Pathogenesis of Viral infection在线视频

Question 6.
第六个问题

How does viral infection
病毒感染的

anifest itself?
临床表现

Principles of viral diseases
病毒性疾病的原则

1.Many viral infections are subclinical.
1.很多病毒感染是亚临床感染

2.The same disease
2.不同种类的病毒

may be produced by a variety of viruses.
可能会引起同一个疾病

3.The same virus may produce
3.同一种病毒可能会

a variety of diseases.
引起多种疾病

4.The disease produced
4.疾病

bears no relationship
与病毒形态

to viral morphology.
无关

5.The outcome in any particular case
5.临床案例的转归

is determined by
都是由病毒和宿主

the interaction of the virus
之间的相互作用

and the host
所决定的

and is influenced
而且受到我们每个人基因

by the genetics of each.
的影响

Major target tissues of viral disease
病毒性疾病主要的靶组织

As we mentioned just now,
正如我们刚刚提到的

the same disease
不同种类的病毒

may be produced by a variety of viruses.
可以引起同一疾病

For example,
例如

HSV-1，toga, picornavirus, rabies virus,
单纯疱疹病毒、披膜病毒、小RNA病毒、狂犬病毒

all can produce encephalitis.
都可以引起脑炎

The same virus may produce
而同一种病毒则可能会引起

a variety of diseases.
各种各样的疾病

For example,
例如

coxsackievirus can cause
柯萨奇病毒可以引起

mycocarditis, and also pharyngitis.
心肌炎和咽炎

Iceberg concept of infection
感染的“冰山概念”

As we all know,
我们都知道

we can only see the tip of the iceberg
我们仅仅只能看到海平面之上

which is above the surface of the sea,
冰山的一角

and large part
而冰山的大部分

of the iceberg is beneath.
是看不见的

Viral infection has the iceberg concept.
病毒感染也有“冰山概念”

