Sunday, October 1, 2023

Flu Virus A And B

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How Can I Help Prevent The Flu In My Child

Influenza A and B Infection and Replication

The best way to prevent flu is to have the yearly flu vaccine. The flu vaccine is given as a shot . A nasal spray is not recommended for the 2017-2018 flu season. The CDC says this is because the nasal spray did not seem to protect against the flu over the last several flu seasons.

Each year, a new flu vaccine is available before the start of the flu season. Talk with your healthcare provider if you have questions about how vaccines work and how well they prevent flu. The first time a child between the ages of 6 months and 8 years gets a flu vaccine, he or she will need a second flu vaccine one month later.

The vaccine is advised for all children 6 months and older. But for some children, its more critical for them to get a flu shot. The flu shot should be given to any child who has any of these:

  • A long-term heart or lung condition

  • An endocrine disorder such as diabetes

  • A kidney or liver disorder

  • Weak immune system from HIV/AIDS or long-term steroids

  • A blood disorder such as sickle cell disease

A flu shot should also be given to:

  • A child who has a family member with a chronic health condition

  • A child or teen taking aspirin as long-term therapy

  • A child with parents or caregivers at high risk of complications from the flu

Some side effects of the vaccine can be like mild flu symptoms, but the vaccine does not cause the flu. Possible side effects of the flu vaccine include:

And you can help prevent your child spreading the flu to others if you:

When To See A Doctor For Influenza A Or B

A majority of people will ride out the flu from home with only mild-to-moderate symptoms. But sometimes its better to visit your healthcare provider. Anyone with one or more of the risk factors for complications listed above should consider seeing a professional to make sure it doesnt evolve into a more severe disease or respiratory infection.

A healthcare provider might also be necessary for individuals with severe or prolonged symptoms or other complications like difficulty breathing, chest pain, sudden dizziness, vomiting, neck stiffness, or loss of consciousness.

Infection And Infectious Disease

Influenza viruses are assumed to be transmitted predominantly by aerosol infection, i.e. relatively large droplets created particularly while talking, coughing, or sneezing, thus entering the mucosae through contact at small distances. Individual publications, however, have also suggested that transmission might occur by socalled droplet cores which are smaller and able to remain in the air for longer periods . In addition, transmission can occur by direct contact with virus-contaminated surfaces and subsequent mouth-nose contact. After infection the viruses replicate in the nasal and laryngeal mucosae. This replication also affects the lower airways as the infection progresses.

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Which Type Of Bird Flu Is In The News

Health care professionals had been very vocal about the strain of avian influenza known as H5N1.

The reason H5N1 has caused so much alarm is its ability to pass from wild birds to poultry and then on to people. While wild birds are commonly immune to the devastating and possibly deadly effects of H5N1, the virus has killed more than half of the people infected with it. The risk of avian flu is generally low in most people because the virus does not typically infect humans. Infections have occurred as a result of contact with infected birds. Spread of this infection from human to human has been reported to be extremely rare.

What Does Treatment For Influenza B Typically Involve


The treatments for influenza B and A are also pretty similar. You can use prescription meds to help shorten the duration of your illness, as well as other medication and lifestyle changes to lessen the intensity of your symptoms.

  • Antiviral medication: “These help to lower the duration of symptoms, and can help prevent serious complications,” says Dr. Shanker-Patel. There are currently 4 FDA-approved flu antivirals.
  • Over-the-counter fever reducers: “These are for fever control, and other symptoms,” says Dr. Shanker-Patel, and include nonsteroidal anti-inflammatory drugs like NSAIDs and acetaminophen .
  • Lots of rest and hydration
  • Staying home

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What Is Influenza Band How Is It Different Than Influenza A

Both influenza A and B are very contagious and have comparable rates of infection and death. But influenza A and B have some key differences that determine how prevalent they tend to be.

Influenza A: “Influenza A is a more common and faster-changing strain of influenza virus,” says Dr. Shanker-Patel, which is part of the reason it spreads so easily and tends to be the dominating strain during flu season, responsible for the majority of infections. Influenza A has subtypes, which are classified based on the combo of these two proteins found on the surface of the virus: hemagglutinin and neuraminidase . The two main circulating A subtypes in humans, says Dr. Shanker-Patel, are A and A.

Influenza B: Influenza B is normally less common and a more slowly changing strain of influenza. It gets classified under two lineages: B and B, says Dr. Shanker-Patel. With influenza B, people can be contagious days before the onset of symptoms, she notes.

Another difference between the two: B is found only in humans, while A can be found in other species like birds and pigs, according to Dr. Shanker-Patel.

Oh, and flu season usually involves strains of both flu types . For example, “The 2019-2020 influenza season in the northern hemisphere was predominately influenza B/Victoria and influenza Apdm09,” says Dr. Shanker-Patel.

Is The Flu Contagious

The flu is very contagious. People can spread it from a day before they feel sick until their symptoms are gone. This is about 1 week for adults, but it can be longer for young kids.

