Tuberculosis (TB)
Name of Infectious Agent
Mycobacterium tuberculosis
Type of Infectious Agent
Bacteria
Symptoms of Disease
The symptoms of TB disease depend on where in the body the
bacteria are growing. Usually, TB bacteria grow in the lungs where
they cause a bad cough that lasts 3 weeks or longer, pain in the
chest, and coughing up blood or the phlegm from deep inside the
lungs. Other symptoms include weakness, fatigue, weight loss, no
appetite, chills, fever, and sweating at night.
Skin test, blood test, chest X-ray, and sputum culture.
Diagnosis of Disease
Transmission of Disease
TB is spread through the air from one person to another. The TB
bacteria are put into the air when a person with TB disease of the
lungs or throat coughs, sneezes, speaks, or sings. People nearby
may breathe in these bacteria and become infected.
Treatment of Disease
Antibiotic treatment with isoniazid (INH), rifampin (RIF), or
rifapentine (RPT).
Ascariasis
Name of Infectious Agent
Ascariasis worm
Type of Infectious Agent
Helminth
Symptoms of Disease
After the ascariasis eggs are ingested, they hatch in the intestines
and sometimes migrate through the bloodstream or lymphatic
system into the lungs. An intestinal infection can cause abdominal
pain, nausea and vomiting, diarrhea or blood stools, and/or fatigue.
A lung infection can cause persistent cough, shortness of breath,
and/or wheezing.
Diagnosis of Disease
Infection is identified by stool tests, blood tests, and/or imaging
tests.
Transmission of Disease
A person must come into contact with soil mixed with human feces
that contains ascariasis eggs.
Treatment of Disease
Administration of anti-parasite medications.
Common Cold
Name of Infectious Agent
Rhinovirus
Type of Infectious Agent
Virus
Symptoms of Disease
Symptoms include: runny or stuffy nose, itchy or sore throat, cough,
congestion, slight body aches or a mild headache, sneezing, watery
eyes, a low-grade fever, and mild fatigue.
Diagnosis of Disease
Physical examination.
Transmission of Disease
The virus enters your body through your mouth or nose. The virus
can spread through droplets in the air when someone who is sick
coughs, sneezes, or talks. But it also spreads by hand-to-hand
contact with someone who has a cold or by using shared objects,
such as utensils, towels, toys, or telephones. If you touch your eyes,
nose, or mouth after such contact or exposure, you're likely to
"catch" a cold.
Treatment of Disease
There is no cure for the common cold. Over-the-counter cold
treatments do not treat the cold but can sometimes relieve
symptoms. These include pain relievers, decongestants, and cough
syrups.
Flu
Name of Infectious Agent
Influenza
Type of Infectious Agent
Virus
Symptoms of Disease
Symptoms include fever, aching muscles (especially in the back,
arms, and legs), chills and sweats, headache, dry cough, fatigue
and weakness, and nasal congestion.
Diagnosis of Disease
Physical examination.
Transmission of Disease
Flu viruses travel through the air in droplets when someone with the
infection coughs, sneezes, or talks. You can inhale the droplets
directly, or you can pick up the germs from an object — such as a
telephone or computer keyboard — and then transfer them to your
eyes, nose, or mouth.
Treatment of Disease
Bed rest and hydration is usually the only treatment needed.
Antiviral medications can be prescribed if taken soon after
symptoms begin. These drugs may shorten the illness by a day or
so and help prevent serious complications.
Strep Throat
Name of Infectious Agent
Streptococcus pyogenes
Type of Infectious Agent
Bacteria
Symptoms of Disease
General symptoms include throat pain, difficulty swallowing, red and
swollen tonsils that often have white patches or streaks of pus on
them, tiny red spots on the soft or hard palate, swollen and tender
lymph nodes in the neck, fever, headache, rash, and fatigue.
Diagnosis of Disease
Throat culture, rapid antigen test, and/or rapid DNA test.
