Dis-ease

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Dis-ease

• May you live long, share much kindness, and
  always talk nicely to yourself

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Bacteria
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Bacteria grow in a wide variety of habitats and
conditions.

• When most people think of bacteria, they think of
  disease-causing organisms, like the Streptococcus
  bacteria growing in culture in this picture,
  which were isolated from a man with strep throat.
  
• While pathogenic bacteria are notorious for such
  diseases as cholera, tuberculosis, and gonorrhea,
  such disease-causing species are a comparatively
  tiny fraction of the bacteria as a whole.
• Bacteria are so widespread that it is possible
  only to make the most general statements about
  their life history and ecology.
• They may be found on the tops of mountains,
• The bottom of the deepest oceans,
• In the guts of animals, and even
• In the frozen rocks and ice of Antarctica.
• One feature that has enabled them to spread so
  far, and last so long is their ability to go
  dormant for an extended period (forming capsides
  to prevent desiccation or hard-coated materials
  creating a bacterial spore.

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Virus
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Viruses

• Viruses are particles of nucleic acid, protein,
  and some cases lipids that can reproduce only by
  infecting living cells.
• A typical virus is composed of a core of either
  DNA or RNA, surrounded by a protein coat.
• A viruss outer protein coat is called its
  capsid.
• The capsid includes protein that enables a virus
  to enter a host cell.
• The capsid proteins of a typical virus bind to
  the surface of a cell and trick the cell into
  allowing it inside.
• Once inside, the viral genes take over,
  eventually.
• The cell transcribes the viral genes, putting the
  genetic program of the virus into effect.
• The virus may become part of the hosts genome
• Sometimes that genetic program may simply cause
  the cell to make copies of the virus, but often
  it destroys the host cell.

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Pathogen Type Disease Agent that Causes Disease Methods of Transmission
Viruses Common Cold Rhinovirus Airborne, direct contact with infected person
Viruses Influenza Two types (A,B), plus subtypes
Viruses Chicken Pox Varicella Herpes virus Airborne, direct contact with infected person
Viruses Measles Paramyxovirus Airborne, direct contact with infected person
Viruses Acquired Immune Deficiency Syndrome Human Immune-deficiency Virus Body fluids Direct sexual contact
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Pathogen Type Disease Agent that Causes Disease Methods of Transmission
Bacteria Tuberculosis Mycobacterium tuberculosis Droplets in air, direct contact with secretions of infected person
Bacteria Meningitis Neisseria meningitides Direct contact with a carrier
Bacteria Cholera Vibrio cholerae Contaminated drinking water
Bacteria Tetanus Clostridium tentani Contaminated wound, usually puncture wound
Protists African sleeping sickness Trypanosoma Spread by tsetse fly
Protists Malaria Plasmodium Spread by Anopheles mosquitoes
Protists Amoebic dysentery Entamoeba histolytica Contaminated drinking water
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Malaria Infection
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One more reason to hate mosquitoes
Roll down your sleeves to cover exposed skin and avoid mosquito bites, especially in evening and early morning.

• West Nile Virus

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CNS infecting virus West Nile Virus
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Human Disease Cases by County - California, 2004
Butte County - 7 Fresno County- 11 Glenn County
- 3 Imperial County - 1 Kern County - 59 Lake
County - 1 Lassen County - 1 Los Angeles County -
305 Merced County - 1 Orange County - 62 Placer
County - 1 Riverside County - 109 Sacramento
County - 3 San Bernardino County - 187 San Diego
County - 2 San Joaquin County - 2 San Luis Obispo
County - 1 Santa Clara County - 1 Shasta County -
5 Tehama County - 10 Tulare County - 3 Ventura
County - 2 Yolo County - 1

• Cumulative 2004 Data as of 3 am, Apr 30, 2005

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West Nile Virus is transmitted to humans through
mosquito bites. Mosquitoes become infected when
they feed on infected birds that have high levels
of West Nile Virus in their blood. Infected
mosquitoes can then transmit West Nile Virus when
they feed on humans or other animals.Since West
Nile virus (WNV) was first isolated in 1937, it
has been known to cause asymptomatic infection
and fevers in humans in Africa, West Asia, and
the Middle East.
These data are provisional and may be revised or
adjusted in the future.
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More about the dreaded WNV

• Human and animal infections were not documented
  in the Western Hemisphere until the 1999 outbreak
  in the New York City metropolitan area. Since
  then, the disease has spread across the United
  States. In 2003, WNV activity occurred in 46
  states and caused illness in over 9,800 people.
• Less than 1 of infected people develop severe
  illness that includes meningitis (inflammation of
  one of the membranes covering the brain and
  spinal cord) or encephalitis.
• The symptoms of these illnesses can include
  headache, high fever, neck stiffness, stupor,
  disorientation, coma, tremors, convulsions,
  muscle weakness, and paralysis. Of the few people
  that develop encephalitis, a small proportion die
  but, overall, this is estimated to occur in less
  than 1 out of 1000 infections.

2004 West Nile Virus Activity in the United
States(reported as of January 11, 2005)
State Neuroinvasive disease Fever Other Clinical/Unspecified Other Clinical/Unspecified Other Clinical/Unspecified Total Human Cases Reported to CDC Total Human Cases Reported to CDC Deaths
California 156 269 269 346 771 771 23 23
Total   900 1017 1017 553 2470 2470 88 88
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Polio

• And we thought it was over

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Thanks for the cartoon

• http//www.pbs.org/wgbh/aso/ontheedge/polio/