Introduction to Flu Vaccination
The flu vaccine, also known as the flu shot, is an annual vaccination recommended for nearly everyone over 6 months old to protect against influenza, a contagious respiratory illness that can cause fever, cough, sore throat, body aches, headaches, and other symptoms. Getting the flu vaccine is the best way to prevent getting sick with the flu and spreading it to others. It also reduces the risk of developing potentially serious flu complications like pneumonia, which could lead to hospitalization or death. This article provides a comprehensive overview of everything you need to know about the annual flu shot.
What is the Flu Vaccine?
The flu vaccine contains either a weakened or inactivated version of live influenza viruses. It stimulates your immune system to produce antibodies that provide protection against the strains of flu viruses the vaccine is designed for.
There are several different types of flu vaccines approved for use each flu season. Most are given via intramuscular injection, usually in the upper arm, but there are also options administered as a nasal spray. Flu shots contain either 3 strains (trivalent) or 4 strains (quadrivalent) to protect against the influenza A H3N2, H1N1, and influenza B viruses predicted to be most common that flu season.
Why Get a Flu Shot?
Here are some of the biggest benefits of getting an annual flu vaccination:
- Reduces your risk of catching the flu by 40-60%
- Makes your illness milder if you do get sick
- Lowers your chance of being hospitalized from flu complications
- Protects people around you, including infants and the elderly
- Saves healthcare costs from flu-related doctors’ visits and hospitalizations
- Avoids missing school or work due to illness
- Contributes to community immunity to reduce flu spread
Types of Flu Vaccines
There are several vaccine options approved for different ages:
- Trivalent/Quadrivalent: Protects against either 3 or 4 flu strains
- High-Dose: Higher antigen dose for older adults
- Adjuvanted: Contains adjuvant to boost immune response
- Cell-Based: Grown in cell culture instead of eggs
- Recombinant: Flu proteins made without flu viruses
- Nasal Spray: Live attenuated flu vaccine given as a nasal spray
Effectiveness of the Flu Vaccine
How well the flu vaccine works in protecting against influenza viruses can vary each year. Here’s an overview of flu shot effectiveness and what impacts it.
How Well Does the Flu Vaccine Work?
In years when the flu strains in the vaccine and circulating strains are well-matched, effectiveness of the flu shot against illness requiring medical care is typically around 40-60%. Some years it is lower when there is a mismatch, while other years it can be higher. Even when the vaccine doesn’t fully prevent flu illness, it often makes symptoms milder and prevents serious outcomes like hospitalization.
Factors Affecting Effectiveness
A few key factors play a role in flu shot effectiveness each season:
- Match to Circulating Strains: How closely the strains chosen match ones spreading
- Age: Lower initial immune response in seniors but still provides protection
- Health Status: Weaker immune systems reduce effectiveness for some
- Time Since Vaccination: Protection declines over the course of a flu season
Comparing Flu Shot Effectiveness Over Time
Flu vaccine effectiveness has ranged in recent seasons from around 40% to 60% overall. During the severe 2017-2018 flu season, effectiveness was estimated at just 38% overall, but was higher (40-60%) in children. Vaccine mismatch contributed to reduced protection. Effectiveness improved to around 47% and 45% for the 2018-2019 and 2019-2020 flu seasons. Early data suggests effectiveness for the initial strains during the 2020-2021 flu season was higher at around 62%.
Source: Vaccine Effectiveness
Who Should Get the Flu Vaccine?
The CDC recommends annual flu vaccination for nearly everyone over 6 months of age, with rare exceptions. Some groups have a higher risk of flu complications.
CDC Recommendations
The CDC recommends a yearly flu vaccine for:
- All persons over 6 months of age
- Pregnant women
- Adults over 50 years old
- Those with underlying medical conditions
- Residents of nursing homes or long-term care facilities
- Healthcare personnel
- Caregivers of high-risk individuals
- American Indians and Alaskan Natives
Benefits for High-Risk Groups
Flu vaccination is especially critical for those at increased risk of severe flu and complications, including:
- Adults over age 65
- Children under age 5
- Pregnant women
- Those with conditions like asthma, heart disease, diabetes, cancer, autoimmune disorders, kidney or liver disease, and HIV/AIDS
- Morbidly obese individuals
- Nursing home and long-term care facility residents
Flu Shot for Pregnant Women and Children
The flu vaccine is safe during pregnancy and offers protection for both the expectant mother and her baby for several months after birth. The CDC recommends flu shots for children starting at 6 months of age. Children under 9 getting their first flu vaccine require 2 doses given at least 4 weeks apart for best protection.
Optimal Timing for Flu Vaccination
Timing your annual flu shot correctly can optimize protection throughout flu season. Here’s guidance on when to get vaccinated.
When to Get a Flu Shot Each Season
Flu activity typically ramps up between December to February. Optimal timing for flu vaccination is usually late September through late October, although getting vaccinated later is still beneficial. Immunity develops around 2 weeks after getting the shot. Protection can last 6 months, but declines over time.
Before or During Flu Season
Getting vaccinated before flu viruses begin circulating widely offers the best defense. However, vaccination during peak flu season in January or later can still provide protection during that season. Being proactive is best since you want immunity already established before exposure to the flu.
Getting Vaccinated When Sick
It’s fine to get a flu shot when you have a mild illness without fever, but best to wait if you have a moderate or severe illness until symptoms improve. Vaccination is also recommended when you’ve been exposed to flu viruses, since it can still provide protection and reduce symptom severity.
