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Food Safety News

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Real People, Real Consequences Behind Statistics

A few weeks ago I was looking at the 2009 FoodNet data and started thinking about the upcoming release of new numbers on the burden of foodborne illness in the United States.

As you might recall in 1999 Mead and colleagues published estimates of the annual burden of foodborne illness in the U.S. These estimates – 76 million ill, 325,000 hospitalizations, and 5,000 deaths – have been cited by government, academics, citizen groups, and even industry as a call for action to improve food safety nationally and internationally.

Ten years ago, who anticipated the deluge of “Monday night quarterbacks” today eager to criticize a sincere attempt to characterize a serious public health and individualal health problem in our country? Yes, it is time for revised estimates and I, along with others, eagerly anticipate release of the new estimates rumored to occur sometime this next week.

Undoubtedly, the revised estimates will more accurately reflect truer incidence of foodborne illness. Credit must be given to public health that has strengthened detection, surveillance, and investigation of illnesses and outbreaks at the local, state and federal level. I can only imagine the obstacles that were overcome for implementation of electronic laboratory reporting or establishing NORS, the national outbreak reporting system. Data from both are likely to be used to calculate the forthcoming estimates.

Mead et al. were clear as to the limitations of the data sources used in their seminal 1999 article. The authors described several assumptions that were made such as uncertainty in the degree of under-reporting and the frequency of acute gastroenteritis in the general population.

For example, in 1999 few public health laboratories could test for norovirus in food or stool. Mead et al. attributed 30 percent (23 million) of the estimated 76 million illnesses to norovirus. Thanks to better laboratory detection and understanding of how norovirus spreads, the percentage of norovirus illnesses attributable to food in is likely to drop considerably in the new estimates.

A better norovirus estimate 10 years after 1999 does not imply that Mead et al. were careless in their methods. Rather, it highlights advancements in basic sciences and public health.

Recently, there has been no shortage of critics willing to dispute the 5,000 deaths Mead et al. attributed to foodborne illness. In June 2010 the Foodborne Disease Active Surveillance Network (FoodNet) published preliminary surveillance data for 2009 showing 74 deaths caused by the 10 foodborne pathogen it tracks. FoodNet sites represent about 15 percent of the U.S. population, which extrapolates to about 500 U.S. deaths caused by foodborne pathogens in 2009, considerably lower than the 5,000 deaths estimated in the Mead article.

However, the 500 estimated deaths would not include patients who died from a foodborne illness but who were not laboratory confirmed with a pathogen. Furthermore, I know from personal experience that patients die from injuries caused by foodborne illness after public health involvement has ceased. These patients are not counted as food related deaths.

Using death certificate data to identify foodborne illness related deaths is problematic. For example, the certificate might list renal failure as the cause of death with no mention of the shigatoxin E. coli infection the decedent had two months prior. This patient also would not be counted in food death data.

The effort to estimate the “true” number of illnesses, hospitalizations, and death associated with foodborne illness requires use of many data sources and statistical adjustments to account for under-reporting and other unknown elements.  We need the best data we can get to use to make decisions on how and where to fight foodborne illnesses. 

The new estimates will certainly be scrutinized and used to promote different agendas. Remember, the data is only as good as the surveillance.  We need to continue to support local, state and federal public health.  They need the resources to keep us all healthier.

I also encourage everyone to pause and remember that the estimates represent a compilation of individuals – hundreds and thousands of people I have met personally–my clients. Thankfully, most individuals will experience mild symptoms and think of their illness as a minor inconvenience. For an unfortunate few, foodborne illness will mean physical and mental anguish, financial expenditures, long-term consequences, or death.

Real people, real consequences….

