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PART I 1 and practiced tyndallization History of Medical —father of microbiology Fig. 1–1. Pasteur’s achievements in the field of sterilization Pasteur developed against chicken wounds from airborne microbes by applying wounds from airborne microbes by workers dressing and making medical and paramedical before they wash their hands with antiseptic solution He achieved touched any exposed part of a patient. brought down strikingly successful results and sepsis. tremendously the mortality due to were closely followed by many other workers.Tyndall introduced the method of sterilization by repeated heating with appropriate intervals for germination of spores between them and their subsequent destruction. The method is known as even today. and by using attenuated suspension of . . animalcules theory of spontaneous or spontaneously in the media but . de novo Pasteur also showed that were Pasteur’s demonstration of airborne microbes For many years it was believed that the micro- For many years it was believed CONTRIBUTIONS OF LOUIS PASTEUR Louis Pasteur (1822-1895), a French chemist generated strong evidence to show that the microorganisms did not rise were introduced from without. Pasteur showed that these organisms were maximum in the dusty air of towns and minimum in air of hilly areas where human habitation did not exist. inactivated by • boiling • at 120°C under pressure (autoclaved) • at 170°C (hot air oven) prompted ’s (1827-1912) work on wound sepsis. He introduced the practice of protecting the At a very early stage man developed concept that At a very early stage man developed by invisible living contagious was caused proved it to be a things.Invention of the designed reality. Antony van Leeuwenhoek (1632-1723) the little a single lens microscope and demonstrated as agents of disease, which he designated These animalcules are now well established entities These animalcules are now well and several other belonging to bacteria, to naked eye . The organisms being invisible are known as microorganisms. decomposed organisms arose from dead, especially organic matter. This was known as generation PART I .Whensuchpurecultureisinoculatedintoappro- C. Itshouldbepossible toisolatethecausativeagent B. Theisolateshouldbefoundineverycaseofthe A. followings aresatisfied: causative agentofaninfectiousdiseaseonlyifthe postulates, amicroorganismcanbeacceptedas a postulated asetofcriteria.Accordingtothese from adiseasewasindeedthecauseofthis,Koch To confirmtheclaimthatamicroorganismisolated Koch's Postulates bacteriology. bacteriology, Kochisconsideredasfatherof 1883 thecholeravibrio.Forhismanifolddiscoveriesin bacillus ofanthrax. tration ofthecharacterandmodegrowthcausative 'sfirstcontributiontosciencewasdemons- rised asfollows lives consequenttobitesbyrabidanimals. It hasbeenresponsibleforsavinginnumerablehuman ment ofrabiesvaccinefromthespinalcordrabbits. an enormousreductioninmortalityamongstsheep. Soon anthraximmunizationwaswidelypractisedwith protected themfromtheeffectsofvirulentbacteria. attenuated organisms,oninjectionintoanimals, use ofcowpox,hereferredtothisasvaccination.These In ordertoshowthattheprocesswasakinJenner’s 2 CONTRIBUTIONS OFROBERTKOCH should bereproduced priate laboratoryanimal, the lesionofdisease in pureculturefromthelesion pathological changesandclinicalfeatures disease andunderconditionswhichexplainthe In 1882,Kochdiscoveredtuberclebacillusandin Developmentofinitialbacteriologicaltechniques • Microbialtheoryoffermentationandprovingthatall • The discoveriesmadebyPasteurcanbesumma- However, hisepochmakingdiscoverywasdevelop- Essentials of Medical of Essentials Developmentofvaccinesagainst: Controlofdiseasessilkworms • • Principlesandpracticeofsterilization • their likeandnotspontaneously forms oflifeincludingmicroorganismsarisefrom — Chickencholera — Anthrax — CONTRIBUTIONS OFLOUISPASTEUR patient sufferingfromthedisease. the bacteriumshouldbedetectableinserumof which demandsthatspecificantigensorantibodiesto Itshouldbepossibletoreisolatethecausativeagent