Side Effects and Safety Concerns
The flu shot is very safe, but some mild side effects are possible. Serious adverse events are rare. Here’s information about what to expect and common flu vaccination misconceptions.
Common Side Effects
Typical side effects from the flu shot tend to be minor and resolve within days:
- Soreness, redness or swelling at injection site
- Low-grade fever
- Headache
- Muscle aches
- Fatigue
- Nausea
These reflect the normal immune response to vaccination. Nasal spray flu vaccines may cause nasal congestion, cough, sore throat or runny nose. Serious side effects are very uncommon.
Source: Do flu vaccines cause any side effects?
Serious Side Effects Are Rare
Severe allergic reactions (anaphylaxis) can rarely occur after any vaccination and may require emergency treatment. Extremely rare neurological side effects like Guillain-Barre Syndrome were linked to a flu vaccine in 1976 but not with flu shots since then. Injectable flu shots contain inactivated viruses and can’t cause flu illness.
Flu Shot Myths and Misconceptions
Here are some common flu vaccine myths along with the real facts:
- Myth: The flu shot gives you the flu.
- Fact: The flu vaccines cannot cause flu illness.
- Myth: Vaccines contain dangerous ingredients.
- Fact: Flu shot ingredients and vaccine safety are closely regulated.
- Myth: The flu vaccine is ineffective.
- Fact: Flu shot effectiveness varies but provides important protection.
- Myth: The flu isn’t serious.
- Fact: Flu brings a heavy burden of hospitalizations and deaths each year.
Where to Get Flu Shots
The flu vaccine is widely available at various locations throughout flu season. Both vaccine costs and eligibility for insurance coverage vary by location.
Doctor’s Office
One option for flu vaccination is through your primary care physician’s office. Many insurances cover the full cost of the vaccine when administered at an in-network medical provider. Your doctor can also review your medical history for any concerns about the flu shot.
Pharmacies
Local pharmacies like CVS, Walgreens, Rite Aid and grocery store pharmacies commonly offer flu shots, often at walk-in immunization clinics beginning in the fall through the winter. Vaccine costs may be covered by insurance or out-of-pocket.
Flu Shot Clinics
Pop-up flu shot clinics in the community can provide inexpensive or free vaccination options. Check your local health department, churches, schools, community centers or workplaces for availability. Many workplaces now offer annual on-site flu shot clinics to help prevent flu on the workplace and make vaccination convenient and accessible for employees.
Improving Future Flu Vaccines
While flu shots offer important protection, researchers are working to develop even more effective vaccines for the future.
Universal Flu Vaccine Research
Scientists are investigating game-changing “universal flu vaccines” that could provide long-lasting protection against all flu strains so repeat annual vaccination may not be needed. Research is ongoing.
Potential New Vaccine Options
New types of flu vaccines in development include skin patches, oral versions, use of adjuvants to boost immune response, and vaccines derived from cell-based cultures rather than eggs. These emerging options could change flu immunization in the future.
Flu Shot Recommendations May Evolve
Improved understanding of how previous flu exposures and new technologies impact immune response may lead to changes in optimal timing, use of booster doses, personalized vaccine approaches, and usage recommendations in certain populations.
Flu Prevention Beyond Vaccination
While getting an annual flu shot is the best defense, practicing additional healthy habits can also help stop the spread of flu.
Other Ways to Avoid the Flu
Recommended flu prevention strategies beyond vaccination include:
- Staying home when sick
- Covering coughs and sneezes
- Washing hands frequently
- Avoiding touching your face
- Cleaning high-touch surfaces
- Avoiding crowds when flu is widespread
Hand Washing, Masks, Distancing
Proper hand hygiene, wearing face masks around those ill, and physical distancing from those symptomatic can further limit person-to-person flu transmission.
Treatment if You Do Get Sick
Antiviral medication may be prescribed to treat flu illness and reduce severity. Staying hydrated and getting ample rest while sick with influenza is key.
Flu Vaccination FAQs
Here are answers to 6 of the most frequently asked questions about the annual flu vaccine:
Is the flu vaccine safe?
Yes, flu shots are very safe. Most side effects are mild like arm soreness. Serious adverse events are extremely rare.
Can you get the flu from the flu shot?
No, the vaccine cannot cause flu illness since shots contain killed viruses.
Are flu shots effective?
Flu vaccine effectiveness varies year to year, but typically provides 40-60% protection against influenza on average.
Who should not get a flu shot?
It’s recommended for nearly everyone over 6 months old, with very few exceptions. Always discuss your medical history with your doctor first.
Can you get a flu shot when pregnant?
Yes, the flu vaccine is safe and recommended during pregnancy to protect mom and baby.
Source: CDC Influenza (Flu) Vaccine and Pregnancy
When should you get a flu shot for the best protection?
Optimal timing is early fall before flu activity picks up, but later vaccination can still be beneficial.
Conclusion
The influenza vaccine is vitally important to protect yourself, loved ones, and community members from the flu each year. This guide provides you with helpful information on flu shot effectiveness, optimal timing, safety, recommendations for vaccination, and more. Talk to your doctor and make plans to get your annual flu vaccine – it can truly save lives! With Flu Vaccination, you can have peace of mind knowing you’ve taken action against the flu.
Read Also: 13 Office Flu Prevention Strategies to Keep Your Workplace Healthy
