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Shoo Fly, Don’t Infect Me! Mechanical Vectors of Bacterial GI Diseases Liz Melton March 9 th , 2012. HUMANITARIAN CRISIS – Mechanical Transmission. Coincides with Vector Habitat/Behavior:. -latrines (human and animal feces) -unsanitary overcrowding -refugee/prisoner of war camps
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Shoo Fly, Don’t Infect Me! Mechanical Vectors of Bacterial GI Diseases Liz Melton March 9th, 2012
HUMANITARIAN CRISIS – Mechanical Transmission Coincides with Vector Habitat/Behavior: -latrines (human and animal feces) -unsanitary overcrowding -refugee/prisoner of war camps -areas with inadequate screening techniques -on dead corpses -unfiltered garbage composts www.un.org/millenniumgoals/pdf/mdg2007.pdf
What is Mechanical Transmission? “a form of indirecttransmission in which the infectious agent does not undergo physiologic changes inside the vector” (CDC definition) Examples: *fly-borne cockroach-borne coprophagic beetle-borne Hinshaw, J. (Photographer). (2000). [Photograph]. Retrieved February 13, 2012, from: http://www.worldwidewounds.com/2000/oct/Janet-Hinshaw/Larval-Therapy-Human-and-Veterinary.html.
Common Mechanical Vectors • House Flies • Filth Flies • Blowfly • Cockroaches Orangeacid. (Photographer). [Photograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/orangeacid/189512184/sizes/z/in/photostream/. Keiding J. The housefly—biology and control. Training and information guide (advanced level). Geneva, World Health Organization, 1986 (unpublished document WHO/VBC/ 86.937; available on request from Division of Control of Tropical Diseases, World Health Organization, 1211 Geneva 27, Switzerland). Lerlind. (Photographer). [Photograph] Retrieved February 13, 2012, from: http://www.flickr.com/photos/lerlind/3520284423/sizes/z/in/photostream/.
Characteristics: • Common Cockroach -5-73 mm in length -2 pair of wings -flattened appearance -yellow/brown color -agile -exhibits endophagic behavior -active at night, in latrines *RESPONSIBLE FOR: Diarrheal diseases Typhoid fever Dysentery Hinshaw, J. (Photographer). (2000). [Photograph]. Retrieved February 13, 2012, from: http://www.worldwidewounds.com/2000/oct/Janet-Hinshaw/Larval-Therapy-Human-and-Veterinary.html.
Egypt Scenario “The role of cockroaches and flies in mechanical transmission of medically important parasites” Journal of Entomology and Nematology, Gehad T. El-Sherbiniand Eman T. El-Sherbini, 2011 • METHODS: • Surveyed residential areas in KhaldyiaVillage, Egypt 2009 – 2010 • 45 cockroaches collected in control, 178 total collected • Flies from human feces also observed • Parasites isolated/identified from defecation areas in and around houses (Photograph). [Photograph]. Retrieved February 13, 2012, from: http://www.cockroachesextermination.info/?f.
Egypt Scenario • RESULTS: • -Cockroaches trapped in the toilets of: • houses with pit latrines: 98 parasites/ml • houses with water system: 31 parasites/ml • -Pathogens isolated from external and internal surface of 98% of test cockroaches Ric_k. (Photographer). [Photograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/ric_k/3196975264/sizes/z/in/photostream/.
Thailand Scenario “THE MAJORITY OF COCKROACHES FROM THE SAMUTPRAKARN PROVINCE OF THAILAND ARE CARRIERS OF PARASITIC ORGANISMS” PennapaChamavit, PanupongSahaisook, NunthawadeeNiamnuy, EXCLI Journal 2011 • METHODS: • 920 cockroachesobtained in Samutprakarn province of Thailand • 18 open-air shopping markets in 5 districts, 1 subdistrict • captured during feeding, natural habitat • Conducted wet smear/modified acid-fast bacilli staining identified pathogens Corbie. (Photographer). [Photograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/crow/401136434/sizes/l/in/photostream/.
Thailand Scenario • RESULTS: • -498/920 (54.1%)of the cockroaches harbored parasitic organisms • **Cockroaches isolated from these markets are carriers of several organisms: • cause commonly found symptoms of illness such as diarrhea or bowel disorder Gusthed. (Photographer). [Photograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/bokage/5570904814/.
Flies as Mechanical Vectors **350 fly species in 29 familiesareassociated with food-borne diseases** > 50 species of synanthropic flies correlated with unsanitary conditions 21 species of filth fliestransmit human gastrointestinal diseases ALL disseminate human pathogens in the environment breed in: animal manure human excrement garbage animal bedding decaying organic matter UNICEF Bangladesh. (Photographer). [Photograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/unicefbangladesh/6791300900/sizes/z/in/photostream/.
