MD MOLD | BUILDING SCIENCE, Mold & INDOOR AIR QUALITY

CIRS and Mold: When Your Building Makes You Chronically Ill

A look at Chronic Inflammatory Response Syndrome, genetic susceptibility, and what a professional mold inspection can mean for your long-term health.

Published March 2026 | MD Mold Building Science Consulting

Important Note: CIRS is not currently recognized as an established diagnosis by mainstream medicine. It has no assigned ICD-10 code, and the Shoemaker Protocol is considered investigational by most major insurers and health systems. The clinical literature on CIRS is largely produced within a small community of practitioners and advocates, and significant debate continues regarding diagnostic criteria, biomarker validity, and treatment evidence. This article presents the framework as described by its proponents alongside those caveats.

What Is CIRS?

Chronic Inflammatory Response Syndrome (CIRS) is a term coined by Dr. Ritchie Shoemaker to describe a multi-system, multi-symptom illness he proposes is driven by a sustained dysregulation of the innate immune system, most commonly triggered by exposure to the interior environment of a water-damaged building (WDB). The biotoxins implicated include mycotoxins from mold species, bacterial endotoxins from actinomycetes, and microbial volatile organic compounds (mVOCs) that can become airborne and inhaled in contaminated spaces.

The CIRS framework originated in 1997, when Shoemaker — then a rural family physician in Pocomoke, Maryland — linked a cluster of unexplained multi-symptom illness in patients to exposure to a toxin produced by the dinoflagellate Pfiesteria. He subsequently proposed that the same biological pattern applied to mold-impacted buildings, and over the following years documented what he identified as consistent symptom clusters and biomarker abnormalities in patients with WDB exposure. Researchers affiliated with the Surviving Mold organization have since linked similar presentations to Stachybotrys chartarum, Aspergillus, Penicillium, Chaetomium, Wallemia, and other water-damage-indicator genera.

According to Shoemaker’s estimates, cited in the Berndtson clinical overview published on SurvivingMold.com, approximately 75% of CIRS cases are attributed to WDB exposure, making mold the most commonly identified biotoxin trigger within this framework.

The Scale of the Problem

Two data points are central to the CIRS public health argument. First, according to the U.S. Government Accountability Office (GAO-08-980, 2008), approximately 50% of buildings in the United States have some form of water damage sufficient to support mold and microbial growth. Second, Shoemaker’s research on HLA-DR genetics proposes that roughly 24–25% of the general population carries gene variants that impair the body’s ability to recognize and clear biotoxins. In susceptible individuals, the argument goes, those toxins continuously reactivate the innate immune system rather than being neutralized and excreted.

A 2024 peer-reviewed literature review published in Annals of Medicine & Surgery (Dooley, Vukelic & Jim; PMC11623837) estimated that at least 52.1 million Americans are predisposed to developing CIRS from WDB exposure, based on McMahon’s 2017 prevalence analysis. The same paper calculated a conservative CIRS prevalence of at least 7.01% in children, likely higher in adults due to what the authors describe as the progressive, cumulative nature of the condition. It should be noted that two of the three authors of this review provide expert witness testimony in CIRS litigation, a conflict of interest disclosed in the paper itself.

Despite this proposed disease burden, CIRS remains widely unrecognized in mainstream clinical practice and is frequently misattributed to ME/CFS, fibromyalgia, anxiety, or other diagnoses.

The Biology: Why Some People Get Sick and Others Don’t

One of the most clinically discussed aspects of the CIRS framework is the question of differential susceptibility: why two people in the same moldy building can have profoundly different outcomes. Within the CIRS model, the answer lies in HLA (Human Leukocyte Antigen) genetics on chromosome 6 — the gene system that encodes proteins enabling the immune system to identify foreign invaders and mount antibody responses.

In the approximately 75% of the population without susceptible HLA haplotypes, the immune system correctly identifies mycotoxins as antigens, produces neutralizing antibodies, and clears them through normal excretory pathways. In individuals carrying susceptible HLA-DR variants — estimated at 24–25% of the population in Shoemaker’s research — this recognition step is proposed to fail. Biotoxins instead accumulate in lipid-rich tissues, particularly nerve cell membranes, while the innate immune system continues firing in a futile attempt to eliminate a threat it cannot properly tag for clearance.

