Title: We are Not Alone
1We are Not Alone
2They are in the air we breathe . . .
In our food . . .
On our skin . . .
3-on everything we touch.
4They are . . .
5microorganisms
6What are microorganisms?
(also called microbes)
7Microbes are small living plants or animals most
of which are not visible to the naked eye. Some
microbes cause disease or infection. Many
microbes are good organisms that help keep
balance in the environment and the body.
8What microbes lack in size, they make up in
number.
On the average human, there are about 100
trillion microbes.
9Good vs. Bad Microorganisms Microorganisms
that cause disease (germs) are referred to as
pathogens.
Yeah, Im bad.
10Microorganisms that are harmless or beneficial
are called nonpathogens.
11Most microbes are considered beneficial or
harmless.
87
beneficial organisms
10
Pathogens 3
opportunists
12The role of good microorganisms
Marine freshwater microbes form the basis of
the food chain in oceans, lakes, and rivers.
13Soil microbes help break down wastes.
14 Humans and other animals depend on bacteria in
their intestines for digestion and synthesis of
vitamins including vitamin B (for
metabolism) vitamin K (for blood clotting)
15Microorganisms have many commercial
applications They are used in synthesis of
chemical products such as
acetone
alcohol
enzymes
organic acids
many drugs
16They are used in the food industry for producing
pickles
cheese
vinegar
alcoholic beverages
green olives
bread
yogurt
17Main Classes of Pathogenic Organisms
- Bacteria
- simple one-celled organisms
- At home within climate of human body
- compose largest group of pathogens
- Fungi yeasts molds
- Plant-like organisms that live on dead organic
matter - Grow best in dark, damp places
18- 3) Viruses - smallest microbes
- acellular particles (not a complete cell)
- 4) Protozoa
- one-celled animals often found in decayed
materials contaminated water
- 5) Helminths
- parasitic worms
- caused by larval egg infestations
19 Bacterial Infections
20Tuberculosis
- Tuberculosis (TB) is a potentially serious
infectious disease that mainly affects your
lungs. The bacteria that cause tuberculosis are
spread from one person to another through tiny
droplets released into the air via coughs and
sneezes.
21Medications are the cornerstone of tuberculosis
treatment. But treating TB takes much longer than
treating other types of bacterial infections.
With tuberculosis, you must take antibiotics for
at least six to nine months. The exact drugs and
length of treatment depend on your age, overall
health, possible drug resistance, the form of TB
(latent or active) and the infection's location
in the body.
22Clostridium Difficileaka C-Diff
- a bacterium that can cause symptoms ranging from
diarrhea to life-threatening inflammation of the
colon. - C. difficile bacteria are passed in feces and
spread to food, surfaces and objects when people
who are infected don't wash their hands
thoroughly. The bacteria produce spores that can
persist in a room for weeks or months. If you
touch a surface contaminated with C. difficile,
you may then unknowingly swallow the bacteria. - Your intestines contain millions of bacteria,
many of which help protect your body from
infection. But when you take an antibiotic to
treat an infection, the drug can destroy some of
the normal, helpful bacteria as well as the
bacteria causing the illness. Without enough
healthy bacteria, C. difficile can quickly grow
out of control. - Once established, C. difficile can produce toxins
that attack the lining of the intestine. The
toxins destroy cells and produce patches
(plaques) of inflammatory cells and decaying
cellular debris inside the colon and cause watery
diarrhea.
23Treatment Doctors typically prescribe a 10-day
course of one of the following oral antibiotics
metronidazole (Flagyl), Dificid (fidaxomicin), or
vancomycin (Vancocin). Flagyl is usually tried
first. Improvement usually happens within 72
hours after starting antibiotics, but the
diarrhea may return temporarily. Another round of
antibiotics is needed in about 25 of cases. In
addition to prescribed medications, treatment may
include Probiotics. Available in most drug and
health food stores without a prescription,
probiotics are "good" bacteria that colonize in
the gut and may help keep C. diff. infection from
recurring if taken along with prescribed
medicines. Fluids. Drinking plenty of water and
other fluids or getting intravenous fluids can
help guard against dehydration from
diarrhea. For severe cases they are now using
fecal transplants.