Characteristics: • Muscadomestica -6-7 mm long, grey color -marked by 4 dark longitudinal stripes -breed in animal/human excrement or domestic organic waste -land, breed, and feed on feces and human food • *RESPONSIBLE FOR: • Infantile diarrhea • Shigellosis diarrhea • Dysentery • Typhoid
Indian Housefly Scenario “Vector potential of houseflies (Muscadomestica) in the transmission of Vibriocholerae in India” R. Fotedar, ActaTropica, 2001 • METHODS: • Small village 15 km away from Delhi city outbreak of diarrhea • 150 houseflies captured with sterilized nets from animal pens, yards or houses • Collect stool samples from 50 patients within 24 hrs of illness, before anti-microbial Praline 3001. (Photographer). [Photograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/praline3001/6672614287/sizes/l/in/photostream/ .
Indian Housefly Scenario • RESULTS: • -60% fly pools were positive for V. cholerae • -during outbreak: V. cholerae Ogawa T2 El Tor isolated from stools of patients suffering from diarrhoea • **Houseflies act as mechanical vectors of V. cholerae biotype El Tor, and aid in dissemination Medicinssansfrontieres. (Photographer). [Photograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/medecinssansfrontieres/3085562538/sizes/z/in/photostream/.
Hospital Housefly Scenario The housefly (Muscadomestica) as a carrier of pathogenic microorganisms in a hospital environment R. Fotedar, U. Banerjee,, S. Singh, Shriniwas and A. K. Verma, Journal of Hospital Infection, 1992 • METHODS: • Collect Muscadomesticafrom: • surgical ward (All India Institute of Medical Sciences Hospital) • remote residential area 5 km away as a control • A total of 113 flies were collected: • 65 from a surgical ward (test) • 48 from a residential area (comparison) Gusthed. (Photographer). [Photograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/bokage/5521594305/sizes/l/in/photostream/.
Hospital Housefly Scenario RESULTS: -10 genera of bacteria isolated from the test group, 9 from control group -the load of bacteria carried by the test group of flies was significantly more **House flies therefore may act as vectors of potentially pathogenic bacteria in a hospital environment. Cardiff Biossi Imaging. (Photographer). [Photograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/biosi-imaging/5517090693/sizes/l/in/photostream/.
Characteristics: • Muscasorbens -resides in tropical areas -breed in human feces -feed on the secretion produced by eyes of people, especially children. -6 mm long, grey -2 dark stripes on the thorax. • *RESPONSIBLE FOR: • diarrheal diseases • transmission of the eye disease trachoma
Chrysomya spp. Characteristics: -worldwide distribution -breeds in open latrines, garbage, animal excrement -compact body, measuring 10 mm -shiny blue or green • *RESPONSIBLE FOR: • Diarrheal diseases • Dysentery • Intestinal worm eggs
Fly Life Cycle MANTRA: “food, feces, flies, feces” Sir Richard Feachem, KBE, FREng, DSc(Med), PhD, Director, The Global Health Group, Professor of Global Health UCSF Four Stages: Egg Maggot Pupa Adult Photograph by: Jim Kalisch, University of Nebraska – Lincoln Photograph by: Jerry F. Butler, University of Florida Photograph by: Jim Kalisch, University of Nebraska - Lincoln
Mechanical Transmission Process “feces enhances transmission of infectious agents muchgreater than that of any other substrate or medium” • Dislodgement onto Food • electrostatic charge • 2) Fecal Deposits • without changing infectivity • increased viscosity of feces • 3) Airborne Particles • electrocution traps • further spread of infectious particles Iwork2travel1. (Photographer). [Photograph]. Retrieved February 13, 2012, from: fhttp://www.flickr.com/photos/72457981@N00/353447863/sizes/l/in/photostream/.
“Super” Transmitters • Carry Pathogens on: • spongy mouthparts • body and leg hairs (setae) • sticky substance • adherence during fly resting periods • sticky pads of the feet (tarsi) PKMousie. (Photographer). [Photograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/pkmousie/2618446877/sizes/l/in/photostream/. Jatin.muddu. (Photograher). [Photograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/jatinmuddu/2374306028/sizes/l/in/photostream/.
“Filthy Flies”– U of F insect pathologist, Dr. Jim Maruniak http://www.youtube.com/watch?v=hMcf9C-iqJc
Results of Transmission • Major spread ofbacterial enteric disease agents: • 1) Inflammation of the gut • 2) Diarrhea • And parasitic disease agents: • -Sarcocystisspp • -Toxoplasmagondii • -Isosporaspp. • -Giardiaspp. • -Entamoebacoli • -Entamoebahistolytica/Entamoebadispar • -Endolimaxnana • -Pentatrichomonashominis • -Hammondiaspp. • -Cryptosporidium parvum RachSilvester. (Photographer). [Photograph]. Retrieved fFebruary 13, 2012, from: http://www.flickr.com/photos/rachsilvester/6155801573/sizes/m/in/photostream/. Rubber Slippers in Italy. (Photographer). [Photograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/rubber_slippers_in_italy/5997107603/sizes/z/in/photostream/.
