Earlier this year, I wrote about an outbreak of norovirus in a US car dealership. There, the outbreak was traced to a toddler “spraying” norovirus around a public restroom and baby-changing station. Regrettably, I now have my own experience to relate.
Last Wednesday (let’s call it outbreak day 1), our 18-month old toddler “sprayed” projective vomit around our porch. My wife cleaned up the mess (not with dry paper towels, as in the US car dealership outbreak but with detergent and water). On outbreak day 3, 36 hours later, my wife presented (grumpily) with acute gastroenteritis. We made every effort to limit domestic horizontal transmission (including regular bleach disinfection of contact surfaces in the bathroom and cohorting of personal effects) but to no avail; a little over 24 hours later on outbreak day 4, I endured acute gastroenteritis.
What do we learn from this?
- Transmission routes for viral gastroenteritis are very difficult to disentangle. It seems likely that my wife acquired norovirus whilst cleaning up the vomit, and I acquired norovirus from my wife somehow. Of course, this may not have been the case. My wife could have acquired the infective agent in a number of ways from our toddler. Also, I could have acquired it directly from our toddler and not my wife. Finally, a common source seems unlikely due to the ‘domino’ type progression, but cannot be discounted. If I can’t be sure of transmission routes amongst three people in a single household, how can we hope to understand transmission routes on a hospital ward or aboard a cruise ship
- We are not sure what caused the outbreak. None of us were in the mood to submit a specimen during the outbreak and, even if we had bothered to collect one, how would we have got it analysed? Take it to the GP (bad idea) or hospital lab (even worse) or post it (unhappy mail carrier). Thus, our understanding of the prevalence and aetiology of gastroenteritis in the community is woefully lacking.
- It’s been expensive. I was unable to travel to mainland Europe for an important meeting last week due to this outbreak, which has meant re-booking the trip at expensive short notice. Plus, I am still unable to go to work today (since I’m still within 48 hours of my symptoms). Whilst I am fortunate in that my work can be conducted from home, others are not so lucky. I suspect that the economic impact of viral gastroenteritis is hugely underestimated. In fact, I am not sure anybody has really tried to estimate it, let alone underestimate it, due to the lack of meaningful prevalence data.
- Horizontal transmission is difficult to block. We took every precaution that we could think of to prevent horizontal transmission, without success. Part of the problem was that we did not recognise the outbreak immediately. This principle translates to preventing horizontal transmission in hospitals: the pre-diagnosis management of patients with diarrhoea and vomiting is crucial.
- It’s very, very unpleasant. We are a young, (fairly) healthy family and each of us were laid out for 12 hours, and pretty useless for at least 24 hours. I can see how somebody who is already unwell and in hospital would be affected very badly indeed. I recommend that anybody who cares for patients in hospitals with acute gastroenteritis should be sure to try it themselves, in the interests of empathy.
Could we have done a better job of preventing the spread of this acute bout of gastroenteritis through the Otter household? Probably, through better outbreak identification and more stringent cohorting (perhaps with universal gowns and gloves, and liberal use of masks). But really, I’m just counting our blessings that we didn’t all get it at the same time.
Reflections on Infection Prevention and Control 
Ahhh….the joys of acute GI rumblings!! Sorry Jon and I’m glad you and the family are on the mend. A couple of quick comments that come to mind from your “experience” and how it relates to the epidemiology and to the real-world issues of outbreaks. First, let’s be sure to mention that there are so many agents that cause these types of GI illness that one can not be sure it was norovirus that you and your family acquired. I know that most of us know this, but for those reading this blog who don’t…there are dozens and dozens of viral (and other microbes) that can cause acute GI illness (including food intoxication, like Staphylococcus aureus, versus a true infection, like Salmonellosis). It goes without saying that the collection of specimens with follow-up standard microbiological identification and susceptibility testing would be the order of the day (even though, as you mention, in most cases this is realistically impossible).
Secondly, it’s also important to remind readers that projectile vomit, cleaning up after the toddler, fomite transmission, etc. may have played a role in your family transmission chain. Yet, as you state, that’s very difficult to know. For example, perhaps your wife acquired the illness even before the toddler’s unfortunate event on the porch via aerosol droplet. Your toddler may have well been in the incubation stage of the illness and she acquired it (and perhaps you too) when you didn’t even know the toddler was sick and transmitting. My point here is not to belabor the point of how this started. My point is to echo your comments. Stopping the chain of transmission of these viral (or other microbes) agents is near impossible once they get cooking in the environment and especially when you have a pool of naïve hosts ready to become incubators for these agents.
