Disease What is the difference between and infectious

Disease What is the difference between and infectious disease and noninfectious disease? How are disease transmitted ?

Noninfectious Disease Infectious Disease

Disease �Any condition that abnormally effects the function of an organism. �Causes include pathogens (germs), environmental, and genetics.

Noninfectious Diseases � Non-infectious diseases (also called Non- communicable diseases ) are those diseases that are not caused by a pathogen and cannot be shared from one person to another. � Non-infectious diseases may be caused by either � the environment- : chemical exposure, carcinogens, air pollution, water pollution, food safety ● nutritional deficiencies 1. Overnutrition- is frequent overconsumption of food. Leads to obesity. 2. Malnutrition- when your body does not get enough nutrients. �lifestyle choices- diet, exercise, tobacco, alcohol, drugs, and stress �genetic inheritances- inheritance plays a part in determining lifespan and the likelihood of developing certain illnesses.

Infectious Disease �Infectious diseases are caused by pathogens. �A pathogen is a microorganism that causes a disease such as a virus, bacteria, protist or fungi. �Pathogens are transmitted through direct contact and indirect contact with an infected person, an infected animal, a contaminated object or food, water and soil. � A vector is an organism that passes a disease to humans.

How are Pathogens Spread? • The 4 Ways Pathogens Spread: – Infected People – Infected Animals – Contaminated Object – Soil, Food, and Water

Infected People • Pathogens pass from one person to another person… • Directly - Kissing, Shaking Hands, etc. and • Indirectly - Sneezing, Coughing, etc.

Infected Animals • Infected animals can bite a person and pass the pathogen to them. • Example: Ticks can transmit Bacteria to humans when they bite, giving the humans Lyme Disease.

Vectors • Vectors - The hosts or carriers that spread pathogens and disease. • Examples: Mosquitos, Ticks, Dogs

Vector-borne Diseases • Vector-borne Disease – Any diseases that is spread to humans through direct contact with an infected animal. • Examples: Rabies from a dog bite, Lyme disease from a Tick, Malaria from a Mosquito

Contaminated Object • Pathogens that can survive outside the body are transferred from infected person, to an object, and then to another person.

Soil, Food, and Water • Some pathogens occur naturally in the environment and can be transferred to people through soil, food and water. • Examples: Cholera and Dysentary are two deadly diseases that spread through food and water.

The Germ Theory �States that specific germs/ pathogens cause specific diseases.

Protists � Entamoeba histolytica � Causes dysentery, a severe form of amebiasis associated with stomach pain, bloody stools, and fever. • Plasmodium, a one-celled parasite transmitted by a mosquito. • Causes malaria, which causes flu-like symptoms and intestinal problems. Plasmodium attacking a red blood cell

Bacteria � Streptococcus Bacterium � Causes strep throat, a painful sore throat and fever. l Mycobacterium tuberculosis l Causes tuberculosis, a highly contagious respiratory disease.

Viruses l l Retroviridae - HIV (Human Immunodeficiency Virus) Causes Acquired Immunodeficiency Syndrome (AIDS), which is a deadly disease that attacks the human immune system. � Orthomyxoviridae – Influenza virus � Causes the flu, which is a respiratory infection that often causes the infected person to have a fever, headache, and body aches.

What is an Infectious Disease? • Infectious Disease - A disease that is caused by pathogens entering your body. • Pathogen - Any organism that causes a disease.

Pathogens • Major Human Pathogens: –Parasites –Bacteria –Viruses –Fungi –Protozoans

Non-Infectious Diseases and your Health

Noninfectious Diseases ● Diseases that are not caused by pathogens and not transmitted from person to person. *Also known as Non-communicable diseases ● Over history, infectious diseases have decreased, noninfectious have increased. ● Examples: diabetes, heart disease, cancer

Causes of Noninfectious Diseases ● Lifestyle Choices: diet, exercise, tobacco, alcohol, drugs, and stress ● Environmental Factors: chemical exposure, carcinogens, air pollution, water pollution, food safety ● Genetics: inheritance plays a part in determining lifespan and the likelihood of developing certain illnesses.

Diseases related to Diet and Exercise ● Diseases: ● Causes: ● Hypertension ● High ● Heart Disease ● High ● Type II Diabetes salt in diet Saturated Fat and Cholesterol ● Sugary Diet, Excess weight, Inactivity

Tobacco (lifestyle choice) Tobacco products contain carcinogens and the addictive substance nicotine. Tobacco use and/or secondhand exposure increases risk of cancer, heart disease, asthma, and emphysema.

