Abney’s 2013 Infectious Diseases:
1) Airborne and Direct Contact Diseases
Airborne Diseases
Airborne diseases are caused by pathogenic microbes small enough to be discharged from an infected person
via coughing, sneezing, laughing and close personal contact or aerosolization of the microbe. The discharged
microbes remain suspended in the air on dust particles, respiratory and water droplets. Illness is caused when
the microbe is inhaled or contacts mucus membranes or when secretions remaining on a surface are touched.
Contact Diseases
Contact Diseases are transmitted when an infected person has direct bodily contact with an uninfected person
and the microbe is passed from one to the other. Contact diseases can also be spread by indirect contact with an
infected person’s environment or personal items. The presence of wound drainage or other discharges from the
body suggest an increased potential for risk of transmission and environmental contamination. Precautions that
create a barrier and procedures that decrease or eliminate the microbe in the environment or on personal
belongings, form the basis of interrupting transmission of direct contact diseases.
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Anthrax - A serious disease caused by Bacillus anthracis, a bacterium that forms spores. A bacterium is
a very small organism made up of one cell. Many bacteria can cause disease. A spore is a cell that is
dormant (asleep) but may come to life with the right conditions.
Coronavirus - Coronaviruses are a large family of viruses that includes viruses that may cause a range of
illnesses in humans, from the common cold to SARS and MERS.
Group A Streptococcus - A bacterium often found in the throat and on the skin. People may carry group
A streptococci in the throat or on the skin and have no symptoms of illness. Most GAS infections are
relatively mild illnesses such as "strep throat," or impetigo. Occasionally these bacteria can cause severe
and even life-threatening diseases.
Invasive Group B Streptococcal (GBS) - A bacterium that causes illness in newborn babies, pregnant
women, the elderly, and adults with other illnesses, such as diabetes or liver disease. GBS is the most
common cause of life-threatening infections in newborns.
Haemophilus influenza - Invasive disease caused by Haemophilus influenzae type b can affect many
organ systems. The most common types of invasive disease are pneumonia, occult febrile bacteremia,
meningitis, epiglottitis, septic arthritis, cellulitis, otitis media, purulent pericarditis, and other less
common infections such as endocarditis, and osteomyelitis.
Legionellosis - An infection caused by the bacterium Legionella pneumophila. Maine monitors the
incidence of Legionellosis through mandatory reporting by health care providers, clinical laboratories
and other public health partners.
Meningococcal Disease - The leading cause of bacterial meningitis in children and young adults in the
United States. Symptoms of meningococcal disease include fever, headache and stiff neck in meningitis
cases, and sepsis and rash in meningococcemia.
MERS-CoV - Currently, all cases are associated with either direct travel to the Arabian peninsula, or
contact with a returned traveler from the Arabian peninsula.
MRSA - Methicillin-resistant Staphylococcus Aureus is a bacterial infection that is resistant to some
antibiotics. When MRSA bacteria are found on the skin but do not cause illness it is called
"colonization." In most cases, MRSA does not cause any problems or causes minor infections, such as
pimples or boils. In some cases, MRSA can cause more serious infections.
Plague - Plague is a disease caused by Yersinia pestis (Y. pestis), a bacterium found in rodents and their
fleas in many areas around the world.
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Strep pneumoniae - a Gram-positive encapsulated coccus that often colonizes the human nasopharynx,
where it can be carried asymptomatically.
SARS - respiratory disease caused by a coronavirus, last reported in 2004
Source: http://www.maine.gov/dhhs/mecdc/infectious-disease/epi/airborne/
Other Airborne:
Many common infections can spread by airborne transmission at least in some cases, including: Anthrax
(inhalational), Chickenpox, Influenza, Measles, Smallpox and Tuberculosis.
Source: Wikipedia
2) Food-borne and Diarrheal Diseases
Food-borne illness is caused by consuming food or beverages that are contaminated by certain bacteria, viruses
or parasites. Some disease may be caused by toxins or poisonous chemicals if they are present in the food.
Individuals may also be exposed to these same pathogens through recreational water sports, contact with
animals and their environment, and person-to-person spread.
Food-borne and Diarrheal Diseases
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Botulism - Botulism is a serious, potentially fatal illness caused by a type of poison. The poison –
known as botulinum toxin – is produced by a kind of bacteria. Botulinum toxin is the strongest poison
known to science.
Campylobacteriosis– Campylobacter, often called campy, are bacteria that can cause diarrheal disease in
humans. The bacteria are common in chickens, but don’t make the chicken sick.
Cryptosporidiosis - This illness is most frequently associated with contaminated water. The disease is
caused by parasites that can live in the intestines of animals and infected humans.
Escherichia coli -There are hundreds of different strains of E. coli and most strains do not make people
sick. The most serious strains are called shiga toxin producing e-coli (STEC) that can cause bloody
diarrhea.
Giardiasis – Giardiasis is sometimes known as “beaver fever” because beavers (as well as dogs, cats,
horses and cows) are a major reservoir for the parasite that causes infection.
