Food Safety and Environmental Health Blog : Disease Prevention, Public Health, Sanitation Information & Analysis : Environ Health Associates

In years past the practice in the US was to require a health certificate to work in the food industry. While on the surface this sounds like something to consider, the use of medical evaluation of food workers was often done without specific tests, medical personnel relying on medical history and a physical exam. Without specific tests carriers of infection are difficult to detect, and such exams alone cannot predict future health status. In many parts of the world, this practice is still evoked while it  is no longer considered to be necessary in the US.

Since a medical screen is relied upon by some as a preventive measure, our scientific methods of developing food safety systems makes us have to evaluate the validity of this process. We must determine the reliability of results for preventing foodborne illness alone. In a food safety system, other communicable disease such as sexually transmitted disease, or strictly respiratory diseases like TB or influenza do not enter into the hazard analysis..

A medical screening process proven effective through a validated method would be in conformance with ISO22000:2005 or HACCP methods; requirements based on them would then be food safety preventive measures.

To be in conformance, tests must be specific for etiological agents of disease, be predictive of communicable disease status at time of employment and be relative to future health status. Reliable tests provide the validity for a medical exam at time of employment. Tests for Salmonella typhi, Giardia, other protozoan and higher parasites, skin and upper respiratory infections (staph and strep) and other chronic or semi chronic disease (hepatitis A-D, mononucleosis)  transmissible through food might be considered. In addition, triage of employees might be beneficial in a “hazard analysis” context as one might try to discriminate and sort between:

• 1) Those who are not infected and not likely to be infected in the future
• 2) Those who are likely to be infected in the future
• 3) Those who are likely to be infectious now
• 4) Those for whom immediate care might make a positive difference in outcome

The food safety and public health benefits of any medical-screening model needs to be tested before including it in a food safety management system.

In the past, the medical screening of food workers has proven not to be predictive of future infectious status and both the public health and medical communities question its value in public health protection.

While each country and region has its own relatively unique disease transmission issues, prevention of disease in the first place is always better than testing for it afterwards.

Public health policy and food protection are issues that we expect the new Obama administration to address eagerly. Financial problems, wars in Afghanistan and Iraq, and Home Land Security have shifted focus away from our core public health agenda, and now is the time to return our focus. Everyone agrees that public health programs have suffered in the last eight years. Keep in mind, however, that public health protection is possible in the US more so than in many places around the world. We have public health infrastructure, a little decrepit, but still there.

The new administration should take an accounting of what is on the ground now, what is working and what is not, and develop a comprehensive plan of action similar to the "President's Food Safety Initiative" of 1998.. Safety-net type programs that were instituted like PulseNet www.cdc.gov/pulsenet/ and FoodNet www.cdc.gov/FoodNet/  are now very valuable. If the new administration is wise, it will invest in these and other types of surveillance programs and set meaningful public health goals. Most importantly, the new administration must implement strategies to achieve its goals based on science and a risk assessment.

The Obama team should develop true partnerships where government and industry equally share the burdens of food protection. One possible way to do this is to strengthen the existing industry-driven, self-regulation model. The Obama administration can accomplish this through better federal agency oversight and verification of the entire food supply chain. Presently, there are major gaps in federal regulation of the US food supply that weaken industry efforts.  

Applying technology is a quick way to move forward rapidly. For example, the food industry is applying sophisticated food safety data capture devices in their food safety management systems. Programs are built into common platforms that run on the I Phone and PDA of a wide assortment. Data is also transmitted through the Internet to database management systems that track and analyze data-see http://www.scbs.net.au/index.htm. Tapping into the resources of industry food-safety professionals and the available technology can definitely strengthen public health protection.

“One big agency” to bring all regulation for the food supply under one umbrella is a compelling thought that the Obama team must evaluate. The new administration should consider first, however, how to enhance what is already functioning. There may be some advantages in combining some functions of the USDA Food Safety and Inspection Service-see www.fsis.usda.gov/and the FDA Center for Food Safety and Applied Nutrition-see www.foodsafety.gov/list.html.

Without question, the new administration should call for more coordination and better allocation of resources in both USDA and FDA, and then properly fund these agencies to meet the administration’s public health goals. The last administration failed to recognize that our agencies have been less than capable in managing the risks in the US food supply. This administration should first honestly evaluate the successes and failures of current public health policies as regards food safety and other pressing matters and then lead us forward.

We recommend that the administration seriously look at the Office of the Surgeon General- see www.surgeongeneral.gov and strengthen the role of the nation’s "Chief Health Officer". The Surgeon General has not voiced any support for food safety efforts since he last spoke out publically on the issue, back in 1999. This vastly underutilized post should come to the fore under President Obama. We should expect the Surgeon General's Office to take initiatives in the interest of public health to elicit more support and involvement in food safety from the medical and public health communities, and to speak to the American people about food protection.

Validation is a key part of the verification process. Verification in HACCP requires that we first determine if the process has effective controls and secondly that the controls are operating as required. Basically, what every HACCP Plan has required since the inception of HACCP is valid documentation. The concept of validity means much more however, and the world body known as the International Standards Organization in Geneva Switzerland has developed an ISO standard for managing HACCP that requires that the operator not only monitor the system and keep valid records, but that the systems for control have been validated. This means controls must meet a standard that provides assurance that when they are met, hazards are under control. Without such standards there can be no validity to measurements.

