Is Norwalk a "Class Disease"?

[Philip217]

If you go to the CDC Website and read the Vessel Outbreak Summary Reports, you can get all the details on all shipboard illness outbreaks reported to CDC from 1994 through 2008. An outbreak is defined as 3% or more of the souls onboard suffering from some illness.

 

200 outbreaks have been reported and investigated by CDC from 1994 through 2008. Most were found to be NLV.

 

Now try to find ships from the luxury lines reporting outbreaks.

--Crystal had a small outbreak in 2005, Cause was not determined.

--Silversea had 2 small outbreaks in 2004. Cause was not determined.

--ResidenSea had a small outbreak - crew only - in 2004.

--Seaborn had a small outbreak in 2002. Cause was not determined.

 

These are all small ships, where it takes far fewer cases of illness to make 3% of the total onboard. Yet still they had only 5 total outbreaks in 15 years. And one of those outbreaks was only crew - on a condo ship.

 

So we saw only 4 outbreaks affecting passengers on luxury cruise ships in 15 years time.

 

Are wealthy cruisers cleaner than mass market cruisers?

Do wealthy cruisers have better immune systems than mass market cruisers?

[rubytue]

Seriously?!

[Chigirlcruzin]

Are you kidding me??:eek: This has to be one of the most ridiculous questions I've ever seen!:eek:

 

No, wealthy people are not cleaner than than mass market cruisers, nor do they have better immune systems. In fact, since luxury cruisers are usually older, that have weaker immune systems.

 

I normally really enjoy your posts, but this one is insane:rolleyes::mad:

[navybankerteacher]

It's not the cruisers who are healthier, it's the ships. If you look at the staffing ratios per passenger, the upscale ships are much better staffed. This should logically translate to better maintenance, more regular cleaning, less crowding of passengers in all venues -- all of which should result in lower contagion levels. Just as the black death was less threatening to the aristocracy than to peasants in medieval times, shipboard illnesses today are less threatening to upscale passengers than to the mass market.

[Philip217]

I'm NOT proposing that wealthy cruisers are cleaner than mass market cruisers.

I'm NOT proposing that wealthy cruisers have better immune systems that mass market cruisers.

But I AM asking, "Why is there such a difference"?

I don't have an answer.

That's why I posted this on the "Ask a Cruise Question" page.

 

I have been asked on many occasions why it is that the luxury ships have far fewer outbreaks than mass market ships. The numbers reported by CDC certainly support that fact.

 

On a luxury cruise ship that carries 100 pax and 100 crew, a total of 6 passengers and crew need to get ill to qualify for an outbreak. You would think that this would happen very often. But it has only been recorded 4 times in 15 years.

 

The large mass market ship I work on has a minimum 20 or 30 sick with Norwalk every week of the year. These are normal baseline numbers for large ships.

 

On a mass market ship that carries 5000 crew and pax, it's not an outbreak until at least 150 are sick. But when you look at the summary reports, this happened 195 times from 1994 - 2008.

 

We know that 10% of the American population is suffering from NLV.

We know that the majority of cruise passengers are American.

We know that the majority of luxury line pasengers are American.

We know that the majority of mass market line passengers are American.

 

Having worked for some of the luxury lines, we used the same chemicals and cleaning procedures there that we use on the mass market lines.

Although there is more public space per pax on the luxury lines, passengers there are usually restricted to a single restaurant, only 1 or 2 bars, only a very few public toilets, only one or two elevators. In theory they would face higher chances of contamination when everyone must use the same facilities.

 

Although a luxury ship has a higher ratio of total crew to passengers, a mass market ship has a higher ratio of housekeeping crew to passengers. The housekeeping crew do most of the sanitizing. In theory, they should be able to do a better job on a mass market ship, with all the extra manpower to do the job. Once again, ALL the ships use the same chemicals and cleaning procedures.

 

So back to my original questions.

Why is it that the luxury lines have so few outbreaks compared to the mass market lines?

[Chigirlcruzin]

Navybankerteacher hit the nail on the head.

[dustyroad]

put this question in the trash bin where it belongs. and i agree that this is the most rediculous question i have ever read.