Finally, I think these types of discussions are very important for the general, lay public to read. It is extremely easy for these events to occur and we all should be suspicious of unclean environments and how we go about our daily hygiene. We do not have to be germaphobes, but we do need to be wary of situations that merit our attention. Remind coworkers to not come to work if they exhibit fever and other acute signs and symptoms. Remind your healthcare colleagues that we are only as good as our own advice – use sound preventative measures when treating patients.
I hope the Otter family is back on track. Perhaps we should all discuss an “at home” or “at work” event in the future with respect to our own experiences with an outbreak. We just might do something crazy – help transmit knowledge of public health and prevention measures! Feel better Otters….
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Thanks Rodney for your insightful comments. You’ll be pleased to know we’re all right as rain today. I feel sure that it was norovirus. The 100% attack rate, staggered transmission, rapid onset, acute gastroenteritis (including both diarrhoea and vomiting) and short duration are together very much characteristic of norovirus. I can’t think of another GI pathogen that would present in this way.
I agree that we shouldn’t become ‘germophobes’ – we’re surrounded by microbes of most of them are friendly and helpful. The Prof Sally Bloomfield and colleagues at IFH has coined a useful approach of a ‘targeted approach to home hygiene’ with this in mind, which you may find interesting: http://www.ifh-homehygiene.org/review/chain-infection-transmission-home-and-everyday-life-settings-and-role-hygiene-reducing-risk.
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Jon,
I am sorry about your personal situation.
Your personal encounter and story depicts the nature and difficulty in preventing the spread of pathogens, not only in facilities, but schools, businesses, literally any where people congregate…
This scenario is played out hundreds of times with different viral and bacterial causes.
Pathogens truly are everywhere, they are on everything, they are airborne permanently suspended as Droplet Nuculi, they can be spread through a variety of circumstances.
We must take a layered approach, addressing all modes of transmission, in our efforts to deal with the spread of pathogens.
Good Luck., both to you and your family.
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Thanks Scott. Agree that a multifaceted approach is required. There’s some epidemiological evidence for airborne spread of norovirus, such as this: http://www.ncbi.nlm.nih.gov/pubmed/12948373. However, there is a paucity of data on this issue in particular due to difficulties in culturing norovirus itself. We know that vomiting and diarrhoea results in microbial aerosols, so we do need to address airborne spread of norovirus. Recently published UK guidance on respiratory and facial protection consider norovirus as a droplet-spread pathogen and recommend the use of a surgical mask only in the event of a spillage / risk of splashing: http://www.journalofhospitalinfection.com/article/S0195-6701(13)00279-X/fulltext.
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Jon,
Glad to hear you are all on the mend. Unfortunately we all have encountered the norovirus experience. This is the perfect time to ask what were the surfaces that were affected and needed to be cleaned? I think the porcelain found in the bathroom clearly is one and thankfully it is fairly easy to clean. one that is fairly easy to clean. What is not considered or rarely thought about are the other surfaces. Hardwood floors, carpet, laminate,a variety of fabrics found in a home. High touch surfaces and in this case surfaces that are in the direct path of projection.
Even in an extremely clean home one can not be sure where pathogens may have landed or how much remained creating a location of potential contamination. Clearly we need to investigate how much bio load needs to exist before cross contamination effectively occurs.
I concur we don’t need to be germophobes, and we certainly don’t need to change surfaces within our homes to ensure a porcelain like finish. I just wanted to point out that some surface may have contributed to the spread of the illness within your house. In some situations no matter how much disinfection and bleach is used not all surfaces can be cleaned completely.
Those of us that are able to fight off illness fairly easily are fortunate.
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Interesting that you should mention this. The porch has a concrete floor covered with mats. Frankly, it is probably not possible to remove norovirus from either!
In terms of infectious dose for norovirus, it is generally considered to be very low indeed. Even 1 virus particle may be enough to initiate infection: http://link.springer.com/article/10.1007%2Fs12560-011-9056-7.