24Necrotizing Fasciitis
25(No Transcript)
26Impetigo
highly contagious bacterial infection
27- Impetigo is a fairly common superficial skin
infection caused by bacteria. It may occur on
normal skin, but the bacteria usually invades at
the site of a skin abrasion, scratch, or insect
bite. - Treatment is with antibiotics.
28Extensive case of impetigo on underarm of baby.
29Fetal Tetanus (note severe muscle contractions)
Due to toxin production as a result of bacterial
infection.
30- Tetanus, also known as lockjaw, is caused by
bacterial spores that have entered a deep wound.
The spores germinate and produce a toxin which
interferes with nerves controlling muscles.
Progressive muscular spasms result. - If muscle spasms develop early and are severe,
chances of recovery are poor. - Prevention through immunization is the best
treatment
31Diphtheria
Note swelling in neck
32- Diphtheria is an acute bacterial infection that
usually attacks the respiratory tract. The
infection occurs by inhalation of airborne
droplets.
33Diphtheria membrane
34Cellulitis An acute bacterial inflammation of
connective tissue.
35- Cellulitis usually occurs with dermatitis, a
fungal infection, or after a skin injury. It may
be accompanied by a fever. - Treatment antibiotics elevation of infected
area application of hot, moist compresses to
site.
36Lymes Disease
hallmark bulls-eye lesion
37- Lyme disease was first diagnosed in New Lyme,
Connecticut as a rare form of arthritis. It is,
however, now known to be a bacterial infection
caused by a spirochete that is present in the
deer tick. The vector (insect that carries the
infection) usually transfers the bacteria by
biting a host (human). - Signs and symptoms usually include papule that
becomes red, warm, and itchy. The lesion may
grow to over 20 inches in diameter it typically
resembles a bulls eye or target. Malaise and
fatigue are constant. There are generally
intermittent episodes of headaches, neck
stillness, fever, chills, achiness. - Treatment is a 10 to 20-day course of
antibiotics.
38Tiny deer tick vector that transmits lymes
disease.
Due to its small size, the deer tick is often
hard to see, making detecting of this vector
difficult.
39Fungal Infections
40Candidiasis Oral Thrush
41- Candida is part of the normal flora of the mouth.
It is an opportunistic infection that is
usually held in check by other organisms and the
immune system. When the immune system is
compromised (chemotherapy, long-term illness,
transplantation, stress, AIDS, etc.), the
infection can occur. - Signs cream-colored patches on tongue, mouth,
and/or throat. - Treatment is with oral antifungal mouth solution
--Nystatin. (Swish Swallow)
42Oral Thrush tongue
43Candidiasis of Skin Typical red, slightly most
lesions.
44- Candidiasis of the skin is characterized by
pruritus (itching) and peeling. This fungal
infection usually occurs in damp moist areas. It
is often seen in folds of skin. The fungi will
spread, producing a fringed irregular edge and
pustules. The individual is subject to soreness,
itching, and peeling of the lesion. Predisposing
factors might include diabetes, antibiotic
therapy, immune deficiency, oral contraceptive
use, cytotoxic drug therpay, and obesity. - Other common manifestations of skin candidiasis
are diaper rash vaginitis.
45Nail Fungus
46- Nail fungi are usually a result of extended
exposure to moisture. (e.g. moisture trapped
under acrylic nails). Nail beds can become red
and swollen. The infected nail is
whitish-yellow and tends to be flaky and soft.
Purulent discharge may be seen from nail bed. - Treatment may include topical and or oral
antifungal medication. Sometimes the nail may be
removed.
47Black Hairy Tongue
48- This fungal infection causes hair-like papillae
on top of tongue to grow. It produces a
condition in which the tongue looks as though it
is covered with hair.
49Cutaneous Fungal Infection Tinea Versicolor
Note hypopigmented fungal lesions
50- The white patches seen on skin are due to
colonies of fungi which prohibit regular
pigmentation. These patches usually have a
slightly raised, velvety texture. - Treatment includes use of an antifungal sulfur
soap which is left on skin overnight for a period
of a month. Topical antifungal ointments may
help.
51Cutaneous Fungal Infection Ringworm
52- Ringworm is due to a parasite, not an actual
worm. The infestation was named after the
characteristic rings seen on the skin. These
rings can grow outward as the infection spreads.
Ringworm is very contagious and may spread
through entire households and from schoolmate to
schoolmate. For a mild infection, treatment is
an over-the-counter antifungal agent.
