Proponents of chlorine dioxide solution (CDS), led by biophysicist Andreas Kalcker, assert its remarkable efficacy against viral infections, including COVID-19. Kalcker’s claims rely heavily on anecdotal testimonials and observational reports, particularly from Bolivia, where CDS gained temporary legitimacy during the pandemic. He cites a controversial study by the Global Coalition for Health and Life (COMUSAV), which reported a 99.3% recovery rate in 1,136 COVID-19 patients treated with CDS . This data, however, originates from non-peer-reviewed sources and lacks rigorous controlled conditions.

Kalcker also references in vitro studies suggesting chlorine dioxide disrupts viral envelopes and proteins, potentially inhibiting pathogens like SARS-CoV-2. His 2025 review in the International Journal of Multidisciplinary Research and Analysis argues that CDS’s selective oxidation mechanism targets viruses without harming human cells at low concentrations (≤50 ppm) . Additionally, he points to historical uses of chlorine dioxide in water disinfection and blood bag sterilization as indirect evidence of its antiviral properties .

Despite these assertions, mainstream science remains skeptical. Health authorities—including the FDA, WHO, and Bolivia’s own health ministry—have warned against CDS consumption, citing risks like liver failure, severe dehydration, and methemoglobinemia . A 2023 scoping review found no conclusive clinical evidence supporting CDS for COVID-19 or other viral diseases, highlighting that most pro-CDS studies suffer from methodological bias or conflate CDS with more toxic variants like MMS .

The Bolivian case exemplifies this divide: while political figures and grassroots movements promoted CDS as a "miracle cure," hospitals reported hospitalizations from chlorine dioxide poisoning, including esophageal lesions and fatal outcomes . Kalcker attributes these incidents to misuse or excessive dosing, arguing that properly administered CDS is safe .

Ultimately, the controversy underscores a critical gap: the absence of large-scale, randomized controlled trials. Until such evidence emerges, CDS remains a polarizing subject—hailed by some as a breakthrough and dismissed by others as dangerous pseudoscience. For now, the scientific consensus urges caution, emphasizing that testimonials are no substitute for validation.

Proponents of chlorine dioxide solution (CDS), led by biophysicist Andreas Kalcker, assert its remarkable efficacy against viral infections, including COVID-19. Kalcker’s claims rely heavily on anecdotal testimonials and observational reports, particularly from Bolivia, where CDS gained temporary legitimacy during the pandemic. He cites a controversial study by the Global Coalition for Health and Life (COMUSAV), which reported a 99.3% recovery rate in 1,136 COVID-19 patients treated with CDS . This data, however, originates from non-peer-reviewed sources and lacks rigorous controlled conditions.

Kalcker also references in vitro studies suggesting chlorine dioxide disrupts viral envelopes and proteins, potentially inhibiting pathogens like SARS-CoV-2. His 2025 review in the International Journal of Multidisciplinary Research and Analysis argues that CDS’s selective oxidation mechanism targets viruses without harming human cells at low concentrations (≤50 ppm) . Additionally, he points to historical uses of chlorine dioxide in water disinfection and blood bag sterilization as indirect evidence of its antiviral properties .

Despite these assertions, mainstream science remains skeptical. Health authorities—including the FDA, WHO, and Bolivia’s own health ministry—have warned against CDS consumption, citing risks like liver failure, severe dehydration, and methemoglobinemia . A 2023 scoping review found no conclusive clinical evidence supporting CDS for COVID-19 or other viral diseases, highlighting that most pro-CDS studies suffer from methodological bias or conflate CDS with more toxic variants like MMS .

The Bolivian case exemplifies this divide: while political figures and grassroots movements promoted CDS as a "miracle cure," hospitals reported hospitalizations from chlorine dioxide poisoning, including esophageal lesions and fatal outcomes . Kalcker attributes these incidents to misuse or excessive dosing, arguing that properly administered CDS is safe .

Ultimately, the controversy underscores a critical gap: the absence of large-scale, randomized controlled trials. Until such evidence emerges, CDS remains a polarizing subject—hailed by some as a breakthrough and dismissed by others as dangerous pseudoscience. For now, the scientific consensus urges caution, emphasizing that testimonials are no substitute for validation.