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Covid Vaccine

"yEaH, bUt tHe PoLiO vAcCiNe DoEz NoT PrEvEnT PoLLiO, iT JuSt LoWeRs EfFeCtZ oF tHe PoOLiO!"
- Dr. Flogstain von Booster Shortbus
aNd It DoNt Be prevInT NoOne eLsE fRom GeTtiNg ThE LiO!
/Flog, DeadDogDragger Extraordinaire, 19x TopChef Pangolin Version Award Winner, Guinness Book Record Holder for Most DingDongs consumed during a Bluey episode
 

List of Vaccines Used in United States​


  • Adenovirus
  • Anthrax
    • AVA (BioThrax)
  • Cholera
    • Vaxchora
  • Diphtheria
    • DTaP (Daptacel, Infanrix)
    • Td (Tenivac, generic)
    • Tdap (Adacel, Boostrix)
    • DTaP-IPV (Kinrix, Quadracel)
    • DTaP-HepB-IPV (Pediarix)
    • DTaP-IPV/Hib (Pentacel)
    • DTaP-IPV-Hib-HepB (Vaxelis)
  • Hepatitis A
    • HepA (Havrix, Vaqta)
    • HepA-HepB (Twinrix)
  • Hepatitis B
    • HepB (Engerix-B, Recombivax HB, Heplisav-B)
    • DTaP-HepB-IPV (Pediarix)
    • HepA-HepB (Twinrix)
    • DTaP-IPV-Hib-HepB (Vaxelis)
  • Haemophilus influenzae type b (Hib)
    • Hib (ActHIB, PedvaxHIB, Hiberix)
    • DTaP-IPV/Hib (Pentacel)
    • DTaP-IPV-Hib-HepB (Vaxelis)
  • Human Papillomavirus (HPV)
    • HPV9 (Gardasil 9) (For scientific papers, the preferred abbreviation is 9vHPV)
  • Seasonal Influenza (Flu) only
    • IIV* (Afluria, Fluad, Flublok, Flucelvax, FluLaval, Fluarix, Fluvirin, Fluzone, Fluzone High-Dose, Fluzone Intradermal)
      *There are various acronyms for inactivated flu vaccines – IIV3, IIV4, RIV3, RIV4 and ccIIV4.
    • LAIV (FluMist)
  • Japanese Encephalitis
    • JE (Ixiaro)
  • Measles
    • MMR (M-M-R II, Priorix)
    • MMRV (ProQuad)
  • Meningococcal
    • MenACWY (Menactra, MenQuadfi, Menveo)
    • MenB (Bexsero, Trumenba)
  • Mumps
    • MMR (M-M-R II, Priorix)
    • MMRV (ProQuad)
  • Pertussis
    • DTaP (Daptacel, Infanrix)
    • Tdap (Adacel, Boostrix)
    • DTaP-IPV (Kinrix, Quadracel)
    • DTaP-HepB-IPV (Pediarix)
    • DTaP-IPV/Hib (Pentacel)
    • DTaP-IPV-Hib-HepB (Vaxelis)
  • Pneumococcal
    • PCV13 (Prevnar13)
    • PCV15 (Vaxneuvance)
    • PCV20 (Prevnar20)
    • PPSV23 (Pneumovax 23)
  • Polio
    • Polio (Ipol)
    • DTaP-IPV (Kinrix, Quadracel)
    • DTaP-HepB-IPV (Pediarix)
    • DTaP-IPV/Hib (Pentacel)
    • DTaP-IPV-Hib-HepB (Vaxelis)
  • Rabies
    • Rabies (Imovax Rabies, RabAvert)
  • Rotavirus
    • RV1 (Rotarix)
    • RV5 (RotaTeq)
  • Rubella
    • MMR (M-M-R II, Priorix)
    • MMRV (ProQuad)
  • Shingles
    • RZV (Shingrix)
  • Smallpox
    • Vaccinia (ACAM2000):
  • Tetanus
    • DTaP (Daptacel, Infanrix)
    • Td (Tenivac, generic)
    • Tdap (Adacel, Boostrix)
    • DTaP-IPV (Kinrix, Quadracel)
    • DTaP-HepB-IPV (Pediarix)
    • DTaP-IPV/Hib (Pentacel)
    • DTaP-IPV-Hib-HepB (Vaxelis)
  • Tuberculosis
  • Typhoid Fever
    • Typhoid Oral (Vivotif)
    • Typhoid Polysaccharide (Typhim Vi)
  • Varicella
    • VAR (Varivax)
    • MMRV (ProQuad):
  • Yellow Fever
    • YF (YF-Vax)


So the flu vaccine is a vaccine even though it was only 60% effective in 2023? Your politics is showing.
 