[Chigirlcruzin]

I'm NOT proposing that wealthy cruisers are cleaner than mass market cruisers.

I'm NOT proposing that wealthy cruisers have better immune systems that mass market cruisers.

 

 

Reread your OP. Yes, you did imply wealthy cruisers are cleaner and have stronger immune systems:rolleyes:

[agabbymama]

I do think OP has a point, and I don't find this a ridiculous query at all.'

When you have paid $2000-3000 for a cruise, who wants it ruined with a case of Norwalk?

 

Mass market cruises have become more affordable for families. If you check statistics, Noro virus hits daycare, schools just as much if not more than cruise ships. But there is no law mandating that they have to report it or keep statistics on it. Children are not as cleanly as adults. More children on a cruise ship holding 2000-3000 people is going to spread in an instant. Then add in the adults that wipe their behinds, don't wash their hands, then come out to the buffet line, and you a have a disaster waiting to happen.

 

I don't think you will see as many families on the luxury lines, therefore it is easier to advise the passengers & crew of proper procedures, even if an outbreak does occur, it would be easier to contain. JMO!

[ovccruiser]

 

We know that 10% of the American population is suffering from NLV.

We know that the majority of cruise passengers are American.

We know that the majority of luxury line pasengers are American.

We know that the majority of mass market line passengers are American.

 

So don't cruise with Americans:D Seriously, it may well be down to more staffe better cleaning regime, staff waiting in the restaurant to squirt the hand cleaner as you enter, and, I hate to pass any sort of blame, less children, boys in particular, generally not the cleanest. Most wouldn't even wash in the morning if was up to them :)

[Philip217]

agabbymama,

You might have the right answer - or not.

 

navybankerteacher and chigirlcruzin don't understand that large mass market ships have higher numbers - and percentages - of cleaning staff who use the same chemicals and cleaning procedures as the smaller ships. With the increased manpower for cleaning on the larger ships, they "should" be cleaner. But the number of outbreaks doesn't support that.

 

We do know that far fewer children and older/infirm passengers travel on luxury ships.

I'm not an authority on either of these two groups.

 

Could it be that the higher numbers of children and/or older people are the cause of increased Norwalk outbreaks on mass market ships?

This would appear to explain why Norwalk outbreaks on land frequently occur in schools and retirement homes.

[Peregrina651]

OP, have you read Freakonomics? I think you might enjoy it.

 

This is the kind of question that a statistician/economist might ask and investigate. He asks is there a correlation --not necessarily a causation-- between two observations.

 

So, let them laugh, but I think that you have made an interesting observation that might have more to do with preventing out breaks than it has to with issue of class and money.

 

 

 

[Chigirlcruzin]

OP, have you read Freakonomics? I think you might enjoy it.

 

This is the kind of question that a statistician/economist might ask and investigate. He asks is there a correlation --not necessarily a causation-- between two observations.

 

So, let them laugh, but I think that you have made an interesting observation that might have more to do with preventing out breaks than it has to with issue of class and money.

 

 

 

 

Interesting observation, yes. But the OP did make a causation assumption, which is assanine. I completely agree with your last statment.

[iancal]

I think it has more to do with the number of passengers on a ship, ship cleanliness, and quite frankly-stupid passengers. We have pretty much stopped going to the buffets. On our Westerdam trip last Feb, we watched an older gentleman paw through a plate of cookies at the ice cream area. He must have handled about ten before picking the three that he wanted. My spouse and I were having coffee nearby-that did it for us. And yes, there was a set of thongs right beside. Same thing on a Princess ship two years ago. Lady was pawing her way throught the pineapple and then the pan cake. This is how the disease spreads.

[dustyroad]

excuse me, but the op is the one that put the word '' class '' in his title. that is pretty insulting to me. :mad:

[Happy ks]

It always amazes me when people make comments regarding children and illness. It's not like they are walking germ-fests. I think they get sick more easily because they have not built up as much immunity as adults, not because their little hands and feet get dirty from playing. No need to fear them.