Only few become symptomatic.
只有很少的病毒感染会有症状

They show mild to severe diseases.
表现为轻微或严重的疾病

Most of the others are asymptomatic,
而其他绝大部分病毒感染都是无症状的

and classified as subclinical infection.
即隐性感染或亚临床感染

Types of viral infection include
病毒感染的类型包括

inapparent and apparent infections
隐性感染和显性感染

Inapparent or subclinical infections
隐性感染或者亚临床感染

are the viral infections
是指病毒

that fail to produce
进入机体

any symptoms in the host.
而不引起临床症状的感染

Actually, most viral infections
事实上，大部分病毒感染

do not result in
不会导致

the production of disease.
疾病

Apparent infection include
显性病毒感染包括

acute infection
急性感染

and persistent infection.
和持续性感染

The outcome is determined
感染的结果是

by the interaction
由病毒和宿主

of the virus and the host.
之间的相互作用所决定的

Acute infections
急性感染

are clinical manifestations of disease
是指疾病的临床表现

last for a short time.
只持续一小段时间

Viral infections
病毒感染

are usually self-limiting
通常是自限性的

Persistent infection:
持续性感染

the virus persists
病毒存在机体内

for long periods of time in the host.
相当长一段时间

Long-term virus-host interaction
病毒和宿主之间长期的相互作用

may take several forms:
可能会呈现几种形式

①Chronic infection
1.慢性感染

②Latent infection
2.潜伏感染

③Slow infection
3.慢发感染

④Acute infection with late complications
4.急性感染合并晚期并发症

The ability and speed with which
个体的免疫系统调控

a person’s immune system controls
和解决病毒感染问题

and resolves a viral infection
的能力和速度

usually determines
通常决定了

whether acute or chronic disease
疾病是急性还是慢性的

and the severity of the symptoms.
以及症状的严重程度

Acute infection:
急性感染

common cold and most viral infections
普通感冒和大部分病毒感染

are acute infections.
都是急性感染

Acute infection, rare late complication,
急性感染，很少有晚期并发症

such as measles and SSPE
例如麻疹和SSPE

(subacute sclerosing panencephalitis ).
（亚急性硬化性全脑炎）

Latent-recurrent infections.
潜伏-复发性感染

e.g. varicella-zoster virus (VZV).
例如水痘-带状疱疹病毒（VZV）

The acute infection
水痘是

is varicella (chickenpox),
急性感染

and then the virus is latent in neurons,
然而病毒在神经元里有潜伏性

and later under certain circumstance,
如果在特定条件下

the viruses can come out
病毒再次出现

and cause zoster.
并引起带状疱疹

The hallmark of herpes virus infection,
疱疹病毒，例如VZV

which VZV is one, is latent infection.
的特点是潜伏感染

Chronic infection: e.g. HBV and HCV.
慢性感染，例如HBV和HCV

Chronic infection,
慢性感染

late disease. e.g. HIV.
晚期疾病，例如HIV

After infected by HIV,
被HIV感染后

the patient may show typical symptoms
病人可能在十年之后

and signs after 10 years.
才出现典型的症状和体征

Slow viruses and prions
慢发病毒和朊病毒

have long incubation periods
有很长的潜伏期

during which sufficient virus
在潜伏期内

or tissue destruction accumulates
直到病情快速发展前

before a rapid progression of symptoms.
已经累积了大量病毒和组织破坏

A quiz,
我们来看一个题目

the hallmark
疱疹病毒最显著的

of infection of Herpes virus is
感染的特点是

A.Chronic infection
A.慢性感染

B.Latent infection
B.潜伏感染

C.Slow infection
C.慢发感染

D.Acute infection
D.急性感染

with late complications
伴晚期并发症

Which one is correct?
哪一个选项是正确的？

Yes, B.
没错，答案是B

The hallmark of infection
疱疹病毒感染

of Herpes virus is latent.
的特点就是潜伏性

Question 7,
第七个问题

how can viral diseases be transmitted?
病毒性疾病是怎么传播的？

There are vertical
它的传播方式有

and horizontal transmissions.
垂直传播和水平传播两种

Vertical transmission:
垂直传播

viruses can be transmitted
病毒可以由亲代

from mother to offspring
通过胎盘、产道

via the placenta, the birth canal,
或者母乳喂养

or during breast feeding.
传播给子代

e.g. rubella virus,
例如风疹病毒

CMV(cytomegalovirus),
CMV（巨细胞病毒）

herpes virus, HIV
疱疹病毒、HIV

Please remember“TORCH”.
请大家记住“TORCH”