Hepatitis A – The hepatitis A virus (HAV) can cause liver disease. The virus spreads more easily where
there is poor sanitary conditions and personal hygiene. A vaccine is available to prevent getting this
disease.
Listeriosis - Listeriosis, a serious infection caused by eating food contaminated with the bacterium
Listeria monocytogenes, has recently been recognized as an important public health problem in the
United States.
Norovirus – This group of viruses cause “stomach flu” or gastroenteritis in people. Individuals may
become very sick with acute vomiting and diarrhea but usually the symptoms last only 1-2 days. These
viruses are the most common cause of food-borne outbreaks.
Salmonella - Most persons with salmonellosis get diarrhea, fever, and stomach cramps 12 to 72 hours
after infection. The illness usually lasts 4 to 7 days, and most persons recover without treatment.
Shigellosis - There are many different types of Shigella. One type, Shigella sonnei, causes over twothirds of the shigellosis in the United States. A second type, Shigella flexneri, accounts for almost all of
the rest. Other types of Shigella are rare in this country, but are important causes of disease in the
developing world.
Source: http://www.maine.gov/dhhs/mecdc/infectious-disease/epi/food-borne.shtml
3) Vector-borne Diseases:
Tick Borne Diseases:
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Anaplasmosis
Babesiosis
Ehrlichiosis
Lyme
Powassan Encephalitis
Mosquito-Borne Diseases:
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Dengue
Eastern Equine Encephalitis
Malaria
West Nile Virus
Mosquito Resources:
Tick Resources:
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Tick-borne Diseases in Maine: A Physician’s
Reference Guide
Lyme Disease Awareness Month Activities
o Tick ID Game
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Maine Arboviral (Mosquito-borne) Illness
Surveillance, Prevention and Response
Plan, 2013 Season (word*)
Municipality Information on Mosquitoes
Mosquito Youth Education
Source: http://www.maine.gov/dhhs/mecdc/infectious-disease/epi/vector-borne/index.shtml
4) Recreational Water Illness (RWI)
What are RWIs?
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Recreational water illnesses (RWIs) are caused by germs spread by swallowing, breathing in mists or
aerosols of, or having contact with contaminated water in swimming pools, hot tubs, water parks, water
play areas, interactive fountains, lakes, rivers, or oceans. RWIs can be a wide variety of infections,
including stomach, skin, ear, respiratory, eye, neurologic and wound infections. The most commonly
reported RWI is diarrhea.
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Swallowing water that has been contaminated with germs is the primary way RWIs are spread. Water
can be contaminated from stool, sewage spills, animal waste and water runoff during rainfall. Some
RWIs are caused by germs that live naturally in the environment. Proper disinfectant levels in pools or
hot tubs will kill most germs.
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Chlorine does kill germs that cause RWIs but the time that it takes to kill each germ varies. Some germs,
like Cryptosporidium (frequently referred to as Crypto) can survive for days in a properly disinfected
pool. This makes it very important to keep the germs out of the water.
5) Hepatitis
Hepatitis means inflammation of the liver. Toxins, certain drugs, some diseases, heavy alcohol use, and
bacterial and viral infections can all cause hepatitis. Hepatitis is also the name of a family of viral infections that
affect the liver; the most common types in the United States are hepatitis A, hepatitis B, and hepatitis C.
These unrelated viruses are spread from one person to another through different routes. Safe and effective
vaccines have been available for hepatitis B since 1981 and for hepatitis A since1995. No vaccine exists yet
against hepatitis C. All three of these viruses can produce an illness characterized by nausea, abdominal pain,
and jaundice. HBV and HCV also can produce a chronic infection that is associated with an increased risk for
chronic liver disease and liver cancer.
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Hepatitis A is a contagious liver disease that results from infection with the hepatitis A virus. It can
range in severity from a mild illness lasting a few weeks to a severe illness lasting several months.
Hepatitis B is a contagious liver disease that results from infection with the hepatitis B virus (HBV). It
can range in severity from a mild illness lasting a few weeks to lifelong infection, cirrhosis (scarring) of
the liver, liver cancer, liver failure, and death.
Hepatitis C is a contagious liver disease that results from infection with the hepatitis C virus. It can
range in severity from a mild illness lasting a few weeks to a serious, lifelong illness.
6) Zoonotic Diseases
Zoonotic diseases/infections are those which can be naturally transmissible from vertebrate animals to humans.
Approximately 75% of recently emerging infectious diseases affecting humans are diseases of animal origin.
Many factors like Environmental changes, human and animal demography, pathogen changes and changes in
farming practice lead to the emergence of zoonotic diseases. Social and cultural factors such as food habits and
religious beliefs play a role in the emergence of zoonotic diseases.
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Rabies - Rabies is a viral disease of the central nervous system (brain and spinal cord) that is most often
transmitted through the bite or scratch of a rabid animal. The vast majority of rabies cases occur in wild
animals like raccoons, skunks, bats, and foxes. Domestic animals account for less than 10% of the
reported rabies cases, with cats, cattle, and dogs most often reported rabid.Rabies in humans is very rare
in the U.S., but is almost always fatal.