So the flu vaccine is a vaccine even though it was only 60% effective in 2023? Your politics is showing.
show me where people have been cancelled, forced to leave their jobs, or mandated to get the Flu vaccine.

your tard is showing.
 
show me where people have been cancelled, forced to leave their jobs, or mandated to get the Flu vaccine.

your tard is showing.
So because it was mandated, the Covid vaccine isn’t a vaccine? Retarded is completely forgetting what it is you’re arguing.
 
So because it was mandated, the Covid vaccine isn’t a vaccine? Retarded is completely forgetting what it is you’re arguing.
you change and deflect without answering anything, as has been your modus operandi for 800+ pages now.

You ask for "a"
and then "a" is provided
you ask for "b"
and then "b" is provided
you screech for "sources"
"sources" is provided
You ask for "a"
and then "a" is provided
you ask for "b"
and then "b" is provided
you screech for "sources"
"sources" is provided
You ask for "a"
and then "a" is provided
you ask for "b"
and then "b" is provided
you screech for "sources"
"sources" is provided
You ask for "a"
and then "a" is provided
you ask for "b"
and then "b" is provided
you screech for "sources"
"sources" is provided
You ask for "a"
and then "a" is provided
you ask for "b"
and then "b" is provided
you screech for "sources"
"sources" is provided
You ask for "a"
and then "a" is provided
you ask for "b"
and then "b" is provided
you screech for "sources"
"sources" is provided
You ask for "a"
and then "a" is provided
you ask for "b"
and then "b" is provided
you screech for "sources"
"sources" is provided

800+ pages

meanwhile, your clot shot is proving to be less effective than you and I and the world were told, people are suffering after having taken the holy heart stopping shot, people were mandated to take the shot that isnt as effective as the world was told - some died, but you couldn't care less since people always die - the manufacturers of the shots are admitting that the shots were rolled out under false pretenses, booster after booster is rolled out... and you want to hang your tard on any typographical or superficial "error".

so tell the class - and this is since YOU brought it up -
  • do we have Flu vaccine BOOSTER shots?
  • are we told that the flu vaccine is going to keep you from getting the flu and spreading the flu?
  • are we required to get a Flu vaccine?
  • did the economy shut down over the Flu?
  • does the definition of vaccine change during Flu season?
and since we all know you cannot and will not answer any direct question, you can copy from below:
  • No, we do not
  • No, we all know that the Flu vaccine is only for this variant of the Flu and you will likely get sick but not as sick
  • No, we are not
  • No, it did not
  • No, it does not
Compare and contrast that to the WooFloo, you dead dog dragging, 25-mask wearing, ice cream chugging retarded tub of lard

 
“Actual vaccines”, “it’s a shot, not a vaccine” talk about idiocy.

List the actual vaccines.

Yet, again, another deflection to another inane point.

What drug, Dr. Flogstain, prevents exposure? Who here has ever claimed a drug did/does prevent against exposure?
 
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😂 Again. Any reasonable person can look at the FULL statement, compare it to what was quoted on social media, and see quite clearly, she was being taken out of context. Not you. Your delusion is strong.


Nothing...let me repeat - NOTHING she said in that full minute changes the intent of what she said.

A). She knew the vaccines wouldn't prevent spread. What in this mystifying context you speak of changes that statement?
B). She said the Government overplayed the vaccines. What in this mystifying context you speak of changes that statement?

Both things she said are indeed true and no PolitiWhack fact check or link to any other conversation, interview, discussion she's had changes that very simple message. She knew they wouldn't prevent spread (that's true, she was right) and the Government overplayed (lied) about the vaccine's potential (that's true, she was right).
 
Did the CDC change the definition of vaccine during the Pandemic? Yes or No?

giphy.gif
 
you change and deflect without answering anything, as has been your modus operandi for 800+ pages now.

