Online Nursing Continuing Education

Influenza: Seasonal Flu 2014-2015
Symptoms, Treatment, and Prevention




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Influenza: Seasonal Flu 2014–15
Symptoms, Treatment, and Prevention

COURSE OBJECTIVE:  The purpose of this course is to prepare healthcare providers to educate patients and the general public, using evidence-based, up-to-date information about the symptoms, treatment, and prevention of seasonal influenza.


Upon completion of this course, you will be able to:

  • Discuss key concepts related to the transmission, symptoms, diagnosis, and treatment of influenza (flu).
  • Explain the rationale for vaccination and other preventative measures against seasonal flu, based on the chain of infection.


Influenza is an ancient and deadly disease, first described by Hippocrates more than 2,400 years ago. Since then, the disease has sickened and killed millions of people in local epidemics and global pandemics. The most lethal pandemic of record began in 1918, just after World War I, when 40 to 100 million people died from what was called the Spanish flu.

In 1931, Richard Schope discovered the cause of influenza (the Orthomyxoviridae family of viruses) in pigs; and in 1944, Thomas Francis Jr. developed the first significant steps toward preventing the disease with an inactivated-virus vaccine. His work was made practical by Frank MacFarlane Burnet, who showed that the virus lost virulence when it was cultured in fertilized hens’ eggs. This allowed researchers at the University of Michigan to develop the first influenza vaccine. Since then, vaccination has limited its spread but has not prevented pandemics of the disease (Potter, 2001).

In 1957, the Asian flu swept around the world, killing 1 to 1.5 million people, and in 1968, a pandemic called Hong Kong flu killed nearly a million more. Then, in 2009, a pandemic called swine flu, caused by virus found in pigs, swept around the world. As a consequence, a vaccine against the three causative viruses was developed. However, because viruses change constantly, each year WHO publishes vaccine recommendations to prevent what is now called seasonal influenza (CDC, 2014a; WHO, 2014).


All influenza viruses belong to the Orthomyxoviridae family of RNA virus, including types A, B, C, Isa virus, thogotovirus, and others. Each type contains two surface glycoprotein antigens, called subtypes hemagglutinin (HA) and neuraminidase (NA). The HA antigen enables the virus to enter cells, while the NA antigen facilitates cell-to-cell transmission. These subtypes are further differentiated by their numbered surface antigens, serotypes 1 to 10.


Type A viruses are the most virulent of influenza types, producing the most severe symptoms. They infect humans, other mammals, and birds and are the cause of all known pandemics, including:

  • H1N1: Spanish flu of 1918 and pandemic threat of 2009
  • H2N2: Asian flu of 1957
  • H3N2: Hong Kong flu of 1968
  • H5N1: pandemic threat of 2008

Type B viruses have only one serotype and infect humans and seals.

Type C viruses have one serotype, infect humans and pigs, and are relatively uncommon.

Isa virus infects fish and causes infectious anemia in salmon.

Thogotovirus is found in ticks, mosquitoes, and mammals; human epidemics from them are unknown.

Additional types of influenza viruses are being discovered, but to date, type A and B are known to pose the greatest threat to human health.


A number of human cases of “swine flu” f(H3N2v) have been reported in the United States beginning in August 2011. This virus normally occurs in pigs but does not usually infect people. Evidence from the 2011 and 2012 flu seasons suggests the strain produces mild symptoms and is judged to pose a relatively low risk of pandemic. Although the virus can be spread from human to human, it is primarily a zoonotic transmission (from animal to human). Most cases were contracted at fairs after exposure to pigs, and the CDC therefore recommends that children who are at high risk should avoid fairs where they may be exposed to pigs.

Early steps to make a vaccine against H3N2 have been taken, but there is no plan to mass-produce the vaccine at this time. (Seasonal flu vaccine is not designed to protect against H3N2v.) Public health authorities are watching this situation closely. They advise those who are in contact with pigs to take normal precautions such as washing hands frequently with soap and running water before and after exposure to animals and avoiding drinking, eating, or putting things in one’s mouth while in animal areas.

