AVIAN FLU
1. The common flu is not life threatening for much of the world’s population. If that is the case, then why does the avian influenza pose such high risks?
The avian influenza is more threatening than the common flu for several reasons. One is that the avian influenza originated in birds so when it crossed species lines, the virus went haywire since it’s not supposed to occur in other species. Another reason why the avian influenza is more threatening is because of the complications that could occur. When you contract the avian influenza, you could possibly develop pneumonia, respiratory failure, shock, altered mental state, seizures, failure of multiple organs (e.g. kidney failure), and you could die. On the other hand, with the seasonal influenza, or flu, possible complications include pneumonia, bronchitis, and ear infections. Not only are the complications of the common flu less severe, but most people overcome it in a few days to less than two weeks. The avian influenza, on the other hand, is much more severe and can be rapidly fatal. In addition, most people are vaccinated and or immune to the flu whereas people are not vaccinated and no one is immune against the avian flu. Therefore, the avian flu poses a higher risk.
2. How does an influenza virus infect the host cell?
Influenza infects the host cell by going through the cell wall and into the cytoplasm. There it dissolves and spreads its genetic code. Then the virus multiplies, destroys the host cell, and travels to other cells to repeat the process.
3. What kinds of changes must occur to allow avian influenza to be transmitted between individuals of different species, such as from birds to human?
An antigenic shift allows the avian influenza virus to be transmitted across species lines. Antigenic shift occurs since “influenza A viruses have eight separate gene segments. The segmented genome allows influenza A viruses from different species to mix and create a new virus if influenza A viruses from two different species infect the same person or animal.”
4. Can the existing avian influenza virus be transferred from one human host to another? Why or why not?
Yes. It is possible if a person is co-infected with the avian influenza A virus and the human influenza A virus. If this occurs, the genetic information of the two viruses could reassort “to create a new influenza A virus with a hemagglutinin gene from the avian virus and other genes from the human virus. Influenza A viruses with a hemagglutinin (against which humans have little or no immunity) that have reassorted with a human influenza virus are more likely to result in sustained human-to-human transmission and pose a major public health threat of pandemic influenza.”
5. In what regions of the world can avian influenza be found today? Who is most at risk of getting it?
Technically speaking everyone is at risk of getting avian influenza and it is found everywhere. However the newest strain of H7N9 has been found in China but there haven’t been any laboratory confirmed results of human infection.
6. The Spanish Flu epidemic of 1918 demonstrates why microbial evolution is a concern of scientists everywhere. What needs to happen for H5N1 to become a threat to public health?
For H5N1 to become a public health threat, it needs to demonstrate the ability to transmit quickly and effectively through humans, where each infected individual spreads it to many others. The strain also needs to be a more common occurrence in humans and in birds; If it is more common in birds it will be able to spread quickly over the poultry trade routes.
7. How do microbes evolve?
Microbes evolve by mutating and reproducing at a quick rate. When microbes develop a mutation that is resistant to certain drugs, natural selection will allow the microbes to reproduce the mutation more so it becomes common in the host organism. When scientists try to use antivirals on the host, the mutated microbes will spread and grow quicker.
8. Describe why the 1918 Spanish Flu pandemic was such a concern in terms of microbial evolution?
The Spanish Flu had evolved from an avian form of influenza, slowly mutating and spreading through people. As it spread into people, it had become very virulent due to the fact that it was in humans, although being a flu for birds.
9. How does microbial evolution lead to antibiotic and antiviral drug resistance?
They can either spontaneously evolve or become resistant due to a failing immune system allowing them to attack the host, such as HIV. With spontaneous mutations, THEY WILL BECOME PREDOMINANT UPON EXPOSURE TO THE ANTIVIRAL that they evolved resistant to.
10. How does our knowledge of microbial evolution permit a better understanding of the threats posed by avian influenza?
We would be able to detect when it obtains the ability to be easily transmissible between humans and be able to halt or curb its attempt to spread through the human population. We would also be able to detect whether or not a certain vaccine worked or not.
