[Update as of March 25 2020: A lot has changed since this was posted several weeks ago. The COVID-19 pandemic has resulted in an impressive rallying of scientific resources at a pace unimaginable only a few years ago. Hope for effective treatments soon is not unrealistic, but these will come from biotechnology. While it remains true that resveratrol has efficacy against corona viruses, the levels in wine are generally lower than what is used in laboratory tests of viral replication, and it has limited bioavailability. In my book I describe the scientific process in terms of the “skeptic’s checklist.” This situation may be a prime example; in vitro analyses and epidemiologic patterns suggesting that wine should be somewhat protective turn out differently when subjected to the ultimate test. But we don’t really know, even as cases mount in European countries known for their wine consumption. The percentage of symptomatic people testing negative for COVID remains high, while the number of minimally symptomatic people is also substantial. A very large percentage of those exposed will fight the virus off. Wine’s role in this is impossible to know; the observation that large absolute numbers of deaths from COVID-19 in countries with high per capita wine consumption neither proves nor disproves the premise that wine is helpful.]
Am I really going to suggest that wine is an effective strategy against the corona virus outbreak? Not quite, but there is evidence to suggest that red wine and compounds derived from wine are potent antivirals. Resveratrol, a polyphenol from red wine, has been shown to inhibit replication of the MERS-CoV (Middle Eastern Respiratory Syndrome) corona virus, and its predecessor SARS-CoV, both close relatives of COVID-19. These in vitro studies showed that resveratrol blocks expression of a protein essential for virus replication, resulting in prolonged survival of cells after being infected. While there are as yet no clinical studies on red wine compounds and corona viruses specifically, there is data correlating wine consumption with lower incidence of the common cold, much of which is caused by other corona-type viruses. Remember the H1N1 flu epidemic from a few years ago? Possibly not, if you were a wine drinker; wine-derived compounds are potent inhibitors of a variety of flu viruses too, including that nasty bugger.
Wine has broad spectrum antiviral activity
The antiviral effects of resveratrol and other wine compounds have been widely studied in a number of viruses which include hepatitis C virus, respiratory syncytial virus, varicella zoster virus, Epstein-Barr virus, herpes simplex virus, African swine fever virus, and even human immunodeficiency virus.,, The wine compounds delphinidin and epigallocatechin gallate inhibit the mosquito-borne West Nile Virus, Zika Virus, and Dengue Virus. Quercetin, another famous flavonoid from wine, has its own antiviral repertoire. Why wine should have such broad-reaching efficacy is not really so hard to explain if we consider that wine polyphenols are phytoalexins, substances produced by plants to fend off environmental stressors. These include viruses, and plant viruses are often similar to those that cause illness in animals. That’s why those in the know say you should eat stressed plants if you want to stay healthy.
So what is the best strategy to stay healthy during a viral epidemic? Wash your hands, stay home if you are sick, and if you haven’t already, get a flu shot. And to hedge your bet further, drink some wine; preferably red, and a little bit every day.
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