Influenza key points

Healthcare providers and local public health departments are instrumental in preventing and controlling the spread of influenza in Massachusetts. Here are some important updates for this year:

2021-2022 Recommendation Highlights

Table of Contents

Influenza Activity During the 2020-2021 influenza Season


Flu activity was unusually low throughout the 2020-2021 flu season both in the United States and globally, despite high levels of testing. During September 28, 2020–May 22, 2021 in the United States, 1,675 (0.2%) of 818,939 respiratory specimens tested by U.S. clinical laboratories were positive for an influenza virus. The low level of flu activity during this past season contributed to dramatically fewer flu illnesses, hospitalizations, and deaths compared with previous flu seasons. For comparison, during the last three seasons before the COVID-19 pandemic, the proportion of respiratory specimens testing positive for influenza peaked between 26.2% and 30.3%. In terms of hospitalizations, the cumulative rate of laboratory-confirmed influenza-associated hospitalizations in the 2020-2021 season was the lowest recorded since this type of data collection began in 2005. CDC received one report of a pediatric flu death during the 2020–2021 flu season. Since flu deaths in children became nationally notifiable in 2004, reported flu deaths in children had previously ranged from a low of 37 (during 2011-2012) to a high of 199 (during 2019-2020).

COVID-19 mitigation measures such as wearing face masks, staying home, hand washing, school closures, reduced travel, increased ventilation of indoor spaces, and physical distancing, likely contributed to the decline in 2020-2021 flu incidence, hospitalizations and deaths. Influenza vaccination may also contributed to reduced flu illness during the 2020–2021 season. Flu vaccine effectiveness estimates for 2020-2021 are not available, but a record number of influenza vaccine doses (193.8 million doses) were distributed in the U.S. during 2020-2021. 


Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices — United States, 2021-2022 Influenza Season has been published. CDC recommends annual influenza vaccination for everyone 6 months and older who do not have contraindications.

For more information on this year’s flu recommendations, see:

There are some websites that help providers and patients locate vaccines and Influenza antivirals:

Flu vaccine locations

Find out where you can get a flu vaccine by asking your primary care provider, going to a local pharmacy, or visiting Find your flu vaccine.

COVID-19 vaccine locations

Search VaccineFinder for a site near you.    

Influenza disease burden

The burden of disease is great. CDC estimates that influenza has resulted in between 9 million and 45 million illnesses, between 140,000 and 810,000 hospitalizations and between 12,000 and 61,000 deaths annually since 2010.

CDC now posts preliminary estimates of the influenza disease burden.

The good news is this year’s influenza vaccines have been updated to better match circulating viruses.

Your strong recommendation is important!

A health care provider’s strong recommendation is a critical factor affecting whether your patent gets influenza vaccine. Patients listen to providers when providers strongly recommend vaccination.

  • There are many misconceptions about flu vaccine.  CDC addresses many of these misconceptions and provides a summary of the benefits of vaccination and selected scientific studies that support these benefits.
  • Flu vaccine is recommended for everyone 6 months of age and older who do not have contraindications. While some flu formulations are not recommended for some patients and some patients should not receive flu vaccine at all, this is uncommon.  For more guidance on contraindications and precautions for influenza vaccine, please see Table 2 on page 4 and pages 17-20 in the 2021-2022 ACIP Influenza Recommendations.

Below are and links to the latest information and data that might inform your conversations with patients in the upcoming months:

  • Flu vaccine offers the best protection against flu-related illness, hospitalization, and death. Flu vaccine reduces this burden of illness. For the latest information about vaccine effectiveness, see CDC’s Influenza Vaccine Effectiveness Studies website.
  • Influenza vaccination was found to reduce deaths in children. A study in Pediatrics was the first of its kind to show that influenza vaccination is effective in preventing influenza-associated deaths among children
  • Influenza vaccination may make illness milder. While some people who get vaccinated may develop influenza, vaccination may make their illness milder. A 2017 study in Clinical Infectious Diseases (CID) showed that influenza vaccination reduced deaths, intensive care unit (ICU) admissions, ICU length of stay, and overall duration of hospitalization among hospitalized influenza patients.
  • Influenza vaccination has been found effective in preventing influenza-associated hospitalization during pregnancy.

For more information on questions and answers related to this flu season, please see the General information about flu page.

Vaccine supply

MDPH universally provides influenza vaccine, as well as other routinely recommended vaccines, to all children through 18 years of age. MDPH only provides influenza vaccine for uninsured adults seen at public sites. For more information on state-supplied vaccine, please see the Vaccine Management page. 

Nationally, manufacturers have projected they will provide as many as 188-200 million doses of flu vaccine this season.Information about the national vaccine supply can be found at CDC’s Seasonal Influenza Vaccine Supply & Distribution website.  

The Immunization Action Coalition (IAC) has a very helpful table of the Influenza Vaccine Products for the 2021-2022 Influenza Season.

When to vaccinate

Optimally, vaccination should occur before the onset of influenza activity in the community. CDC recommends flu vaccination by the end of October, if possible. This year it is particularly important that vaccination efforts continue into November, the winter months and throughout the season, as both flu and COVID-19 will be active in the U.S. The duration of the influenza season varies from, year to year and influenza activity might not occur in certain communities until February or March. In New England, flu activity usually lasts until April and May.

To avoid missed opportunities, providers should continue to offer vaccination during routine health care visits and hospitalizations. Immunization providers might need to adapt and extend the duration of vaccination campaigns to accommodate stay at home efforts and social distancing aimed at slowing the spread of COVID-19.

Safe influenza vaccine administration

CDC provides comprehensive vaccine administration resources, including Vaccine Administration eLearn at their Vaccine Administration website.

Vaccine information statement

The most recent versions of Vaccine Information Statements (VISs) for Influenza Vaccines (IIV and LAIV4) for use this season are dated 8-06-21 interim.  The latest versions of all the VISs can be found at this site.


2021-2022 Influenza Season

Centers for Disease Control and Prevention

Immunization Action Coalition


  • VaccineFinder ( a user-friendly, website where users can search for locations that offer seasonal flu vaccine and other adult immunizations. Just in time for flu season, the Vaccine Finder website has been upgraded and participating providers can now update supply estimates for a more accurate reporting.

American Academy of Pediatrics

American College of Physicians

American Academy of Family Physicians

American College of Obstetricians and Gynecologists

Children’s Hospital of Philadelphia




Infectious Disease Division (617) 983-6550
Urgent calls and infectious disease reporting (617) 983–6800
Laboratory Sciences Division (617) 983–6201


State Public Health Laboratory
305 South Street
Jamaica Plain, MA 02130