ArticleProceedings of the National Academy of Sciences of the United States of America2021
The hygiene hypothesis, the COVID pandemic, and consequences for the human microbiome.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. An erratum has been issued. Cited by 96 papers, 1 of them a synthesis that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
96 citing papers in PubMed, 1 synthesis or guideline pooled it, 167 citations in OpenAlex.
- Impact of SARS-CoV-2 Vaccination or Infection on the Safety and Efficacy of Aesthetic Injections: A Systematic Review.Aesthetic plastic surgery · 2024Pooled it
- Alteration of the Gut-Lung Axis After Severe COVID-19 Infection and Modulation Through Probiotics: A Randomized, Controlled Pilot Study.Nutrients · 2024Trial
- The Effect of Oral Iron Supplementation on Gut Microbial Composition: a Secondary Analysis of a Double-Blind, Randomized Controlled Trial among Cambodian Women of Reproductive Age.Microbiology spectrum · 2023Trial
- Review
- Incidence rates of allergy diagnoses in the U.S. military health system after the COVID-19 pandemic.Frontiers in allergy · 2026Article
- The ethnicity and gut microbiota hypothesis: analyzing multifactorial interactions and their health implications.Frontiers in microbiology · 2026Review
- Attention-deficit/hyperactivity disorder in India: epidemiology, diagnostic inequities, treatment gaps, and public mental health implications.Frontiers in psychiatry · 2026Review
- Changes in Healthy Infant Gut Microbiota over the Past Decades.Neonatology · 2026Article
- Haemophilus influenzae and Staphylococcus aureus population shifts during social distancing as monitored by MALDI-TOF MS.Scientific reports · 2025Article
- Impacts of COVID-19 pandemic on early life gut microbiome.Gut microbes · 2025Article
- Impact of shared spaces and daily routines on shared microbiome.Scientific reports · 2025Article
- Increased Risk of Type 1 Diabetes in Boys Under the Age of 5 Years During COVID-19 Lockdowns in Finland, Sweden and Stanford, CA, USA-An Observational Multicenter Study.Diabetes/metabolism research and reviews · 2025Observational
- Social Microbial Transmission in a Solitary Mammal.Ecology letters · 2025Article
- Early development and dynamics of nasopharyngeal microbiota in infants during the COVID-19 pandemic: a 2-year prospective birth cohort study.Respiratory research · 2025Article
- Intestinal Microbiota in Early Life: Latest Findings Regarding the Role of Probiotics as a Treatment Approach for Dysbiosis.Nutrients · 2025Review
- Quantification of Viruses in Wastewater on a Centrifugal Microfluidic Disc.Environmental science & technology · 2025Article
- New-Onset Type 1 and Type 2 Diabetes Among Korean Youths During the COVID-19 Pandemic.JAMA pediatrics · 2025Article
- Resilience to Global Health Challenges Through Nutritional Gut Microbiome Modulation.Nutrients · 2025Review
- Helminth infections affect host immune responses to viral infections and vaccines.FEMS microbiology reviews · 2025Review
- Shaping oral and intestinal microbiota and the immune system during the first 1,000 days of life.Frontiers in pediatrics · 2025Review
36 more citing papers are in PubMed but not listed here.
Corrections and comments
- Erratum issued
Authors and funding
23 authors at 2 institutions in 6 countries.
Funding
Abstract
The COVID-19 pandemic has the potential to affect the human microbiome in infected and uninfected individuals, having a substantial impact on human health over the long term. This pandemic intersects with a decades-long decline in microbial diversity and ancestral microbes due to hygiene, antibiotics, and urban living (the hygiene hypothesis). High-risk groups succumbing to COVID-19 include those with preexisting conditions, such as diabetes and obesity, which are also associated with microbiome abnormalities. Current pandemic control measures and practices will have broad, uneven, and potentially long-term effects for the human microbiome across the planet, given the implementation of physical separation, extensive hygiene, travel barriers, and other measures that influence overall microbial loss and inability for reinoculation. Although much remains uncertain or unknown about the virus and its consequences, implementing pandemic control practices could significantly affect the microbiome. In this Perspective, we explore many facets of COVID-19-induced societal changes and their possible effects on the microbiome, and discuss current and future challenges regarding the interplay between this pandemic and the microbiome. Recent recognition of the microbiome's influence on human health makes it critical to consider both how the microbiome, shaped by biosocial processes, affects susceptibility to the coronavirus and, conversely, how COVID-19 disease and prevention measures may affect the microbiome. This knowledge may prove key in prevention and treatment, and long-term biological and social outcomes of this pandemic.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.