AFS 190 COVID series quiz 1
Various methods could be used to prevent a large pandemic flu outbreak including the culling of infected reservoir species (such as bird) early detection, and effective quarantine of infected humans. China responded in February 2020 to destroy much of its commercial wild animal farming market. Vaccines, would also be effective which could be made to protect against newly emergent viruses, however
a vaccine probably would not be available in the early stages of a pandemic
Some say that we have entered a new Phase of the COVID-19 pandemic where the SARS-CoV-2 virus is now endemic to humans on the planet. An endemic disease is one that is:
constantly present to a greater or lesser degree in the population everywhere on earth.
Pandemics can occur when a new strain of the virus is transmitted to humans from another animal species. These are called zoonotic viruses. Reservoir species that are thought to be important in the emergence of new strains of viruses are, bats, civet cats, pangoline and sometimes other primates and birds. How mutations in the viral genome result in new virulent viruses is a research topic of concern. Changes in the viral genome result in a new virus subtypes. The appearance of a new virus subtype is the first step toward a pandemic; however, to cause a pandemic, the new virus subtype also must
have the capacity to spread easily from person-to-person
Many human infections involve human-to-human transmission. During the early 20th century the Spanish flu swept across the world in one year. Technology has changed our world since those times. How will the next major global pandemic most likely move most effectively?
human to human transmission facilitated by air travel
Many patients with the flu or COVID visit their physician and request an antibiotic. Antibiotics are effective against microbial infections, but are not useful against viruses. Antiviral medications have been made and tested to prevent and treat influenza
including four different influenza antiviral medications (amantadine, rimantadine, oseltamivir, and zanamivir)
A pandemic is a global outbreak of disease that occurs when a new virus appears or "emerges" often from a non-human source which crosses over to become infectious in the human population, causes serious illness, and then spreads easily from person to person worldwide. A pandemic
is likely to occur again in the future and has occurred several time in the last 100 years with devastating consequences
In the WHO Stages of a Pandemic, Phase 1 is characterized as: having no new virus subtypes that have been yet detected in humans; A novel virus subtype that has caused human infection may be present in animals, but here is no human-to-human transmission. If present in animals, the risk of human infection or disease is considered to be:
low, but mutations are continuing in the viral reservoir and should be monitored
Pandemics follow various stages of development. The stages of a Pandemic, characterized by the World Health Organization (WHO) recognizes a Phase 6 Pandemic when:
sustained transmission in general populations through increased human to human transmission
During the 20th century, the emergence of several new influenza A virus subtypes have caused pandemics; all of which spread around the world within a year of being detected. One of these is suspected of killing over 675,000 in the US and perhaps over 70 million globally. That deadly pandemic was called the
1918-19, "Spanish flu," [A (H1N1)]
Each year a new seasonal flu vaccine is developed based on screening of various circulating viruses. Some say that we may now require the same for COVID-19 and its variants. Who is monitoring global emergence of viruses?
The World Health Organization (WHO) and the various global Centers for Disease Control and Prevention (CDC)
In 2002 researchers at SUNY Stony Brook succeeded in synthesizing the 7741 base polio virus genome from its published sequence, producing a functional polio synthetic genome. Similarly, work on the virulence genes in influenza viruses has sparked controversy that this type of research could provide new information to prevent new disease or used to create bioweapons. The Dual Use Dilemma refers to:
The basic research on viral genetics and transmissibility that could be used to combat pandemics and the use of that knowledge for the creation of bioweapons.
Many people are familiar with the symptoms of seasonal flu outbreaks. Influenza (also known as the flu) is a contagious respiratory illness caused by various types of flu viruses. It can cause mild to severe illness, and at times can lead to death. The flu is different from a cold. The patient typically first feels 'out of sorts' as if first becoming ill. The percentage of the U.S. population that will get the flu, on average, each year is 5% to 20%. The average number of Americans hospitalized each year because of problems with the illness is 200,000 and the number of people who die each year from flu-related causes in the U.S is 3,000 to 49,000. The year of 2020-21 has seen very low flu cases. The best way to protect from contracting the flu is
all of the above
A novel Influenza A virus was first detected in Hong Kong in early 1968 and spread to the United States later that year. The estimated number of deaths was 1 million worldwide and about 100,000 in the United States. At the time the pandemic
all of these
A zoonotic pathogen is a disease spread between animals and people. Zoonotic diseases can be caused by viruses, bacteria, parasites, and fungi. Some of these diseases are familiar and include
all of these
A pandemic is a global epidemic of an emergent virus that spreads on a worldwide scale and infects a large proportion of the world population. In contrast to the regular seasonal epidemics of influenza, these pandemics occur irregularly. A flu pandemic occurs when a new influenza virus emerges for which people have little or no immunity and for which there is no vaccine. Pandemic flu:
are outbreaks that are caused by new influenza subtypes that have never circulated among people or by subtypes that have not circulated among people for a long time
Viruses that can cause flu in humans circulate each year. There are many different subtypes of Influenza or "flu" viruses. The subtypes differ based upon certain proteins on the surface of the virus are used to classify the subtypes are designated
as HN based on the hemagglutinin or "HA" protein and the neuraminidase or the "NA" protein.
Pandemic viruses emerge as a result of a process called "antigenic shift," which causes an abrupt or sudden, major change in influenza A viruses. As billions of viruses replicate, mutations can cause variation in infectivity. These changes are caused by
the process of viral evolution and selection for replication as observed in new combinations of genes and mutations in viral coat proteins on the surface of the virus
How do new viruses evolve? Certainly, one mechanism involves mutation of individual bases in the viral genome which occur during replication. The emergence of several new influenza A virus subtypes have caused pandemics throughout recent history; one other important clue about their origins is that
the viruses contain a combination of human and/or animal host species genes or changes in the genes which encode recognition of their receptors
The screening and detection of specific DNA sequences has been broadly applied in medical and life sciences. In the first part of this course we examined the method of PCR. PCR has proven to be an essential molecular tool for use in COVID-19 testing and vaccine development.
true