Source: CDC, 2014b.

Immune Response and Influenza Vaccines

When viruses laden with antigens infect a human or an animal, the body recognizes them as foreign substances and reacts in what is called an immune response. This response creates antibodies against the foreign substance. After recovery from the infection, the human or animal is usually immune to getting the same viral disease for years (perhaps a lifetime). Influenza vaccines help develop immunity by imitating an infection and causing the immune response that protects against the virus in the future (CDC, 2013).

Due to their immature immune response systems, children 6 months to 8 years old who are receiving an influenza vaccine for the first time require an additional dose. An optimal immune response will be initiated by administering a second dose a minimum of four weeks after the first dose. Because the strains contained in the 2014–15 seasonal influenza vaccines are identical to those contained in the 2013–14 vaccines, only one dose is required for any child aged 6 months through 8 years who previously received one or more doses during the 2013–14 flu season (CDC, 2014c).

Late in life, the immune systems become less responsive. In answer to this, a high-dose trivalent influenza vaccine has been developed for those 65 and over; it has been shown to induce significantly higher antibody responses and provide better protection against influenza illness. Progress is being made in the development of a high-dose vaccine for use in those under age 65 (DiazGranados et al., 2014).

Antigen Drift and Shift

Influenza viruses change constantly. They do this in two ways: antigenic drift and antigenic shift.

Antigenic drift is caused by an accumulation of the many small mutations that are continually occurring in both influenza A and B viruses. These mutations occur within both HA and NA genes. When this happens, antibodies may only partially recognize the resultant viruses or may not recognize them at all. Thus, when an antigen drift occurs, the current vaccine may not provide protection against disease. This is the reason why influenza vaccines must be updated annually.

Antigenic shift is an abrupt, major change in the influenza viruses, resulting in new HA and/or NA proteins. As a result, a new vaccine must be made to combat the altered virus. For this reason, people must be vaccinated anew to be protected from the altered virus of seasonal influenza (CDC, 2014d).

  • Small, incremental build up of changes
  • Large, sudden change
  • Expected, researchers alert to potential
  • Unexpected and unpredictable
  • Less likely to lead to pandemic
  • More likely to lead to pandemic


The most common way influenza viruses spread from person to person is by droplet infection. Infected people exhale, cough, or sneeze, and virus-containing droplets fly through the air into the nose and throat of others or onto some intermediate surface such as a doorknob. When other people touch a contaminated surface, viruses may stick to their fingers. When they touch the mucus membranes of their body, they inoculate themselves with the virus.

To prevent the spread of disease, individuals are instructed to:

  • Cover their nose and mouth with tissue when coughing or sneezing; discard tissues in the trash
  • Wash their hands often with soap and water or alcohol-based hand rub
  • Avoid touching their eyes, nose, and mouth
  • Avoid close contact with sick people
  • If sick with flu-like illness, stay at home for at least 24 hours after their fever is gone, except for medical care or for other necessities
  • While sick, limit contact with others as much as possible to keep from infecting them
  • Take flu antiviral drugs if prescribed by their primary care provider
    (CDC, 2014e)

There is limited evidence, but no proof, that face masks offer some protection against influenza. However, it is recommended that for those who must come into close contact with a sick person (within 6 feet), a mask may provide protection. Those with the flu may wear a mask when near other people and if they must leave home. In areas where influenza is widespread, uninfected individuals may wish to wear a face mask in crowded settings (DeNoon, 2014).

According to the CDC, sick adults are able to infect others beginning 1 day before symptoms appear and up to 5 to 7 days after they become ill. Sick children may be able to infect others beginning 1 day before symptoms appear and for more than 7 days after they become ill.