The flu usually happens in annual epidemics. An epidemic is when an illness spreads quickly and infects lots of people in an area at the same time. Some years the epidemic is more severe and widespread than others. An epidemic that spreads worldwide is called a pandemic. This is far less common. There were three influenza pandemics in the 20th century, and one so far in the 21st century, in 2009 with influenza A .

During the coronavirus pandemic, experts found that wearing masks can help protect the community from the spread of germs. They recommended that all children age 2 and up wear a mask when out in public or around people who don’t live with them. Wearing masks can also help stop the spread of flu.

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Treatment Of Bacterial And Viral Infections

Bacterial infections are most often treated with antibiotics, which are medications that prevent bacterial growth or kill them. Antibiotics do not work on viral infections.

Self-care such as getting enough rest and fluids and using over-the-counter medications for symptoms may be appropriate in mild cases of the common cold and flu.

People who are at high risk for complications from influenza may be treated by their healthcare provider with antiviral drugs.

Severe respiratory infections may require more extensive treatment, which could include hospitalization.

Antigenic Drift And Shift

Increase of influenza B seen with this year’s flu outbreak

Two key processes that influenza viruses evolve through are antigenic drift and antigenic shift. Antigenic drift is when an influenza virus’s antigens change due to the gradual accumulation of mutations in the antigen’s gene. This can occur in response to evolutionary pressure exerted by the host immune response. Antigenic drift is especially common for the HA protein, in which just a few amino acid changes in the head region can constitute antigenic drift. The result is the production of novel strains that can evade pre-existing antibody-mediated immunity. Antigenic drift occurs in all influenza species but is slower in B than A and slowest in C and D. Antigenic drift is a major cause of seasonal influenza, and requires that flu vaccines be updated annually. HA is the main component of inactivated vaccines, so surveillance monitors antigenic drift of this antigen among circulating strains. Antigenic evolution of influenza viruses of humans appears to be faster than influenza viruses in swine and equines. In wild birds, within-subtype antigenic variation appears to be limited but has been observed in poultry.

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Wall Street Reacts To Covid

One of the main circulating influenza viruses has changed and the current flu vaccines don’t match it well any more — an indication they may not do much to prevent infection, researchers reported Thursday. But they are still likely to prevent severe illness.

Common Bacterial Infections And Their Symptoms

The severity of bacterial infections can vary widely and depends on the type of bacteria involved. Some illnesses can be minor, but some can be more severe. Common respiratory bacterial infections and their symptoms include:

  • Strep throat: Streptococcus pyogenes can be spread from person to person by coughing, sneezing, and coming into contact with contaminated objects. It causes a sore throat and fever.
  • Bacterial pneumonia: Streptococcus pneumoniae is the classic bacteria causing pneumonia , although other bacteria may also be the cause. Symptoms include cough, high fever, chills, chest pain, and difficulty breathing. Bacterial pneumonia can develop after a viral upper respiratory tract infection.
  • Tuberculosis: Mycobacterium tuberculosis can infect the lungs and can spread to the kidney, brain, and spine. Symptoms include a bad cough that lasts three weeks or longer, coughing up blood, fever, weakness, weight loss, and night sweats.

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Which Children Are At Risk For The Flu

A child is more at risk for the flu if he or she:

  • Is around people infected with the flu

  • Has not had the flu vaccine

  • Does not wash his or her hands after touching infected surfaces

Young children and children with certain underlying health conditions are at increased risk for a hospital stay or severe or complicated influenza infection.

Understanding The Differences Between Bacterial And Viral Infections

Influenza Type B Virus and Tamiflu

Influenza is a contagious respiratory disease caused by the influenza A, B, or C virus. Influenza viruses are airborne and affect the nose, throat, and lungs.

Not all illnesses are caused by viruses. Some such as bacterial pneumonia can cause flu-like symptoms but are caused by bacteria. However, the flu can lead to bacterial infections as a person’s natural defenses may be weakened during an infection.

Infections that occur shortly after the primary infection are called secondary infections. In this article, we will cover the differences between bacterial and viral infections.

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Common Viral Infections And Their Symptoms

The severity of viral infections can also vary widely and depends on the type of virus involved. Common viral respiratory infections and their symptoms include:

  • The common cold:Typically caused by rhinoviruses and some coronaviruses. The common cold is usually mild and can include coughing, sore throat, sneezing, runny and stuffy nose.
  • Influenza :The flu is commonly caused by type A and B influenza strains. Symptoms are typically more severe than the common cold and can include coughing, fever , muscle aches, shortness of breath, and more.
  • COVID-19: Caused by the SARS-CoV-2 virus, symptoms include fever, dry cough, sore throat, runny nose, shortness of breath, loss of sense of smell and taste, fatigue, and more.
  • Viral pneumonia: This viral lung infection can be caused by viruses including coronaviruses, adenoviruses, influenza virus, parainfluenza virus, varicella-zoster virus, and respiratory syncytial virus . Symptoms include cough, difficulty breathing, increased breathing rate, and fever.