53Cutaneous Blastomycosis Hand Wrist
54- Blastomycosis is caused by a yeast-like fungus.
Cutaneous blastomyucosis causes nonpruritic
lesions on exposed body parts which may become
raised and reddened and sometimes necrotic.
55Subcutaneous Blastomycosis Manifested by
subcutaneous abscesses in upper chest
56- Cutaneous blastomycosis lesions can disseminate
to bone and cause subcutaneous soft tissue
swelling resulting in tenderness and warmth over
bony lesions. - Treatment with antifungal medication
amphotericin B or fluconazol may be used.
57 Chromomycosis Deep fungal infection with
granulomatous lesions.
58- Chromomycosis is a slowly spreading fungal
infection of the skin and subcutaneous tissues.
It can produce granulomatous lesions on the legs
or arms and may spread to the brain if not
treated. - This type of fungal infection requires a systemic
antifungal agent. The condition is chronic.
59Viral Infections
60Influenza The Flu
61Influenza, or flu, is a respiratory illness that
is caused by a virus. Flu is highly contagious
and is usually spread by the coughs and sneezes
of a person who is infected. Not treated with
Antibiotics!! Tamaflu
62Viral Infection Verruca Vulgaris (Wart)
63- Warts are common, benign viral infections of the
skin caused by the human papillomavirus Some
warts disappear readily with treatment whereas
others necessitate prolonged treatment. - Treatment might include electrodesiccation
(effective for common warts), cryotherapy (useful
for facial or genital warts), acid therapy (not
recommended for areas where perspiration is
heavy)
64Herpes Type I Oral Herpes
65- Herpes type I affects skin and mucous membranes.
It commonly produces cold sores and fever
blisters. Presently, there is no cure for herpes
virus.
66More Oral Herpes
healing stage
67Neonatal Herpes
Premature infant born with classic cigarette
burn pattern of HSV infection.
68- Most cases of herpes simples virus (HSV)
infection occur when infants are contaminated by
the mothers reproductive tract immediately prior
to or during birth. HSV infections can be very
destructive to the fetus or newborn and in some
cases may be fatal.
69Poliomyelitis (also called infantile
paralysis) Note deformed right leg
70- Poliomyelitis is an acute communicable disease
caused by the poliovirus. Polio can range in
severity from inapparent infection to fatal
paralysis. The virus can affect the motor nerve
cells and cause paralysis to various parts of the
body. Only about 10 of infected people develop
identifiable symptoms, and researchers report
that paralysis probably affects fewer than 1 of
those infected with the poliovirus. - Polio was first recognized in 1840 when it became
an epidemic in Norway and Sweden. Outbreaks
became pandemic and the incidence of infection
peaked during the early 1950s. In 1955, Jonas
Salk created the polio vaccine which has
effectively eliminated poliomyelitis.
71Iron Lung used by polio victims
The polio virus could cause muscular paralysis to
the diaphragm and intercostal muscles. When this
happened, breathing was possible only with the
iron lungs.
72Varicella (Chickenpox with oral involvement)
73- Varicella is an airborne infection. Symptoms
include lethargy and raised skin eruptions that
are pruritic (itchy). There are three stages of
the eruptions papules, vesicles, crusted
lesions when vesicles have opened. Chickenpox is
contagious as long as one has lesions. There is
a varicella vaccination which prevents
chickenpox. - Shingles (herpes zoster) is a condition that can
develop in people who have had chickenpox. The
virus becomes dormant in nerve cells and may
later be stimulated and cause painful skin
eruptions along skin supplied by the infected
nerve.
74Measles (rubeola) Rash usually begins on face
and spreads to trunk and extremities.
75- Measles is a very contagious viral infection.
Transmission of rubella is airborne by way of
infected droplets from the nose of mouth. - Signs and Symptoms include high fever, pain of
eyes and sensitivity to light. The most
characteristic sign is a maculopapular rash (red
blotch and tiny bump). Persons are contagious
until the rash is gone. - Vaccination against rubella is effective.
76Mumps Note edema to cheeks and neck
77- Mumps is caused by a virus and spread by
inhalation of infected droplets. Affected
individuals become contagious one day before the
symptoms are apparent. - Symptoms can include swollen, painful salivary
glands which cause the cheeks to puff out,
low-grade fever, lethargy. Mumps is not a
serious disease. It rarely lasts more than two
weeks. In rare instances, encephalitis may
develop. - The mumps vaccine is safe and effective.