Symptoms develop 1 to 4 days after the virus enters the body. That means people may be able to pass on the flu virus to others even before they know they are sick. Any individual who is infected with viruses can infect others whether they show symptoms or not (CDC, 2014f).


John Smith, a 57-year-old man with a history of asthma, had been experiencing flu-like symptoms for three days. He was running a fever and, despite using his inhaler more frequently, finding himself increasingly short of breath. At the urging of his wife, he went to the emergency department (ED) to be checked.

The ED intake staff noticed that Mr. Smith was frequently coughing, so they responded per facility policy by offering him a facemask to wear while he sat in the waiting room. A few minutes later he was brought into triage, where the nurse confirmed that his symptoms were consistent with a contagious phase of influenza. During triage, the nurse allowed Mr. Smith to remove his facemask for his comfort but donned a facemask herself to minimize the risk that she might transmit the virus to her family or other patients who had not yet been vaccinated. During further diagnostic testing, the ED team continued the practice established by the triage nurse of wearing facemasks when they were within three feet of the patient while allowing him the comfort of not wearing a facemask.

Mr. Smith was admitted to the hospital with a diagnosis of left lower lobe pneumonia. On the advice of the infection prevention nurse, he was presumed to be infectious and was asked to wear a facemask when out of his room or being transported, while healthcare workers and visitors donned facemasks when they expected to come within three feet of him.

The infection prevention nurse explained to Mr. Smith and his family that, although there is no definitive evidence that facemasks decrease the spread of the influenza virus, it is still recommended to use facemasks as a prudent measure to decrease the spread of the virus.


Anyone can be infected with the flu virus, but the disease is more severe and the consequences more critical for some people than others. The most vulnerable are children under 5 years of age, especially those younger than 2 years of age; adults 65 years of age and older; pregnant women; and American Indians and Alaskan Natives (CDC, 2014g).

In addition, influenza can make chronic health problems worse. For example, individuals with asthma may suffer asthma attacks, and people with chronic congestive heart failure may experience an accumulation of fluid in the lungs, abdominal organs, and peripheral tissue. Generally speaking, people with the following medical conditions are more vulnerable to serious influenza-related complications:

  • Asthma
  • Neurological and neurodevelopmental conditions, including disorders of the brain, spinal cord, peripheral nerve, and muscles
  • Chronic lung diseases such as chronic obstructive pulmonary disease and cystic fibrosis
  • Heart diseases such as congestive heart failure, congenital heart disease, and coronary artery disease
  • Blood disorders such as sickle cell disease
  • Endocrine disorders such as diabetes
  • Metabolic disorders such as inherited metabolic and mitochondrial disorders
  • Weakened immune system due to disease or medication (such as HIV or AIDS, or those on chronic steroids)
  • Kidney disorders
  • Liver disorders
  • Morbid obesity (body mass index >40)
  • Any condition in children younger than 19 years of age that requires long-term aspirin therapy
    (CDC, 2014g)


Symptoms and Severity

Influenza is a highly contagious infection of the respiratory tract. It can cause mild to severe illness and may lead to death. The incubation period is brief and the onset sudden, causing chills, fever, aching muscles, and general malaise. Symptoms include:

  • Fever (usually high, however, not everyone with the flu has a fever)
  • Cough
  • Sore throat
  • Runny or stuffy nose
  • Muscle or body aches
  • Headache
  • Fatigue
  • Vomiting and diarrhea (in some people; more common in children than adults)
  • Tachycardia
  • Watery eyes
    (Derlet, 2014)

The indicators of influenza are referred to as “flu-like symptoms.” In the early stages of an infection, it may be difficult to distinguish between a common cold and influenza. However, the symptoms of flu are more severe and last longer than the common cold. A comparison of the usual symptoms of influenza and the common cold are listed below.

