1.Infection and Immunity Infection:is the process in which pathogen parasitizes the human body or host,and a course of active interaction between human body and the pathogen Infectious diseases:diseases caused by pathogen including communicable and non- communicable diseases Communicable diseases:belongs to infectious diseases
1.Infection and Immunity ◼ Infection: is the process in which pathogen parasitizes the human body or host, and a course of active interaction between human body and the pathogen ◼ Infectious diseases:diseases caused by pathogen ,including communicable and noncommunicable diseases ◼ Communicable diseases：belongs to infectious diseases
Outcome of Infection Pathogen Clearance or Eradication Inapparent Infection (subclinical Infection) apparent Infection(clinical Infection) Pathogen Carrier State Latent Infection
Outcome of Infection ◼ Pathogen Clearance or Eradication ◼ Inapparent Infection (subclinical Infection) ◼ apparent Infection (clinical Infection) ◼ Pathogen Carrier State ◼ Latent Infection
(A)Pathogen clearance cleared by nonspecific immunity,or neutralized by specific active or passive immunity of the body. Vibrio cholerae is cleared by gastric acid
(A) Pathogen clearance ◼ cleared by nonspecific immunity, or neutralized by specific active or passive immunity of the body. ◼ Vibrio cholerae is cleared by gastric acid
(B)Inapparent Infection Inapparent infection has no signs,symptoms, even biochemical change clinically and only can be detected by immunological tests. most communicable disease-commonest result.(epidemic encephalitis B,polio) After inapparent infection,most people can acquire specific active immunity
(B) Inapparent Infection ◼ Inapparent infection has no signs, symptoms, even biochemical change clinically and only can be detected by immunological tests. ◼ most communicable disease-commonest result. (epidemic encephalitis B, polio) ◼ After inapparent infection, most people can acquire specific active immunity
(C)Apparent Infection the percentage of apparent infection is low in most But a few show high percentage apparent infection, such as measles,smallpox,etc. After AI,usually acquire consolidated immunity (like typhoid)or temporary immunity (like bacillary dysentery
(C) Apparent Infection ◼ the percentage of apparent infection is low in most, But a few show high percentage apparent infection, such as measles, smallpox, etc. ◼ After AI, usually acquire consolidated immunity (like typhoid) or temporary immunity (like bacillary dysentery )