IACFS/ME Conference – Dr Leonard Jason “Predictors for Developing Severe Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Following Infectious Mononucleosis

October 14, 2021

The 2nd Virtual Scientific Conference for the International Association for Chronic Fatigue Syndrome/ Myalgia Encephalomyelitis was held on the 19th – 21st August 2021 (streamed on zoom). The conference promoted unpublished data and included both clinicians and biomedical researchers. 

The talks were grouped into different sections, including the longer 45 minute talks in the Professional Workshops and shorter talks covering topics of infectious diseases, immunology and clinical cases. 

We have chosen a selection of the talks which will hopefully be of interest to you, which are listed below. Here we report on our eighth talk in this series with a talk from Dr Leonard Jason who’s second talk in the IACFS/ME conference covered his study on predicting ME/CFS from following a group of college students with his presentation titled “Predictors for Developing Severe Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Following Infectious Mononucleosis”. The further talks we will cover are shown below and these will be available in one report by the end of October 2021. 

Due to the format of the conference and the focus on unpublished data, no direct recordings or pictures are available freely as this may jeopardise publication. The full conference programme can be found on the IACFS/ME website here, where recorded presentations may be purchased. 

8. Predictors for Developing Severe Myalgic Encephalomyelitis / Chronic Fatigue Syndrome Following Infectious Mononucleosis  

Leonard A. Jason, PhD 
DePaul University; Chicago, Illinois, USA 

Dr Leonard Jason presented his second presentation of the IACFS/ME conference on predictors for developing ME/CFS following infectious mononucleosis (symptoms are usually caused by the Epstein-Barr virus) (his first presentation was on long-covid, see talk 6). The study that Dr Jason presented on is the first longitudinal study of ME/CFS prior to the onset of the illness, which was conducted by studying college students. The study found some baseline deficiencies and predisposing immune response irregularities in people who go on to develop severe ME/CFS. 

Dr Jason’s study was conducted between 2014 and 2018, using 4501 healthy college students, following which 5% went on to develop infectious mononucleosis. Subsequently, 8% of this group went on to develop severe ME/CFS symptoms at a 6-month follow up. This study has been published in the journal of Clinical Infectious Diseases (Jason et al., 2020). 

Dr Jason explained some of the immune findings when looking at the pro and anti-inflammatory cytokines, interconnections in the immune system were found but in the controls the cytokines were in clustered separated groups whereas in people who went on to develop severe ME/CFS cytokines were more grouped together. 

Dr Jason gave an overview of the baseline data differences seen, DSQ, IL13 and IL5 assessments were used to compare between severe ME/CFS and controls. In all baseline assessments people that went on to develop ME/CFS had higher scores indicating more problems, which was also significantly different between groups. Looking into the DSQ assessments in more detail showed more differences in the gastrointestinal symptoms.  In particular those who went on to develop severe ME/CFS had more problems with bloating, stomach pain and irritable bowels.  

Dr Jason explained some of the problems they had had analysing the data, in which they carried an index for predictive purposes which was difficult and had many challenges. However, the final result showed that an increase of one on the index corresponded to a 55% increase in the chance of developing severe ME/CFS. Dr Jason will extend this study, including by evaluating another data set using GI symptoms. 

Dr Jason ended by talking about the funding that has been received from the NIH to conduct a six year follow-up study on the same student data set. He also finished by saying that this study will have particular relevance for long-covid where data can be used to predict for ME/CFS and Long-covid. Dr Jason gave his thoughts on the long-covid definition currently being developed by WHO which should include: variation, duration, medical history (cardiac problems in particular) and whether mild, moderate or severe.   

Katrina Pears, Research Correspondent, ME Association  


Professional Workshops

Alison Bested, MD, FRCPC, ABOIM
Chair, Integrative Medicine, Associate Professor
Nova Southeastern University; Weston, FL, USA  

Blair Grubb, MD
University of Toledo; Toledo, OH, USA

Carmen Scheibenbogen, MD  
Institute for Medical Immunology, Charité University Medicine (Germany)  

Larry Afrin, MD
AIM Center for Personalized Medicine; Purchase, NY, USA    


Avindra Nath, MD
US National Institutes of Health, NINDS; Bethesda, MD, USA    

Infectious Disease

Leonard Jason, PhD
DePaul University; Chicago, Illinois, USA  

Provocation Studies 1


Neurology/ Epidemiology

Clinical cases

Hector Bonilla, MD
Stanford University; Stanford, CA, USA  

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