What flu vaccine is recommended for patients of all ages, including those with chronic health conditions, pregnant women, and healthcare workers, in a specific location this year?

Influenza Vaccination Recommendations for Current Season

All persons aged ≥6 months without contraindications should receive annual influenza vaccination, with any licensed, age-appropriate vaccine formulation acceptable for use. 1

Universal Vaccination Policy

The CDC and American Academy of Pediatrics have established universal vaccination rather than risk-based targeting, representing a comprehensive population coverage approach. 1 This means vaccination is recommended regardless of health status, though certain populations require prioritized efforts.

Vaccine Selection by Age Group

Adults 18-64 Years (Not Pregnant or Immunocompromised)

• Use either standard-dose trivalent or standard-dose quadrivalent influenza vaccine (cell-based, egg-based, MF59-adjuvanted, or recombinant formulations are all acceptable). 2
• Any age-appropriate inactivated influenza vaccine (IIV) or recombinant influenza vaccine (RIV4) is suitable. 3

Adults ≥65 Years (Not Immunocompromised)

• Use either high-dose trivalent or high-dose quadrivalent egg-based influenza vaccine. 2
• The ACIP states that any age-appropriate inactivated influenza vaccine formulation is acceptable, including standard-dose, high-dose, adjuvanted, or recombinant vaccines. 4
• Vaccine effectiveness in this age group is 30-70% for preventing hospitalization and 80% effective in preventing death in nursing home residents. 4

Children 6 Months Through 8 Years

• Inactivated influenza vaccine (IIV) is preferred as the primary choice for all children. 1
• Children aged 6-35 months may receive FluLaval Quadrivalent at 0.5 mL per dose or Fluzone Quadrivalent at 0.25 mL per dose. 3
• Children <9 years receiving influenza vaccine for the first time require 2 doses separated by ≥4 weeks. 3

Children and Adolescents 5-18 Years

• Any age-appropriate IIV or RIV4 is suitable. 3
• Live attenuated influenza vaccine (LAIV) is NOT recommended due to low effectiveness against influenza A(H1N1)pdm09 in recent seasons. 3

Priority Populations Requiring Special Effort

High-Risk Medical Conditions

• All persons with chronic pulmonary diseases (including asthma), cardiovascular disease, renal disease, hepatic disease, neurologic disorders, hematologic disorders, or metabolic diseases (including diabetes mellitus). 3, 1
• Persons who are immunocompromised due to any cause, including medications or HIV infection. 3
• Persons with extreme obesity (BMI ≥40). 3

Pregnancy and Postpartum

• All pregnant women at any stage of pregnancy should receive vaccination to protect both mother and infant through transplacental antibody transfer. 1, 5
• Pregnant women may receive any licensed, recommended, age-appropriate influenza vaccine. 3
• All breastfeeding women should be vaccinated, as vaccination is safe for mothers and infants. 1

Healthcare Personnel and Caregivers

• All healthcare personnel, including physicians, nurses, medical emergency-response workers, and nursing home staff, should receive vaccination to prevent healthcare-associated influenza infections. 3, 1
• Vaccination of healthcare workers is associated with decreased mortality among nursing home patients. 6
• All child care providers and staff should be vaccinated. 1

Timing of Vaccination

Optimal Timing

• Vaccinate as soon as vaccine is available, ideally by the end of October. 3, 1
• Children aged 6 months through 8 years requiring 2 doses should receive their first dose as soon as possible to allow the second dose (≥4 weeks later) to be received by end of October. 3

Late Season Vaccination

• Vaccination administered in December or later is still beneficial even if influenza activity has already begun, as influenza activity can peak as late as March. 3, 6
• Do not delay vaccination in high-risk populations even late in the season. 6

Post-Influenza Infection Vaccination

Key Principle

• The primary consideration is clinical recovery from acute febrile illness, not a specific time interval after infection. 6
• Confirm resolution of fever without antipyretics and ensure acute symptoms have substantially improved before administering vaccine. 6

Urgent Post-Recovery Vaccination

• High-risk individuals (adults ≥65 years, children 6-59 months, persons with chronic pulmonary disorders) should be prioritized for vaccination immediately upon recovery. 6
• Do not assume recent influenza infection provides adequate protection for the remainder of the season. 6

Administration Details

• Administer intramuscularly in the deltoid muscle for adults and older children. 4, 6
• For infants and young children, use the anterolateral thigh. 6
• It takes approximately 14 days after vaccination for a healthy adult to reach peak antibody protection. 5

Common Pitfalls to Avoid

• Do not use LAIV4 due to low effectiveness against influenza A(H1N1)pdm09 in the 2013-14 and 2015-16 seasons. 3
• Do not withhold vaccination due to concerns about Hashimoto's thyroiditis—autoimmune thyroid disease is not a contraindication. 4
• Do not delay vaccination waiting for "better timing"—missed opportunities result in unprotected individuals. 3
• The estimated risk of Guillain-Barré Syndrome is approximately one additional case per million persons vaccinated, which is minimal compared to benefits. 4

Vaccine Effectiveness Considerations

• Even with suboptimal strain matching, vaccination provides meaningful protection against severe outcomes (hospitalization, ICU admission, death). 7
• Vaccine effectiveness is lower in elderly populations but still provides substantial benefit. 6
• Annual vaccination is necessary because immunity declines within one year. 1