Infant in doctor's office

The fight against the COVID-19 pandemic relied heavily on stay-at-home orders and vaccines, but their effects have also impacted other areas of public health sectors. Routine childhood vaccinations are one of these areas, which have experienced a decline because of delayed or missed vaccinations.  

The pandemic caused a reduction in in-person visits and fear of visiting medical offices, leading to a decrease in vaccinations, according to Francis Chan, MD, FAAP, FACP, chair of the Department of Pediatrics at Loma Linda University Health. This was further compounded by widespread vaccine misinformation and parent hesitancy, which was exacerbated by concerns surrounding COVID-19 vaccines, according to Chan. 

Recent data from electronic health records (EHR) suggest the pandemic led to a 42% decrease in immunization administrations for pediatric patients in the spring of 2020 compared to previous years. 

“The consequence is that they will be at a higher risk of becoming infected with vaccine-preventable diseases such as measles, mumps, rubella, polio, and pertussis,” said Chan.  

Pediatric vaccination rates have since improved from their pandemic lows, with patients aged six years and younger receiving almost all the expected immunizations. However, patients aged 7-12 years old received fewer immunizations than expected, and patients aged 13-18 years old continued to show the largest gap between expected and received immunizations, according to EHR.  

Herd immunity for childhood MMR (measles, mumps, and rubella) is typically achieved when at least 95% of the population is vaccinated against these diseases. Herd immunity, or community immunity, is used to describe a situation where a high percentage of a population is immune to a particular disease, either through vaccination or natural infection.

Vaccines stimulate the body's immune system to produce antibodies that protect people from serious, often life-threatening diseases.  

“Think of the immune system like memory,” Chan said. “The more times you are exposed to something such as 2+2 =4, the more likely you will remember it. By receiving a vaccine, your immune system is exposed to the virus or bacteria protein and subsequently builds antibodies to those foreign proteins. If and when you are exposed to the real virus or bacteria, your body will ‘remember’ that this is something foreign. Your immune system will then be able to more quickly escalate a response to fight off the infection.”

Although pediatric vaccination rates have improved since the pandemic, there is still work to be done. Health officials are stressing the importance of catching up on routine vaccinations and have implemented programs to ensure children and adults who missed their vaccines during the pandemic can receive them and prevent disease outbreaks. 

“There is a catch-up process where some vaccine doses may be decreased depending on the patient's age and risk of getting the disease or its severity. For example, if a child normally receives five doses of a vaccine, they may only receive four,” Chan said.  

The Centers for Disease Control and Prevention (CDC) has created a catch-up schedule for children who are behind on immunizations.  

To learn more about immunizations, talk to your doctor or schedule an appointment online