Did you ever wonder if antibiotics might influence the immune response to a vaccine? Could the use of an antibiotic impact the effectiveness of childhood vaccines? To address this question, Chapman et al (10.1542/peds.2021-052061) share with us an analysis involving a secondary analysis of a prospective cohort study evaluating respiratory infections, including otitis media, in the primary care setting. The authors re-analyzed data they collected that compared use of antibiotics by children ages 6 to 24 months, vaccine records, and antibody levels to routine childhood vaccines given in the first 2 years of life.
Of the 560 children in this study, 342 had previously received prescriptions for antibiotics and 218 did not. Receipt of antibiotics was associated with reduced vaccine-induced antibody levels to several diphtheria, tetanus, and pertussis (DTaP), and pneumococcal antigens. More children who received antibiotics had vaccine antibodies below protective levels. Furthermore, lower antibody levels were associated with greater use of antibiotics over time (e.g., more frequent prescriptions, longer duration) and receipt of broad-spectrum antibiotics.
What does this association mean? We invited Drs. Octavio Ramiro and Asuncion Mejias from Nationwide Children’s Hospital to help interpret these findings in an accompanying commentary (10.1542/peds.2021-055610). The commentary notes the role that the microbiome may be playing in immune regulation, and how antibiotic treatment may alter the microbiome and impact immune development. One of the limitations of the study is that the microbiome was not evaluated. Another limitation is that the study was underpowered to determine whether individuals had greater susceptibility to infection after antibiotic exposure.
Drs. Ramiro and Mejias still find these results in this study “remarkable” and call for this study being a launching pad for larger prospective multicenter studies. While we are all familiar with the importance of being good stewards of antibiotics to prevent bacterial resistance, this study offers another good reason to remain vigilant in use of antibiotics and make sure the benefits of their use outweigh the risks. Link to this study and commentary and learn more.