Disease Spread

Vector an insect or other organism that transmits a pathogenic fungus, virus, bacterium, etc. 2. any agent that acts as a carrier or transporter, as a virus or plasmid that conveys a genetically engineered DNA segment into a host cell

Disease Out break 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 as an epidemic or pandemic.

Out break A disease outbreak is the occurrence of cases of disease in excess of what would normally be expected in a defined community, geographical area or season. An outbreak may occur in a restricted geographical area, or may extend over several countries. It may last for a few days or weeks, or for several years. A single case of a communicable disease long absent from a population, or caused by an agent (e.g. bacterium or virus) not previously recognized in that community or area, or the emergence of a previously unknown disease, may also constitute an outbreak and should be reported and investigated

Epidemic An epidemic is the rapid spread of infectious disease to a large number of people in a given population within a short period of time, usually two weeks or less

Epidemic An illness or health-related issue that is showing up in more cases than would normally be expected. It occurs when an infectious disease spread rapidly to many people.

SARS? Severe acute respiratory syndrome (SARS) is a viral respiratory illness caused by a coronavirus, called SARS-associated coronavirus (SARS-CoV). SARS was first reported in Asia in February 2003. Over the next few months, the illness spread to more than two dozen countries in North America, South America, Europe, and Asia before the SARS global outbreak of 2003 was contained. The SARS outbreak of 2003 According to the World Health Organization (WHO), a total of 8,098 people worldwide became sick with SARS during the 2003 outbreak. Of these, 774 died. In the United States, only eight people had laboratory evidence of SARS-CoV infection. All of these people had traveled to other parts of the world with SARS. SARS did not spread more widely in the community in the United States. See an update on SARS cases in the United States and worldwide as of December 2003. SARS – 2003 Epidemic

Has to meet three conditions: What is a pandemic? Pandemic – spread of infectious diseases through large regions of populations; generally from continent to continent Has to meet three conditions: Emergence of a disease new to a population Agents infect humans, causing serious illness Agents spread easily and be sustainable among humans

Pandemic Pandemic normally is used to indicate a far higher number of people affected than an epidemic. Pandemic also refers to a much larger region being affected. In the most extreme case, the entire global population would be affected by a pandemic.

Epidemic / Pandemic / 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. If you observe what you think might be a disease outbreak, report it right away to your health care provider or public health department. 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 A pandemic is a global disease outbreak. HIV/AIDS is an example of one of the most destructive global pandemics in history. Influenza pandemics have occurred more than once. Spanish influenza killed 40-50 million people in 1918. Asian influenza killed 2 million people in 1957. Hong Kong influenza killed 1 million people in 1968.

What is the difference between a pandemic and an epidemic? Pandemics are epidemics at a much larger scale; they affect much more people at a larger geographical scale An epidemic must be a disease or condition that is NOT infectious, such as cancer. Pandemics MUST be infectious or contagious. Pandemic is typically wide spread area 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. Whereas 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.

Bubonic Plague Smallpox Cholera Malaria Influenza Yellow Fever Historical Pandemics Bubonic Plague Smallpox Cholera Malaria Influenza Yellow Fever

Bubonic Plague A zoonotic disease (can be transferred from animals to humans) Transmitted between animals and humans thru flea bites Incubation Period: 7-10 days after infection Symptoms: Bacteria enters from the bite and goes to the nearest lymph node, which then swells up and may become an open sore Treatment: antibiotics and supportive therapy.

Cholera Cholera is an acute intestinal infection caused by ingesting food or water that is contaminated Incubation period: 1 – 5 days Symptoms: Extreme watery diarrhea that can lead to severe dehydration and death, vomiting also occurs Treatment: oral rehydration salts to replace lost fluids usually results in cure; in severe cases, intravenous administration of fluids may be required

Yellow Fever A zoonotic disease transmitted by mosquitoes between humans and monkeys Incubation Period: 3-6 days after infection Symptoms: “Acute Phase” – fever, muscle pain, headache, shivers, vomiting “Toxic Phase” – fever reappears, jaundice, bleeding, bloody vomit If a patient enters the “toxic phase” there is only a 50% chance they will survive. Treatment: No specific treatments, though vaccination is highly recommended as a preventive measure

Smallpox Smallpox is a contagious disease caused by a virus and is said to have originated over 3,000 years ago in India or Egypt Incubation Period: 7-17 days after exposure Symptoms: Fever, vomiting, severe muscle aches, smallpox rash, blindness Treatment: No treatments were ever developed, however a vaccine was created and successfully eradicated the disease in 1980

Malaria is a zoonotic disease caused by a parasite and is transmitted by the bites of infected mosquitoes Incubation Period: 10-15 days after bite Symptoms: fever, headache, vomiting If not treated, it can quickly become life-threatening by disrupting the blood supply to organs Treatment: Antimalarial medicine within 24 hours of the onset of symptoms, supportive therapy Malaria

Introduction to Influenza Influenza is a viral infection that affects mainly the nose, throat, bronchi, and lungs Generally lasts for a week, but in the very young, elderly, and those with serious medical conditions, it can lead to severe complications and death

Background on Influenza Pandemics Influenza pandemics are rare, but have a high fatality rate. Three flu pandemics have occurred in the past century: The Spanish flu of 1918, Asian flu of 1957, and the 1968 Hong Kong flu. Death toll from the Spanish flu of 1918 was estimated to be 20-50 million worldwide. Over half a million people died in the U.S. from the Spanish Flu. More people died from the Spanish flu than were killed in World War I. The current population of Georgia is around 8 million.