Brucellosis - Brucellosis is an infectious disease caused by the bacteria of the genus Brucella. These
bacteria can cause disease in many different animals. Humans become infected by coming in contact
with animals or animal products that are contaminated with these bacteria.
Q fever - Q fever is a zoonotic disease caused by Coxiella burnetii, a species of bacteria that is
distributed globally. Q fever mainly affects cattle, sheep and goats and can be passed to humans
primarily by inhalation of these organisms from air that contains airborne barnyard dust contaminated by
dried placental material, birth fluids, and excreta of infected herd animals.
Hantavirus (Hantavirus Pulmonary Syndrome) - Hantavirus pulmonary syndrome (HPS) is a deadly
disease from rodents. Humans can contract the disease when they come into contact with infected
rodents or their urine and droppings.
Leptospirosis - Leptospirosis is a bacterial disease that affects humans and animals. In humans it causes
a wide range of symptoms, and is confirmed by laboratory testing of a blood or urine sample.
Psittacosis – also known as parrot fever and ornithosis — is a bacterial infection of humans that can
cause severe pneumonia and other serious health problems. Many different bird species can be infected
with Chlamydia psittaci and spread the disease.
Trichinosis - Trichinosis, also called Trichinellosis, is caused by eating raw or undercooked meat of
animals infected with the larvae of a species of worm called Trichinella. Infection occurs commonly in
certain wild carnivorous (meat-eating) animals but may also occur in domestic pigs.
Tularemia - Tularemia is a potentially serious illness that occurs naturally in the United States. It is
caused by the bacterium Francisella tularensis found in animals (especially rodents, rabbits, and hares).
Source: http://www.maine.gov/dhhs/mecdc/infectious-disease/epi/zoonotic/index.shtml
7) Pathogenic fungi
Pathogenic fungi are fungi that cause disease in humans or other organisms. The study of pathogenic fungi is
referred to as "medical mycology." Although fungi are eukaryotic organisms, many pathogenic fungi are also
microorganisms.[1]
Candida:
Candida species are important human pathogens that are best known for causing opportunist infections in
immunocompromised hosts (e.g. transplant patients, AIDS sufferers, cancer patients). Infections are difficult to treat and
can be very serious: 30-40% of systemic infections result in death.[citation needed] The sequencing of the genome of C.
albicans and those of several other medically relevant Candida species has provided a major impetus for Candida
comparative and functional genomic analyses. These studies are aiding the development of sensitive diagnostic
strategies and novel antifungal therapies.[2]
Aspergillus:
Aspergillosis.
Aerosolized Aspergillus spores are found nearly everywhere so we are routinely and almost constantly exposed to them.
Such exposure is a normal part of the human condition and generally poses no adverse health effects. Nevertheless,
Aspergillus can and does cause disease in three major ways: through the production of mycotoxins; through induction of
allergenic responses; and through localized or systemic infections. With the latter two categories, the immune status of
the host is pivotal. Allergies and asthma are thought to be caused by an active host immune response against the
presence of fungal spores or hyphae. In contrast, with invasive aspergillosis, the immune system has collapsed and little
or no defence can be mounted.[3]
The most common pathogenic species are Aspergillus fumigatus and Aspergillus flavus. Aspergillus flavus produces
aflatoxin which is both a toxin and a carcinogen and which can potentially contaminate foods such as nuts. Aspergillus
fumigatus and Aspergillus clavatus can cause allergic disease. Some Aspergillus species cause disease on grain crops,
especially maize, and synthesize mycotoxins including aflatoxin. Aspergillosis is the group of diseases caused by
Aspergillus. The symptoms include fever, cough, chest pain or breathlessness. Usually, only patients with weakened
immune systems or with other lung conditions are susceptible.[1][3]:)
Cryptococcus:
Cryptococcus neoformans can cause a severe form of meningitis and meningo-encephalitis in patients with HIV infection
and AIDS. The majority of Cryptococcus species live in the soil and do not cause disease in humans. Cryptococcus
neoformans is the major human and animal pathogen. Cryptococcus laurentii and Cryptococcus albidus have been
known to occasionally cause moderate-to-severe disease in human patients with compromised immunity. Cryptococcus
gattii is endemic to tropical parts of the continent of Africa and Australia and can cause disease in nonimmunocompromised people.[1]
Histoplasma:
Histoplasmosis.
Histoplasma capsulatum can cause histoplasmosis in humans, dogs and cats. The fungus is most prevalent in the
Americas, India and southeastern Asia. It is endemic in certain areas of the United States. Infection is usually due to
inhaling contaminated air.
Pneumocystis:
Pneumocystis jirovecii (or Pneumocystis carinii) can cause a form of pneumonia in people with weakened immune
systems, such as premature children, the elderly, and AIDS patients.[4]
Stachybotrys:
Stachybotrys chartarum or "black mold" can cause respiratory damage and severe headaches. It frequently occurs in
houses in regions that are chronically damp.
Source: wikipedia