Symptom Influenza Common Cold
Source: Nazario, 2013.
Fever Characteristic, high (100 °F–102 °F), lasts three to four days Rare in adults and older children; may rise to 102 °F in infants and young children
Headache Sudden onset, may be severe Rare
Muscle aches Usual, often severe Mild
Fatigue Often extreme, may last 2 to 3 weeks Quite mild
Weakness Often extreme, may last 2 to 3 weeks; children may show low activity level Mild and, if present, of brief duration
Rhinitis and runny nose Common Common
Sneezing Common Common
Sore throat May occur Common
Nausea, vomiting, diarrhea May occur in adults; more common in children Never in adults
Cough Hacking; may be severe and last for weeks after infection Mild to moderate hacking cough


Diagnosis of influenza is based on presenting symptoms and viral tests. However, most individuals with flu symptoms do not require special testing because test results usually do not change their treatment. Individuals who have an acute febrile respiratory illness, sepsis-like syndrome, or are members of vulnerable groups listed above (such as infants, the elderly, and those with compromised immune systems) should be tested. This is because they require more intense treatment such as antiviral medications. Priority for diagnostic testing includes persons who 1) are at high risk for severe disease and 2) require hospitalization.


There are three types of tests that detect influenza viruses: rapid influenza diagnostic tests (RIDT), viral cultures (VC), and real-time RT-PCR. All require a mucus specimen collected from the back of the throat or nose by a healthcare provider (see “How to Obtain a Nasopharyngeal Specimen” below).

Rapid influenza diagnostic tests (RIDT) yield results in 15 minutes or less and display the results as “positive” or “negative.” However, these results are not foolproof and may give a false negative when the patient is actually infected or a false positive when the patient is not infected with influenza viruses. This test can help differentiate influenza from other viral and bacterial infections with similar symptoms. It is best used within 48 hours of symptom onset.

Viral culture (VC) of a mucus specimen is the “gold standard” for identifying which viruses and which strains of virus are present. However, traditional viral cultures can take up to 10 days for results. A faster culture method (shell vial culture) may detect the presence of a respiratory virus in 24 to 48 hours.

Reverse transcription-polymerase chain reaction (RT-PCR) is a molecular assay that can identify the presence of influenza viral RNA in respiratory secretions. It is increasingly being used in clinical settings and is most appropriate for hospitalized patients if a positive test would result in a change in clinical management. The test is used to detect newly emerging disease, such as new strains of flu (AACC, 2014).

  • Ask the patient to blow his or her nose just prior to specimen collection. Provide tissues and a place to dispose of the contaminated tissues. Then, the ask patient to wash or sanitize his or her hands with alcohol wipes.
  • Explain the procedure to the patient in order to obtain his or her cooperation.
  • Gather equipment: appropriate swab; transport media; and personal protective equipment (PPE), including gloves, gown, respiratory, and eye protection as prescribed by public health officials. Ideally, use a swab with a synthetic tip such as polyester or Dacron and an aluminum or plastic shaft. (Swabs with cotton tips and wooden shafts are not recommended, and those made of calcium alginate are not acceptable.) Specimen collection vials should contain 1 ml to 3 ml of viral transport medium containing protein stabilizer, antibiotics to discourage bacterial and fungal growth, and buffer solution.
  • Wash or sanitize your hands and put on PPE.
  • Instruct patient to tilt his or her head back.
  • Insert the swab straight back into one nostril; hold against the nasal septum until resistance is felt.
  • Rotate the swab for 15 seconds. Instruct the patient to swallow and not to cough.
  • Remove the swab and immediately place it into the collection vial. Label the specimen and send it to the laboratory for processing.
Illustration depicting technique for obtaining nasopharyngeal specimen.

Proper technique for obtaining a nasopharyngeal specimen. (Source: CDC, 2011.)

Source: Baden et al., 2009.


Comfort and Care

People young and old who are infected with the virulent viruses of flu are desperately ill. They sneeze and often have hacking coughs and runny noses. Their head and muscles ache, and they feel extreme fatigue. Nausea, vomiting, and diarrhea are common. Sick children and adults may crawl into a fetal position, shiver with chills and fever, and feel too sick to talk or even cry.