"TORCH" refers to the microbes
“TORCH”指的是

that may pass from mother to fetus.
可以从母亲传播给胎儿的微生物

T Toxoplasma;
T指弓形虫

R rubella virus,
R指风疹病毒

C cytomegalovirus,
C指巨细胞病毒

H HIV and Herpes simplex virus-2,
H指HIV和单纯疱疹病毒-2

hepatitis virus type B and C,
乙肝病毒和丙肝病毒

O others, include syphilis,
O指其他，包括梅毒

Parvovirus B19 etc.
细小病毒 B19等

Another one is horizontal transmission.
另外一种传播方式是水平传播

Viral infections transmitted
病毒通过非基因的途径

from one individual to another
从一个人

by non-genetic means.
传播给另一个人

Viruses may spread via the respiratory,
病毒可以通过呼吸道

gastrointestinal,
消化道

skin injury or through sexual contact.
破损皮肤或性接触传播

Question 8,
第八个问题

how do we confirm the diagnosis
我们怎么通过实验室检查

by laboratory test?
来确诊病毒感染？

Effects of viral infection
病毒感染

on cells include
对细胞的作用包括

1.Cytocidal infection
1.杀细胞效应

(Lytic infection)
（裂解性感染）

2.Steady state infection
2.稳定状态感染

3.Cell apoptosis
3.细胞凋亡

4.Integrated viral infection
4.基因整合

5.Transformation
5.细胞转化

Many viruses can produce
很多病毒可以引起

a cytopathic effects (CPE).
一种细胞病变效应（CPE）

Characteristic CPEs
在组织样本

in the tissue sample
或在细胞培养里

or in cell culture include changes
典型的细胞病变效应包括

in cell morphology,
细胞形态的改变

cell lysis or necrosis,
细胞溶解或坏死

inclusion body formation,
包涵体的形成

giant cell formation,
巨细胞的形成

and cytoplasmic vacuolization.
还有细胞质空泡形成

Inclusion body.
包涵体

In the course
病毒在细胞里

of viral multiplication within cells,
增殖的过程中

viral specific structures
可能会产生

may be produced.
病毒的特征性结构

They become far larger
它们比单独的病毒颗粒

than the individual viral particle
要大得多

and often have an affinity
而且通常

for acid dyes.
对酸性染料有亲和力

They may be situated in the nucleus,
包涵体可能位于细胞核

in the cytoplasm, or in both.
细胞质，或者都有

The photo shows an example
这张图片展示了

of inclusion body.
包涵体的一个例子

Characteristic
可以看到

“Negri bodies” are present
一个死于狂犬病的病人

within a neuron;
神经元里

patient died of rabies.
典型的“内基小体”

The pictures show you
这张图片给你们展示了

the intranuclear
感染巨细胞病毒的

basophilic inclusion bodies
细胞核里有

with cytomegalovirus (CMV).
嗜碱性的包涵体

The intranuclear inclusion body
细胞核里的包涵体

has a typical “owl-eyed” appearance
有着典型的“猫头鹰眼”外形

Multinucleated giant cells
单独的细胞

are formed by viral fusion
被病毒融合后

of individual cells.
会形成多核巨细胞

Paramyxoviruses, such as measles,
副黏液病毒，例如麻疹

respiratory syncitial virus (RSV),
呼吸道合胞病毒（RSV）

and HSV, VZV, and HIV
HSV、VZV和HIV

promote the formation
会促进

of multinucleated cells.
多核细胞的形成

Integrated virus infection.
基因整合

The viral genetic information
病毒的遗传信息

may be integratedas DNA
可以被整合到

in the cellular genome
宿主细胞的基因组中

or may persistas episomal DNA
或者存在于存活细胞的

in these surviving cells.
游离基因的DNA中

Transformation is a change
细胞转化是指

in the morphological,
在细胞形态

biochemical or growth
生物化学

parameters of cells.
生长因素上的改变

Only members of some virus families
只有某些病毒家族的成员

are able to transform cell.
能够导致细胞转化

These include
包括

Herpesviruses,
DNA病毒里的疱疹病毒，

Adenoviruses,
腺病毒，

Hepadnaviruses,
肝细胞核酸病毒，

Papovaviruses,
乳多泡病毒，

and poxviruses of the DNA viruses,
和痘病毒

and, of the RNA viruses,
而RNA病毒

only retrovirus.
只有逆转录病毒

Viruses and associated
这张图片展示了

malignant diseases
病毒和

are showed in this table.
相关的恶性疾病

HTLV, adult T cell leukaemia.
HTLV，成人T细胞白血病

HPV-16 (human papillomavirus type-16),
HPV-16（人乳头状瘤病毒-16）

carcinoma of the cervix.
子宫颈癌

EBV (Epstein-Barr virus),
EBV（EB病毒）

Burkitt's lymphoma,
伯基特淋巴瘤

and nasopharyngeal carcinoma.
和鼻咽癌

HBV and HCV,
HBV和HCV

are associated with liver cancer
和肝癌有关

HHV-8, Kaposi's sarcoma.
HHV-8，卡波西肉瘤

These are the effects
这些是病毒感染

of viral infection on cells
对于细胞的效应

1.Cytocidal infection (Lytic infection )
1.杀细胞效应（裂解性感染）

2.Steady state infection
2.稳定状态感染

3.Cell apoptosis
3.细胞凋亡

4.Integrated virus infection
4.基因整合

5. Transformation
5.细胞转化

When we see any of above CPE,
如果我们发现以上细胞病变效应的任何一种

its highly suggestive
它都强烈暗示

of a viral infection.
可能存在病毒感染

But we still need to confirm
但是我们仍然需要

with lab test.
通过实验室检查来确诊

Thank you for your attention.
谢谢大家

See you next time.
我们下次见