11. Each year a new seasonal flu vaccine is produced to fight the different strains of the virus that threaten to dominate in that particular period. What does this indicate about efforts to develop a vaccine for H5N1?
Each year a new seasonal flu vaccine is produced to fight the different strains of the virus that threaten to dominate that particular period. This indicates that our efforts to develop a vaccine for H5N1 are wasteful. The spending of vaccines yearly for a virus that will change to be resistant the next year is futile. Vaccine making techniques have become more efficient, but in the long run we need a different solution to the vaccination problem. Vaccines are not useless though since they help protect society from disease before they are afflicted.
12. What is a vaccine?
A vaccine is a small dosage of a disease to make your body produce antibodies against the virus.
13. How does a vaccine work with an individual’s immune system to protect an individual against disease?
Vaccines help provide immunity to disease by making the body produce antibodies to protect against the disease.
14. How are vaccines made?
Vaccines are made yearly from the virus that is trying to be defended against. The vaccine is produced from the virus and is injected into the patient in small doses to allow your body to produce antibodies against it.
15. What roles do vaccines play in ensuring the overall health of society?
Vaccines can protect the overall health of a society by increasing herd immunity in a society. Herd immunity is when a percent of a population is vaccinated they can act as buffers to the disease for the people who have not been infected yet.
16. Are there antivirals and vaccines for avian influenza? What needs to be done in order to develop some?
The current antivirals for the avian flu are Tamiflu and Relenza. They are drugs that target proteins in a cell to inhibit the spread of viruses. The antiviral are only effective if they are given within 48 hours of becoming sick.
17. Many will argue that public health measures are the best way to control and prevent the spread of infectious diseases. How can we learn from our past experiences dealing with pandemics?
In the past, public health measures have been relatively successful in moderating and controlling pandemics. When these public health measures were not in place pandemics, such as the Bubonic Plague, ravaged the world’s population. As the world progressed into the modern age, a general trend of less disease related deaths can be seen. This is due to the modern realization of the positive impacts of strong public health measures.
18. What effects have public health measures had on reducing deaths due to infectious disease in the United States? What measures have had the greatest impact?
Public health measures have drastically reduced the number of deaths due to infectious disease. The measures which have had the greatest impact are improvements in basic infrastructure, vaccines, and antibiotics. Some examples of good basic infrastructure are clean water, good sanitation practices, and the fulfillment of nutritional needs.
19. What is epidemiolgy?
Epidemiology is the study of the distribution and determinants of health-related states in specified populations, and the application of this study to control health problems.
20. How have public health measures worked in the past to eradicate disease from parts of the world?
Public health measures have been quite successful in the past. A fine example would be the eradication of smallpox. Smallpox was eradicated from the whole world and the public health measures that accomplished this were very effective. Health organizations around the world cooperated with both the WHO and each other to vaccinate people and get rid of smallpox. Today, only a few samples of the smallpox virus remain in a secure facility where they are being studied to help further our knowledge of disease.
21. What animals are involved in spreading and transmitting avian influenza?
Some animals involved in the spreading and transmitting of avian influenza are pigs, waterfowl (duck/geese), chickens, humans, whales, horses, and seals. They can all contract and transmit the disease.
22. Can this information be used to control the spread of the disease?
All of the above information can be used to control the spread of disease, as we know how avian influenza is given to us and we can counteract it. One of several possible solutions would be to vaccinate the bird or carrier population (a temporary measure at best). Another solution would be to systematically kill off the host population, a technique often used in China.
23. Why is avian influenza spreading so quickly in some regions and not in others? What are some possible ways that it may spread globally?
Avian influenza is spreading faster in some regions as opposed to others because some regions have little to no health measures in place to stop the spread of disease. Many countries in Africa exemplify this lack of preparation for the spread of disease. Another reason may be the high population density of some areas as opposed to others. A couple ways in which avian influenza may spread globally are bird migratory routes, airplanes, shipping, and tourism.