Such seriously ill people need rest, comfort, sleep, and extra fluids. They may benefit from analgesics and antipyretic medications such as ibuprofen (Advil) and acetaminophen (Tylenol). In spite of the misery for the first few days, most children and adults gradually recover in one to two weeks without complications or antiviral medications.

Because aspirin has been linked with Reye’s syndrome, children and adolescents under 18 years of age who are recovering from chickenpox or flu-like symptoms should not receive salicylates such as acetylsalicylic acid (aspirin) (Mayo Clinic, 2014). Aspirin should also be avoided due to its anticoagulant effects.

Antiviral Medications

Antiviral medications can shorten the duration of fever and illness, reduce the risk of complications from influenza, and shorten duration of hospitalization. The CDC (2014h) recommends these drugs be given as early as possible to individuals who exhibit more critical symptoms and suffer from chronic conditions or influenza-related complications such as:

  • Hospitalized patients with confirmed or suspected influenza
  • Individuals who are younger than 19 years of age who are receiving long-term aspirin therapy
  • People who are at higher risk for complications, including:
    • Children younger than 2 years of age
    • Adults 65 years and older
    • Women who are pregnant or postpartum within 2 weeks of delivery
    • People with certain chronic medical conditions
    • People with immunosuppression caused by medications, HIV, or other disorders
  • American Indians/Alaska Natives
  • Persons who are morbidly obese (body mass index >40)

Antiviral drugs are recommended to treat children with severe, complicated, or progressive illness, or who are hospitalized with confirmed or suspected influenza, as well as children at higher risk of flu-related complications with influenza infection of any severity. Children at high risk for complications are those younger than 5 years and children of any age with chronic health conditions such as asthma, diabetes, heart disease, or lung disease (CDC, 2014i).

Drugs recommended by the CDC to fight type A and B influenza are:

  • Oseltamivir (Tamiflu): Available as a liquid or capsule, oseltamivir is approved both to prevent and treat flu in people of any age. The most common side effects are nausea and vomiting. The U.S. Food and Drug Administration requires that the package warn that people with the flu, especially children, may be at an increased risk of confusion and self-injury after taking the drug. Therefore, recipients should be monitored closely for signs of unusual behavior.
  • Zanamivir (Relenza): Available only as a powder, zanamivir is administered to the respiratory tract via an oral disk inhaler device. It is approved to treat flu in people 7 years of age and older. The most common side effects are diarrhea, nausea, sinusitis, bronchitis, cough, headache, dizziness, and ear, nose, and throat infections. It is contraindicated for those with underlying respiratory disease such as asthma or COPD.

Both antiviral drugs work best when started within two days of the onset of symptoms (without waiting for laboratory confirmation of the disease) and continued for at least five days. Hospitalized patients may benefit from treatment even if the drug is started more than 48 hours after symptoms begin and treatment is continued for a minimum of five days (CDC, 2014j).


The Chain of Infection and Prevention of Seasonal Influenza

The process of transmission of an infectious agent such as the influenza virus can be best explained by the epidemiologic model called the chain of infection. An infectious disease results from specific interactions between the organism, host, and environment. Transmission occurs when the infectious organism leaves the reservoir or host through a portal of exit, travels by some mode of transmission, and enters through a portal of entry to infect another susceptible host (CDC, 2012).

Chain of infection.

Chain of infection. (Source: Wild Iris Medical Education.)

