This is about something unpleasant which I never heard of before this month, but I am sharing in case readers may benefit from a bit of intel here.

In a family I know with two kids under five, it started with the youngest child after he was likely exposed to unclean water. He vomited once, and then was apparently fine. I may be a bit fuzzy on the timeline, but I think it was the next day that the father came down with symptoms. Besides violent emptying of the GI tract from both ends, he was flat in bed for over 24 hours, hardly able to move. This was initially blamed on food poisoning from a restaurant seafood meal, but by the following day, the mom was feeling weak and shortly succumbed, with similar effects.

A woman went over to help this family. She wore a N-95 type mask and washed her hands diligently. Within a few days, the full symptoms suddenly overtook her, as well.  But her husband never got it.  The older child in the original family seemed to have escaped, but a couple of days later he came down with similar symptoms, which lasted off and on for several days.

Most likely the culprit here was the “norovirus”. The virus is named after the city of Norwalk, Ohio, where an outbreak occurred in 1968. It bears the charming nickname, “the winter vomiting disease.” Although the effects of the virus are very unpleasant, fortunately they usually last only a couple of days, with full recovery being the norm.  The sufferer should acquire immunity to that strain of the virus for six months to two years. Some people may escape becoming symptomatic, based on the bacterial populations in their gut biome.

Since this is an economics blog, here are some quick stats. In the U.S. the norovirus is estimated to cause about 20 million illnesses a year and about half of all foodborne disease outbreaks. Norovirus causes some 900 deaths and 100,000 hospitalizations annually, mostly among adults aged 65 and older. It also leads to nearly 500,000 emergency department visits, mostly involving young children.

 A model of the worldwide economic burden of the disease found:

Globally, norovirus resulted in a total of $4.2 billion (95% UI: $3.2–5.7 billion) in direct health system costs and $60.3 billion (95% UI: $44.4–83.4 billion) in societal costs per year. Disease amongst children <5 years cost society $39.8 billion, compared to $20.4 billion for all other age groups combined. Costs per norovirus illness varied by both region and age and was highest among adults ≥55 years. Productivity losses represented 84–99% of total costs varying by region. While low and middle income countries and high income countries had similar disease incidence (10,148 vs. 9,935 illness per 100,000 persons), high income countries generated 62% of global health system costs.

Once it shows up in a family, it is hard to avoid. A reason is that you can be sickened by exposure to as few as ten viral particles, compared to billions that are expelled in a bodily fluid incidents. A doctor reported:

She once acquired a norovirus infection by simply using the same bathroom that had been used earlier in the day by a visiting in-law who was recovering from a recent bout with the stomach bug.  That’s because “people who have norovirus can shed the virus for up to two weeks after their symptoms are gone.”

In another case, a diner in a restaurant vomited on the floor. The mess was quickly cleaned up by staff, and other diners continued eating. In the next few days, 90% of the people at the same table as the sick person fell ill, along with 70% of the diners at an adjacent table, and 25% of the folks at a table across the room.

OK, that’s the bad news. How can we fight back? Lengthy handwashing with soap should help, along with quarantining as much as possible. It turns out that alcohol is not very good at killing this bug, so the usual hand sanitizers may be ineffective.  Better results can be had cleaning surfaces with a bleach-water solution.

The main care needed is hydration. From what I have read, most Gatorade-type sports drinks do provide needed electrolytes (e.g., sodium and potassium), but probably have more sugar that is optimal for this situation. Gatorade Zero has sucralose in place of sugar, if you are OK with that. Pedialyte is designed for rehydration after diarrhea, and has less sugar and more electrolytes than Gatorade. Avoid “Gatorade Water” – it is just water, with the tiniest “infusion” of sodium and potassium.

If you find yourself stricken, it is reportedly wise to have a wastebasket or other receptable at hand in the bathroom, in case you face urgent activity from both ends at once (trying to word this delicately).

Fun fact I learned researching this topic: if the GI tract has been emptied, best avoid dairy for 48 hours after symptoms stop. That allows lactose in the gut to build back up again.

I have never gone on an extended cruise, partly because I don’t think I could resist the frequent offerings of desserts and snacks. But reading of norovirus outbreaks on cruise ships has given me another reason to stay on terra firma.