Transcript Communicable Disease Health Grade 8

Communicable Disease
Health
Grade 8
Communicable Disease
• Disease- Condition that interferes with the
operation of the body and/or mind
• Diseases that can be passed to a person
from another person, animal, or object.
• Tiny organisms that cause communicable
diseases are called pathogens.
5 Types of Pathogens
• Bacteria
Bacteria
• Bacteria are tiny one celled organisms that
live nearly everywhere.
• Most are harmless
• Many live on and inside the body
• The body needs certain bacteria to work
properly
• Common diseases caused by bacteriastrep throat, pneumonia, tooth decay,
impetigo, lyme disease, tuberculosis
Bacteria
• Most bacteria reproduce by growing and
dividing into two cells in a process known
as binary fission
Strep Throat
5 Types of Pathogens
• Viruses
Viruses
• Viruses are the smallest disease-causing
pathogens
• Viruses, however, are not organisms
themselves because, apart from a host
cell, they have no metabolism and cannot
reproduce
• Viruses can not be treated with antibiotics
• Common viruses include colds, flu,
measles, mumps, chicken pox, hepatitis
Viruses
5 Types of Pathogens
• Fungi
Fungi
• Primitive life forms that feed on organic
material
• Certain fungi live in hair, nails, and skin
• Fungi causes ringworm, athlete’s foot
• Together with bacteria, fungi fulfill the
indispensable role of ‘decomposers’ in the
environment
• Protozoa are a group of microscopic one-celled animals.
• Protozoa can be parasites or predators.
• In humans, protozoa usually cause disease.
– Malaria is caused by a protozoan parasite.
– Toxoplasmosis is a troubling protozoan infection especially for
pregnant women and for people with HIV or other immune
deficiency.
• Some protozoa, like plankton, live in water environments
and serve as food for marine animals, such as some
species of whales.
• Protozoa also can be found on land in decaying matter
and in soil, but they must have a moist environment to
survive.
5 Types of Pathogens
• Protozoa
Protozoa
• Usually harmless, but can cause certain
diseases.
• Malaria is a disease caused by protozoa
that live in certain kinds of mosquitoes.
• If infected mosquito bites human, person
will become infected.
• Water contaminated with protozoa can
also cause infections.
Protozoa
• Diarrheal disease in the United States can
be caused by two common protozoan
parasites, Giardia lamblia and
Cryptosporidium parvum
5 Types of Pathogens
• Rickettsias
Rickettsias
• Disease causing organisms that resemble
bacteria, but multiply like viruses.
• Enter humans from the bites of insects
such as fleas or lice.
• Cause typhus or Rocky Mountain spotted
fever.
Pathogens
• Pathogens are spread by direct or indirect
contact with an infected person, vector, or
contact with water or food that contains
pathogens.
A vector is an organism, such as an
insect, that transmits a pathogen.
How pathogens are spread
• Sickness occurs when a pathogen enters
the body.
• 4 ways of transmission
– Direct contact with infected person
– Indirect contact with infected person
– Contact with vector
– Other contacts (drinking water, eating food)
Direct Contact
• Picking up pathogens from an infected
person
• Examples: kissing someone with strep
throat, sexual encounters with someone
infected with HIV
Indirect Contact
• Pathogens are spread through the air
• Sharing utensils or drinking from same
glass as infected person
Vector
• A vector such as an insect like mosquito or
flea
• Mosquito spreads malaria
• Tick spreads Lyme disease, Rocky
Mountian spotted fever
Other Contacts
• Water or food
• Improperly stored food or undercooked
meat is dangerous for this reason
• Blood born- receiving blood that carries
pathogens
Preventing the spread of disease
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1. Good hygiene- Wash hands
2. Wear suitable clothing while outdoors
3. Avoiding contact with an infected person
4.Get vaccinated
5. Cover mouth, nose when coughing or
sneezing
Handwashing
• See video www.discoveryeducation.com
• A study by the University of Arizona in
2002 found that a desk has hundreds of
times more bacteria per square inch than
an office toilet seat.
• Desks, phones and other private surfaces
are also prime habitats for the viruses that
cause colds and flu.
Did You Know?
• Office toilet seats had 49 germs per square inch, he
found. But desktops had almost 21,000 germs per
square inch. Phones were worse -- more than 25,000
germs per square inch.
• Desks, phones, computer keyboards and mice are key
germ transfer points because people touch them so
often, Gerba said, adding that coughing and sneezing
can leave behind "a minefield of viruses" that can live on
a surface for up to three days. But health experts say
that simple office hygiene can reduce infection risks
dramatically.
• "We know that 80 percent of the infections you get are
transmitted through the environment," Gerba said.
Facts
• Wiping down work areas with disinfectant wipes every
day reduces bacteria significantly, Gerba said.
• "Nobody ever cleans a desktop until they start sticking to
it, from what we've found," he said. "A lot of people eat
and slop on their desks all the time so it basically turns
into a bacteria cafeteria during the day, and that's one of
the reasons you get a lot on your desktops."
• Roslyn Stone, chairwoman of the Centers for Disease
Control and Prevention's Workplace Flu Prevention
Group, had another low-tech recommendation -washing your hands.
• "Soap and hot water for 18 to 20 seconds as frequently
as you can remember to do it is going to be your single
most effective prevention tip this season," she said.
Contagious Period
• The length of time when a particular
disease can spread from person to person
• Stay home from school and away from
people during this period
Contagious Period
• How long is a person with flu virus
contagious?
• The period when an infected person is
contagious depends on the age and health of
the person. Studies show that most healthy
adults may be able to infect others from 1 day
prior to becoming sick and for 5 days after they
first develop symptoms. Some young children
with weakened immune systems may be
contagious for longer than a week.