Jheronimus Bosch (ca. 1450 - 1516) was one of the most influential representatives of the Early Netherlands School of painting. His remaining oeuvre is small and includes the altar piece Christ Carrying the Cross. This painting probably was part of a triptych, but the other parts are lost. The reverse side of the painting depicts a naked child with a walking frame and a paper windmill. The iconographical meaning of both walking frame and windmill are disputed [1]. It is safe to assume that the boy is the Christ Child, taking his first steps (Christ carrying the Cross are Christ’s last steps) and the windmill could allude to the Cross itself (Figure 1).

A walking frame assists young children in the development of the skill of walking: all bones, joints, muscles and tendons are in place but need to be functionally developed and trained. A parallel can be drawn with the development of the immune system. Children are born with a complete repertoire of T- and B-lymphocytes, but also the immune system needs to be developed and trained. In young children, every antigen, every pathogen encountered will induce a primary immune response. For a number of pathogens, a primary immune response takes too long and is not strong enough. For full protection against those pathogens, support of the immune system is needed in the form of vaccination.

At the end of life, the ability to walk and maintain balance becomes impaired. Because the consequences of falling can be serious, a walking frame is used to retain the skill of walking [2]. Also, in this case the parallel with the immune system can be made: support of the aging immune system by vaccination is needed, especially against influenza and pneumococcal infections [3,4]. We can be pretty sure that it was not the intention of Jheronimus Bosch to refer to the development of the immune system when designing Christ Child with a Walking Frame. But that is what gives this painting a universal meaning.

Figure 1: Christ Child with a Walking Frame. Back panel of the painting Christ Carrying the Cross by Jheronimus Bosch (ca1490-1510) Kunsthistorisches Museum, Vienna, Austria. https://upload.wikimedia.org/wikipedia/commons/5/57/Hieronymus_Bosch_101.jpg Assessed February 14, 2019

1.       Gibson WS (1975) Bosch's Boy with a Whirligig: Some Iconographical Speculations. Simiolus: Netherlands Quarterly for the History of Art 8: 9-15.

2.       Costamagna E, Thies SB, Kenney LPJ, Howard D, Liu A, et al. (2017) A generalizable methodology for stability assessment of walking aid users. Med Eng Phys 47: 167-175.

3.       Pinti M, Appay V, Campisi J, Frasca D, Fülöp T, et al. (2016) Aging of the immune system: Focus on inflammation and vaccination. Eur J Immunol 46: 2286-2301.

4.       Rijkers GT, Yousif LI, Spoorenberg SM, van Overveld FJ (2018) Triptych of the Hermit Saints: pneumococcal polysaccharide vaccines for the elderly. Risk Manag Healthc Policy 11: 55-65.