© Food Safety News
  • Bill,
    You state, “Mead et al. attributed 30% (23 million) of the estimated 76 million illnesses to norovirus.” (Note for anyone reading the Mead study. It uses the earlier term “Norwalk-like virus” rather than “norovirus.”) Table 3 “Estimated illnesses, hospitalizations, and deaths caused by known foodborne pathogens, United States” estimates the number of foodborne illnesses caused to norovirus as 9,200,000. That is 66.6% of the illnesses due to known pathogens but only 12.1% of the 76,000,000 total estimate.
    Are there different numbers somewhere else in Mead?
    I’m particularly interested because the CDC’s “Norovirus: Technical Fact Sheet (http://www.cdc.gov/ncidod/dvrd/revb/gastro/norovirus-factsheet.htm and last updated 2-23-10) states, “In the United States, CDC estimates that more than 21 million cases of acute gastroenteritis each year are due to norovirus infection, and more than 50% of all foodborne disease outbreaks can be attributed to noroviruses.
    “Among the 232 outbreaks of norovirus illness reported to CDC from July 1997 to June 2000, 57% were foodborne, 16% were due to person-to-person spread, and 3% were waterborne; in 23% of outbreaks, the cause of transmission was not determined. Among these outbreaks, common settings included restaurants and catered meals (36%), nursing homes (23%), schools (13%), and vacation settings or cruise ships (10%).”
    Unfortunately, the website page does not provide a source for those numbers.
    Thus, Bill, it appears the CDC is one of those “Monday night quarterbacks” you mentioned. That would put them in good company.
    In his 11-22-10 Food (Safety) Fight blog, “76 million food borne illnesses last year. Really?” (http://www.meatingplace.com/MembersOnly/blog/BlogDetail.aspx?blogID=10), former Under Secretary for Food Safety at USDA, Richard Raymond, MD, wrote, “I have blogged on this before, but those politicians pushing for a change in food safety keep stating that , ‘Last year, 76 million Americans were sickened by a food borne illness and 5,000 died’ and that ‘our food safety system is a threat to the public’s health’.
    “They seem to be following the premise that to create change, first you must create a sense of urgency, as explained in John Kotter’s book, ‘Leading Change’”.
    “As long as they keep trying to create that sense of urgency with shaky numbers, I will keep blogging away…”
    Later in his replies to comments, Dr. Raymond pointed out, “The [Mead study] added [norovirus/Norwalk-like virus] as a foodborne illness for the first time in calculating annual illnesses.” Hmm. That surely helped get the numbers up.
    Bill, “the deluge of ‘Monday night quarterbacks’ today eager to criticize a sincere attempt to characterize a serious public health and individual health problem in our country” is the way that science works. The “sincerity” of the attempt is irrelevant to scientific progress. What matters is accuracy.
    As was pointed out on March 8, 2010 in Food Safety News by your associate, Alex Ferguson, the editors of the CDC’s Emerging Infectious Disease (the same magazine that published Mead) believed its key methodology was questionable enough to publish “Deaths due to Unknown Foodborne Agents” by Paul D. Frenzen (http://www.cdc.gov/ncidod/EID/vol10no9/03-0403.htm) in September 2004. Though Frenzen’s article only questioned Mead’s estimate of deaths, his arguments apply equally well to Mead’s estimates of illnesses and hospitalizations.
    Why does that matter? Because all 3 of Mead’s widely quoted total estimates (76,000,000 illnesses, 325,000 hospitalizations and 5000 deaths) are based upon the acute gastroenteritis methodology that Frenzen refuted not upon the foodborne illness data in FoodNet.
    Considering the huge improvements and expansion of the FoodNet system and Frenzen’s gently written but withering critique, of Mead; the CDC is 5 years late in publishing a new study.
    Also, had anyone (particularly the peer reviewers) stepped back from the Mead estimate of foodborne illness and asked a few questions, s/he would have quickly realized how inflated Mead estimates were. A survey of a few hundred people, asking if they had experienced any illness, however mild, that they attributed to being foodborne in the last year would have provided a good check on Mead’s totally theoretical estimate. There is no evidence that Mead, et al, the peer reviewers or the editors of EID took that common sense action.
    However, in October 2009, the Pew Charitable Trust did exactly that during its survey about how “the majority of voters in NV, OH, NC, NH and WY support new government oversight of food.” The Pew just failed to mention the results of those 2 questions while trumpeting the results of the rest of the survey. Of the 2415 people polled only 9.2% believed that “in the past year [s/he] had a bout of food poisoning or gotten sick from eating what [s/he] believed to be contaminated food.” Only 11.1% believed a member of his/her immediate family had. Combined the incidence rate would be below 9% with a very high reliability.
    In 1999, the Census Bureau estimated the total population was 273,000,000 on 7-1-10. So if no got sick more than once, Mead’s estimate of 76,000,000 would have meant 27.8% of the population would have had a foodborne illness that year. That’s a long way from the under 9% of the Pew Trust’s survey…but maybe things have improved that much.
    Finally, as Caroline Smith DeWaal told me that the new CDC study was “in peer review” on 4-20-10; I will be astonished it the new estimates are released before the final vote on the FDA Food Safety Modernization Act is taken. As Dr. Raymond wrote in one of his replies to his blog cited above, “You lose your funding if everything is getting better.”
    Could the CDC be playing politics?
    As always, I will happily defend all that I have written. Or for more info on why the Mead study’s famous estimates should have been suspect from the day they were published, please write me at healthyfoodcoalition@gmail.com.