Transmission of Disease
Streptococcal bacteria are highly contagious. They can spread
through airborne droplets when someone with the infection coughs
or sneezes, or through shared food or drinks. You can also pick up
the bacteria from a doorknob or other surface and transfer them to
your nose or mouth.
Treatment of Disease
Oral antibiotic treatment with penicillin, amoxicillin, erythromycin, or
azithromycin.
Malaria
Name of Infectious Agent
Plasmodium parasite
Type of Infectious Agent
Protozoa
Symptoms of Disease
Malaria causes damage to red blood cells which can cause serious
and sometimes fatal complications. The disease is characterized by
recurrent attacks with moderate to severe shaking chills, high fever,
profuse sweating as the body temperature falls, headache, nausea,
vomiting, and diarrhea.
Diagnosis of Disease
Blood test for the parasite.
Transmission of Disease
Microscopic parasites transmit the disease from person to person. A
mosquito becomes infected by feeding on a person who has malaria
and then transmits the malaria parasites to the next person the
mosquito bites. Malaria can also be transmitted from mother to
unborn child, through infected blood transfusions, and by sharing
infected needles.
Treatment of Disease
Administration of antimalarial drugs.
Trichinosis
Name of Infectious Agent
Trichinella roundworm
Type of Infectious Agent
Helminth
Symptoms of Disease
When a person swallows trichinella larvae encased in a cyst, the
digestive juices dissolve the cyst, releasing the parasite into the
body. The larvae then penetrate the intestine, where they mature
into adult worms and mate. At this stage, symptoms include
diarrhea, abdominal cramps, and malaise. Later the adult female
worms produce larvae that penetrate the intestinal wall, enter the
bloodstream, and burrow into muscle or other tissue. This causes
high fever, muscle pain and tenderness, swelling of the eyelids or
face, weakness, headache, and sensitivity to light.
Diagnosis of Disease
Initial diagnosis relies on physical examination of the classic signs
and symptoms, blood samples, and a muscle biopsy.
Transmission of Disease
People get trichinosis when they eat undercooked meat — such as
pork, bear, walrus, or horse — that is infected with the immature
form (larvae) of the trichinella roundworm.
Treatment of Disease
Administration of anti-parasite (anti-helminthic) medication.
Rotavirus
Name of Infectious Agent
Rotavirus
Type of Infectious Agent
Virus
Symptoms of Disease
Symptoms begin with a fever, followed by three to eight days of
watery diarrhea and vomiting. The infection can cause abdominal
pain as well. In adults who are otherwise healthy, a rotavirus
infection may cause only mild signs and symptoms — or none at all.
Diagnosis of Disease
Diagnosed via a physical exam. Stool sample may be analyzed to
confirm the diagnosis.
Transmission of Disease
Rotavirus is present in an infected person's stool several days
before symptoms appear and for up to 10 days after symptoms
subside. The virus spreads easily through hand-to-mouth contact
throughout this time — even if the infected person doesn't have
symptoms. Not washing your hands after using the toilet or
changing a child’s diaper can cause the virus to spread to anything
you touch, including food, toys, and utensils. If another person
touches your unwashed hands or a contaminated object and then
touches his or her mouth, an infection may follow. Sometimes
rotavirus spreads through contaminated water or infected
respiratory droplets coughed or sneezed into the air.
Treatment of Disease
There is no treatment for a rotavirus infection. The infection usually
resolves within three to eight days. Primary treatment involves the
prevention of dehydration.
Giardiasis
Name of Infectious Agent
Giardia lamblia parasite
Type of Infectious Agent
Protozoa
Symptoms of Disease
A gastrointestinal disease with water, sometimes foul-smelling
diarrhea that may alternate with soft, greasy stools, fatigue,
abdominal cramps and bloating, belching gas with a bad taste,
nausea, and weight loss.