  • A reservoir of an infectious agent is the habitat where the agent normally lives and grows. Reservoirs may be humans, animals, or the environment.
  • The portal of exit is the path by which the infectious agent leaves its host (e.g., sneezing).
  • Means of transmission is the mode in which the infectious agent is transmitted from its natural reservoir to a susceptible host (e.g., touching a doorknob that contains infectious particles). Transmission can occur in a mode that is direct or indirect.
  • The portal of entry refers to the way in which the infectious agent enters the host (e.g., through one’s nose when breathing in airborne particles). The portal of entry must provide access to tissues in a way that allows the infectious agent to multiply and thrive.
  • The final link is the vulnerable host. Susceptibility of a host depends on many factors, including immunity and the individual’s ability to resist infection (CDC, 2012).

By breaking any link of the chain of infection, healthcare professionals can prevent the occurrence of new infection. Infection prevention measures are designed to break the links and thereby prevent new infections. The chain of infection is the foundation of infection prevention.

Link Influenza Implications Healthcare Provider Actions
Organism Present in environment during flu season Be aware of current strains and case reporting requirements
Reservoir Potentially everyone, some higher risk Promote vaccinations
Portal of Exit Airborne particles Teach/reinforce sneeze/cough etiquette and correct use/disposal of tissues
Transmission Organism can remain active on environmental surfaces Teach disinfection techniques
Portal of Entry Nose/mouth Teach/reinforce handwashing, not touching eyes/face, wearing masks
Vulnerable Hosts Everyone; some people at greater risk Promote vaccinations among high-risk groups

Because influenza produces such serious symptoms, the CDC issues prevention recommendations to the public.

  1. Take time to get flu vaccinations.
  2. Take everyday preventative actions:
    • When coughing or sneezing, cover the nose and mouth with the arm or with a tissue, then discard tissues in the trash.
    • Wash hands often with soap and water or use alcohol-based rub.
    • Avoid touching the eyes, nose, and mouth.
    • Stay at home for at least 24 hours after the fever is gone except to get medical care or necessities.
    • When it is necessary to go out, limit contact with others, especially avoiding nasopharyngeal droplets from infected individuals.
  3. Take flu antiviral drugs if recommended by a doctor.

Source: CDC, 2014a.

Routine cleaning and disinfection strategies can also help prevent the spread of influenza. Management of laundry, utensils, and medical waste should be performed in accordance with established procedures.

Who Should Be Vaccinated?

Everyone 6 months of age and older should get vaccinated against the flu except for a few select individuals (see below). Vaccination is especially important for vulnerable individuals with chronic medical conditions, healthcare workers, and others who live with or care for high-risk people. Those who care for children younger than 6 months should be vaccinated (CDC, 2014a).


Those who should not be vaccinated before talking to their doctor include:

  • Those who have had a severe reaction to an influenza vaccination in the past (pain, swelling, and redness at the site of injection are not considered severe; any other symptoms should be reported to a physician prior to administration)
  • Persons with moderate to severe acute febrile illness until symptoms are relieved
  • Those who developed Guillain-Barré syndrome within six weeks of getting an influenza vaccine previously

CDC guidelines should be carefully reviewed on a case-by-case basis with a physician before administering a vaccine to a person with a history of egg allergy (CDC, 2014k). In the past, people with egg allergies were unable to receive the vaccine. Current guidelines include:

  • For those with severe egg allergies, a new “egg-free” vaccine is now available in limited quantities.
  • Those with mild egg allergies can be vaccinated but should not receive a live attenuated vaccine.
  • For those with mild or severe egg allergies, the vaccine should only be administered in settings with emergency equipment and a physician with experience in managing anaphylaxis present.

Since 1981 the CDC has recommended healthcare workers receive influenza vaccination, and the coverage among healthcare workers during the 2013–14 season was 75.2%. Coverage was highest (97.8%) among healthcare personnel working in settings in which flu vaccination was a requirement for employment (CDC, 2014).

The Affordable Care Act includes mandates for flu vaccinations of healthcare workers. Failure to meet certain percentages of a healthcare facility’s employees vaccinated for influenza will jeopardize federal reimbursement of Medicare and Medicaid funds beginning in 2015. The goal is to have 90% compliance for healthcare workers by 2020 (DHHS, 2011).