  • Doc Raymond

    As one of those Monday Night Quarterbacks, I would like to point out that it is not the accuracy of the report that I am so critical of, but more the often stated “last year 76 million Americans were sickened by a food borne illness, and 5,200 died from the same” and follow that with “our food safety system is a threat to the public’s health”. All meant to push for the Food Safety Bill and/or a single food safety agency. The report, written in 1999, has nothing to do with “last year”, and anyone making that statement should acknowledge that fact, and the fact that food borne illnesses from the most common bacterial pathogens are down 40% from the time that report was written. Yes, I am also critical of the multipliers used to estimate unreported illnesses, the use of the very high Noroviral infections they attribute to being food borne, and the use of GI illnesses of less than 24 hour duration in the total number. I, too, look forward to a much more accurate estimate of the impact, and I, too, will continue to push for a safer food supply, as we all know that can be done. But it can only be accomplished with a high level of discussion, using science based facts and numbers. Too often the discussion is just finger pointing and/or denial.

  • Jim Schmidt

    Mr. Hamill unfortunately you and the politicians that think like you are part of the problem. When public health is doing good instead of saying excellent let’s keep the funding at this level or improve what we have and increase spending and improve our outcomes you and politicians look to cut spending. Of course then you get some bad outcome and put all the blame on the organization you just raped of money and/or people.
    The only comments I have seen from you are negatives. I have never seen you come out and make any suggests on how to improve public health, I have very little respect for this type of behavior.
    Claiming a study should have been suspect since 1999 does not do us any good now it just seems like you want to say “neaner, neaner, neaner!” Childish.
    Finally Mr. Hamill, have you ever personally spoken with someone that does inspections of retail food establishments? How about someone that does foodborne illness investigations? Sure doesn’t seem like it to me. It does seem like you have a single track mind for the FDA and the FDA is only one aspect of the public health system in the USA.

  • dangermaus

    I’m not qualified to debate the numbers here, St. M, but I do want to point out that you’re falling back on the trick of emotional bullying. In your encouragement to “pause and remember…[your] clients”, I think you’re implying that people that oppose more government regulation in this area only do so because they don’t care about victims of food-borne illness. I would say that supports of more regulation in this area should “pause and remember” their liberty and freedom of choice that is lost when laws like this get passed.
    And… as if there would be no food-borne illnesses if the FDA was given more authority… That’d simply be impossible. I’ve never even seen any sort of estimate about how many food-borne illnesses we’d have after FSMA was implemented. Not to mention the argument (whatever on thinks of its merits) that FSMA would drive small producers out of business, leading to people eating even more highly-processed foods, contributing to more to our obesity and diabetes epidemics.

