课件：传染病学绪论华中科技大学同济医学院.ppt

Prof. Qin Ning (宁琴), MD. PHD Department of Infectious Disease, Tongji Hospital,Introduction to Infectious Diseases,TONGJI MEDICAL COLLEGE HUAZHONG UNIVERSITY OF SCIENCE & TECHNOLOGY,What is an Infectious Disease?,Infectious Diseases - caused by human infection of micro-organisms and parasites Infection - the ability of an organism to invade and establish itself in a host Communicable Infection - a disease that is transmitted from person to another,What is an Infectious Disease?,Microorganisms Bacteria Virus Prion(盶毒体) Fungus Protozoa (原虫) Helminth (蠕虫) Products from microorganisms toxins,Current Situation,Increasingly serious threats from Communicable diseases Re-emerging: TB(结核), STD, plague(瘟疫), cholera(霍乱) Emerging: AIDS, SARS,The Incidence Rate of Communicable Diseases in China,Current Situation,The Proportion of Different Communicable Diseases by Etiology in China, 1950s-2002s,Transmitted by sex or blood,Gastrointestinal,Vector-borne and natural endemic,Respiratory,Leading Causes of Death,Reemerging Infectious Disease,Why? Human Demography and Behavior Technology and Industry Economic development and Land Use Microbial Adaptation and Change Breakdown of Public Health Measures and Deficiencies in Public Health,Natural Environment Destroy,Infection and Immunity,infection,immunity,Disease =,Response to Infection,adaptive immunity,Infection spectrum Primary Infection Repeated Infection Mixed Infection Superinfection Secondary Infection,Infection,Pathogen eradication,Overt infection Clinical Infection,Latent infection,Pathogen eradication,Carrier,Patient,Colonization,Carrier,Covert infection Subclinical infection,Bacteremia /viremia,Clinical Outcomes of Infection,Pathogenic effectiveness of micro-organisms,Pathogenecity,Invasiveness (colonization factor),Virulence (exotoxin and endotoxin),Quantity,Variability (HBV mutation),Immunity,Nonspecific immunity,Specific immunity,Natural barrier,Phagocytosis,Humoral factor,Cellular immunity,complement,cytokine,lysozyme,Humoral immunity,IgM,IgA,IgE,IgG,Immune Response in Infection Process,Cells of the Immune System,Leukocytes (Not Ag specific) neutrophils (PMNs) monocyte/macrophage eosinophil basophil Specialized cells (Ag specific) B-cells antibodies T-cells,T cells classification,How does the immune system work?,MHC class I molecule presenting an epitope,Infection and Immune,Infection and Immune (herpes simplex),Initial infection by herpes simplex virus in the skin is cleared by an effective immune response. But residual infection persists in sensory neurons. When the virus is reactivated, the skin is re-infected. This can be repeated endlessly.,Pathogenesis of Infectious Disease,Direct Injury Toxin Harmful Immune response,Invasion,Colonization,Output,Pathogen,Injury,Fever Metabolism disorder Endocrine disturbance,Development of infectious disease,Injury of cells and tissues,Disorder of pathophysiology,Adhesins Capsular material Proteins (Protein F, Protein M) Lipotechoic acids Fimbriae & Pili Endotoxins Gram negative LPS cell wall components (Lipid A and Core Sugars) Exotoxins Can be produced by either Gram Positive or Gram Negative Organisms,Cell and Tissue Damage Induced by Micro-organisms Bacteria,Cell and Tissue Damage Induced by Micro-organisms viruses,Direct attachment and killing Inhibit host cell synthesis (RNA, DNA, proteins) Intracellular replication and lysis Surface targets for host immune system Local direct damage leading to secondary bacterial infections Latent injury,Harmful Host Responses to Infectious Agents,Autoimmunity: break the rules of the “self-versus-nonself”. Direct against “self-proteins” Hypersensitivity reactions type I or immediate hypersensitivity (mast cell associated IgE) type II or cytotoxic hypersensitivity (antibody-complement activation and natural killer) type III or immune-complex-mediated hypersensitivity type IV or delayed-type hypersensitivity (activated T, CD8+, Mac) prolonged antigen exposure,Enterovirus Pathogeneis,Colonized herd,Epidemic Process,Epidemic Process,Source of infection,Route of transmission,Susceptible population,Why do people get sick?,New pathogens or changes in pathogens (HIV, Nile-like virus) Changes in environmental conditions (natural or man-made) Host Factors (Age, gender, ethnicity, immune status, Nutritional status, behavior),Source of Infection,Patient Covert infected person Carrier Infected animal,Other effective factors:,Climate Temperature, Humidity Society Sanitation, Cultural Background, War,Routes of Transmission,Air-borne, droplet infection,dust Fomite borne (污染物): Water, food, flies Direct contact of unclean hands and fingers, toys Vector borne A) mechanical B) biological Blood and blood source products Contact with soil Transplacental,HIVs Transmission Routes,Susceptible Population,A group of people at increased risk for infection and illness from a pathogen, often caused by a decrease in the effectiveness of the persons immune system.,Chain of Transmission,Portal of exit,Portal of entry,Agent,Susceptible Host,Mode of transmission,Reservoir,Person to person transmission,Agent,Host,Environment,Age Sex Genotype Behaviour Nutritional status Health status,Infectivity Pathogenicity Virulence Immunogenicity Antigenic stability Survival,Weather Housing Geography Occupational setting Air quality Food,Factors Influencing Disease