

sudden major change (antigenic shift).
和抗原转换

The disease may be pandemic,
可以是全球大流行

epidemic or sporadic.
区域流行或散发

Vaccines have been available
疫苗已经

for many years,
问世多年

recommended annual
专家建议高危人群

for the high-risk groups
应当在病毒大流行期间

in interpandemic period
接种流感疫苗

to reduce mortality,
从而降低发病率，入院率

morbidity and hospital admissions.
以及致死率

The analysis of the case by applying
应用基础知识

the basic knowledge.
对案例进行分析

To answer what, what is the disease.
然后回答是什么，患者得了什么病

Based on the history,in flu season,
根据病史，流感季节

sudden onset of the symptoms and signs,
突发的症状和体征

including high fever,
包括高烧

severe headache and muscle ache,
重度头痛和肌肉疼痛

a little bit of runny nose
轻度流鼻涕

and sore throat,
以及咽痛

the preliminary diagnosis is flu.
初步诊断为流感

To confirm the diagnosis,
确诊

we can detect the virus by isolating
可以对病毒进行分离

and identifying methods,
和鉴定

such as embryonated eggs and HA test,
例如鸡胚培养和血凝素试验

or cell culture by hemadsorption test.
或细胞培养和红细胞吸附实验

Or we can use serologic test,
或者可以使用血清学试验

usually hemagglutination inhibition test
通常是血凝抑制试验

to measure the antibodies titer
在双份血清中

in paired sera.
检测抗体效价

Then answer the second question,
接着回答第二个问题

why did the person become infected?
为什么会被感染？

The source of the infection is patients
感染源自于患者

and asymptomatic carriers.
以及无症状的携带者

Transmission route
传播途径

is the respiratory tract.
是呼吸道传播

The severe disease may be caused by
严重的疾病可由

immunopathogenesis,
免疫病理导致

such as cytokine storm.
比如细胞因子风暴

Last question how to treat
最后一个问题是

and prevent the diseases.
如何治疗和预防这种疾病

Treatment,
治疗手段是

we have covered two kinds of drugs,
我们提到过的两种药

amantadine and ostamivir.
金刚烷胺和奥司他韦

Prevention,
预防措施

please note vaccine
请注意

is the most effective way
疫苗是保护人类的

to protect humans.
最有效的方式

But because of the antigenic drift
但是因为抗原漂移

and shift,
和抗原转换

it's not always full protective.
疫苗并不总是具有保护性

Have a break now.
现在休息一下

We will discuss paramyxoviruses
下一次课

when we meet next time.
讨论副粘病毒