- Firstly, I had never read before that the first person to suggest that helminth infection was a potential reason for the increased prevalence of chronic inflammatory diseases was first proposed as early as 1968 by a Dr. Greenwood, who was attempting to explain the low prevalence of autoimmune diseases in Nigeria. For 50 years, then, the concept of helminths’ anti-inflammatory properties has been in the medical literature. WOW.
- The author, Dr. Caraballo, states that the strength of the infection is important in terms of the anti-inflammatory effects. Genetic factors may play a role here in that some people may have a better ability to control helminth populations. That’s a really interesting point and may well explain why people doing helminthic therapy need such widely varying doses for efficacy.
- Helminths’ immunomodulatory ability “…is now a well-known phenomenon that depends on several factors such as intensity and chronicity of infection, host genetic background, type of parasite and probably poly parasitism.” This is the only the second article I have read that mentions that the anti-inflammatory effect of helminths requires long-term helminth exposure. (It also makes it very odd that the human clinical studies that have been done were only about 12 weeks long!) I am also glad the author mentioned the idea of more than one parasite. I can remember reading only 1 article in the literature looking at this phenomenon, which noted that those with more than 1 had markedly higher levels of anti-inflammatory cytokines, like IL-10.[ii]
In his conclusion, Dr. Caraballo points out that there are many risk factors that need to be studied in tandem to really understand the epidemic of inflammatory illness, including not only the loss of our native macrobiomes but also, microbial infections, alterations of the microbiota, pollution and so forth. Unfortunately, he doesn’t mention diet specifically (and the lack of fiber in the normal Western diet), but I suppose this can be included in the microbiota alterations category!
[i] Caraballo, L. The tropics, helminth infections and hygiene hypotheses. Expert Review of Clincal Immunology. 2018 Jan 4. doi: 10.1080/1744666X.2018.1424543
[ii] Turner, JD, et. al. Intensity of intestinal infection with multiple worm species is related to regulatory cytokine output and immune hyporesponsiveness. The Journal of Infectious Diseases 2008; 197:1204 –12. DOI: 10.1086/586717