Transmission,Distribution due to Socioeconomic,Hepatitis A Typhoid fever Helicobacter pylori Other bacterial diarrheas Tuberculosis,Characteristics of Infectious Diseases,Pathogen Infectivity: isolation of patients Epidemiologic feature: continue with next slide Post-infection immunity,Basic features,Level of Epidemic,Sporadic level - occasional cases occurring at irregular intervals Endemic level - persistent occurrence with a low to moderate level Hyperendemic level - persistently high level of occurrence Epidemic or outbreak - occurrence clearly in excess of the expected level for a given time period Pandemic - epidemic spread over several countries or continents, affecting a large number of people,Clinical Phage,Incubation period (潜伏期) Prodromal period (前驱期) Manifestation period (症状期) Recovery phase (恢复期) Relapse (复发): fully recover and disease re-appeares Recrudescence (再燃): not fully recovered and got worser Sequela (后遗症): functionally not fully recovered,1. Effervescence (increasing) 2. Fastigium (peaking) 3. Defervescence (decreasing),Symptoms and signs,Fever Process,Symptoms and signs,Fever types,Sustained Fever,Remittent Fever,Intermittent Fever (septic fever),Relapsing Fever (Undulant Fever),Saddle Type Fever,Irregular Fever,Fever type,Sustained Fever,Remittent Fever,Intermittent Fever (septic fever),Undulant Fever,Relapsing Fever,Irregular Fever,Skin Eruption,Macule (班疹),Maculo-papule (班丘疹),Roseola (玫瑰疹),Skin Eruption,Petechiae (出血疹),Ecchymosis,Herpes,The Time Rash Appears,Day 1 Rubella (风疹) Day 2 Scarlet Fever (猩红热) Day 3 Small Pox (天花) Day 5 Typhus Fever (班疹伤寒) Day 6 Typhoid (伤寒),Other Symptoms,Conjunctiva congested,Enlargement of lymph nodes,Toxemic symptoms Bleeding Coma Mononuclear-phagocyte system response Spleno-hepatomegaly,Diagnosis,Epidemiology vital and significant in diagnosis Clinical Manifestation such as rose rash, splenohepatomegaly, gastrocnemius tenderness Laboratory Test main means for diagnosis,Laboratory Test,Light Microscopy H & E stained sections Special Stains: Gram, Acid Fast, Giemsa Culture Bacterial, Mycobacterial, Fungal, Viral Immune Test Serologic Studies ELISA Immunoperoxidase Stains Direct Fluorescent Antibodies Polymerase Chain Reaction,Treatment,General and supporting treatment Heteropathy (对症治疗) Pathogenic and specific treatment Rehabilitation therapy Traditional Chinese Medicine and acupuncture treatment,Antibiotic Therapy,Proper dose Proper time interval Proper route of administration (oral, parenteral) Combination antibiotic therapy,The main classes of antibiotics,Aminoglycosides Cephalosporins Fluoroquinolones Macrolides Penicillins Tetracyclines,Antibiotic Resistance,Antiviral Therapy,Interferon Nucleoside Analogues High Active Anti-Retroviral Therapy, HAART Treat HIV,HBV,HCV,Interferon,Lamivudine,Antiparasitic Drugs,Antimalarial (抗疟药) CHLOROQUINE(氯喹) Antiprotozoal Drugs (抗原虫药) Amebiasis(阿米巴病)and Trichomonas(毛滴虫属) METRONIDAZOLE(甲硝唑) Fluke(吸虫) and Tapeworm(绦虫) Infections Schistosomiasis(血吸虫病) PRAZIQUANTEL(吡喹酮) Filariasis(丝虫病) diethylcarbamazine(乙胺嗪) Intestinal Roundworms (Ascaris),(线虫,蛔虫) Enterobius (Pinworm)(蛲虫) and Hookworm(钩虫) Albendazole(丙硫咪唑),Prophylaxis,Sanitation water and waste treatment personal hygiene Vaccination probably the best way to prevent communicable diseases Healthy living practice safe sex avoid drugs Antibiotics and other drugs,Prophylaxis,Law of the peoples Republic of China on Prevention and Treatment of Infections Diseases,Article 3 The infectious diseases governed by this Law are divided into Classes A， B and C. Infectious diseases under Class A are plague and cholera.,Law of the peoples Republic of China on Prevention and Treatment of Infections Diseases,Infectious diseases under Class B are infectious SARS， AIDS， viral hepatitis, poliomyelitis， highly pathogenic avian influenza， measles， epidemic hemorrhagic fever， rabies epidemic encephalitis B， dengue fever， anthrax， bacillary and amebic dysentery， pulmonary tuberculosis， typhoid and paratyphoid， epidemic cerebrospinal meningitis， pertussis， diphtheria， tetanus infantum， scarlet fever， brucellosis， gonorrhoea， syphilis， leptospirosis， schistosomiasis and malaria.,Law of the peoples Republic of China on Prevention and Treatment of Infections Diseases,Infectious diseases under Class C are influenza， epidemic parotitis， rubella， acute hemorrhagic conjunctivitis， leprosy epidemic and endemic typhus， kala-azar， echinococcosis， filariasis， and infectious diarrhea other than cholera， bacillary and amebic dysentery， typhoid and paratyphoid.,Law of the peoples Republic of China on Prevention and Treatment of Infections Diseases,Article 30 When disease prevention and control institutions， medical agencies， blood collectors and supplies or their staff members on duty find the epidemic situation of infectious diseases or the this Law or the outbreak and prevalence of other infectious diseases or the infectious diseases the causes for the sudden outbreak of which are uncertain， they shall report in adherence to the principle of territorial control in respect of report on epidemic situation and in accordance with the contents， procedure， from and time limit prescribed by the State Council or by the health administration department under the State Council.,Brief Review,What is an Infectious Disease? Current Situation Pathogenesis Epidemiology Clin