 

I think the true answer is that the luxury lines have fewer passengers, period. Less people means less possibility of someone coming onboard carrying an illness.

 

I also think the ships personnel can clean all they want, but as soon as an infected person touches that clean railing, elevator button, counter top at the Guest Relations desk, buffet ladle etc... it is covered in germs once again. Pity we can't see the little buggers.

 

No matter the economic status of any passenger, if they wander the ship when sick with a virus, they will share their illness. Same thing with head lice or a cold or any other communicable disease, it can't look into your bank account or see your passport to see if you are eligible for their infestation, germs both viral and bacterial don't care who you are.

[sail7seas]

I don't know if OP's supposition/pondering is correct or not.

What I'd like to know is a similar statistic to what he listed as percent of American popularion that has NLV.

 

What percent of Europeans have NLV?

What percent of Asians have NLV?

What percent of Australians have NLV?

What percent of Canadians have NLV?

Etc

 

Rather than a class distinction, I wonder if he is questioning a nationality distinction?

[Philip217]

sail7seas,

 

You can google Norwalk Virus and find some very interesting numbers on breakdown by nationality.

 

We already know that Norwalk Virus is more prevalent in North America and the UK than it is in many other parts of the world. Just as we know that Avian Flu is more prevalent in Asia, Malaria is more common in Southeast Asia, and HIV is more prevalent in Africa.

Who knows why, but that's what the numbers tell us.

 

Knowing that the overwhelming majority of cruisers comes from North America and the UK, it is hardly surprising that NLV is so common on cruise ships. The fact that more NLV outbreaks are seen on all ships sailing from North America, than on all ships sailing from most other continents is also not surprising.

 

The fact that cruise ships carrying primarily Germans, Italians, Chinese, Russians, or Japanese almost never have NLV outbreaks is also not a surprise. NLV is very rare in those countries, and so is rarely brought aboard by embarking passengers.

 

But what is perplexing is the fact that most cruise ships - luxury and mass market - have primarily North American and British passengers. So one would expect that the percentage of NLV outbreaks would be at least somewhat similar on both categories of ships.

 

But that is not the case at all.

 

Having worked on many of these ships - in both categories - I have been unable to see much difference. Certainly nothing that would feasibly cause such radically different results.

 

So the question that I am often asked, the question I often ask myself, and the question that I cannot answer is: "Why is the frequency of NLV outbreaks on these 2 different categories of ships so drastically different?"

[sail7seas]

So my musings were not off the mark of what you wished to discuss in this thread.

We're really not talking about one class vs. another but we are speaking about one (two) nationalities vs. others? Yes?

 

[Philip217]

sail7seas,

 

I don't have any questions or issues with nationalities.

 

The blend of nationalities on mass market cruises is pretty much the same as the blend of nationalities on luxury cruises.

 

My only questions are "Why do the people on the mass market cruises have so many more NLV outbreaks than the people on the luxury cruises?" "Other than the price they paid and the size of the ships, what makes them - or the situations they are in - so different?"

 

The CDC tells us that the annual flu season starts in China every year. They have determined that the flu virus thrives, mutates, and develops in the digestive tracts of many birds - primarily ducks and chickens. Which country has more ducks and chickens than any other? China, or course.

 

In Asia, more poor people contract Avian Flu (than their wealthier countrymen) because they have much more contact with live birds that carry the disease. That's hardly a surprise.

 

In South Asia and Africa, many people contract Malaria because they live in areas where the malaria-carrying mosquitos breed, and many do not have access to anti-malarial medicines. No surprises or mysteries there.

 

So what is the factor(s) that separates luxury cruise passengers from mass market passengers? They all come from the same places. One group gets sick frequently; the other group does not.

 

Why is that?

What can we hope to learn from this?

[gelo7]

sail7seas,

 

You can google Norwalk Virus and find some very interesting numbers on breakdown by nationality.

 

We already know that Norwalk Virus is more prevalent in North America and the UK than it is in many other parts of the world. Just as we know that Avian Flu is more prevalent in Asia, Malaria is more common in Southeast Asia, and HIV is more prevalent in Africa.