You ask for "a"
and then "a" is provided
you ask for "b"
and then "b" is provided
you screech for "sources"
"sources" is provided
You ask for "a"
and then "a" is provided
you ask for "b"
and then "b" is provided
you screech for "sources"
"sources" is provided
You ask for "a"
and then "a" is provided
you ask for "b"
and then "b" is provided
you screech for "sources"
"sources" is provided
You ask for "a"
and then "a" is provided
you ask for "b"
and then "b" is provided
you screech for "sources"
"sources" is provided
You ask for "a"
and then "a" is provided
you ask for "b"
and then "b" is provided
you screech for "sources"
"sources" is provided
You ask for "a"
and then "a" is provided
you ask for "b"
and then "b" is provided
you screech for "sources"
"sources" is provided
You ask for "a"
and then "a" is provided
you ask for "b"
and then "b" is provided
you screech for "sources"
"sources" is provided

800+ pages

meanwhile, your clot shot is proving to be less effective than you and I and the world were told, people are suffering after having taken the holy heart stopping shot, people were mandated to take the shot that isnt as effective as the world was told - some died, but you couldn't care less since people always die - the manufacturers of the shots are admitting that the shots were rolled out under false pretenses, booster after booster is rolled out... and you want to hang your tard on any typographical or superficial "error".

so tell the class - and this is since YOU brought it up -
  • do we have Flu vaccine BOOSTER shots?
Yes. Every fall.
  • are we told that the flu vaccine is going to keep you from getting the flu and spreading the flu?
Yes, the very point of getting it.
  • are we required to get a Flu vaccine?
Many healthcare personnel are required to “jump through hoops” if they opt not to get it.
  • did the economy shut down over the Flu?
  • does the definition of vaccine change during Flu season?
and since we all know you cannot and will not answer any direct question, you can copy from below:
  • No, we do not
  • No, we all know that the Flu vaccine is only for this variant of the Flu and you will likely get sick but not as sick
  • No, we are not
  • No, it did not
  • No, it does not
Compare and contrast that to the WooFloo, you dead dog dragging, 25-mask wearing, ice cream chugging retarded tub of lard

 
“Actual vaccines”, “it’s a shot, not a vaccine” talk about idiocy.

List the actual vaccines.

He did.

So the flu vaccine is a vaccine even though it was only 60% effective in 2023? Your politics is showing.

No, the flu vaccine is only 60% effective because there are hundreds of variations of the flu, and if you are exposed to a flu not based on the flu for the vaccine you took, it won't work.

So because it was mandated, the Covid vaccine isn’t a vaccine? Retarded is completely forgetting what it is you’re arguing.

No, the shotz/vax is not a vaccine because it does not prevent you from getting the disease the shotz/vax is supposed to prevent you from getting, or from spreading the disease the shotz/vax was supposed to prevent you from spreading.

Like every other vaccine that works by preventing you from getting the disease or from spreading it because you don't get it.
 
So the flu vaccine is a vaccine even though it was only 60% effective in 2023? Your politics is showing.
It is a shot (in the dark most years), and us only called a vaccine because the pFDA pFuckers changed the definition twice in the past decade.

