Illness Transmission and Connection.

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Malady Transmission and Connection Nigel Paneth Triumphs Of The study of disease transmission ID of water as a noteworthy store and vehicle of transferable sicknesses, for example, cholera and typhoid fever (1849 - 1856)
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Ailment Transmission and Context Nigel Paneth

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Triumphs Of Epidemiology Identification of water as a noteworthy store and vehicle of transmittable ailments, for example, cholera and typhoid fever (1849 - 1856) Identification of arthropod vectors for some infections - jungle fever, yellow fever, dozing affliction, typhus (1895-1909) Identification of the asymptomatic bearer as a critical vector in typhoid, diptheria, polio (1893-1905)

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More Triumphs Of Epidemiology • Cigarette smoking observed to be real reason for lung tumor, emphysema, and cardiovascular ailment (1951-1963). • Eradication of smallpox (1978). • Perinatal Hepatitis B contamination essential reason for hepatocellular carcinoma (commonest growth in China, Southern Africa) (1970-80s). • Identification of the AIDS disorder, forecast that the reason was a sexually-transmitted infection (1981-3), and improvement of aversion measures BEFORE the infection was distinguished.

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Quantifying The Epidemic 1. Case definition 2. Pestilence bend Â·â  point source (normal source, basic vehicle) · engendered 3. Assault Rate 4. Hatching period 5. Crowd invulnerability

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Getting At The Source Mode of transmission Vector Vehicle Reservoir Portal of entry Agent

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Sorting out the MODES OF COMMUNICATION of illness, a large portion of which include vehicles, vectors and supplies, is the region of disease transmission specialists. Just work in the field can reveal the path in which an operators connections to a host in this present reality outside of the lab.

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VEHICLE – A lifeless item which serves to convey sickness. For instance, a glass of water containing microorganisms, or a messy cloth, and so forth. VECTOR – A live life form that serves to convey ailment. For instance, mosquitoes and other arthropods. RESERVOIR – An area that serves as a proceeding with wellspring of ailment – for instance, a water tower (normal in legionella contaminations), the dirt for tetanus, and so forth

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Snow found the waterborne course as a noteworthy method of correspondence of ailment, which ended up applying to cholera , as well as to typhoid fever and different diseases.

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In infection counteractive action, knowing the method of correspondence is by and large more essential than distinguishing the particular operators. (Consider AIDS and SARS for instance). Different courses of transmission were found after Snow ’ s work, particularly arthropod vectors found between 1878 – 1911.

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That period (1878 – 1911) can be seen as the GREAT\'s season VECTOR REVOLUTION. Happening somewhat later than the GREAT BACTERIAL REVOLUTION , it expanded the discoveries of bacteriologists and gave data fundamental to illness control.

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DISCOVERY OF MODES OF TRANSMISSION DIRECT CONTACT FECAL-ORAL ASYMPTOMATIC CARRIER VEHICLE (water) VECTOR (arthropod) (two different methods of transmission were generally perceived by the 19 th century – sexual and airborne)

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MODES OF TRANSMISSION 1. DIRECT CONTACT 1848 – Semmelweis found that puerperal sepsis is transmitted physically from the post-mortem examination space to the conveyance room by specialists.

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MODES OF TRANSMISSION 2. FECAL-ORAL ROUTE 3. WATER AS VEHICLE In 1849 Snow distributed confirmation that cholera is transmitted by the fecal oral course and by the water supply. In the 1850 ’ s, Budd demonstrated that typhoid fever has an indistinguishable transmission design.

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MODES OF TRANSMISSION: 4. THE ASYMPTOMATIC CARRIER 1893 Diphtheria Park and Beebe 1900 Typhoid Reed, Vaughan & Shakespeare 1905 Meningococcus Wechselbaum 1905 Polio Wickman

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1878-1895: Filariasis, Texas Cattle Fever and Sleeping Sickness 1878 - Patrick Manson (UK) found that the larval phase of filaria, which causes filariasis , is found in mosquitoes. 1892 - Smith and Kilbourne (US) found that Texas Cattle Fever is transmitted perinatally by ticks (They additionally recognized the causative babesia creature). 1895 – Bruce (UK) found that African trypanosomias or dozing ailment is transmitted by the chomp of the Tse-tse fly.

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1897-1900: Malaria and Yellow Fever 1897 - Ronald Ross found that jungle fever is transmitted by mosquitoes. Some credit the revelation to the Italian researcher, Grassi.(The French doctor Laveran had disovered the operators, plasmodium, in 1880). 1900 - Walter Reed found that yellow fever is transmitted by mosquitoes. William Gorgas utilizes this data to free Havana of Yellow Fever, and later to do likewise in the channel zone, allowing development of the Panama canal.(The infection was found in the 30 ’ s, by Rivers).

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1906-1909: Plague, Chagas Disease 1906 - The Indian Plague Commission demonstrated that bugs conveyed by rats transmit Plague, however s ome credit the French specialist, Simond, in 1898, with this revelation. (The sickness bacillus had been found by Yersin or Ogata (questioned) in Hong-Kong 1894-1896). 1909 - Chagas found that the trypanosome that causes Chagas malady or American trypanosomiasis is transmitted by parasitic cone-nosed or kissing bugs (reduviidae). (Chagas and Cruz found the particular trypanosome in the meantime).

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1911 - Typhus Charles Nicolle showed that typhus is transmitted by lice. (Rickettsia were found by Ricketts at about the same time).

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The Seven Cholera Pandemics #1. 1817-1823 FIRST AWARENESS Restricted to Asia and Africa #2. 1826-1837 CHOLERA IN EUROPE first European plague in 1831-2. John Snow, as youthful disciple physician, sees cholera cases in Yorkshire.

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The Seven Cholera Pandemics #3. 1846-1862. SNOW FIGURES IT OUT London and New York hit hard in 1848/9 and 1853/4 (more than 10,000 passings in every city in every scourge). Brilliant Square scourge of 1854 leaves 500 dead inside of a 250 yard span of a solitary water pump. Authority Board of Health examination denies waterborne transmission, credits London plague to miasmas emerging from the Thames.

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The Seven Cholera Pandemics #4. 1864-1875 SOME HAVE LEARNT Improved water supply in Great Britain and US extensively brings down mortality in the 1866 plague contrasted with before pestilences. #5. 1881-1896 BUT OTHERS HAVEN ’ T Though Koch had recognized vibrio comma in 1883, Hamburg, under impact of Von Pettenkoffer, who did not have confidence in direct waterborne transmission, encounters 10,000 cholera passings in 1893, from an obviously waterborne source.

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The Seven Cholera Pandemics #6. 1902-1923 QUIET TIME IN US N o scourges in Western Hemisphere. #7. 1961 – present RETURN OF CHOLERA Less extreme El Tor biotype prevails. 1978 -Cholera comes back to North America in with sporadic shellfish-related cases in Louisiana and Texas. 1991 - First plague in South America this century starts in Peru in January 1991, with 360,000 cases in 13 nations as such, for the most part waterborne. 1992 - Major plane importation into Los Angeles f

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