  • Bill,
    You state, “Mead et al. attributed 30% (23 million) of the estimated 76 million illnesses to norovirus.” (Note for anyone reading the Mead study. It uses the earlier term “Norwalk-like virus” rather than “norovirus.”) Table 3 “Estimated illnesses, hospitalizations, and deaths caused by known foodborne pathogens, United States” estimates the number of foodborne illnesses caused to norovirus as 9,200,000. That is 66.6% of the illnesses due to known pathogens but only 12.1% of the 76,000,000 total estimate.
    Are there different numbers somewhere else in Mead?
    I’m particularly interested because the CDC’s “Norovirus: Technical Fact Sheet (http://www.cdc.gov/ncidod/dvrd/revb/gastro/norovirus-factsheet.htm and last updated 2-23-10) states, “In the United States, CDC estimates that more than 21 million cases of acute gastroenteritis each year are due to norovirus infection, and more than 50% of all foodborne disease outbreaks can be attributed to noroviruses.
    “Among the 232 outbreaks of norovirus illness reported to CDC from July 1997 to June 2000, 57% were foodborne, 16% were due to person-to-person spread, and 3% were waterborne; in 23% of outbreaks, the cause of transmission was not determined. Among these outbreaks, common settings included restaurants and catered meals (36%), nursing homes (23%), schools (13%), and vacation settings or cruise ships (10%).”
    Unfortunately, the website page does not provide a source for those numbers.
    Thus, Bill, it appears the CDC is one of those “Monday night quarterbacks” you mentioned. That would put them in good company.
    In his 11-22-10 Food (Safety) Fight blog, “76 million food borne illnesses last year. Really?” (http://www.meatingplace.com/MembersOnly/blog/BlogDetail.aspx?blogID=10), former Under Secretary for Food Safety at USDA, Richard Raymond, MD, wrote, “I have blogged on this before, but those politicians pushing for a change in food safety keep stating that , ‘Last year, 76 million Americans were sickened by a food borne illness and 5,000 died’ and that ‘our food safety system is a threat to the public’s health’.
    “They seem to be following the premise that to create change, first you must create a sense of urgency, as explained in John Kotter’s book, ‘Leading Change’”.
    “As long as they keep trying to create that sense of urgency with shaky numbers, I will keep blogging away…”
    Later in his replies to comments, Dr. Raymond pointed out, “The [Mead study] added [norovirus/Norwalk-like virus] as a foodborne illness for the first time in calculating annual illnesses.” Hmm. That surely helped get the numbers up.
    Bill, “the deluge of ‘Monday night quarterbacks’ today eager to criticize a sincere attempt to characterize a serious public health and individual health problem in our country” is the way that science works. The “sincerity” of the attempt is irrelevant to scientific progress. What matters is accuracy.
    As was pointed out on March 8, 2010 in Food Safety News by your associate, Alex Ferguson, the editors of the CDC’s Emerging Infectious Disease (the same magazine that published Mead) believed its key methodology was questionable enough to publish “Deaths due to Unknown Foodborne Agents” by Paul D. Frenzen (http://www.cdc.gov/ncidod/EID/vol10no9/03-0403.htm) in September 2004. Though Frenzen’s article only questioned Mead’s estimate of deaths, his arguments apply equally well to Mead’s estimates of illnesses and hospitalizations.
    Why does that matter? Because all 3 of Mead’s widely quoted total estimates (76,000,000 illnesses, 325,000 hospitalizations and 5000 deaths) are based upon the acute gastroenteritis methodology that Frenzen refuted not upon the foodborne illness data in FoodNet.
    Considering the huge improvements and expansion of the FoodNet system and Frenzen’s gently written but withering critique, of Mead; the CDC is 5 years late in publishing a new study.
    Also, had anyone (particularly the peer reviewers) stepped back from the Mead estimate of foodborne illness and asked a few questions, s/he would have quickly realized how inflated Mead estimates were. A survey of a few hundred people, asking if they had experienced any illness, however mild, that they attributed to being foodborne in the last year would have provided a good check on Mead’s totally theoretical estimate. There is no evidence that Mead, et al, the peer reviewers or the editors of EID took that common sense action.
    However, in October 2009, the Pew Charitable Trust did exactly that during its survey about how “the majority of voters in NV, OH, NC, NH and WY support new government oversight of food.” The Pew just failed to mention the results of those 2 questions while trumpeting the results of the rest of the survey. Of the 2415 people polled only 9.2% believed that “in the past year [s/he] had a bout of food poisoning or gotten sick from eating what [s/he] believed to be contaminated food.” Only 11.1% believed a member of his/her immediate family had. Combined the incidence rate would be below 9% with a very high reliability.
    In 1999, the Census Bureau estimated the total population was 273,000,000 on 7-1-10. So if no got sick more than once, Mead’s estimate of 76,000,000 would have meant 27.8% of the population would have had a foodborne illness that year. That’s a long way from the under 9% of the Pew Trust’s survey…but maybe things have improved that much.
    Finally, as Caroline Smith DeWaal told me that the new CDC study was “in peer review” on 4-20-10; I will be astonished it the new estimates are released before the final vote on the FDA Food Safety Modernization Act is taken. As Dr. Raymond wrote in one of his replies to his blog cited above, “You lose your funding if everything is getting better.”
    Could the CDC be playing politics?
    As always, I will happily defend all that I have written. Or for more info on why the Mead study’s famous estimates should have been suspect from the day they were published, please write me at healthyfoodcoalition@gmail.com.