Shame on conmen shills like you
 

List of Vaccines Used in United States​


  • Adenovirus
  • Anthrax
    • AVA (BioThrax)
  • Cholera
    • Vaxchora
  • Diphtheria
    • DTaP (Daptacel, Infanrix)
    • Td (Tenivac, generic)
    • Tdap (Adacel, Boostrix)
    • DTaP-IPV (Kinrix, Quadracel)
    • DTaP-HepB-IPV (Pediarix)
    • DTaP-IPV/Hib (Pentacel)
    • DTaP-IPV-Hib-HepB (Vaxelis)
  • Hepatitis A
    • HepA (Havrix, Vaqta)
    • HepA-HepB (Twinrix)
  • Hepatitis B
    • HepB (Engerix-B, Recombivax HB, Heplisav-B)
    • DTaP-HepB-IPV (Pediarix)
    • HepA-HepB (Twinrix)
    • DTaP-IPV-Hib-HepB (Vaxelis)
  • Haemophilus influenzae type b (Hib)
    • Hib (ActHIB, PedvaxHIB, Hiberix)
    • DTaP-IPV/Hib (Pentacel)
    • DTaP-IPV-Hib-HepB (Vaxelis)
  • Human Papillomavirus (HPV)
    • HPV9 (Gardasil 9) (For scientific papers, the preferred abbreviation is 9vHPV)
  • Seasonal Influenza (Flu) only
    • IIV* (Afluria, Fluad, Flublok, Flucelvax, FluLaval, Fluarix, Fluvirin, Fluzone, Fluzone High-Dose, Fluzone Intradermal)
      *There are various acronyms for inactivated flu vaccines – IIV3, IIV4, RIV3, RIV4 and ccIIV4.
    • LAIV (FluMist)
  • Japanese Encephalitis
    • JE (Ixiaro)
  • Measles
    • MMR (M-M-R II, Priorix)
    • MMRV (ProQuad)
  • Meningococcal
    • MenACWY (Menactra, MenQuadfi, Menveo)
    • MenB (Bexsero, Trumenba)
  • Mumps
    • MMR (M-M-R II, Priorix)
    • MMRV (ProQuad)
  • Pertussis
    • DTaP (Daptacel, Infanrix)
    • Tdap (Adacel, Boostrix)
    • DTaP-IPV (Kinrix, Quadracel)
    • DTaP-HepB-IPV (Pediarix)
    • DTaP-IPV/Hib (Pentacel)
    • DTaP-IPV-Hib-HepB (Vaxelis)
  • Pneumococcal
    • PCV13 (Prevnar13)
    • PCV15 (Vaxneuvance)
    • PCV20 (Prevnar20)
    • PPSV23 (Pneumovax 23)
  • Polio
    • Polio (Ipol)
    • DTaP-IPV (Kinrix, Quadracel)
    • DTaP-HepB-IPV (Pediarix)
    • DTaP-IPV/Hib (Pentacel)
    • DTaP-IPV-Hib-HepB (Vaxelis)
  • Rabies
    • Rabies (Imovax Rabies, RabAvert)
  • Rotavirus
    • RV1 (Rotarix)
    • RV5 (RotaTeq)
  • Rubella
    • MMR (M-M-R II, Priorix)
    • MMRV (ProQuad)
  • Shingles
    • RZV (Shingrix)
  • Smallpox
    • Vaccinia (ACAM2000):
  • Tetanus
    • DTaP (Daptacel, Infanrix)
    • Td (Tenivac, generic)
    • Tdap (Adacel, Boostrix)
    • DTaP-IPV (Kinrix, Quadracel)
    • DTaP-HepB-IPV (Pediarix)
    • DTaP-IPV/Hib (Pentacel)
    • DTaP-IPV-Hib-HepB (Vaxelis)
  • Tuberculosis
  • Typhoid Fever
    • Typhoid Oral (Vivotif)
    • Typhoid Polysaccharide (Typhim Vi)
  • Varicella
    • VAR (Varivax)
    • MMRV (ProQuad):
  • Yellow Fever
    • YF (YF-Vax)


Since you are so good at this stuff, can you pls find an ordered list of these vaxes with efficacy or safety? Like which one is best or worst, and which one is safest or the least safe?

Folks want to know!!!
 
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Mom and Dad got the clot shot...

EXCLUSIVEUltra rare 'spider twins' have three legs, four arms and one penis​

By EMILY JOSHU HEALTH REPORTER FOR DAILYMAIL.COM

PUBLISHED: 21:00 EDT, 14 May 2024 | UPDATED: 04:50 EDT, 15 May 2024





After defying the odds and surviving gestation and child birth, the toddlers were unable to sit up and forced to lie flat for the first three years of their life.
A team of surgeons performed a painstaking operation to amputate their third leg and stabilize their hip and pelvic bone so they could sit upright and give them some semblance of normalcy.

Top doctor is cancer-free after treatment based on his own research
28.7k viewing now
Their condition has led to them being conjoined like a spider, a term coined by famous conjoined twins Ganga and Jamuna Mondal of India.
Conjoined twins account for one in 50,000 to 200,000 live births and occur when a single fertilized egg splits and develops into two individuals.
About eight to 12 days after being conceived, the layers that split to form identical twins develop into specific organs and structures, according to the Mayo Clinic.
It is believed that the process ends prematurely, resulting in conjoined twins.
However, another theory suggests that two separate embryos fuse together early in development.