D. . Table1.1showssome importantdiscoveries. ing ontherelationofbacteria tohumanandanimal succession ofdiscoverieswere reportedwhichhadbear- summarised asunder: Inabilitytogrowmanyvirusesandrickettsialpatho- b. Inabilitytogrow a. Postulates Some oftheexceptionsthesepostulatesare: Koch's to Exceptions Subsequently anothercriterionhasbeenintroduced experimental animal(Fig.1.3). in pureculturefromthelesionproduced During thelastquarterofnineteenthcentury, Use oflaboratoryanimalsforexperimentalinfections Koch’spostulates. • • Discovery ofcausativeagentsof: Discoveryanduseofsolidmediuminbacteriology • • Introductionofstainingtechniquesforvisualization • Verification ofgermtheorydiseases The lifelongachievementsofRobertKochare gens onartificialmedia and leprosyrespectivelyonartificialmedia bacterium leprae Anthrax — Cholera — — of microorganisms Fig. 1–2. 1–2. Fig. CONTRIBUTIONS OFROBERTKOCH Robert Koch—fatherofbacteriology -known causativeagentsofsyphilis Treponema pallidum and Myco- PART I 3 History of Medical Microbiology —father of chemotherapy Fig. 1–4. In 1910, Ehrlich successfully treated using In 1910, Ehrlich successfully treated the 1900s he cured one form of trypanosomiasis in rats the 1900s he cured one form of trypanosomiasis form in mice with with the dye trypan red and another an organic arsenic compound, atoxyl. dihydro- compound '606'’ (dioxydiaminoarsenobenzol Fleming discovered chloride) and called it Salvarsan. Subsequently, and Waksman streptomycin. of several fungi have been used as source substances. Koch’s postulates Fig. 1–3. Discovered by Hansen Neisser Eberth Ogston Pasteur and Sternberg Robert Koch Loeffler and Shutz Robert Koch Fehleisen Loeffler Nicolaier Weichselbaum Bruce Pfeiffer Welch and Nuttall Yersin and Kitasato Ermengem Shiga Discoveries of bacteria in 19th Century Neisseria gonorrhoeae Salmonella typhi Pneumococcus M. tuberculosis Bacillus glanders Vibrio cholerae C. diphtheriae Clostridium tetani Neisseria meningitidis Brucella melitensis Clostridium welchii Yersinia pestis Clostridium botulinum Shigella leprae Table 1–1. 1879 1880 1881 1881 1882 1882 1883 1883 1884 1885 1887 1887 1892 1892 1894 1896 1896 Year1874 Organism ANTIMICROBIAL AGENTS With the identification and confirmation of bacteria as causative agents of human diseases, efforts were made to develop effective agents which could kill bacteria in the body of the man without damaging the host tissue. Pioneer work was done by Paul Ehrlich (Fig. 1.4) who is justly described as the father of chemotherapy. In PART I 4 Advocatedstandardizationofbiologicalsincluding Refinedthescienceofstainingorganisms • • Proposedatheoryfortheproductionofantibody Identifiedthatmycobateriahaveacidfastnessnature • • Discoveryofsalvarsanasachemotheraputicagent • Essentials of Medical Microbiology Medical of Essentials toxins andantitoxinstoensureuniformity called as"sidechaintheory" millions ofpeopletilldate antimicrobial agentswhichhassavedthelivesof against syphilis.Thisopenedthenewfieldof 97Puie Radio Prusiner Doh 2002 2001 1999 1997 1996 1993 1990 1989 Yalow 1987 1984 1983 1980 1978 1977 1976 1975 1972 1969 1968 1965 1962 Contributionin/discoveryof 1960 Domagk 1958 1954 Nicolle 1952 Bordet 1951 1945 1939 1930 1928 Sir 1919 Von 1913 NobelLaureate 1908 1908 1905 1902 1901 Year CONTRIBUTIONS OFPAULEHRICH utrBoe Intrinsicsignalsin proteins Genetic regulationoforgandevelopmentandcelldeath Keyregulators ofcellcycle Useofimmunosuppressive drugsintransplantation Oncogenes Geneticsofantibody production Brenner, HorvitzandSulston Hartwell, HuntandNurse Monoclonal Gunter Blobel Sharp andRoberts MHCgenesandtransplantation Restrictionenzymes Murray andThomas Chronic viral infectionsandcancers Bishop andVarmus Natureandstructureofantibody Susumu Tonegawa Milstein,Kohler andJerne Reversetranscriptaseandcausationofcancer Barbara McClintok Benacerraf,Snell andDausset Mechanism ofviralinfectionbacteria Protein synthesis in bacteria Streptomycin Nathans, SmithandArber Immunological tolerance code Genetic DNA of Structure fever Yellow Blumberg andGajdusek