Updated Recommendations for Flu Vaccination

As the calendar advances to the fall months, we are reminded everywhere that it’s time for the annual influenza vaccination. In August 2011, the Advisory Committee on Immunization Practices (ACIP) updated its vaccination recommendations to include new guidelines for children ages 6 months through 8 years, and for persons with egg allergy.

Here are some highlights from their report, published in the Centers for Disease Control and Prevention’s Morbidity and Mortality Weekly Report (Prevention and control of influenza with vaccines: recommendations from the Advisory Committee on Immunization Practices. MMWR. 2011;60:1128-1132. Also online at www.cdc.gov/mmwr/preview/mmwrhtml/mm6033a3.htm) 

Influenza strains: The 2011-2012 influenza virus strains remain unchanged from those in the 2010-2011 vaccine. The current “cocktail” contains A/California/7/2009 (H1N1)-, A/Perth/16/2009 (H3N2)-, and B/Brisbane/60/2008-like antigens.

Who should get vaccinated: Because vaccine efficacy and antibody titers both decline in the year following vaccination, the CDC recommends an annual flu shot for everybody 6 months and older. Ideally, patients should be vaccinated as soon in the year as vaccine becomes available.

Recommendations for children ages 6 months through 8 years:  For best response, children who are being immunized for the first time should receive 2 doses of vaccine, 4 or more weeks apart.

Previously, children in this age group who received a single dose of initial vaccine required 2 doses the next season. However, since the vaccine is unchanged from last year, children who have received at least a single dose of the 2010-2011 vaccine will only need 1 dose of the 2011-2012 preparation. If the child’s vaccination history is nil or unknown, plan to give the 2 doses of the 2011-2012 vaccine.

Recommendations for persons with egg allergy: Most vaccine manufacturers list egg allergy as a contraindication to vaccination. However, several studies show trivalent inactivated vaccine (TIV) to be safe in patients with egg allergy, and some TIV product package inserts list severe egg allergy (anaphylaxis) as the only contraindication to vaccination. Keep in mind that various commercial vaccine preparations vary with respect to the quantity of egg protein present. Up to 1.4 ug/mL (0.7 ug/0.5 mL dose) appears to be safe and well tolerated. Package inserts are not required to list the ovalbumin concentration of the vaccine; if in doubt, ask the manufacturer.

ACIP advises the following:
• For children and adults who are mildly allergic (reaction limited to hives) to eggs, give TIV, rather than live attenuated influenza vaccine (LAIV), preparations. The patient should be observed for 30 minutes after vaccination for signs of egg allergy.
• Children and adults with severe allergic reactions (angioedema, respiratory distress, emesis, etc) or who have required epinephrine after egg exposure and who are at risk for anaphylaxis should be referred to/evaluated by someone experienced in handling severe allergy, as a preliminary to vaccination. 
• The patient should receive the vaccine in an office equipped to handle anaphylaxis.
• Any history of anaphylaxis in response to the influenza vaccine contraindicates future vaccinations.

Available vaccines:
The Table summarizes the range of commercially available influenza vaccines to choose from.

Table. Flu vaccine choices

Trade name

Age group

Presentation

No. doses

Route

TIV

Fluzone

6-35 mo

0.25 mL prefilled syringe

1 or 2

IM

≥ 36 mo

0.5 mL prefilled syringe

1 or 2

IM

≥ 36 mo

0.5 mL vial

1 or 2

IM

≥ 6 mo

5.0 mL multidose vial

1 or 2

IM

TIV

Fluvirin

≥ 4 yr

0.5 mL prefilled syringe, 5.0 mL multidose vial

1 or 2

IM

TIV

Fluarix

≥ 3 yr

0.5 mL prefilled syringe

1 or 2

IM

TIV

FluLaval

≥ 18 yr

5.0 mL multidose vial

1

IM

TIV

Afluria

≥ 9 yr

5.0 mL multidose vial, 0.5 mL prefilled syringe

1

IM

TIV High-Dose

Fluzone High-Dose

≥ 65 yr

0.5 mL prefilled syringe

1

IM

TIV Intradermal

Fluzone Intradermal

18-64 yr

0.1 mL prefilled microinjection system

1

ID

LAIV

FluMist

2-49 yr

0.2 mL prefilled intranasal sprayer

1 or 2

IN

TIV, trivalent inactivated vaccine; LAIV, live attenuated influenza vaccine; IM, intramuscular; IN, intranasal; ID, intradermal.
Ovalbumin content of all listed vaccines is ≤ 1µg/0.5 mL dose.

For a Patient Education Guide, click here.

A Patient Education Guide

Questions and Answers about the Flu Vaccine

What’s in the flu vaccine?
The flu vaccine contains either inactivated or weakened strains of 3 influenza viruses. Flu vaccines that are given by nasal spray are made up of live, weakened flu viruses. The viruses in these so-called “live attenuated influenza vaccines” are not strong enough to make you sick, but they do trigger your body to make antibodies against the influenza virus. Flu vaccines that are given as a shot contain killed viruses and are known as trivalent inactivated vaccine.

Who should receive the flu shot?
Immunization is recommended every year for almost everyone 6 months of age and older, unless they have a condition that warns against it. Vaccination is especially important for:

Are there any reasons why I should not get vaccinated?
Talk with your doctor before getting a flu vaccine if you:

Who should get which kind of flu shot?
If you are 65 years and older, you can receive the high-dose flu shot. The flu shot is approved for people 18 to 64 years old. The nasal spray flu vaccine is an option for anyone between the ages of 2 and 49 years. Infants can receive the regular flu shot.

When should I get vaccinated?
Plan to get the vaccination as soon as it becomes available in your area. This is important because it takes about 2 weeks to build up enough antibodies to protect you against flu. Vaccinations are typically available between October and May, but the best time to get vaccinated is before December so that you are protected during peak flu season.

Will I get sick from the vaccine?
Depending on the type of vaccine you receive, you might experience different symptoms. If you receive a shot, you can expect some tenderness and swelling to develop at the vaccination site. You might also have fever and minor aches.  If you are vaccinated by nasal spray, you might experience runny nose, wheezing, headache, vomiting, sore throat, cough, and muscle aches.

All these symptoms are temporary and generally resolve within a day or two. Don’t panic, this is perfectly normal and does not mean that you have the flu! Quite the opposite: the symptoms are a sign that your body is building up protective antibodies to fight off a full-blown case of the flu.

(Source: Centers for Disease Control: Seasonal Influenza-Key Facts about Seasonal Flu. www. cdc.gov/flu/protect/keyfacts.htm)