Female conjoined twins tend to outweigh males 3:1. And in two-thirds of cases, at least one twins either dies or is stillborn.
The Indonesian twins are Ischiopagus Tripus, meaning that they are joined at the pelvis.
The boys were born with four functioning arms, two functioning legs, and one nonfuctional leg. They also share one penis and anus.
Doctors believe one of the twins had an underdeveloped kidney, known as left kidney hypoplasia, while the other only had one kidney.
Their parents had two older children, and there was no family history of medical issues. Their mother reported no complications during her pregnancy.
Researchers have noted that only a handful of cases have been reported in medical literature. The team in Indonesia estimated that six to 11 percent of all conjoined twins are Ischiopagus.
It's unclear how long the surgery took, but the twins suffered no complications after or as of a three-month follow-up. The surgery allowed them to be able to sit up and potentially stand, offering them more independence.
One case report of conjoined twins in Pakistan showed one twin severely underdeveloped. Both died before they could be separated

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One case report of conjoined twins in Pakistan showed one twin severely underdeveloped. Both died before they could be separated
Twin boys born in 1989 in Pakistan were separated as toddlers in a nearly 10-hour procedure

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View gallery
Twin boys born in 1989 in Pakistan were separated as toddlers in a nearly 10-hour procedure
The boys are two of only a handful of Ischiopagus Tripus conjoined twins to be successfully separated

+4
View gallery
The boys are two of only a handful of Ischiopagus Tripus conjoined twins to be successfully separated
There have only been a handful of reports published on Ischiopagus Tripus conjoined twins. Many of those available focus on twins who were separated.
One novel report from 1994 detailed a pair of such twins who were born in China in 1989. They each had two normally functioning arms, two working legs, and one nonresponsive fused leg. The boys also had one penis and two testes but no anus.
Doctors separated them in 1992 when they were just over two years old. The operation took nearly 10 hours.
Another case study focused on one pair of conjoined twins born in Pakistan in 2011. They were fused together at the lower half of their bodies, and one twin was significantly smaller, more feeble, and had a smaller head.
Their genitalia was not developed enough to assign a gender to either twin, and there was no clear anus. They both died before they could be separated.
The new case report was published in the American Journal of Case Reports.
 
No, the flu vaccine is only 60% effective because there are hundreds of variations of the flu, and if you are exposed to a flu not based on the flu for the vaccine you took, it won't work.
If by hundreds, you mean “two”, yes. H1N1 and H3N2
No, the shotz/vax is not a vaccine because it does not prevent you from getting the disease the shotz/vax is supposed to prevent you from getting, or from spreading the disease the shotz/vax was supposed to prevent you from spreading.

Like every other vaccine that works by preventing you from getting the disease or from spreading it because you don't get it.
Ohhhhh….
 
That's a nice chart. Less Measles is very good for young people.

But what is the efficacy of each vaccine? What is the safety? Which one is best? Which is the worst?
ze bess is tha ClotShot! works on errythang! Covid, WooFloo, BatFloo, measles, mumps, pumps, chumps, large areolas, small areolas, high blood pressure, low tire pressure, gout, clout, mustaches, ear worms... errythang! 102.7% effective on anyerrythang.
 
ze bess is tha ClotShot! works on errythang! Covid, WooFloo, BatFloo, measles, mumps, pumps, chumps, large areolas, small areolas, high blood pressure, low tire pressure, gout, clout, mustaches, ear worms... errythang! 102.7% effective on anyerrythang.
Reminds me of this classic line ..

 
Hey! Wait your turn there buddy! There is like 12 ahead of you in the queue awaiting a direct answer.

Kids these days...how rude! :ROFLMAO:
12?

Let's see, 847 pages averaging 2 unanswered direct questions per page, you're looking at about 1,700 at this point, which is why this troll has no credibility what so ever.
 
If by hundreds, you mean “two”, yes. H1N1 and H3N2

Ohhhhh….
wrong again, dipshit.