Alcohol (lifestyle choice) Overuse of alcohol can lead to cirrhosis, pancreatitis, and heart disease. ● Pregnant women who drink may cause their baby to be born with fetal alcohol syndrome. FAS babies may have mental disabilities, physical deformities, and other birth defects. ●

Environmental Factors ● Radon gas: lung cancer ● Air pollution: asthma and cancer ● Water pollution: cancer and birth defects ● UV radiation: skin cancer

What is Cancer? Cancer- abnormal cells divide out of control (uncontrolled mitosis) Carcinogens – Chemicals that cause cancer

Genetics ● Genetics play a factor in a person’s susceptibility to certain diseases. This explains why some people can smoke their whole lives and do not get cancer and some people smoke for a year and get cancer. Example: Cystic Fibrosis is caused by a Genetic Mutation in a person’s DNA

Virus, Bacteria, Fungus and Protists Essential Questions 1. Identify unique characteristics for each type of microbes. 2. Compare and Contrast these three groups of microbes.

Viruses �Viruses are a tiny, nonliving particle that enters and then reproduces inside a living cell. �A virus is composed of genetic material (DNA or RNA) inside a protein coat.

Viruses �Viruses are specific to certain host cells. �A bacteriaphage is a virus that infects bacteria.

Viruses �A virus must infect a host cell in order to use the cells materials to reproduce more viruses. �Viruses can cause disease.

Viruses �Active vs. Hidden viruses �Active viruses multiply immediately after injecting its genetic material into the host cell. Example - Influenza virus �Hidden viruses can wait to multiply even after injecting its genetic material into the host. Example. Cold Sore

Viruses �Diseases caused by viruses include: � Influenza, polio, chicken pox, Ebola, and AIDS � �Treatments: antiviral medications �

Bacteria � Bacteria are single celled organisms but can form chains or clumps of independent cells. � Shapes include rod, sphere, and spiral. � They are prokaryotes, the genetic material is not found in a nucleus, but floats freely in the cytoplasm. � Bacteria do NOT contain organelles other than ribosome’s.

Bacteria � Bacteria can reproduce through sexual and asexual reproduction. �Asexual- called Binary fission- A cell first duplicates its genetic material and then divides into two identical cells. �Sexual- called Conjugation. Bacterium transfers some of its genetic material into another bacterium through a thin, threadlike bridge that joins the two cells.

Bacteria �Bacteria may have simple, single stranded flagella that rotates and allows the bacteria to move. �Bacteria can cause disease but are also useful in oxygen and food production, environmental recycling and medicine production. �Antibiotics are chemicals that kill

Bacteria �Examples: : Rabies, Lyme Disease and Leprosy. �Treatments: antibiotics such as Penicillin, amoxicillin, or others

Protists � Most protists are single celled organisms, but some are multi cellular. � Protists are eukaryotes; they have a distinct nucleus containing genetic material. � Protists have a variety of other organelles including vacuoles, mitochondria, chloroplasts, etc. ) � Protists may contain flagella or cilia that allow the cell to move. Some contain pseudopods which are temporary bulges of the cell used for movement and trap food.

Protists �Many Protists are carried by a vector, a carrier of a disease that passes it on to a human host ie. mosquito, tick. �Diseases caused by Protists include: Malaria (Plasmodia) � Amoebic Dysentery (Entamoeba histolytica) � Giardiasis

Protists �There are 3 types of protists: �Plantlike forms (Euglena) that get energy through photosynthesis are autotrophes.

Protists • Animal-like forms (Amoeba and Paramecium) that move through their environment and eat other organisms or decaying parts of other organisms are heterotrophes.

Protists • Fungus-like (Slime mold) that absorb nutrients from their environment are heterotrophes.

Fungus �Most fungi are eukaryotes, they have a distinct nucleus. �They obtain energy from their environment, meaning they are heterotrophes. �They live in wet, moist environments.

Fungus � Reproduction: They reproduce through both sexual and asexual reproduction. �Asexual reproduction- similar to mitosis and binary fission certain fungi go through budding or create spores. �Sexual reproductionfungi will exchange DNA and produce spores with the new DNA.

Fungus �Examples of Fungal infections are ringworm, and Athlete’s foot (Tinea). �Treatments include antifungal medications.