Validity means the degree to which an instrument, selection process, statistical technique, or test measures what it is supposed to measure. Without standards it is impossible to measure as there is nothing to compare the measurements to. ISO approaches these issues by providing the definitions below.

Notice the term evidence is used in the definition of validation. Without microbiological, chemical, physical and radiological tests results (evidence), hazards will go unrecognized. Without criteria for the tests they will not provide the evidence required by ISO to ensure safety. Notice also that end products can not be assumed safe simply by monitoring a critical limit like chlorine residual in a water system, verification of the process, validation of the critical limits, and documentation are also necessary.

Notice in verification that specified requirements must be provided.

An example of a problem when validation and verification is ignored might be a situation where a water quality management system has identified that a significant contamination problem exists and assumes that by chlorination the system will be capable of effective control of hazards, but does not validate that the controls are effective. The problem with this is that EPA for example requires not only that the system maintain an FAC between 0.2 ppm and 4.0 ppm but that the water is free (<10) of Legionella species as well as total coliform, and HPC ( below 500 ppm) . Verification of such a system is impossible without testing against these standards (criteria) and the hazards may be there in spite of a predefined upon critical limits, depending on a number of factors, most importantly, dead end loops, chlorine demand and monitoring methods.

Verification and validation are therefore both essential to water quality management systems and all HACCP systems. ISO provides in-depth and clear definitions for these terms below: ISO 22000:2005.

This outbreak is an example of scombroid poisoning. Scombroid enterotoxin is actually a heat stable bi-product of histamine, and results when dark-fleshed fish begin to decompose. Its one of the few illnesses through food that have a correlation directly to spoilage although there may be others (certain strains of C botulinum). Because the symptoms occur rapidly and are easily recognized by the victim as food related, few outbreaks go unreported and uninvestigated. This illness is an example of how reporting artifacts confound epidemiological statistics. A recent study by the Centers for Science in the Public Interest reported that fish and seafood are the vehicles most often identified in foodborne illness outbreaks. Failure to understand the effect of reporting bias in the data related to fish, makes that work and its conclusions flawed. In addition, that study also relied upon data on shellfish infections and intoxications, and ciguatera intoxication. These data also suffer from the same type of reporting bias issues.

However, tuna and other species of Scromboid fishes (jacks, mahi) have a very high risk of this hazard. Its occurrence is quite an important issue as HACCP has been in place in fisheries in the US for many years. Without rigorous supplier controls controlling risks all the way to harvesting, HACCP as an intervention in this illness is weak.

There is a corollary between Scomboid poisoning and other hazards such as those found in fresh produce, that lack a kill step.

UK: Tuna 'link' in sickness outbreak
05.dec.08
BBC News
http://news.bbc.co.uk/2/hi/uk_news/scotland/north_east/7767327.stm
A tuna meal may have been to blame for an illness outbreak at Aberdeen Exhibition and Conference Centre, NHS Grampian has said.
Twelve people needed hospital treatment after the emergency services were called out on Thursday afternoon.
The health board said the common link between the patients was a tuna dish for lunch. Samples are being tested.
One man who fell ill, who did not want to be named, said the symptoms were rashes, headaches and palpitations.

 

In a recent message to its members, Food and Water Watch says:

“Protecting Our Food: End Food Industry Self-Policing”. Consumers need strong standards and strong enforcement by government inspectors. The USDA must abandon attempts to let meat plants do their own inspections. The Food and Drug Administration needs new authority and resources to inspect food processing plants and should be reorganized so it can devote proper attention and inspection resources to imported foods.”

Food and Water Watch describes themselves as:

(Foodandwaterwatch.org is a nonprofit consumer organization that works to ensure clean water and safe food. We challenge the corporate control and abuse of our food and water resources by empowering people to take action and by transforming the public consciousness about what we eat and drink).

As practicing food safety experts, we have seen many improvements in food facility operations as a result of industry self-control procedures. However, a serious deficit exists when government fails to support voluntary, industry food-safety-systems with a public health goal in mind. To enhance industries efforts public health agencies should:

1.      Create mandatory baseline requirements for the entire food chain

2.      Effectively validate and verify industry efforts and coordinate them

3.      Ensure firms create food safety systems primarily to protect public health making this their primary goal

While meat, fish, poultry and juice have mandatory food safety systems, not all of the food supply is covered.

In the produce sector, we have only buyer driven pressure on producers throughout the supply chain to meet voluntary standards. Many retail firms such as Wal-Mart, Albertson's and Publix require their suppliers to maintain detailed food safety programs based on Hazard Analysis Critical Control Point. However in the absence of regulation (FDA may have primacy but does not exert its power until the fruit is processed), many non-compliant firms still sell to buyers in need of product.

There is no mandatory regulation and baseline of safety in the produce industry and many firms operate without a food safety system; while at the opposite extreme, we have exceptional firms with ISO based HACCP models controlling minute aspects of production from growing through distribution.

Industry self-policing is critically necessary in produce, however it is same in every food industry. This is the case because all day-to-day operation in any industry are in the hands of the firm. The challenge is for government to use its resources wisely and build upon industry efforts, while at the same time providing a strong safety net for the consumer.

Our response to Food and Water Watch and its members is:

1. Ending self-policing is not wise; we should strengthen self-policing.

2. Public health agencies should be more intelligent about the way they assure food safety for the American consumer and accept their responsibility for protecting the public health while delegating more of the monitoring the safety of the food safety system to industry.

3. Ending self-policing will not result in food protection, but just the opposite. Strengthening this model on the other hand holds a great deal of promise