About the Author

Andy Wilcox is an independent researcher who has spent more than 30 years applying rigorous analytical methods to complex primary-source material. He is the founder of the Virus Questions network — a group of evidence-based public health information sites covering individual viral diseases.

Andy is not a physician, virologist, or epidemiologist. His background is in analytical research — the discipline of synthesizing large volumes of primary-source material into clear, accurate, and accessible conclusions. He applies that same discipline to public health information, working directly from CDC, WHO, NIH, and peer-reviewed sources rather than secondary summaries.

Why norovirus

Norovirus is, for an analyst, the most interesting virus in the network: the largest numbers and the least certainty. It causes an estimated 19–21 million US illnesses a year, more than any other virus this network covers — and not one of those illnesses is counted. Norovirus is not individually reportable; the CDC's figures for illnesses, hospitalizations, and deaths are all modeled estimates with confidence intervals that its consumer pages omit. The gap between "the leading cause of foodborne illness in America" and "a disease nobody counts" is exactly the kind of gap that rewards reading the underlying studies rather than the summary. That is what this site tries to do.

How this site is researched

Every clinical page on NorovirusQuestions.com is written from primary sources read directly, and the practice is specific enough to describe:

• CDC pages are read in full, in a browser, and dated. Each citation records the page's own "last updated" date, because CDC pages change and a claim that was accurate against the April 2024 version may not be against a later one.
• Regulations are read from the regulator's document, by section. The food-worker exclusion rules on the Food Safety page are quoted from Chapter 2 of the FDA Food Code 2022 PDF, with section numbers, not from a training summary.
• Peer-reviewed claims carry a DOI, and the abstract is read on PubMed before the paper is cited. Where two good studies disagree — as they do on norovirus's infectious dose — both are cited and the disagreement is explained.
• Live surveillance is checked, not assumed. CDC's CaliciNet genotype table and NoroSTAT outbreak counts update monthly; the figures on the Outbreaks page carry the date of the update they were taken from.
• Arithmetic is shown. When a percentage or a comparison on this site is our calculation from published figures (a share of CaliciNet outbreaks, an infectious-dose ratio), the inputs are given and the result is labeled as ours.
• Some numbers are deliberately not computed. A case-fatality rate built from two modeled estimates is a false precision; the Risk Perspective page leaves it blank and says why.

Pages are also reviewed monthly by an automated process that checks each factual claim against the current versions of the cited sources and flags contradictions for human review; the "Last reviewed" date on each page reflects the most recent review. Automated review cannot re-derive a figure from a study, so the substantive research above is done by hand.

What a research background does and does not qualify me to say

Thirty years of verifying other people's claims — in due diligence, operating businesses, and investing — is good training for reading a CDC page against the study it summarizes, noticing when a "65%" has no source, or catching that a cited PubMed ID points to the wrong paper. All three of those happened on this site and are recorded on the corrections page. It is not training for clinical judgement. Nothing here can tell you whether your symptoms, your exposure, or your child's dehydration warrants care; a healthcare provider can. The computed record below shows what this site has actually checked, corrected, and left blank.

The Virus Questions Network

NorovirusQuestions.com is part of the Virus Questions network, which includes:

• VirusQuestions.com — Network hub
• CoronavirusQuestions.com — COVID-19
• EbolaQuestions.com — Ebola
• HantavirusQuestions.com — Hantavirus
• NorovirusQuestions.com — Norovirus (this site)

Contact

To submit a question, report a factual error, or request a correction, use the Contact page or the Corrections page.