According to a new CDC report, fewer children born during the first two years of the COVID pandemic received recommended vaccines compared to those born two years before the pandemic. Compared with vaccine coverage during 2018 and 2019, estimated coverage for children born in 2020 and 2021 declined by 1.3 to 7.8 percentage points, depending on the vaccine.

Most of us who follow vaccines believed vaccination rates were down because many parents avoided bringing their children or themselves to healthcare facilities during the pandemic. I assume that other healthcare metrics will show similar changes during the pandemic across all age groups.

Given the fact that pediatric vaccines have prevented half a billion illnesses since 1994, it is important that we reverse this trend as quickly as possible, or we may see the return of outbreaks of diseases that we thought were long gone.

This post will review the data from the CDC and examine what it might mean.

Pandemic effect on children vaccines rate

In a paper published on 26 September 2024 in the CDC’s peer-reviewed MMWR Morbidity and Mortality Weekly Report, Holly Hill, MD, PhD, CDC National Center for Immunization and Respiratory Diseases, and colleagues utilized data from the National Immunization Survey, a nationwide survey of U.S. parents or guardians of children ages 19 to 35 months. The researchers collected data during household telephone interviews and reviewed vaccination records from the children’s healthcare providers.

Here are the key results:

• Influenza vaccine, two or more doses: -7.8 percentage points (the largest drop in vaccination rate)
• Rotavirus vaccine: -2.0 percentage points
• Diphtheria, tetanus, pertussis (DTaP) vaccine: -1.8 percentage points for three or more doses; -2.5 percentage points for four or more doses
• Haemophilus influenzae type b (Hib) conjugate vaccine: -2.2 percentage points for the primary series; -3.2 percentage points for the full series
• Pneumococcal conjugate vaccine (PCV): -1.8 percentage points for three or more doses; -2.7 percentage points for four or more doses
• Hepatitis A vaccine, one or more doses: -1.6 percentage points
• Measles, mumps, and rubella (MMR) vaccine: -1.7 percentage points
• Poliovirus vaccine: -1.5 percentage points
• Varicella (chickenpox) vaccine (VAR): -1.3 percentage points
• Hepatitis B vaccine (Hep B), three or more doses: -1.5 percentage points
• Combined seven-vaccine series (includes ≥4 doses of DTaP, ≥3 doses of poliovirus vaccine, ≥1 dose of measles-containing vaccine, the full series of Hib (≥3 or ≥4 doses, depending on product type), ≥3 doses of HepB, ≥1 dose of VAR, and ≥4 doses of PCV): -3.2 percentage points

The authors recommended several tactics to reverse the decline in vaccines given to children post-pandemic.

First, they recommended higher provider participation in the Vaccines for Children Program, which provides free vaccines to all children in the USA. As I wrote previously, the program has been overwhelmingly effective in protecting children from many dangerous and deadly diseases.

The authors also made other recommendations to improve vaccination rates:

• Use of standing orders to prompt parents to vaccinate their children.
• Stronger physician recommendations for vaccination.
• Providing vaccines in alternative settings, such as pharmacies.

Summary

Despite the decreases in vaccine uptake shown in this report, there was some encouraging data. For example, vaccine rates for poliovirus, MMR, DTaP, Hib, and Hep B remained above 90% for children born in 2020 and 2021. The 90% rate is key because that is the point where most vaccines provide herd effect protection.

Unfortunately, there is a lot of bad news in this report — for example, only 56% of children received their influenza vaccine during 2020-2021 which is down from 63% in 2018-2019.

Possibly as a result of the declining vaccination rate, measles cases have dramatically increased in the USA. Furthermore, the CDC has recently reported that cases of whooping cough are five times higher this year than at the same point in 2023. Are these increases caused by the lower vaccination rate? Possibly.

We need to do what we can to increase vaccine uptake for children to pre-pandemic levels (and higher), so that we prevent outbreaks of dangerous diseases. That’s up to a lot of people involved in public health, and I hope that the strategies and tactics start today.

Citations

• Hill HA, Yankey D, Elam-Evans LD, Mu Y, Chen M, Peacock G, Singleton JA. Decline in Vaccination Coverage by Age 24 Months and Vaccination Inequities Among Children Born in 2020 and 2021 – National Immunization Survey-Child, United States, 2021-2023. MMWR Morb Mortal Wkly Rep. 2024 Sep 26;73(38):844-853. doi: 10.15585/mmwr.mm7338a3. PMID: 39325676.