Baltimore and Temin Dulbecco, Edelman andPorter Bacterial genetics Bloodgroup Delbruck, HersheyandLuria Holley, KhoranaandNirenberg Penicillin Jacob, MonodandLwoff Watson, CrickandWilkins Phagocytosis Burnet andMedawar Theoriesonimmunity Beadle, TatumandLederberg Tuberculosis Enders, Wellerand Waksman Marx Theiler Fleming, Chain&Florey Landsteiner Richet Metchnikoff Paul Ehrlich Robert Koch Ronald Ross ryadZnenglRecognition ofvirusesbyimmunesystem erty andZinkernagel ern Diphtheriaantitoxin Behring Table 1–2. Nobellaureatesinmicrobiologyandimmunology obn Poliomyelitis Robbins logy wasyellowfever. The firsthumandiseaseproventohaveavirusaetio- made morphologicalexaminationofvirusespossible. cold. Adventofelectronmicroscopyin1934byRuska included smallpox,chickenpox,measlesandcommon which nobacteriumcouldbedemonstrated.These remained manydiseasesofcommonoccurrencefor The trendcontinuedintwentiethcentury.Butyetthere diseases hadbeenproventohaveabacterialaetiology. By theendofnineteenthcenturymanyinfectious DISCOVERY OFVIRUSES Gene splicing Transposons asantibacterial Typhus Immunity Anaphylaxis immunoassays PART I 5 CoVirus) ARS of infantile diarrhoea worldwide of infantile chronic diarrhoea History of Medical Microbiology babesiosis subitum haemorrhagic fever stic crisis in chronic heamolytic anaemia stic crisis in chronic heamolytic Haemorrhagic fever with renal syndrome (HRFS) Haemorrhagic fever with T-cell lymphoma -leukaemia Hairy cell leukaemia AIDS Enterically transmitted Parenterally transmitted liver Venezuelan haemorrhagic fever Conjuctivitis ;disseminated disease Adult respiratory distress syndrome Disseminated disease Brazilian haemorrhagic fever Associated with Kaposi sarcoma in AIDS patients Encephalitis SARS Discovery of New Organisms is a continuous The discovery of new microorganisms organisms have phenomenon. A large number of new been discovered in recent past (Table 1.3). Some of these have acquired considerable importance because of the mortality and morbidity caused by them (HIV, , ) and others have the capability to international scare (S Avian VirusParasiteVirus Major cause Bacteria and Acute Bacteria Ebola Legionnaires disease Bacteria Enteric distributed globally Toxic Shock Syndrome BacteriaBacteria Lyme disease ParasiteParasite Peptic ulcer disease Virus Persistent diarrhoea Virus Persistent diarrhoea BacteriaVirus Roseola Human ehlichiosis Parasite ParasiteBacteria Atypical Parasite Cat –scratch disease;bacillary angiomatosis Virus (HTLV-1) Virus Staphylococcus aureus Recently recognized pathogenic microbes and infectious diseases microbes and infectious pathogenic Recently recognized O157:H7 Bacteria Haemorrhagic colitis; heamolytic Ureamic syndrome O139 Bacteria associated with cholera New Babesia Table 1-3. sps. of nombre virus Virus RS CoVirus Virus Influenza virus H5N1 Parvovirus B-19Cryptosporidium parvum Ebola virus Legionella pneumophila Hantaan VirusCampylobacter jejuni virus I Human T- lymphotropic of Toxin producing strains Escherichia coli Borrelia burgdorferi Helicobacter pylori VirusEnterocytozoon bieneusi Cyclospora cayatanensis Human herpes virus-6 (HHV-6) Apla Hepatitis E Virus Virus Ehrilichia chafeensis Hepatitis C Virus Guanarito virusEncephalitozoon hellem Vibrio cholerae Bartonella henselae Encephalitozoon cunculi Sabia virus Virus Virus In 1930s viruses could be grown in bacteria free, In 1930s viruses could be grown 2004 1982 HTLV-II Virus 1975 1976 1977 1977 1977 1977 1980 1981 1982 1982 19831983 1985 1986 1988 HIV1988 1989 1989 1991 1991 19911992 1992 19931993 New 1994 19951999 Sin 2002 HHV-8 Virus Nipah SA Virus Year1973 Microbe Type Disease NOBEL LAUREATES A number of Nobel laureates in and Physio- logy were awarded this prize for their work in Micro- biology and (Table 1.2). living chick embryo—a technique perfected by living chick embryo—a technique tissue culture of Goodpasteur. By 1940, growth in susceptible mammalian cells was established. The availability of well defined cell lines have now repla- ced tedious methods of growing viruses in the living animals.