While it is obvious that recommending and increasing influenza vaccination in healthcare workers is important, it is less obvious how best to achieve this goal. During 2013 there was an increase in the number of healthcare facilities mandating nurses and other healthcare workers to receive flu vaccinations as a condition of employment.

There is great controversy, however, over the issue of mandatory vaccination, with strong arguments for differing points of view regarding individual rights versus the right of patients to be protected from disease transmitted by a healthcare worker.

Vaccines for the 2014–15 Influenza Season

Influenza vaccines are updated annually to provide a combination of the most likely flu strains to be in circulation. There are several flu vaccine options for the 2014–15 season. Traditional flu vaccines made to protect against three different flu viruses (trivalent) are available. Additionally, flu vaccines made to protect against four different flu viruses (quadrivalent) are available.

Trivalent vaccine protects against two influenza A viruses (H1N1 and H3N2) and one influenza B virus. The trivalent flu vaccine available for the 2014–15 flu season is made from the same three viruses as the 2013–14 vaccine:

  • A/California/7/2009 (H1N1) pdm09-like virus
  • A(H3N2) virus antigenically like the cell-propagated prototype virus NA/Victoria/361/2011
  • B/Massachusetts/2/2012-like virus

This year’s quadrivalent vaccine contains the above three strains plus a B/Brisbane/60/2008-like virus (CDC, 2013l).


The U.S. Food and Drug Administration has licensed the following seasonal flu vaccines for use in the United States in 2014–15 (CDC, 2014l):

  • Inactivated influenza vaccine, trivalent (IIV3), standard-dose: An inactive virus grown in eggs, approved for persons age 6 months and older, and given intramuscularly in the arm (IIV3 intradermal injection also available)
  • Inactivated influenza vaccine, trivalent (IIV3), high-dose: Approved for people age 65 and older
  • Inactivated influenza vaccine, trivalent, standard dose, cell cultured-based (ccIIV3): Vaccine-grown in animal cells, approved for people 18 years and older
  • Recombinant influenza vaccine, trivalent (RIV3): A vaccine that does not use the influenza virus or chicken eggs in its manufacturing process, approved for people 18 to 49 years of age
  • Inactivated influenza vaccine, quadrivalent (IIV4), standard-dose: Approved for children 3 years and younger
  • Live attenuated influenza vaccine, quadrivalent (LAIVe) nasal spray: Protects against four flu viruses (two A influenza viruses and two B viruses); now recommended instead of the flu shot for use in all healthy children 2 to 8 years of age when available; nasal spray contraindicated in children younger than 2 years, adults 50 and older, and pregnant women
    (CDC, 2014m)

The increasing number of vaccination dosing and route options is leading to improved targeting and specificity in delivering influenza immunization while also allowing more people to be vaccinated than ever before. However, the variety of options is beyond what providers can commit to memory, particularly considering the frequency with which the options are updated.

Nurses who expect to be providing influenza vaccines should familiarize themselves with the CDC references and obtain copies of the most current vaccine dosing and administration tables so, in consultation with medical providers, they are prepared to quickly ascertain the best vaccine options for their patients (see “Resources” at the end of this course).


On a Friday in early September, a female patient asked Maria Jones, RN, when she should receive her annual flu shot and if she could have the nasal spray so she didn’t need to have “a shot.” Maria was embarrassed because she was unprepared to answer the question. She told the patient she wasn’t sure but thought it was still a little early and reassured the patient that she would look into it and give her a call with further information.

Over the weekend, Maria went to the CDC website and read about seasonal influenza vaccinations. She found a table that showed dosing and route information as well as information regarding when vaccinations should be provided. She printed the table and presented it to her nurse and physician coworkers when she came to work Monday morning. Together, they practiced using the tables to determine the best option for a variety of their patients.

