ARPANSA claim that 5G doesn’t affect the immune system.
ARPANSA doesn’t seem to be aware of research papers indicating an impact on immunoglobulin and other markers which are intrinsically linked to immune responses. Here follows a little more about them. 
The abstract of the Johansson paper includes, “A number of papers dealing with the effects of modern, man-made electromagnetic fields (EMFs) on the immune system are summarized in the present review. EMFs disturb immune function through stimulation of various allergic and inflammatory responses, as well as effects on tissue repair processes.” The paper is a review and this is the full reference: Johansson O. 2009. Disturbance of the immune system by electromagnetic fields: A potentially underlying cause for cellular damage and tissue repair reduction which could lead to disease and impairment. Pathophysiology 16:157-177.
The El-Gohary & Said (2017) paper included this in the abstract: “[Method] …Group III: exposed to EMF 1 h/day; Group IV: exposed to EMF 2 h/day; ….[Results] After 30 days of exposure time, 1 h/day EMF exposure resulted in significant decrease in immunoglobulin levels (IgA, IgE, IgM, and IgG); total leukocyte, lymphocyte, eosinophil and basophil counts; and a significant increase in neutrophil and monocyte counts. These changes were more increased in the group exposed to 2 h/day EMF.”
Its full reference is: El-Gohary OA, Said MA-A. 2016. Effect of electromagnetic waves from mobile phone on immune status of male rats: Possible protective role of vitamin d. Canadian Journal of Physiology and Pharmacology 95:151-15

Here is a little info about  immunoglobulins: “Immunoglobulins, also known as antibodies, are glycoprotein molecules produced by plasma cells (white blood cells). They act as a critical part of the immune response by specifically recognizing and binding to particular antigens, such as bacteria or viruses, and aiding in their destruction.” from:

As always, my attitude is that by learning about what the research indicates about effects of RF we equip ourselves to make informed decisions. 
Dr Mary Redmayne