Who knows why, but that's what the numbers tell us.

 

Knowing that the overwhelming majority of cruisers comes from North America and the UK, it is hardly surprising that NLV is so common on cruise ships. The fact that more NLV outbreaks are seen on all ships sailing from North America, than on all ships sailing from most other continents is also not surprising.

 

The fact that cruise ships carrying primarily Germans, Italians, Chinese, Russians, or Japanese almost never have NLV outbreaks is also not a surprise. NLV is very rare in those countries, and so is rarely brought aboard by embarking passengers.

 

But what is perplexing is the fact that most cruise ships - luxury and mass market - have primarily North American and British passengers. So one would expect that the percentage of NLV outbreaks would be at least somewhat similar on both categories of ships.

 

But that is not the case at all.

 

Having worked on many of these ships - in both categories - I have been unable to see much difference. Certainly nothing that would feasibly cause such radically different results.

 

So the question that I am often asked, the question I often ask myself, and the question that I cannot answer is: "Why is the frequency of NLV outbreaks on these 2 different categories of ships so drastically different?"

 

Interesting....

[steamboats]

The fact that cruise ships carrying primarily Germans, Italians, Chinese, Russians, or Japanese almost never have NLV outbreaks is also not a surprise. NLV is very rare in those countries, and so is rarely brought aboard by embarking passengers.

 

Sorry, I think it was Churchill who said don´t believe statistics you didn´t fake by yourself. It´s totally nonsense that Germans do have less Norwalk cases than Americans. Last year we had a pretty worse Norwalk season here in Germany. But you won´t find any statistics on that. Two river cruise ships had been quarantined last season. Here in Munich several schools, kindergartens and daycare had to close down to be cleaned upside down. I never heard of anything like that before. And BTW it wasn´t called Norwalk before, it was simply a stomach flu.

 

As for this year newspapers already put out warnings. Last week another river cruise ship on the Rhine river had been quarantined by the local health authorities. O.k., I have to admit it was a Dutch ship with Brit passengers. But it happened on the German part of the Rhine river. The source of infection has not been located (and I doubt it ever will).

 

The fact that less German cruise ships are listed in the statics may have several reasons. First of all CDC is an US authority. Therefore they can only list Norwalk cases on cruise ships which are hitting an US port. And actually there´s only one real German cruise ship operating under German flag, the MS Deutschland.

 

As in the US there are no published statistics on Norwalk cases in any kind of land based facilities here in Germany like hospitals, nursing homes, schools, kindergartens or day care. Nor do we have any kind of statistics about Norwalk cases on any kind of vessels hitting a German port (neither river nor ocean). Norwalk has to be reported to the federal authority called Robert-Koch-Institut but resposible for any kind of action are the local health authorities.

 

BTW, DH suffered from Norwalk on Christmas two years ago. Maybe that´s why we are heading for a cruise this year (hey with a "US" cruise line, a mass cruise line, with US passengers and with our DD - sounds like this is gonna be a very risky vacation!!:D The good thing is: This is going to be a Med cruise - no CDC recordings for that one!).

 

steamboats

[sail7seas]

SoWhat can we hope to learn from this?

 

 

That people learn to wash their hands, wash their hands, wash their hands........

[kitty9]

We do know that far fewer children and older/infirm passengers travel on luxury ships.

I'm not an authority on either of these two groups.

 

 

As far as older passengers on luxury lines is concerned, your comment totally incorrect. In fact, the luxury lines such as Seabourn, Silversea and Crystal have a much higher average age than any of the mass market lines. On any given cruise, the average age on these lines can go well above 65. I've cruised on all three of those lines and I was one of the youngest passengers on board in my early 50's.

 

The reasons the small ships don't encounter those problems can be attributed to the following: Less children, fewer passengers, better crew to passenger ratio, smaller ships mean less square footage to keep clean, fewer public rooms, longer itineraries mean less passenger turnover and less a chance of passengers coming on board already sick.