Disease Prevention Your Body’s disease fighting mechanisms and vaccines, immunity � Let’s Review � How are infectious diseases spread? � Contaminated people � Contaminated objects � Animals � Soil, water and food

Disease Prevention Your Body’s disease fighting mechanisms and vaccines, immunity � Your body’s Resistance � The human body resists disease in a variety of ways � Barriers (First Line of Defense) � Your Skin � oils and sweat on the skin help kill pathogens � Pathogen may fall off or be washed off � Pathogen also has to get through a layer of dead skin cells on the surface of the skin � Breathing Passage (Respiratory System) � Nose pharynx, trachea and bronchi contain mucus and cilia � Together the mucus and cilia will trap and remove most pathogens

Disease Prevention Your Body’s disease fighting mechanisms and vaccines, immunity � Mouth and Stomach � Saliva in your mouth contains destructive chemicals that help destroy pathogens � Stomach-produces acids that can destroy pathogens � The Inflammatory Response (Second line of defense) � When cells in your body get damaged-your body triggers an inflammatory response � White blood cells begin to fight the pathogens � This is the second line of defense and is sometimes referred to as the body’s general defense response

Disease Prevention Your Body’s disease fighting mechanisms and vaccines, immunity � White Blood Cells (The Disease Fighters) � The type of white blood cell involved in destroying pathogens are called phagocytes � These cells surround and engulf pathogens � Inflammation � During the inflammation process blood vessels widen in the area of the affected area. This allows more blood flow to the impacted area.

Disease Prevention Your Body’s disease fighting mechanisms and vaccines, immunity � More blood flow means more white blood cells can get to the effected area � Fever � Sometimes in the inflammatory process a fever occurs. You may feel bad from a fever this actually helps your body fight the infection. �

Disease Prevention Your Body’s disease fighting mechanisms and vaccines, immunity � The Immune System (Third Line of Defense) � This is a directed attach on specific pathogens � The white blood cells that can distinguish between different pathogens are called lymphocytes � Two types T cells and B cells � T cells-identify and distinguish between pathogens � Each different T cell recognize a different pathogen by identifying that pathogens unique antigen. � Antigens are markers that are specific to each pathogen and have different chemical structures � Think of antigens as different athletic uniforms

Disease Prevention Your Body’s disease fighting mechanisms and vaccines, and immunity � B cells produce proteins that help destroy pathogens � These proteins are called antibodies � Antibodies are specific to a specific pathogen � The antibody and the antigen fit together like puzzle pieces

Disease Prevention Your Body’s disease fighting mechanisms and vaccines, immunity � Preventing Infectious Diseases � Immunity-the body’s ability to destroy pathogens before they can cause disease. � Active Immunity � The first time your body is attached by a pathogen your body makes antibodies to that pathogen. All proceeding times your body is attached by that pathogen, the antibodies made the first time are still present and will destroy the pathogen this second time.

Disease Prevention Your Body’s disease fighting mechanisms and vaccines, immunity � A person acquires active immunity when their own immune system produces antibodies to fight the pathogen. � T cells and B cells keep their “memory” of the first time they fought that pathogen � Active immunity can last for several years and sometimes for life � Vaccination � The second way to acquire active immunity � Vaccination is a way harmless way that antigens are introduced to the body

Disease Prevention Your Body’s disease fighting mechanisms and vaccines, immunity � The vaccine is the part of the vaccination process that contains the weakened pathogen containing the antigen which triggers the active immune response to produce antibodies to the pathogen � Antibiotics (Used for bacterial infections only) � Antibiotics are given to fight bacterial infections Structure of the basic penicillin backbone

Disease Prevention Your Body’s disease fighting mechanisms and vaccines, immunity � Passive Immunity � This occurs when antibodies are given to a person—the body does not make them. � Passive immunity typically does not last much longer than a few months � Example-rabies vaccines

Notes: Spread, Treatment, and Prevention of Disease

What is a disease outbreak? • A disease outbreak happens when a disease occurs in greater numbers than expected in a community or region, or during a season. • An outbreak may occur in one community or even extend to several countries. It can last from days to years. Sometimes a single case of a contagious disease is considered an outbreak. This may be true if it is an unknown disease, is new to a community, or has been absent from a population for a long time. An outbreak can be considered an epidemic or pandemic.

How do diseases spread? • Infectious diseases spread in many ways. – Pathogens can be found in many places including food, air, water, surfaces. – Contact with insects and other animals • Insects and animals can also carry organisms that cause disease. – Ex. Lyme Disease is caused by bacteria that inhabit ticks. – Rabies, a deadly central nervous system infection is caused by a virus and is found in the saliva of infected animals, such as bats, raccoons, etc.

– Person-to-Person Contact • Most of the illnesses you have had have probably been passed to you by another person. • To avoid giving/receiving pathogens, you should wash your hands.

What are Carriers and Vectors? • Carriers and vectors can spread disease, but generally do not get sick themselves. • Carrier: a person or animal that has a disease and can pass it on, but does not show any symptoms. • Vector: an organism (like a mosquito or tick) that carry pathogens from one organism to another.