What Problems Can Happen

Some children are more likely to have problems when they get the flu, including:

  • kids up to age 5, especially babies
  • people with a weak immune system from medicines or illnesses or illnesses
  • people with chronic medical conditions, such as asthma or diabetes
  • kids or teens who take aspirin regularly
  • people who are very obese
  • women who are pregnant, trying to get pregnant, just had a baby, or are breastfeeding
  • people who live in long-term care facilities, such as nursing homes
  • people 65 years and older

If they get the flu, their illness can be more serious. They can develop pneumonia or get even sicker from other kinds of infections . If this happens, many will need medical care in the hospital. So it’s important for them not to be near anyone who has the flu or flu-like symptoms.

People who have flu symptoms should keep their distance from anyone who might get very sick if they catch the flu.

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Should I Worry About Catching Bird Flu

People in the United States have less to fear than people who live abroad. Most of the illnesses associated with bird flu have been reported in Asian countries among people who have had close contact with farm birds. Also, people are not able to catch the bird flu virus by eating cooked chicken, turkey, or duck. High temperatures kill the virus.

How Is The Flu Treated

CDC: Flu activity down, B strain virus is up

Most kids with flu get better at home. Make sure your child:

  • drinks lots of liquids to prevent dehydration
  • gets plenty of sleep and takes it easy
  • takes acetaminophen or ibuprofen to relieve fever and aches. Don’t give kids or teens aspirin because of its link to Reye syndrome.
  • wears layers that are easy to remove. Kids might feel cold one minute and hot the next.

Children with the flu should stay home from school and childcare until they feel better. They should go back only when they haven’t had a fever for at least 24 hours without using a fever-reducing medicine. Some kids need to stay home longer. Ask the doctor what’s best for your child.

Doctors may prescribe antiviral medicine for a very ill child or kids are at risk for more serious symptoms. The medicine can shorten the flu by 12 days. It works best if children start taking it within 48 hours of the start of the flu. If a doctor prescribes antiviral medicine for your child, ask about any possible side effects. Doctors won’t prescribe antibiotics for the flu. Antibiotics work only against bacteria, not viruses.

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Lesson #: Flu Strain Basics

Okay, we know we’re not all biology majors, so we’re going to take this slow and start from the very beginning. One of the most important things for you to know is that there are four types of influenza viruses: A, B, C, and D. Influenza A and B viruses are the ones we know really well in fact, they’re the ones that cause those almost-annual seasonal epidemics in the United States. Influenza C typically causes a mild respiratory illness and doesn’t typically cause epidemics. Finally, influenza D mostly affects cattle and, at least for now, is not known to infect people. Anyway, more on the specifics strains later.

The second most important thing for you to understand is how these viruses get their names. Influenza A viruses are all characterized based on two proteins on the outer shell of the virus: hemagglutinin and neuraminidase . Say those names ten times fast! These proteins both must be present in order for the virus to replicate, or reproduce. Hemagglutinin helps the virus attach to the cells in your body, and neuraminidase allows the virus to be released from the host cell once it has replicated ultimately spreading the infection.

Phew still with us? Okay, good.

What about those numbers, you ask? Well, they’re determined by the subtype, or secondary type, of hemagglutinin and neuraminidase proteins currently, there are 18 known hemagglutinin subtypes and 11 known neuraminidase subtypes , according to the CDC.2

Definition Of Exclusion Criteria

For influenza virus infections, the general exclusion criteria for febrile infections apply pursuant to the haemotherapy guidelines .

Special Precautions to Be Observed during the Pandemic Period

A risk/benefit analysis could be considered between a breakdown of blood supply and an emergency relaxation of the following donor selection criteria, in close coordination with the competent authorities:

  • reduce haemoglobin requirement of 13.5 to 13 g/l for men and from 12.5 to 12 g/l for women ,
  • increase donation frequency for platelet apheresis,
  • increase age limit for multiple donors to approximately 70 years ,
  • acceptance of donors already 1 week after recovery from influenza if subjective physical well-being has been restored ,
  • influenza prophylaxis using medicinal products is not an exclusion criterion, if no clinical symptoms have appeared.

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Lesson #: Influenza A Symptoms

Now that you’re ready to ace your next biology exam on flu virus nomenclature , we’re going to jump into Lesson #2: Influenza A.

Influenza A is typically responsible for those seasonal influenza epidemics that come around almost every winter. In the US, cases of seasonal flu typically spike during a few specific months of the year starting in September or October and running all the way through March or April This strain of the flu is also typically the most serious, and often has more severe symptoms than other strains, including coughing, sneezing, sore throat, fever, exhaustion, and chills and body aches.

This strain of the flu is most commonly found in humans and animals. In fact, remember that swine flu pandemic we were talking about at the beginning of this blog? Well, that virus is technically an influenza A virus, but it’s a little bit more complicated than that. That particular strain was so severe because it was a combination of swine, human, and bird flu viruses talk about a triple threat! The strain mutated so that it was no longer the same influenza A virus that our bodies are protected by through the annual flu vaccine.

Flu Mutation? Did You Really Just Say That?

Antigenic shift on the other hand is a you guessed it big ole’ shift, or change, to influenza A viruses. Such a big change, in fact, that it results in new hemagglutinin or neuraminidase proteins, meaning that the very subtype of the virus has changed completely.

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