Thursday, 10 January 2013
Norovirus – running to a bathroom near you
Its that winter stomach bug. Hits like a truck with waves of nausea, heaving gut, urgent and frequent trips to the toilet. We’ve all experienced it, and likely blamed bad food or that sick co-worker.
Fortunately most of us recover in a couple of days. It can be problematic for the medically fragile, but even among the sensitive an amazing number recover compared to its influenza cousin.
As a virus, it is highly efficient in its spread. It undertakes just enough genetic drifting that every few years there is increased disease activity due to greater pathogenicity. This year, we are welcoming the GII.2 Sydney (2012) strain.
When it hits about one in ten of us will suffer a bout, about six thousand Canadians will be hospitalized and fortunately fatalities are perhaps under a hundred. Actually, we really don’t know since surveillance systems are not robust for tracking the impacts of norovirus. Estimates are based on some good US work in the 2004-05 years EID August 2011 Norovirus . Canada estimates some 300-400 outbreaks each year, although only those in long term care settings are routinely reported from most provinces. Surveillance for what is seen as an annoyance is never good, but the cost of nosocomial outbreaks, clean up in the hospitality industry, lost wages and other indirect costs must run in the billions annually (but if you are aware of any, please send any economic analysis so this can be updated). There are some nascent efforts on improving surveillance systems EID 2011 surveillance
Norovirus developed its fame as the cruise ship illness. Put a large number of people in a confined space, and lo and behold a high proportion of them got sick. The more you look, the more Norovirus can be implicated. National Parks in Canada and the US routinely have norovirus outbreaks during summer holiday season. so those campground runs might just as well have been from Norovirus as from the undercooked hamburger.
Beyond the frequent trips to the bathroom, the annoying thing about Norovirus is its propensity to spread to the unsuspected as the virus survives well outside the body. Over half a day on hard surfaces like door knobs, telephones, shopping carts. On more comfortable surfaces like cushy chairs, it may survive for longer than a week.
There is no magical prevention like a vaccine, vitamins or natural products that are known to make a difference. Immaculate personal hygiene with constant handwashing and use of hand sanitizers will reduce your chances of getting struck. Find a bit more at PHAC info sheet
Good luck, and keep some good reading material in the bathroom just in case.