Mechanically Transmitted GI Diseases • Salmonella • Typhoid • Bacillary Dysentery (Shigellosis) Gusthead. (Photographer). [Photograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/bokage/5570316311/sizes/l/in/photostream/.
Signs and Symptoms • Salmonella Who is affected: -elderly -children 12 – 72 Hr Presentation (lasts 4 – 7 days): -diarrhea May require hospitalization Can be fatal -fever -abdominal cramps Can Develop: -Reiter’s Syndrome Treatment: -antibiotics NIAID_Flickr. (Photographer). [Photograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/niaid/5613656967/.
Signs and Symptoms • Typhoid - Salmonella Typhi -un-industrialized nations Asia Africa Latin America Presentation: -sustained fever (103° to 104° F) -stomach pains -headache Result of : -International travel -Food/water contamination Treatment: -antibiotics Sanofi Pasteur. (Photographer). [Photograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/sanofi-pasteur/5279772517/.
Signs and Symptoms • Bacillary Dysentery - Shigellosis Location: -distributed worldwide Presentation (lasts 5 - 7 days): -diarrhea (bloody) -fever -stomach cramps Can Develop: -chronic arthritis Treatment: -antibiotics (Bactrim, Septra, Rocephin) -anti-diarrheals (Imodium) Nathan Reading. (Photographer). [Photograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/nathanreading/6808291881/.
Historical Significance Wartime Effects -1992-93, relief forces in Somalia faced huge fly problems -Operation Enduring Freedom and Operation Iraqi Freedom: camps placed in midst of unsecure population centers -WWI: strong correlation between fly density and the incidence of dysentery -WWII battle of El Alamein: Axis losses due to dysentery -Monumental nuisance during the Vietnam War -Similar problems were encountered in the Persian Gulf War of 1991/subsequent humanitarian relief operations http://www.defense.gov/multimedia/web_graphics/dod/DODc.jpg, http://www.defense.gov/multimedia/web_graphics/army/USARVc1.jpg, http://www.defense.gov/multimedia/web_graphics/navy/USNc.jpg: Courtesy of U.S. Dept of Defense
Sample Wartime Precautions Armed Forces Pest Management Board: • Fly - Associated Diseases in Somalia: • ENTERIC DISEASES • AGENTS: a variety of organisms, primarily bacteria and protozoa. • VECTOR TRANSMISSION: Fecal-oral • -house flies and other filth flies are implicated in amplifying outbreaks • house fly, Muscadomestica • filth flies, M. sorbensand M. biseta • -Cockroaches may also serve as mechanical vectors • Disease Vector Ecology Profiles (DVEPs) and TECHNICAL GUIDE NO. 30 - Filth Flies • Significance, Surveillance and Control in Contingency Operations: • EMPHASIS: • -essential epidemiology • -vector bionomics/behavior • -pesticide resistance Example
Primary Reduction Example “Reduction of transmission of shigellosis by control of houseflies (Muscadomestica)” Dani Cohen, et. al, The Lancet, 1991 • Prospective Crossover Intervention Study • METHODS: • 2 military field bases several km apart in early summer, 1988 • 2) Implement and track progress of intensive fly control measures at one base, keep another as control US Army Africa. (Photographer). [Phorograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/usarmyafrica/4325510666/sizes/l/in/photostream/.
Primary Reduction Example • RESULTS: • -after 11 weeks, fly counts were 64% lower on the bases exposed to fly control • **Clinic visits for diarrheal diseases dropped by 42%: • 85% for shigellosis (76% for antibodies to Shigella) • 57% for antibodies to enterotoxigenic Escherichia coli IFRC. (Photographer). [Photograph]. Retrieved February 13, 2012, from: http://www.flickr.com/photos/ifrc/6152296211/sizes/l/in/photostream/.
Preventative Measures • 4 Main Goals: • 1) reduction or elimination of fly breeding sites • 2) reduction of sources that attract flies from other areas • 3) prevention of contact between flies and disease-causing germs • 4) protection of food, eating utensils and people from contact with flies. • "zero fly" tarps • insecticide • new technology (WHO) shelter Keiding J. The housefly—biology and control. Training and information guide (advanced level). Geneva, World Health Organization, 1986 (unpublished document WHO/VBC/ 86.937; available on request from Division of Control of Tropical Diseases, World Health Organization, 1211 Geneva 27, Switzerland).
PATH & WaterAid America “Defeating a Global Killer: The Need for Action on Diarrheal Disease, a discussion of a growing global health crisis that receives little attention and what we can do about it” (May, 2009). Defeating a Global Killer: The Need for Action on Diarrheal Disease. www.who.int/entity/pmnch/events/2009/InvitationDDevent.pdf. [Flyer]. February 13, 2012. • **Diarrheal disease is the 2nd killer of children • 2 leading NGOs explore steps toward stopping deaths owing to diarrheal diseases internationally: • adequate resources • effective implementation of available health • clean water • sanitation solutions