Types of Influenza Viruses​

There are four types of influenza viruses: A, B, C, and D. Influenza A and B viruses cause seasonal epidemics of disease in people (known as flu season) almost every winter in the United States. Influenza A viruses are the only influenza viruses known to cause flu pandemics (i.e., global epidemics of flu disease). A pandemic can occur when a new and different influenza A virus emerges that infects people, has the ability to spread efficiently among people, and against which people have little or no immunity. Influenza C virus infections generally cause mild illness and are not thought to cause human epidemics. Influenza D viruses primarily affect cattle with spillover to other animals but are not known to infect people to cause illness.

Influenza A viruses are divided into subtypes based on two proteins on the surface of the virus: hemagglutinin (H) and neuraminidase (N). There are 18 different hemagglutinin subtypes and 11 different neuraminidase subtypes (H1 through H18 and N1 through N11, respectively). While more than 130 influenza A subtype combinations have been identified in nature, primarily from wild birds, there are potentially many more influenza A subtype combinations given the propensity for virus “reassortment.” Reassortment is a process by which influenza viruses swap gene segments. Reassortment can occur when two influenza viruses infect a host at the same time and swap genetic information. Current subtypes of influenza A viruses that routinely circulate in people include A(H1N1) and A(H3N2). Influenza A subtypes can be further broken down into different genetic “clades” and “sub-clades.” See the “Influenza Viruses” graphic below for a visual depiction of these classifications.

Clades and sub-clades can be alternatively called “groups” and “sub-groups,” respectively. An influenza clade or group is a further subdivision of influenza viruses (beyond subtypes or lineages) based on the similarity of their HA gene sequences. (See the Genome Sequencing and Genetic Characterization page for more information). Clades and subclades are shown on phylogenetic trees as groups of viruses that usually have similar genetic changes (i.e., nucleotide or amino acid changes) and have a single common ancestor represented as a node in the tree (see Figure 1). Dividing viruses into clades and subclades helps flu experts track the proportion of viruses from different clades in circulation.

Note that clades and sub-clades that are genetically different from others are not necessarily antigenically different. This is best understood by first introducing the concepts of “antigens” and “antigenic properties”. As previously described, flu viruses have hemagglutinin (H) and neuraminidase (N) surface proteins. These proteins act as antigens. Antigens are molecular structures on the surface of viruses that are recognized by the immune system and can trigger an immune response (such as antibody production). The antigenic properties are a reflection of the antibody or immune response triggered by the antigens on a particular virus. When two flu viruses are antigenically different, this means that a host’s immune response (antibodies) elicited by infection or vaccination with one of the viruses will not as easily recognize and neutralize the other virus. Therefore, for antigenically different viruses, immunity developed against one of the viruses will not necessarily protect against the other virus as well.

Conversely, when two flu viruses are antigenically similar, a host’s immune response (antibodies) elicited by infection or vaccination with one of the viruses will recognize and neutralize the other virus, thereby protecting against the other virus.

Currently circulating influenza A(H1N1) viruses are related to the pandemic 2009 H1N1 virus that emerged in the spring of 2009 and caused a flu pandemic (CDC 2009 H1N1 Flu website). These viruses, scientifically called the “A(H1N1)pdm09 virus,” and more generally called “2009 H1N1,” have continued to circulate seasonally since then and have undergone genetic changes and changes to their antigenic properties (i.e., the properties of the virus that affect immunity).

Influenza A(H3N2) viruses also change both genetically and antigenically. Influenza A(H3N2) viruses have formed many separate, genetically different clades in recent years that continue to co-circulate.

Influenza B viruses are not divided into subtypes, but instead are further classified into two lineages: B/Yamagata and B/Victoria. Similar to influenza A viruses, influenza B viruses can then be further classified into specific clades and sub-clades. Influenza B viruses generally change more slowly in terms of their genetic and antigenic properties than influenza A viruses, especially influenza A(H3N2) viruses. Influenza surveillance data from recent years shows co-circulation of influenza B viruses from both lineages in the United States and around the world. However, the proportion of influenza B viruses from each lineage that circulate can vary by geographic location and by season. In recent years, flu B/Yamagata viruses have circulated much less frequently in comparison to flu B/Victoria viruses globally.
 
wrong again, dipshit.