The susceptible HLA-DR marker is reported to be present in approximately 90% of patients who seek specialty evaluation for mold-exposure injuries (Mastery Medical/Jim), lending biological plausibility to the genetic susceptibility model — though critics note that this population represents a self-selected group already seeking a CIRS diagnosis.

Symptoms: A Multi-System Illness

In his original clinical description, Shoemaker identified 37 symptoms that differentiated CIRS patients from healthy controls (confirmed in Dooley et al., 2024). Because the innate immune system regulates virtually every organ system, CIRS presentations are characteristically broad. Common documented presentations include:

• Cognitive: brain fog, memory impairment, difficulty concentrating, confusion

• Neurological: headaches, tremors, tingling, numbness, balance disturbances

• Respiratory: chronic cough, shortness of breath, recurrent sinusitis

• Musculoskeletal: joint pain, muscle aches, morning stiffness, weakness

• Gastrointestinal: abdominal pain, nausea, diarrhea, new food sensitivities

• Endocrine/metabolic: fatigue, night sweats, weight dysregulation, light sensitivity

• Neuropsychiatric: mood swings, anxiety, depression, insomnia

Because these symptoms overlap substantially with ME/CFS, fibromyalgia, and Lyme disease, the CIRS-treating community reports that patients commonly cycle through multiple providers before reaching a mold-literate clinician. In practices specializing in CIRS, the average patient is reported to present with more than 20 concurrent symptoms at the time of evaluation.

The Immunological Cascade: Key Biomarkers

A key argument for CIRS as a distinct clinical entity is the presence of measurable, reproducible laboratory abnormalities. The Dooley et al. (2024) review confirms that CIRS is typically associated with reduction in the regulatory neuropeptide MSH, and elevation in at least one of TGF-β1, C4a, and MMP-9, along with possible dysregulation of ACTH/cortisol, ADH/osmolality, gliadin antibodies, anticardiolipin antibodies, and VEGF.

Inflammatory Cytokines (TGF-β1, TNF-α, IL-6)

Elevated pro-inflammatory cytokines are a hallmark of CIRS as described in the Shoemaker literature. TGF-β1 in particular has been identified as a reliable marker of biotoxin-driven innate immune activation. Elevated cytokines are also proposed to interfere with leptin receptor signaling, suppressing MSH — a regulatory neuropeptide that governs pain sensitivity, sleep, melatonin production, and hormonal balance.

Matrix Metalloproteinase-9 (MMP-9)

MMP-9 is an enzyme that, when chronically elevated, is proposed to disrupt the blood-brain barrier — a mechanism that proponents argue explains the cognitive and mood symptoms seen in CIRS. Shoemaker et al.’s 2014 NeuroQuant volumetric MRI study of 17 CIRS-WDB patients documented statistically significant structural brain differences compared to 18 controls, including caudate nucleus atrophy and pallidum enlargement.

Complement Proteins (C3a, C4a)

Elevated C4a is considered within the CIRS model to be one of the more sensitive early indicators of mold biotoxin exposure. The claim that C4a rises within 12 hours of re-exposure is cited in some secondary CIRS literature but we were unable to confirm this specific timeframe against a primary peer-reviewed source; it should be treated with appropriate caution.

VEGF (Vascular Endothelial Growth Factor)

VEGF is reported to be suppressed in CIRS, with the Shoemaker literature documenting that approximately one-third of CIRS-WDB patients have VEGF below 31 and another third above 86 (both representing dysregulation). This is proposed to result in inadequate tissue oxygenation contributing to the profound fatigue characteristic of the condition.

Diagnosis

The CIRS diagnostic criteria were formalized through the Surviving Mold Consensus Committee in 2018 (Shoemaker, Johnson, Jim et al., Int Med Rev). A diagnosis requires convergence of:

• A history of exposure to a documented biotoxin source (e.g., WDB confirmed by ERMI/HERTSMI-2 testing)

• Symptom clusters consistent with biotoxin illness

• A susceptible HLA-DR haplotype on genetic testing

• Abnormal Visual Contrast Sensitivity (VCS) testing

• Biomarker abnormalities consistent with the neuroimmune/vascular disruption profile of CIRS

It is important to note that these criteria are not universally accepted by mainstream medicine. A December 2024 policy review by AmeriHealth Caritas and other insurers found that CIRS has no ICD code and that the evidence base consists primarily of two single-author narrative reviews, with insufficient independent replication to meet standard clinical policy thresholds. UCLA Health similarly characterizes CIRS as not an established medical diagnosis as of 2025.