The avian influenza is more threatening than the common flu for several reasons. One is that the avian influenza originated in birds so when it crossed species lines, the virus went haywire since it’s not supposed to occur in other species. Another reason why the avian influenza is more threatening is because of the complications that could occur. When you contract the avian influenza, you could possibly develop pneumonia, respiratory failure, shock, altered mental state, seizures, failure of multiple organs (e.g. kidney failure), and you could die. On the other hand, with the seasonal influenza, or flu, possible complications include pneumonia, bronchitis, and ear infections. Not only are the complications of the common flu less severe, but most people overcome it in a few days to less than two weeks. The avian influenza, on the other hand, is much more severe and can be rapidly fatal. In addition, most people are vaccinated and or immune to the flu whereas people are not vaccinated and no one is immune against the avian flu. Therefore, the avian flu poses a higher risk.
2. How does an influenza virus infect the host cell?
Influenza infects the host cell by going through the cell wall and into the cytoplasm. There it dissolves and spreads its genetic code. Then the virus multiplies, destroys the host cell, and travels to other cells to repeat the process.
3. What kinds of changes must occur to allow avian influenza to be transmitted between individuals of different species, such as from birds to human?
An antigenic shift allows the avian influenza virus to be transmitted across species lines. Antigenic shift occurs since “influenza A viruses have eight separate gene segments. The segmented genome allows influenza A viruses from different species to mix and create a new virus if influenza A viruses from two different species infect the same person or animal.”
4. Can the existing avian influenza virus be transferred from one human host to another? Why or why not?
Yes. It is possible if a person is co-infected with the avian influenza A virus and the human influenza A virus. If this occurs, the genetic information of the two viruses could reassort “to create a new influenza A virus with a hemagglutinin gene from the avian virus and other genes from the human virus. Influenza A viruses with a hemagglutinin (against which humans have little or no immunity) that have reassorted with a human influenza virus are more likely to result in sustained human-to-human transmission and pose a major public health threat of pandemic influenza.”
5. In what regions of the world can avian influenza be found today? Who is most at risk of getting it?
Technically speaking everyone is at risk of getting avian influenza and it is found everywhere. However the newest strain of H7N9 has been found in China but there haven’t been any laboratory confirmed results of human infection.
6. The Spanish Flu epidemic of 1918 demonstrates why microbial evolution is a concern of scientists everywhere. What needs to happen for H5N1 to become a threat to public health?
For H5N1 to become a public health threat, it needs to demonstrate the ability to transmit quickly and effectively through humans, where each infected individual spreads it to many others. The strain also needs to be a more common occurrence in humans and in birds; If it is more common in birds it will be able to spread quickly over the poultry trade routes.
7. How do microbes evolve?
Microbes evolve by mutating and reproducing at a quick rate. When microbes develop a mutation that is resistant to certain drugs, natural selection will allow the microbes to reproduce the mutation more so it becomes common in the host organism. When scientists try to use antivirals on the host, the mutated microbes will spread and grow quicker.
8. Describe why the 1918 Spanish Flu pandemic was such a concern in terms of microbial evolution?
The Spanish Flu had evolved from an avian form of influenza, slowly mutating and spreading through people. As it spread into people, it had become very virulent due to the fact that it was in humans, although being a flu for birds.
9. How does microbial evolution lead to antibiotic and antiviral drug resistance?
They can either spontaneously evolve or become resistant due to a failing immune system allowing them to attack the host, such as HIV. With spontaneous mutations, THEY WILL BECOME PREDOMINANT UPON EXPOSURE TO THE ANTIVIRAL that they evolved resistant to.
10. How does our knowledge of microbial evolution permit a better understanding of the threats posed by avian influenza?
We would be able to detect when it obtains the ability to be easily transmissible between humans and be able to halt or curb its attempt to spread through the human population. We would also be able to detect whether or not a certain vaccine worked or not.