Diagnosis of Disease
The infection is diagnosed with a stool sample.
Transmission of Disease
Giardia parasites live in the intestines of people and animals. Before
the microscopic parasites are passed in stool, they become
encased within hard shells called cysts, which allows them to
survive outside the intestines for months. Once inside a host, the
cysts dissolve and the parasites are released. Infection occurs when
you accidentally ingest the parasites. This can occur by swallowing
contaminated water, by eating contaminated food, or through
person-to-person contact.
Treatment of Disease
Administration of medications specific to giardia infection (including
metronidazole, tinidazole, nitazoxanide, and paromomycin).
Histoplasmosis
Name of Infectious Agent
Histoplasma capsulatum
Type of Infectious Agent
Fungus
Symptoms of Disease
Several types of histoplasmosis exist. The mildest form produces no
signs or symptoms, but severe infections can be life-threatening.
Symptoms of the infection include fever, chills, headache, muscle
aches, dry cough, and chest discomfort. Sometimes the infection
causes joint pain and a rash.
Diagnosis of Disease
Inspection of lung secretions, blood or urine, biopsied lung tissue,
and/or bone marrow.
Transmission of Disease
Histoplasmosis is caused by the reproductive cells (spores) of the
fungus. The histoplasmosis fungus thrives in damp soil that's rich in
organic material, especially the droppings from birds and bats The
spores are extremely light and float into the air when dirt or other
contaminated material is disturbed, so infection is most commonly
transmitted during cleanup or demolition projects and to farmers and
landscapers.
Treatment of Disease
Treatment usually isn't necessary if you have a mild case of
histoplasmosis. But if your symptoms are severe or if you have the
chronic or disseminated forms of the disease, you'll likely need
treatment with one or more antifungal drugs.
Syphilis
Name of Infectious Agent
Treponema pallidum
Type of Infectious Agent
Bacteria
Symptoms of Disease
Primary syphilis – small sore on genitals
Secondary syphilis – Rash that begins on trunk and covers entire
body and may be accompanied by wart-like sores in the mouth or
gential area. Muscle aches, fever, sore throat and swollen lymph
nodes are also common.
Latent syphilis – No symptoms
Tertiary or late syphilis – Brain, nerve, eye, heart, blood vessel,
liver, bone, and joint damage.
Diagnosis of Disease
Blood test for presence of antibodies, fluid culture from sores, or
spinal tap.
Transmission of Disease
Spread through contact with an infected person's sore during sexual
activity. The bacteria enter your body through minor cuts or
abrasions in your skin or mucous membranes. Syphilis is
contagious during its primary and secondary stages, and sometimes
in the early latent period. It is also spread through direct unprotected
close contact with an active lesion or through an infected mother to
her baby during pregnancy or childbirth.
Treatment of Disease
Antibiotic treatment with penicillin.
Ringworm (Tinea corporis)
Name of Infectious Agent
Dermatophytes
Type of Infectious Agent
Fungus
Symptoms of Disease
A circular rash on the skin that’s red and inflamed around the edge
and healthy looking in the middle; slightly raised expanding rings of
red, scaly skin on the trunk or face; and/or a round, flat patch of
itchy skin.
Diagnosis of Disease
Skin scrapings or samples from the infected area are taken and
looked at under a microscope.
Transmission of Disease
Ringworm is contagious and can be spread in the following ways:
direct, skin-to-skin contact with an infected person; touching an
animal with ringworm; contact with objects or surfaces that an
infected person or animal has recently touched or rubbed against; or
contact with infected soil.
Treatment of Disease
Administration of a prescription-strength topical antifungal or oral
medication.
Tapeworm
Name of Infectious Agent
Tapeworm
Type of Infectious Agent
Helminth
Symptoms of Disease
Intestinal infections cause nausea, weakness, loss of appetite,
abdominal pain, diarrhea, weight loss and inadequate absorption of
nutrients from food. Invasive infections result in fever, cystic masses
or lumps, allergic reactions to the larvae, bacterial infections, and
neurological symptoms including seizures.