Within the CIRS-treating community, an ERMI score of 5 or higher is used as a trigger for clinical investigation. ERMI (Environmental Relative Moldiness Index) testing uses qPCR analysis of settled dust to quantify mold DNA by species, providing an objective, species-resolved picture of the mycological burden in a building. At MD Mold, our in-house qPCR laboratory performs this analysis as a core component of our inspection and clearance workflow.

Treatment: The Shoemaker Protocol

A 2024 literature review in Annals of Medicine & Surgery (Dooley et al., PMC11623837) examined all published evidence for CIRS treatment and found the Shoemaker Protocol to be the only intervention with documented clinical efficacy across the peer-reviewed literature reviewed — appearing in 11 of 13 identified CIRS treatment articles. However, the authors acknowledged that the literature base is limited, and that major health bodies have not formally endorsed the protocol.

The protocol is a sequential 12-step framework, beginning with two environmental steps:

• Step 1 – Remove the patient from biotoxin exposure. No downstream treatment is considered effective while ongoing exposure continues. This requires validated environmental clearance, not just visual inspection.

• Step 2 – Bind circulating biotoxins using bile acid sequestrants (cholestyramine or Welchol), which intercept mycotoxins in the gastrointestinal tract before enterohepatic recirculation.

Subsequent steps address MARCoNS (Multiple Antibiotic Resistant Coagulase Negative Staphylococci — nasal biofilm bacteria that further suppress MSH), gliadin antibodies, DHEA/androgen depletion, and sequential correction of ADH/osmolality, MMP-9, VEGF, C3a, C4a, and TGF-β1 abnormalities. The final step for patients requiring it is treatment with Vasoactive Intestinal Peptide (VIP). A September 2025 review by Dorninger (ND, LAc) in Medical Research Archives provides a comprehensive clinical walkthrough of the protocol’s rationale and evidence base.

Limitations of the protocol are acknowledged even by its proponents: many treatments require indefinite continuation to maintain health gains, and cost, adherence challenges, and side effects present real barriers (Dooley et al., 2024).

What This Means for Mold Inspections

Regardless of where one lands on the diagnostic debate, the CIRS framework raises legitimate questions about inspection standards for patients presenting with complex, multi-system illness in a potentially contaminated building. A standard visual assessment and bulk sampling is not sufficient in that context. The investigation should answer:

• Where is the moisture source? Persistent mold communities require persistent water activity — finding and eliminating the moisture pathway is foundational.

• What is the species composition? Not all molds carry the same biotoxin burden. ERMI and qPCR-based testing identifies whether dominant genera are CIRS-relevant (e.g., Stachybotrys, Chaetomium, Aspergillus penicilloides, Wallemia).

• What is the total aerosolized burden? Air sampling assesses whether HVAC systems or disturbed materials are actively redistributing spores into occupied zones.

• Has remediation been verified? Post-remediation clearance via ERMI should be part of any remediation contract where a health-sensitive occupant is involved.

At MD Mold, we work with clinicians and CIRS-treating practitioners to produce inspection reports that include species-resolved qPCR data, moisture mapping, and remediation scope language meeting clinical clearance standards. A mold inspection in a health-sensitive context is not a commodity service — it is a detailed environmental investigation.

The Legal and Regulatory Landscape

CIRS has achieved limited but notable legal recognition. In 2021, a Florida court awarded a 56-year-old woman $48 million after she became disabled following prolonged mold exposure in her apartment and was diagnosed with CIRS (cited in Dooley et al., 2024). This represents one of the most significant biotoxin-illness civil verdicts in U.S. legal history, though it reflects a civil jury decision rather than a medical or regulatory endorsement of the diagnosis.

From a public health standpoint, Healthy People 2030 includes objectives for reducing harmful pollutants in homes and workplaces, with mold cited as a contributing factor to poor housing quality as a social determinant of health. The WHO’s Guidelines for Indoor Air Quality: Dampness and Mould (2009) also document health risks from WDB exposure, though the WHO framework does not use the CIRS nomenclature.