Types of Influenza Viruses​

There are four types of influenza viruses: A, B, C, and D. Influenza A and B viruses cause seasonal epidemics of disease in people (known as flu season) almost every winter in the United States. Influenza A viruses are the only influenza viruses known to cause flu pandemics (i.e., global epidemics of flu disease). A pandemic can occur when a new and different influenza A virus emerges that infects people, has the ability to spread efficiently among people, and against which people have little or no immunity. Influenza C virus infections generally cause mild illness and are not thought to cause human epidemics. Influenza D viruses primarily affect cattle with spillover to other animals but are not known to infect people to cause illness.

Influenza A viruses are divided into subtypes based on two proteins on the surface of the virus: hemagglutinin (H) and neuraminidase (N). There are 18 different hemagglutinin subtypes and 11 different neuraminidase subtypes (H1 through H18 and N1 through N11, respectively). While more than 130 influenza A subtype combinations have been identified in nature, primarily from wild birds, there are potentially many more influenza A subtype combinations given the propensity for virus “reassortment.” Reassortment is a process by which influenza viruses swap gene segments. Reassortment can occur when two influenza viruses infect a host at the same time and swap genetic information. Current subtypes of influenza A viruses that routinely circulate in people include A(H1N1) and A(H3N2). Influenza A subtypes can be further broken down into different genetic “clades” and “sub-clades.” See the “Influenza Viruses” graphic below for a visual depiction of these classifications.

Clades and sub-clades can be alternatively called “groups” and “sub-groups,” respectively. An influenza clade or group is a further subdivision of influenza viruses (beyond subtypes or lineages) based on the similarity of their HA gene sequences. (See the Genome Sequencing and Genetic Characterization page for more information). Clades and subclades are shown on phylogenetic trees as groups of viruses that usually have similar genetic changes (i.e., nucleotide or amino acid changes) and have a single common ancestor represented as a node in the tree (see Figure 1). Dividing viruses into clades and subclades helps flu experts track the proportion of viruses from different clades in circulation.

Note that clades and sub-clades that are genetically different from others are not necessarily antigenically different. This is best understood by first introducing the concepts of “antigens” and “antigenic properties”. As previously described, flu viruses have hemagglutinin (H) and neuraminidase (N) surface proteins. These proteins act as antigens. Antigens are molecular structures on the surface of viruses that are recognized by the immune system and can trigger an immune response (such as antibody production). The antigenic properties are a reflection of the antibody or immune response triggered by the antigens on a particular virus. When two flu viruses are antigenically different, this means that a host’s immune response (antibodies) elicited by infection or vaccination with one of the viruses will not as easily recognize and neutralize the other virus. Therefore, for antigenically different viruses, immunity developed against one of the viruses will not necessarily protect against the other virus as well.

Conversely, when two flu viruses are antigenically similar, a host’s immune response (antibodies) elicited by infection or vaccination with one of the viruses will recognize and neutralize the other virus, thereby protecting against the other virus.

Currently circulating influenza A(H1N1) viruses are related to the pandemic 2009 H1N1 virus that emerged in the spring of 2009 and caused a flu pandemic (CDC 2009 H1N1 Flu website). These viruses, scientifically called the “A(H1N1)pdm09 virus,” and more generally called “2009 H1N1,” have continued to circulate seasonally since then and have undergone genetic changes and changes to their antigenic properties (i.e., the properties of the virus that affect immunity).

Influenza A(H3N2) viruses also change both genetically and antigenically. Influenza A(H3N2) viruses have formed many separate, genetically different clades in recent years that continue to co-circulate.

Influenza B viruses are not divided into subtypes, but instead are further classified into two lineages: B/Yamagata and B/Victoria. Similar to influenza A viruses, influenza B viruses can then be further classified into specific clades and sub-clades. Influenza B viruses generally change more slowly in terms of their genetic and antigenic properties than influenza A viruses, especially influenza A(H3N2) viruses. Influenza surveillance data from recent years shows co-circulation of influenza B viruses from both lineages in the United States and around the world. However, the proportion of influenza B viruses from each lineage that circulate can vary by geographic location and by season. In recent years, flu B/Yamagata viruses have circulated much less frequently in comparison to flu B/Victoria viruses globally.

"sO YoU;Re SaYyiNg ThErE aRe TwO FLuEs, A aNd b JuSt LiKe I sAyD??"
- Dr. Flogstain, ded dog dragger, walking champion, golf course trespasser, Dollah Gen'ral expert, Covid expert, shotz/vax expert, and math instructor
 
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