Human_health_and_disease[人类健康与疾病_]PPT格式课件下载.pptx

1、Human Health and DiseaseWhat is health?#,The state of complete physical,mental and social well-being,To sustain a healthy lifestyle person needs:#,Good hygiene will reduce the likelihood of infection,A balanced and varied diet Take exerciseProper shelter Enough sleep,What is disease?#,Disease is a d

2、isorder or malfunction of the mind or body,which leads to a departure from good health.,Can be a disorder of a specific tissue or organ due to asingle cause.E.g.malaria.,May have many causes.Often referred to as multifactorial.E.g.heart disease.,Disease diagnosed by a doctor analysingthe symptoms（ph

3、ysical and mental signs）.,Acute disease,Sudden and rapid onset,Symptoms disappear quickly,E.g.influenza,Chronic disease,Long term,Symptoms lasting months or years,E.g.Tuberculosis,Categories of diseases,Physical disease,Results from permanent or temporary damageto the body,Infectious diseases,Organi

4、sms that cause disease inside the human body arecalled pathogens,Bacteria and Viruses are the best know pathogens.,Fungi,protists and parasites can also cause disease,Diseases are said to be infectious or communicable if pathogens can be passed from one person to another.,Examples:#,Influenza（flu）In

5、fluenza is a virus which causes a severe form of respiratory tract infection with generalised bodily symptoms.It spreads around the world in epidemics and is responsible for much ill health as well as many deaths.SymptomsIf you start to develop cold symptoms but starting more rapidly and rather more

6、 violently,with higher fever and severe aches and pains,often in the back and muscles,then you may well be developing influenza.This may be associated with severe headache,cough,and,as a result of the fever,intermittent sweating and shivering.Sometimes there is a gastrointestinal element,with vomiti

7、ng and/or diarrhoea.Many people think they have had flu when all that they have suffered is a bad cold.When you have influenza you will know the difference.Most people will find it impossible to leave their bed and feel terrible.The worst symptoms usually last for three to five days,and then should

8、begin to improve.It is common to need two to three weeks off work as there is considerable debility left after the feverish illness is over.Do not be surprised to be quite depressed,this is a natural after-effect of the condition.Influenza makes everyone feel terrible,but most people recover.It does

9、 however have a small,but significant mortality,especially in the very young,the very old,and those with poor immunity.CausesInfluenza is caused by a virus which attacks our body cells resulting in various manifestations depending on the strain of the virus.New mutations of the virus arise all the t

10、ime and unfortunately immunity against one strain（which is conferred by exposure or immunisation）does not protect against other strains.In the era of rapid air transport the world wide spread of a new type of influenza can be extremely fast.,Measles,Chickenpox,Salmonella,Salmonellosis is an infectio

11、n with a bacteria called Salmonella.Most persons infected with Salmonella develop diarrhea,fever,and abdominal cramps 12 to 72 hours after infection.The illness usually lasts 4 to 7 days,and most persons recover without treatment.However,in some persons the diarrhea may be so severe that the patient

12、 needs to be hospitalized.In these patients,the Salmonella infection may spread from the intestines to the blood stream,and then to other body sites and can cause death unless the person is treated promptly with antibiotics.The elderly,infants,and those with impaired immune systems are more likely t

13、o have a severe illness,Cholera,Cholera is an acute,diarrheal illness caused by infection of the intestine with the bacterium Vibrio cholerae.The infection is often mild or without symptoms,but sometimes it can be severe.Approximately one in 20 infected persons has severe disease characterized by pr

14、ofuse watery diarrhea,vomiting,and leg cramps.In these persons,rapid loss of body fluids leads to dehydration and shock.Without treatment,death can occur within hours.,Typhoid,Typhoid fever is contracted when people eat food or drink water that has been infected with Salmonella typhi.It is recognize

15、d by the sudden onset of sustained fever,severe headache,nausea and severe loss of appetite.It is sometimes accompanied by hoarse cough and constipation or diarrhoea.Case-fatality rates of 10%can be reduced to less than 1%with appropriate antibiotic therapy.Paratyphoid fever shows similar symptoms,b

16、ut tends to be milder and the case-fatality rate is much lower.,Water or food borne,Gonorrhoea,This is caused by bacteria and can affect the vagina,cervix,urethra,rectum or even the throat.How could I get it?#Gonorrhoea can be passed on through:#vaginal sex-where the man puts his penis in the womans vagina anal sex-where the penis is put into the rectum oral sex-where partners lick or suck each others sexual parts.Can I get it from toilet seats or towels?#You cannot it get it from toilet seats or swimm