Twins with at least one with CHD and their immunisation status in direct comparison—are both twins complying with the German immunisation recommendations?

In the direct twin comparison, twins are similarly vaccinated except for RSV and influenza. Immunisation against influenza in twins should be improved. With new upcoming RSV vaccines, existing recommendations must be reconsidered and adapted. Another disturbing fact is that only 30% of infants are vaccinated against pertussis and pneumococcus within the primary recommended timeframe, even though they are exposed at high risk during infancy. Further education of parents, patients, and medical staff might lead to higher vaccination coverage, especially in pneumococcal vaccines recommended for high-risk patients. We must provide sufficient information on the importance of vaccinations and their side effects for parents' and patients' decision-making.