  • Mr. Schmidt,
    As I have a very uncommon name, I suggest you do a web search with the correct spelling,” Harry Hamil.” You won’t find any instance of my having recommended that we cut spending on food safety regulation. And if you review all the comments, I believe you’ll find most are directed at correcting inaccurate or misleading statements from proponents or journalist doing press release journalism; thus, they generally must be fairly negative.
    I was one of the founders of Hospice Atlanta, the National Hospice Association, the Healthy Food Coalition, the Black Mountain Tailgate Market and the Mountain Tailgate Market Association and married to a medical student, resident and practicing family physician for 10 years. Is that enough in public health arena for you?
    As we have a certified home kitchen and a year-round store for local, healthy food, yes, I’ve talked with inspectors of retail food establishments. In addition, I have talked for hours with the epidemiologist who testified to the Senate HELP Committee on 10-22-09 and with an epidemiologist at the CDC trying to understand one group of outbreaks this year.
    As for my comments on the 1999 Mead study, I suggest you question my critique and not my character. I majored in math and spent 35 years in my first career teasing meaning from statistics; so I have a problem when people try to tell that a group of numbers means one thing when I can hear those numbers telling a different story.
    Have I answered your questions? If not, please write me at healthyfoodcoalition@gmail.com and we can set up a time to talk by phone so you’ll have an opportunity to ask any other related question or just give me a piece of your mind.
    It is always great to have someone engage me of the issues I have raised. I hope you will e-mail me.

  • K Rivers

    I won’t pretend to know everything on this issue. I’m not a lawyer, a scientist or a politician. However, as a person who almost died 4 months ago and a mother who lost my newborn son from a foodborne illness, I could not care less about the political crap involved in this issue. Believe what you want to about how our government should be run, this is about the safety of the American public. It shouldn’t matter if the mortality rate is 28% or 9%. People are dying from eating food in one of the most advanced countries on Earth. And to be totally honest, I don’t care if small producers will be driven out of business because they can’t afford to adhere to the new regulations. The listeriosis I caught was from eating produce I got at a farmer’s market. Never in a million years did I think that would happen in the US. We have food regulations here! In the past 4 months, I have had plenty of time to research the issue, and frankly, it’s frightening. If you can’t make your food safe and adhere to safety guidelines , you should not be allowed to sell it, period. I know I am simplifying the issue, but it is simple: We shouldn’t have to worry about getting sick from the food we eat. So please, do “pause and remember” when you’re arguing about the expense and the supposed loss of freedoms. Remember the name Simon Rivers. He lived for 15 hours and died from septic listeria while I watched from a wheelchair, fighting the same infection. If these are the “freedoms” you’re talking about, you can have them. I’d rather have my son back.

  • Mr. Schmidt,
    As I have a very uncommon name, I suggest you do a web search with the correct spelling,” Harry Hamil.” You won’t find any instance of my having recommended that we cut spending on food safety regulation. And if you review all the comments, I believe you’ll find most are directed at correcting inaccurate or misleading statements from proponents or journalist doing press release journalism; thus, they generally must be fairly negative.
    I was one of the founders of Hospice Atlanta, the National Hospice Association, the Healthy Food Coalition, the Black Mountain Tailgate Market and the Mountain Tailgate Market Association and married to a medical student, resident and practicing family physician for 10 years. Is that enough in public health arena for you?
    As we have a certified home kitchen and a year-round store for local, healthy food, yes, I’ve talked with inspectors of retail food establishments. In addition, I have talked for hours with the epidemiologist who testified to the Senate HELP Committee on 10-22-09 and with an epidemiologist at the CDC trying to understand one group of outbreaks this year.
    As for my comments on the 1999 Mead study, I suggest you question my critique and not my character. I majored in math and spent 35 years in my first career teasing meaning from statistics; so I have a problem when people try to tell that a group of numbers means one thing when I can hear those numbers telling a different story.
    Have I answered your questions? If not, please write me at healthyfoodcoalition@gmail.com and we can set up a time to talk by phone so you’ll have an opportunity to ask any other related question or just give me a piece of your mind.
    It is always great to have someone engage me of the issues I have raised. I hope you will e-mail me.

  • dangermaus

    Do you think that your statement of “I could not care less about the political crap involved” (and others) indicates that you’re thinking rationally, or that you’re reacting to your personal pain? I’m sorry for your tragedy, and I’m sure I can’t imagine your loss. However, you’re saying that agencies of the government (one that is mistrusted by a lot of people) should be empowered to punish people for not following their rules. You’re also assuming that the results of the legislation will work out as initially intended (even though there are no stated targets for how much food-borne illness should be reduced). When is it ever the case that trying to do something so complex (as regulating food) works out neatly?
    I’m sure there are millions of Americans who think alcohol should be banned because of the thousands of deaths it contributes to annually. Should we ban cars because of the thousands of innocent passengers and pedestrians that die on the roads? Should we ban dachshunds because they’re more likely to bite humans than other breeds, and ban pit bulls because they are more likely to injure when they bite?