78Viral Hepatitis Severely distended abdomen
(ascites). Secondary complication from hepatitis.
79- Hepatitis may become chronic or severe and result
in cirrhosis of the liver and portal
hypertension. As a result of portal
hypertension, excess fluid seeps from the liver
into the abdominal cavity (ascites). Treatment
for ascites might includes diuretics, or
abdominocentesis.
80Parasitic Protozoan Infections
81Leishmaniasis (protozoan systemic
disease) Severe nodular, disfiguring
lesions transmitted by sand fly
82- Leishmaniasis (pronounced lish man-i a-sis) are
transmitted when an infected sandfly bites and
enters the blood of the host. Leishmaniasis is
endemic to most tropical and subtropical
countries.
83Dracunculiasis (Fiery Dragon Worm) Found just
under skin of human host.
Causes blisters at site of infestation.
84- There is a wide geographical distribution of
these dragon worms Asia, Middle East, Arabia,
and North and equatorial Africa). Humans are
generally infested with this parasite by drinking
contaminated water. Once in the human, worms
migrate from intestinal tract via subcutaneous
tissue to the skin where the fertilized female
worms reach maturity and produce juveniles.
(Male worms die after fertilization.) Sores
produced by reproductive female worms result in a
blister. Oftentimes, these sores can be infected
with bacteria, resulting in abscesses.
85Ulceration from worm.
86- Eventually a superficial blister will ulcerate
and the worm is visible. At this point, most
infestations are treated by simply removing
female worm. Typically, the worm is attached to
a small stick and removed by slowly winding the
worm on to the stick. Although this is a
primitive treatment, it is an effective method.
It does not prevent much of the damage caused by
worms nor does this method prevent reinfection.
87A fiery dragon worm emerges from leg.
88Elphantiasis (filariasis)
89- The microscopic larvae of the filarial worm enter
the body through the bite of a mosquito or other
insect. It tends to infest the lymph nodes and
prevent drainage of lymph . This results in
swelling and gross disfiguration of genitals and
legs. These worms are common in most tropic and
subtropic regions. The condition is endemic in
Central Africa and Southern South East Asia.
90Elphantiasis affecting left leg and genitals
91- Worm infection is characterized by occlusion of
lymph vessels. There is swelling and pain of the
limb that is distal to the blockage. After many
years the limb may become grotesquely swollen and
the skin coarse and tough. - Oral medication is available for treatment. The
most effective means of preventing filarial
infestation is mosquito and insect control.
92Intestinal helminthes cause infestations in
intestinal tract and abdominal organs such as the
liver and spleen.
Always in pairs.
93- Treatment for intestinal helminthes generally
consists of taking antiparasitic drugs.
94Helminthes which have infested the
liver. hepatomegaly and ascites
95Intestinal Roundworms
Mass of 800 worms removed from childs ileum
during autopsy
96- The intestinal roundworm, ascaris lumbricoides
(as-kah-ris lum-brih-koy-dees), is a giant
helminth. The ascaris spends its larval and
adult stages in humans. Later, it releases eggs
in human feces, which can be spread to other
humans through food, drink, or soiled items
placed in the mouth. - Treatment consists of taking antiparasitic drugs.
97Loa Loa eye worm infestation in conjunctiva
98- The loa loa is a parasitic worm of western and
central Africa. It is also be referred to as the
eye worm. In this picture, the worm is just
under the conjunctiva of the eye.
99Loa loa being extracted from under conjunctivia.
100Hydatid cyst formed by tiny tapeworm that
migrated to brain.
101- This dangerous tapeworm, Echinococcus granulosus,
lives in the intestinal tract of carnivorous
animals (e.g. dogs, wolves). Humans become
infected from contact with the feces of animals
that had eaten flesh of sheep or deer containing
the cyst form of the tapeworm. This disease is
more commonly seen in people who hunt and trap
wild animals or raise livestock.
102- Summary
- Microbes are microscopic organisms
- About 100 trillion microbes live on the average
human - Bad microbes are pathogens
- About 3 of microorganisms are pathogenic
- Main classes of pathogenic microbes include
bacteria, fungi, viruses, protoza, helminths
103Thats all folks.