Diagnosis of Disease
Stool sample analysis, blood test, and/or imaging exam.
Transmission of Disease
Consumption of food or water contaminated with feces from a
person or animal with tapeworm or ingestion of larvae cysts in meat
or muscle tissue of an animal with a tapeworm infection.
Treatment of Disease
Administration of oral medications that are toxic to the adult
tapeworm (including praziquantel, albendazole, and nitazoxanide).
Creutzfeldt-Jakob Disease (CJD)
Name of Infectious Agent
CJD Prion
Type of Infectious Agent
Prion
Symptoms of Disease
CJD is marked by rapid mental deterioration, usually within a few
months. Initial signs and symptoms typically include personality
changes, anxiety, depression, memory loss, impaired thinking,
blurred vision, insomnia, difficulty speaking, difficulty swallowing,
and sudden jerky movements. As the disease progresses, mental
symptoms worsen and people eventually lapse into a coma.
Diagnosis of Disease
Doctors commonly use an EEG, MRI, spinal fluid tests, and/or tonsil
biopsies to diagnose the disease.
Transmission of Disease
CJD disease is caused by an abnormal version of a kind of protein
called a prion. Normally the proteins are harmless, but when they’re
misshapen they become infectious and can cause major problems
on normal biological processes. Most people with CJD develop the
disease for no apparent reason, but others who develop the disease
have a family history of the disease or test positive for a genetic
mutation associated with CJF. A small number of people have
developed CJD after being exposed to infected human tissue during
a medical procedure. This happens because standard sterilization
methods do not destroy abnormal prions.
Treatment of Disease
No effective treatment exists for Creutzfeldt-Jakob disease or any of
its variants.
Cryptosporidiosis
Name of Infectious Agent
Cryptosporidium parvum parasite
Type of Infectious Agent
Protozoa
Symptoms of Disease
A gastrointestinal disease whose symptoms include watery
diarrhea, dehydration, weight loss, stomach cramps or pain, fever,
nausea, and vomiting.
Diagnosis of Disease
The infection can be diagnosed with an acid-staining test which
identifies cryptosporidium under the microscope or a stool culture.
Transmission of Disease
The infection begins when you ingest the parasite which then travels
to your intestinal tract and settles into the walls of your intestines.
You can become infected with cryptosporidium by touching anything
that has come in contact with contaminated feces. Methods of
infection include swallowing or putting something contaminated in
your mouth, drinking contaminated water, swimming in
contaminated water and accidentally swallowing some of it, touching
your hand to your mouth if you had comes into contact with a
contaminated surface, or having close contact with other infected
people or animals.
Treatment of Disease
Administration of anti-parasitic drug, anti-motility agents to slow
down the movements of the intestines, and fluid replacement
therapy.
Athlete’s Foot (Tinea pedis)
Name of Infectious Agent
Dermatophytes
Type of Infectious Agent
Fungus
Symptoms of Disease
Symptoms include itching, stinging, and burning between the toes;
itching, stinging, and burning on the soles of the feet; itchy blisters;
cracking and peeling skin, especially between the toes and on the
soles of the feet; excessive dryness of the skin on the bottoms or
sides of the feet; and/or toenails that are thick, crumbly, ragged,
discolored, or pulling away from the nail bed.
Diagnosis of Disease
Skin scrapings or samples from the infected area are taken and
viewed under a microscope.
Transmission of Disease
Athlete's foot thrives in thick, tight shoes that squeeze the toes
together and create warm, moist areas between them. Damp socks
and shoes and warm, humid conditions also favor the organisms'
growth. The fungus is transmitted by sharing clothes or shoes with
someone who has the fungal infection or walking barefoot in public
areas where the infection can spread.
Treatment of Disease
Administration of antifungal medication.