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Schools, playgroups, and child contact undoubtedly introduce viruses into families and constitute a non-immune institutional spread environment where viruses and bacteria rapidly spread. Some spread is a predictable event. Strep pyogenes in primary schools in the under 10s in October and February when new classes assemble and attack rates can be as high as 40%. Others such as noro are unpredictable. It is very difficult to separate out contact hand-oral and respiratory spread with high infectivity agents. Secretion splatter in someone who has vomited or sneezed or been incontinent goes much wider than we think even without the issue of droplet nuclei in true aerosols. The reality of clearing up is that cleaning up may merely redistribute pathogens e.g. detergent and C difficile, and inactivation can be difficult in the presence of organic matter. Gloves and hand hygiene are almost unavoidable control measures in the home and school as much as in hospital but no-one says this – preferring to promote disinfection. The potential marketing of “spillage kits” comes to mind for domestic use rather than relying on ad hoc material!
hand hygiene is possible if disinfection of surfaces is not and with avoidance of cuddles with kids seems to keep one free of some acquisition from the environment. I wonder if anyone has ever looked at liquid soap and palm-oil products in the home as dispersants rather than inactivators. Many of course are not soaps or detergents but based on palm oil about which I know nothing. Peter Hawkey in Birmingham and Liz Wellington at Warwick have pointed out that most fabric softeners contain very large quantities of Quaternary ammonium compounds which probably have bacterial but not viral effects. Detergents of course would probably be effective against enveloped viruses such as noro/rota but these do not get used as much as we might think.
Incidentally PCR in the environment is entirely possible with noro and has been used investigatively in the ward environment – contamination was widespread in wards with outbreaks particularly if there had been vomiting as distinct from diarrhoea on the ward. A quantitative PCR might offer insights if not confounded by DNA from inactivated virus.
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Agree that introduction and spread is to a fairly large degree unavoidable in settings where you need to have close contact with children in the home, or patients in the hospital.
Eliminating the environmental reservoir in both hospital and home environments has proven very difficult for norovirus, as judged by this study, which uses quantitative real-time PCR to evaluate norovirus environmental disinfection: http://www.ncbi.nlm.nih.gov/pubmed/21167622
So perhaps your proposed focus on glove use and hand hygiene should be the target of our prevention strategy in both hospital and home settings? The nagging doubt is: what good is exquisite hand hygiene compliance when you are surrounded by surfaces contaminated with a low infectious dose, highly transmissible pathogens? This argues for a multifaceted approach.
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Bad news Norovirus. It is difficult to hear about others having it particularly children. People should only know how incredibly disabling this virus can be. A handful of years ago I watched the virus march through one of our hospital units. In retrospect I am ever so grateful it was in a small closed unit and I am so grateful to this day a hospital VP agreed with me to immediately close the unit down even tighter. The rest of the story is too long to explain here. About 2 years after the departmental experience I got sick as a dog. For whatever reason the physician sent out a fluid sample & it was confirmed as Norovirus. Imagine my surprise as I was the only one who was sick; I worked in a hospital with multitudes of exposure opportunities. It turns out I ate the virus from take-out food. (It’s sickening to know how it got in my food.) Even though my husband ate food from the same place on the same night he did not get sick. I remember asking if God would please end my life because by the 3rd day I couldn’t take the bodily explosions anymore. I ended up in the hospital for IVs with potassium & for IM anti-emetics. Even so I think the disease ran it’s course so I did get better and I did ask God to please forget my previous request. What was I proud of? My husband who was with me the entire time & my out-of-town sister who picked the wrong days to visit, did not get sick. Noro is a very serious viral illness, I wouldn’t wish it on anyone.
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Sorry to hear of your experience Jo and thanks for taking the time to relate it. Delighted to hear that you managed to prevent transmission to your husband and sister. Can you put your finger on why the virus did not spread to them?
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Sorry to hear about this unfortunate domestic outbreak I hope you and your family are now back in good health. You do make a good point about the difficulty of tracking this type of infection. Airborne transmission of Noro virus from projectile vomit has been studied and particles shown to travel in excess of 3 metres. Viruses can remain on surfaces not disinfected and are still able to cause infection if transferred by hands to the mouth. Controlling this on a large scale is a major problem.
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