[Philip217]

steamboats,

 

Actually if you use Google, you can discover how many cases of norwalk were reported last year in Germany or just about any other country. Nearly every country in the world has reported some cases of NLV, but not nearly as many as in North America. If you dig deeper, you can even find out how many ships under any number of national flags had illness outbreaks - not just Norwalk illness, but many others as well. And with today's news reporting, any location on earth that has any significant illness problem is on CNN and BBC within the hour. When 1 baby in rural China was ill from Melamine contamination, the entire world heard about it the same day. Do you think that any cruise ship could have several hundred passengers sick with NLV - anywhere in the world - and keep it a secret?

 

But at the end of the day, I really don't care how many Germans -or any other nationality - had NLV last year.

I am only trying to discover why the luxury lines have so very few NLV outbreaks, when the mass market ships have so many.

 

kitty9,

You bring up an interesting point. Although the luxury lines do generally carry an older average demogropahic, they do not generally carry so many older/infirm pax as the mass market lines. By that I mean those who may be physically unable to keep themselves as clean as the rest of the population - and those whose immune systems may not be as strong as others. A large mass market ship typically carries between 40 and 200 passengers in wheelchairs, another 50 with oxygen masks, and an additional 100 with walkers/scooters, etc. Luxury ships rarely see anything like that. They don't have the handicapped accessibility that large ships offer. Are all these people able to easily shower once or twice every day, and make a quick trip to the washroom every few minutes to wash their hands? Could this be a factor? I don't know - but wish I did.

 

One of the questions that often comes up relates to the higher than average number of outbreaks on the ships of Holland America Line. HAL ships nearly every year have the highest - or one of the highest - number of NLV outbreaks. There is a bit of a myth about HAL pax being older than most. Actually it is true - to a small extent - on their older ships. But it is not true on their larger ships. The HAL Vista ships carry an average age of 46. But nearly all of the HAL ships (large and small) have had quite a few outbreaks - except the Prinsendam, which has had very few. What is the difference? The Prinsendam does carry an older demographic, on longer, pricier, cruises - more like the luxury lines.

 

While true that smaller ships have less square footage to keep clean, they also have far fewer cleaners to keep it clean. In that regard, the big ships have the advantage. I have far more cleaners per passenger on my large ship than Seabourn ever could hope to have. I carry giant NLV fogging machines that can completely sanitize an 1100 seat theatre in just a few minutes. Seabourn doesn't even have space to store something like that. Nor do they have the staff required to operate those machines.

 

You make a good point about longer itineraries, with fewer infected passengers boarding. But one of the problems with that is, once the "bug" gets a foothold on a ship, the best way to get rid of it is to get all the passengers off as quickly as possible. On longer itineraries, the infected passengers keep passing it to the crew and each other. There is a theory that one of HAL's problems with so many outbreaks is their generally longer itineraries. Carnival, on the other hand, has the world's shortest average itineraries - and the most embarkations of new (possibly infected passengers) and has the lowest outbreak record in the mass market side of the cruise industry.

 

Do you think that the lower number of children on luxury lines means lower outbreaks?

I thought the same.

But Carnival has one of the highest average child counts on their ships - and has the lowest outbreak numbers of any mass market line. Nobody else is even close - except the luxury lines.

 

Back to the original questions:

Why and how is it that the luxury lines are able to have so incredibly few NLV outbreaks, while the mass market lines have so many - and how can we learn from this to keep ourselves well on a mass market cruise?

 

By the way, I have worked on ships for decades. I have been through dozens of outbreaks, sometimes with many hundreds of passengers and crew very ill. I have shaken hands with literally thousands of infected passengers (usually without knowing they were infected). I have visited sick pax in their cabins, cleaned up vomit and diarhhea from infected pax, packed their infected belongings for them, pushed them in wheelchairs to the ship's hospital and off the ship to get them home. Most of these people were suffering from one of the thousands of mutations of the Calici Virus - better known as Norwalk Virus. Not once have I ever suffered from the Virus. All the experts tell me that there is no immunity from Norwalk - except possibly for a very few days after you have just recovered from it. I am as puzzled about not catching it as I am about the paradox of luxury lines seeing it so rarely.

 

I wish somebody could come up with a definitive answer.