11. Each year a new seasonal flu vaccine is produced to fight the different strains of the virus that threaten to dominate in that particular period. What does this indicate about efforts to develop a vaccine for H5N1?
Each year a new seasonal flu vaccine is produced to fight the different strains of the virus that threaten to dominate that particular period. This indicates that our efforts to develop a vaccine for H5N1 are wasteful. The spending of vaccines yearly for a virus that will change to be resistant the next year is futile. Vaccine making techniques have become more efficient, but in the long run we need a different solution to the vaccination problem. Vaccines are not useless though since they help protect society from disease before they are afflicted.
12. What is a vaccine?
A vaccine is a small dosage of a disease to make your body produce antibodies against the virus.
13. How does a vaccine work with an individual’s immune system to protect an individual against disease?
Vaccines help provide immunity to disease by making the body produce antibodies to protect against the disease.
14. How are vaccines made?
Vaccines are made yearly from the virus that is trying to be defended against. The vaccine is produced from the virus and is injected into the patient in small doses to allow your body to produce antibodies against it.
15. What roles do vaccines play in ensuring the overall health of society?
Vaccines can protect the overall health of a society by increasing herd immunity in a society. Herd immunity is when a percent of a population is vaccinated they can act as buffers to the disease for the people who have not been infected yet.
16. Are there antivirals and vaccines for avian influenza? What needs to be done in order to develop some?
The current antivirals for the avian flu are Tamiflu and Relenza. They are drugs that target proteins in a cell to inhibit the spread of viruses. The antiviral are only effective if they are given within 48 hours of becoming sick.
17. Many will argue that public health measures are the best way to control and prevent the spread of infectious diseases. How can we learn from our past experiences dealing with pandemics?
In the past, public health measures have been relatively successful in moderating and controlling pandemics. When these public health measures were not in place pandemics, such as the Bubonic Plague, ravaged the world’s population. As the world progressed into the modern age, a general trend of less disease related deaths can be seen. This is due to the modern realization of the positive impacts of strong public health measures.
18. What effects have public health measures had on reducing deaths due to infectious disease in the United States? What measures have had the greatest impact?
Public health measures have drastically reduced the number of deaths due to infectious disease. The measures which have had the greatest impact are improvements in basic infrastructure, vaccines, and antibiotics. Some examples of good basic infrastructure are clean water, good sanitation practices, and the fulfillment of nutritional needs.
19. What is epidemiolgy?
Epidemiology is the study of the distribution and determinants of health-related states in specified populations, and the application of this study to control health problems.
20. How have public health measures worked in the past to eradicate disease from parts of the world?
Public health measures have been quite successful in the past. A fine example would be the eradication of smallpox. Smallpox was eradicated from the whole world and the public health measures that accomplished this were very effective. Health organizations around the world cooperated with both the WHO and each other to vaccinate people and get rid of smallpox. Today, only a few samples of the smallpox virus remain in a secure facility where they are being studied to help further our knowledge of disease.
21. What animals are involved in spreading and transmitting avian influenza?
Some animals involved in the spreading and transmitting of avian influenza are pigs, waterfowl (duck/geese), chickens, humans, whales, horses, and seals. They can all contract and transmit the disease.
22. Can this information be used to control the spread of the disease?
All of the above information can be used to control the spread of disease, as we know how avian influenza is given to us and we can counteract it. One of several possible solutions would be to vaccinate the bird or carrier population (a temporary measure at best). Another solution would be to systematically kill off the host population, a technique often used in China.
23. Why is avian influenza spreading so quickly in some regions and not in others? What are some possible ways that it may spread globally?
Avian influenza is spreading faster in some regions as opposed to others because some regions have little to no health measures in place to stop the spread of disease. Many countries in Africa exemplify this lack of preparation for the spread of disease. Another reason may be the high population density of some areas as opposed to others. A couple ways in which avian influenza may spread globally are bird migratory routes, airplanes, shipping, and tourism.