Spanish Flu 1918

H5N1 Avian Influenza (Bird Flu) Important Points to Remember: There is no bird flu present in the U.S. today. The U.S. does NOT import poultry products from other countries. There is no danger of getting bird flu from eating chicken. You cannot get bird flu from properly cooked chicken. Cooking would kill any virus. Keep all poultry products properly refrigerated and cook thoroughly before eating.

Introduction to Bird Flu Bird flu is a lethal variant of the flu virus that poses a major threat to the world’s population. The deadly flu pandemic of 1918 (the Spanish flu) was a strain related to bird flu. Bird flu has reappeared in the past decade, and there is growing concern that another pandemic will occur in the near future. Introduction to Bird Flu

Education about bird flu will be important in an outbreak to help prevent infection and control panic. Scientists have stated that we are “overdue” for another flu pandemic.

What causes avian influenza? Wild birds such as ducks and geese have been shown to be “silent carriers” of the virus. Wild birds can spread the virus to domestic poultry flocks. Bird flu is especially devastating to domestic poultry. In the 1997 Hong Kong outbreak, every chicken was killed to prevent the spread to humans.

What causes avian influenza? Two forms of the virus can be found in birds. One form is mild while the other is extremely contagious and rapidly fatal. A strain known as the H5N1 virus has caused widespread domestic poultry outbreaks since 2003. The H5N1 is a zoonotic strain. It has the unique ability to cross the species barrier from birds to humans. What causes avian influenza?

H5N1 Pandemic Potential Research shows that the H5N1 virus could have pandemic potential. The virus that infects birds has mutated into a strain that is contagious to humans. If the virus adapts into a contagious strain capable of infecting humans, the H5N1 virus will no longer be a “bird flu.” It will be a “human flu.”

H1N1 Swine Influenza A (Swine Flu) Important Points to Remember: There is no danger of getting swine flu from eating pork. Properly cooking any meat would kill viruses. There is no danger in touching pigs, though you should avoid sneezing, sick- looking animals. Generally, the H1N1 virus is spread by human-to-human contact, not swine-to- human contact

Introduction to Swine Flu Swine flu is also a lethal variant of the flu virus that may potentially pose a major threat to the world’s population The technical term for the most recent 2009 outbreak is the H1N1 virus Introduction to Swine Flu

There have only been four major variations of the flu found in swine: H1N1, H1N2, H3N2, and H3N1 The symptoms that appear tend to be very similar to a regular flu: fever, cough, sore throat, body aches, etc. The major difference, however, is that if left untreated, the H1N1 virus has a bigger probability of causing severe problems that might lead to death.

What causes swine influenza? The most recent outbreak of the H1N1 virus formed in Mexico. The form of flu that originated in Mexico is a genetic mixture of viruses that have been seen in pigs, birds and people. The reason why it’s being called a “swine flu” is because the overall structure of the virus is of the type that affects pigs. What causes swine influenza?

H1N1 Pandemic Potential Researchers believe that even though the H1N1 virus is deadly, it isn’t currently at a pandemic stage. It does, however, have the potential of becoming a pandemic if not quickly taken care of. There is danger in having a strain originating from swine because swine is similar to both humans and to other animals when it comes to its genetics. So catching a flu from another animal, such as a bird, and then spreading the virus to humans is possible.

Ways to prevent influenza Get a yearly flu vaccination – though this won’t prevent you from getting a new strain of the virus, it can help reduce the chance of you catching the virus. Basic flu prevention can include: staying away from people who seem to be sick with the flu, washing hands constantly, etc. Masks also can be worn to prevent inhaling germs, but may not prevent all germs from entering the body.

Prevention Prevention: Slowing the Spread of Pandemic Disease There is no foolproof method for preventing the spread of disease during an influenza outbreak, epidemic, or pandemic. Although a vaccine is not likely to be available at first, today it is easier to produce specific vaccines more quickly than in the past. Once a vaccine becomes available, certain individuals and groups will be vaccinated first. If mass vaccination clinics become available in your community, be prepared to provide medical information about your family. In addition to vaccinations, you can take other prevention steps like these. Wash your hands often with soap and water. If these are not available, use an alcohol-based hand cleaner or gel sanitizer. If using a gel, rub your hands until they become dry. Avoid touching your mouth, nose, or eyes with your hands unless you've just washed your hands. When you cough or sneeze, cover your mouth and nose with a tissue. Then throw the tissue in the trash. Wash your hands afterward. Avoid crowded places as much as you can and stay home if you show signs of illness. Depending on the severity of the pandemic, consider wearing a face mask if you must go into a crowded area or be within 6 feet of others. Consider wearing a face mask if you must come into close contact with an infected person.

Making Vaccines Virtual Lab http://www. pbs Making Vaccines Virtual Lab http://www.pbs.org/wgbh/nova/bioterror/vacc_flash.html What kills pathogens virtual lab Pandemic 3 Phttp://www.pbs.org/wgbh/nova/bioterror/vacc_flash.htmlandemic 3: see how fast you can spread the disease before you get caught Become fighters against the Macrophage: Phahttp://www.pbs.org/wgbh/nova/bioterror/vacc_flash.htmlge Wars: Become Macrophage Fighters