With a confirmation from the physician, Maria was then able to call her patient. She told the patient that the CDC recommends vaccines be given as soon as they are available and that the clinic expected to have their first doses available in early October. Maria informed her patient that, unfortunately, she was outside the age recommendations for the nasal spray and would need to get a shot.


A serious complication of influenza is pneumococcal pneumonia caused by Streptococcus pneumonia. It is the leading cause of vaccine-preventable illness and death in the United States. Adults 65 years and older are at greater risk for contracting this disease. Also, because some strains of this bacterium have become resistant to drugs that were effective in the past, prevention through vaccination has become even more important.

The best prevention of pneumococcal pneumonia is by vaccination with both the influenza and pneumococcal vaccines. It is recommended that:

  • Adults age 65 or older who have never received a pneumococcal vaccine or whose previous vaccination history is unknown should receive a dose of 13-valent pneumococcal conjugate vaccine (PCV13) if there is no medical reason not to administer it.
  • Adults over age 65 should receive a dose of 23-valent pneumococcal polysaccharide vaccine (PPSV23) 6 to 12 months after the PCV13 vaccination.
  • Adults age 65 or older who have not previously received the PCV13 vaccine but have received one or more doses of PPSV23 should receive a dose of PCV13 at least one year after the most recent dose of PPSV23.

Source: AAFP, 2014.

Public Education

Prevention of epidemics and pandemics depends on education of the public about the importance of vaccination and personal hygiene. The greater the number of vaccinated individuals, the fewer the cases of influenza. With increased prevention by individuals, such as covering a sneeze or cleansing the hands, the flu virus will be less likely to infect other people. For these reasons, healthcare providers have a special responsibility to encourage the general public to be vaccinated and to practice preventative measures.


Influenza continues to be a deadly disease, but due to the work of scientists and clinicians, people can be protected from infection by the ever-changing influenza viruses. With vaccination against the viruses and protective sanitary measures, infections can be reduced; and with antiviral medications, vulnerable individuals and those who are infected can be treated. Healthcare providers play an important role in delivering this message to those they serve.


NOTE: Complete URLs for references retrieved from online sources are provided in the PDF of this course (view/download PDF from the menu at the top of this page).

American Academy of Family Physicians. (2014). ACIP recommends routine PCV13 immunization for adults 65 and older. Retrieved from

American Association for Clinical Chemistry (AACC). (2014). Influenza tests. Retrieved from

Baden LR, Drazen JM, Kritek PA, Curfman GD, Morrissey S, & Campion EW. (2009). H1N1 influenza a disease—information for professionals. New England Journal of Medicine, 360(25), 2666–7.

Centers for Disease Control and Prevention (CDC). (2014a). What you should know for the 2014–2015 influenza season.  Retrieved from

Centers for Disease Control and Prevention (CDC). (2014b). Protect yourself against H3N2v. Retrieved from

Centers for Disease Control and Prevention (CDC). (2014c). Prevention and control of seasonal influenza with vaccines: recommendations of the Advisory Committee on Immunization Practices (ACIP)—United States, 2014–15 influenza season. Retrieved from

Centers for Disease Control and Prevention (CDC). (2014d). How the flu virus can change: “drift” and “shift.” Retrieved from

Centers for Disease Control and Prevention (CDC). (2014e). CDC says “Take 3” actions to fight the flu. Retrieved from

Centers for Disease Control and Prevention (CDC). (2014f). How flu spreads. Retrieved from

Centers for Disease Control and Prevention (CDC). (2014g). People at high risk of developing flu-related complications. Retrieved from

Centers for Disease Control and Prevention (CDC. (2014h). Influenza antiviral medications: summary for clinicians. Retrieved from

Centers for Disease Control and Prevention (CDC). (2014i). Children and antiviral drugs. Retrieved from

Centers for Disease Control and Prevention (CDC). (2014j). Influenza antiviral medications: summary for clinicians. Retrieved from

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