How do we treat and prevent diseases? • Diseases caused by bacteria can be treated with medicines that contain antibiotics. – The first antibiotics were discovered in 1928 by a scientist named Flemming. • Antimicrobial: something that kills germs (includes hand sanitizer, antibiotics, etc. )

How do we treat and prevent diseases? (cont. ) • Scientists continue efforts to prevent and treat illness. – Vaccine: a substance that contains a weakened or killed pathogen, such as a bacterium or virus, that stimulates antibody production or cellular immunity against the pathogen but cannot cause severe infection. Vaccines prevent illnesses (not treat them!). The use of vaccines has made some diseases nearly extinct. Brainpop

– Antibiotics fight pathogens (bacteria), but they can also lead to changes in them. • When an antibiotic is used too often, bacteria can develop resistance, meaning it is no longer affected by the antibiotic. Brainpop • The next time those bacteria invade your body, that particular antibiotic will not stop the disease.

What is the difference between an epidemic and a pandemic? • Epidemic and pandemic refer to the spread of infectious diseases among a population. – Epidemic: when a disease spreads to a large number of people, but remains in a specific, local area. – Pandemic: when a disease spreads to numerous places around the world. A widespread epidemic. In the most extreme case, the entire global population would be affected by a pandemic.

Epidemic vs. Pandemic (cont. ) • The terms epidemic and pandemic usually refer to the rate of infection, the area that is affected or both. – An epidemic is defined as an illness or healthrelated issue that is showing up in more cases than would normally be expected. It occurs when an infectious disease spreads rapidly to many people. In 2003, the severe acute respiratory syndrome (SARS) epidemic took the lives of nearly 800 people worldwide.

• An epidemic occurs when an infectious disease spreads rapidly to many people. • In 2003, the severe acute respiratory syndrome (SARS) epidemic took the lives of nearly 800 people worldwide. Epidemic vs. Pandemic

• Epidemic and pandemic are similar terms that refer to the spread of infectious diseases among a population. • There are two main differences between epidemic and pandemic: • A Pandemic effects a far higher number of people than an epidemic. • A Pandemic also refers to a much larger region being affected. In extreme cases, the entire global population would be affected by a pandemic. Epidemic vs. Pandemic

• In the case of a pandemic, even more of the population is affected than in an epidemic. A pandemic typically is in a widespread area (usually worldwide) rather than being confined to a particular location or region and affect global populations. An epidemic is not worldwide. For example, malaria can reach epidemic levels in regions of Africa but is not a threat globally.

Epidemic vs. Pandemic (cont. ) • However, a flu strain can begin locally (epidemic) but eventually spread globally (pandemic). This is not unusual for a new virus, because if people have not been exposed to the virus before, their immune systems are not ready to fight it off, and more people become ill. • Swine flu started in Mexico city, and it was feared to lead to epidemic proportions in North America. Now that the flu has been found in New Zealand, Israel, Scotland many other countries, it has become pandemic.

• The 1918 Spanish flu and the Black Plague are extreme examples of pandemics. Keep in mind, though, that a pandemic doesn't necessarily mean millions of deaths—it means a geographically widespread epidemic.

Influenza Pandemics • Influenza pandemics have occurred more than once. Spanish influenza killed 40 -50 million people in 1918. The Asian influenza killed 2 million people in 1957. The Hong Kong influenza killed 1 million people in 1968. • An influenza pandemic occurs when a new subtype of virus arises. This means humans have little or no immunity to it; therefore, everyone is at risk. The virus spreads easily from person to person, such as through sneezing or coughing.

• As it spreads, the virus can begin to cause serious illness worldwide. With past flu pandemics, the virus reached all parts of the globe within six to nine months. With the speed of air travel today, public health experts believe an influenza pandemic could spread much more quickly. A pandemic can occur in waves, and all parts of the world may not be affected at the same time. Brainpop

• The 1918 Spanish flu and the Black Plague are extreme examples of pandemics. • Keep in mind, though, that a pandemic doesn't necessarily mean millions of deaths - it means a geographically widespread epidemic. Extreme Pandemic

How can an Epidemic become a Pandemic? • When people travel to different continents they can spread infectious diseases. • Ways it can spread to other continents… • Travel by Airplane • Travel by Boat • Migrating Animals Epidemic vs. Pandemic

• Keep in mind, an epidemic is not worldwide. • For example, Malaria can reach epidemic levels in regions of Africa but is not a threat globally. Whereas a flu strain can begin locally (epidemic) but eventually spread globally (pandemic). Epidemic vs. Pandemic