Conclusion: Mold, Buildings, and Human Health

The CIRS framework presents a biologically coherent model for how water-damaged buildings may produce chronic illness in genetically susceptible individuals. The clinical literature produced within this community — while contested and not yet accepted by mainstream medicine — points to real questions about the downstream health consequences of building moisture failures that extend beyond respiratory allergy.

If you or a family member has experienced unexplained multi-system illness — particularly symptoms that improve when away from a specific building and worsen upon return — professional mold inspection with qPCR-based species analysis is a reasonable environmental investigation step, and a mold-literate clinician can help evaluate whether CIRS workup is warranted.

MD Mold provides building science consulting, qPCR laboratory services, and IICRC S520-aligned remediation scope documentation for clients and clinicians navigating complex environmental investigations across Wisconsin and the Upper Midwest.

References

1. Dooley M, Vukelic A, Jim L. Chronic inflammatory response syndrome: a review of the evidence of clinical efficacy of treatment. Ann Med Surg (Lond). 2024 Nov 8;86(12):7248–7254. doi:10.1097/MS9.0000000000002718. PMC11623837. [Note: Authors disclose expert witness roles in CIRS litigation.]

2. Dorninger E. The CIRS Protocol: A Sequential, Evidence-Based Treatment for Biotoxin-Associated Chronic Inflammatory Response Syndrome. Medical Research Archives. 2025;13(8). doi:10.18103/mra.v13i8.6770. [Review article; author is ND/LAc, not MD.]

3. Shoemaker RC, Johnson K, Jim L, et al. Diagnostic process for chronic inflammatory response syndrome (CIRS): a consensus statement report of the consensus committee of surviving mold. Int Med Rev. 2018;4:1–47.

4. Rao TR, Sravya G, Kaushik T, Akshaya D. Chronic Inflammatory Response Syndrome (CIRS): A Review of Diagnosis, Immunological Mechanisms and Treatment Challenges. Int J Curr Sci Res Rev. 2025;8(7):3228–3230.

5. McMahon SW. An Evaluation of Alternate Means to Diagnose Chronic Inflammatory Response Syndrome and Determine Prevalence. Medical Research Archives. 2017;5(3). doi:10.18103/mra.v5i3.1125.

6. Shoemaker RC, House D, Ryan JC. Structural brain abnormalities in patients with inflammatory illness acquired following exposure to water-damaged buildings: a volumetric MRI study using NeuroQuant®. Neurotoxicol Teratol. 2014;45:18–26. doi:10.1016/j.ntt.2014.06.004. PMID:24946038.

7. Ryan JC, Qingzhong W, Shoemaker RC. Transcriptomic signatures in whole blood of patients who acquire a chronic inflammatory response syndrome (CIRS) following an exposure to the marine toxin ciguatoxin. BMC Medical Genomics. 2015;8(15). doi:10.1186/s12920-015-0089-x.

8. Berndtson K. Chronic Inflammatory Response Syndrome: Overview, Diagnosis, and Treatment. SurvivingMold.com. 2013. [Source of the 75% WDB estimate attributed to Shoemaker.]

9. U.S. Government Accountability Office. GAO-08-980: Indoor Mold: Better Coordination of Research on Health Effects and More Consistent Guidance Would Improve Federal Efforts. Washington, DC: GAO; 2008.

10. World Health Organization. WHO Guidelines for Indoor Air Quality: Dampness and Mould. Geneva: WHO; 2009.

11. AmeriHealth Caritas Ohio. Clinical Policy CCP.1371: Chronic Inflammatory Response Syndrome. December 2024 review. [Insurer coverage denial citing lack of ICD code and insufficient evidence base.]

12. UCLA Health. CIRS not considered an established medical diagnosis. Published December 2025.

Disclaimer: This article is intended for educational purposes and does not constitute medical advice. CIRS diagnosis and treatment should be managed by a qualified healthcare provider. Readers should be aware that CIRS is not a mainstream recognized diagnosis and that the clinical literature supporting it originates primarily from within a specific advocacy and practitioner community.

© 2026 MD Mold. All rights reserved.