The outbreak is a series of similar events within a community or a particular region that is characterized by an illness the frequency of which exceeds the expectancy of a norm. The quantity of instances that show that the occurrence of an outbreak depends on the present agent of an infection, the size of the population that has been affected by the infection, previous instances of outbreaks, and lastly, the place and time when the outbreak occurred (Manitoba Health n.d., p. 1). In the majority of cases, an outbreak is related to an infectious disease, but an outbreak can also occur in a case of a non-infectious disease, for example, cancer or diabetes. However, the methods of investigation are similar for all types of outbreaks (Outbreaks investigations n.d., par. 1).
Why Investigate an Outbreak
The main reason for an outbreak investigation is the identification of its source, When the source of an outbreak is identified, then control is being established in order to prevent future instances of an outbreak. Furthermore, an outbreak investigation is often implemented to train new employees and learn about the past disease and the methods of its transmission within a population. The decision to conduct an outbreak investigation is directly linked to its severity, the possibility of further spreading, or the political reasons influenced by a particular degree of deep concern expressed by the population (Outbreaks investigations n.d., par. 8).
The outbreak that will be investigated in this paper is the outbreak of the foodborne diseases because of an array of reasons such disease still remain a health challenge worldwide. Some foodborne diseases are taken under control while others pose a new danger to the population. Particular sections of a population under question are more likely to be affected by a foodborne disease because of their age, immunity suppression, or other conditions that affect the susceptibility to the disease.
Furthermore, individuals that travel to new environments can often be exposed to unfamiliar foods that may negatively affect their health. In the majority of countries, foodborne diseases occur as a result of people consuming food that is being prepared outside the house, and that is being frequently exposed to poor hygiene. Such challenges require continuous adaptations to the ever-changing environment that affect the spreading of the foodborne diseases as well as the development of innovative methods of dealing with the mentioned challenges (World Health Organization 2008, p. 5).
Public concern is one of the main features of an outbreak investigation. In investigating an outbreak, health authorities should find a perfect balance between the scientific aspect of an investigation and the ability to respond to public concern. Therefore, an outbreak investigation should complete a plan that outlines the ways in which relevant information is being presented to the concerned public. Furthermore, in some cases of an outbreak, close communication with the public will be instrumental in finding out about new instances of the disease under investigation.
Another important participant in the outbreak investigation is the media. It is an interface of the communication between the health organization and the public. By establishing a close connection with the media, a health organization that conducts the investigation will have an option to facilitate the reporting about the disease cases, give the public information about the ways the disease can be avoided, and maintain the support from the public (World Health Organization 2008, p. 7).
The relationship between a further investigation of the occurred outbreak and the measures of control relates to the amount of information about the known sources of an outbreak as well as they way these sources was transmitted (Investigating an outbreak n.d., p. 6).
Investigation Proper
Detection
A foodborne disease outbreak is an occurrence that is characterized by two or more individuals experience similar symptoms after being exposed to the same source of food, or there is otherwise evidence that particular food was a cause of the outbreak.
On the early morning of April 18th, the Department of Health in London received a concerned call from a mother whose son and daughter were suffering from a severe case of vomiting and nausea. They both got sick during the previous day and consumed some over-the-counter medication that gave no results. The children visited a Birthday party where they consumed some burgers and fries along with other children. The mother had also contacted other parents to ask whether their kids were okay. It had appeared that those children were having the same symptoms of nausea and vomiting. Furthermore, the Department of Health received similar calls in the course of the two following days. This was an obvious case of a foodborne disease outbreak.
The etiologic agents of the foodborne disease outbreak include bacterial toxins, bacterial infections, viruses, parasites, and noninfectious agents. A foodborne disease is usually accompanied by vomiting, diarrhea, nausea, and cramps in the abdominal area. By its own definition, foodborne diseases are being transmitted through the consumption of food; however, some of the bacteria agents can be transmitted through water, contact with animals as well as direct contact of person to person (Washington State Department of Health 2013, p. 3).
The contaminated food that may have been consumed by an individual may be contaminated from nature. They become acceptable for consuming after cooking. The examples of such foods are pork that can be affected by Yersinia enterocolitica, seafood affected by Vibrio parahaemolyticus, milk products affected by Salmonella or Cryptosporidium parvum and others. The second group of bacteria-contaminated food is the food that has been contaminated by poor handling. Poor handling includes contamination through dirt, unwashed hands, and infected lesions.
The virus of Staphylococcus aureus can easily contaminate food from the handler’s skin and quickly grow at room temperature thus producing a dangerous toxin that is stable to heat and cannot be eliminated by the process of cooking. The third way in which food products can be contaminated is the way of cross-contamination through other foods or the surrounding environment. The most common way is the cross-contamination of bacteria that come from raw meat and eggs on raw foods by the means of kitchen utensils and unwashed surfaces. The last and the least common way of food contamination is contamination by the means of intentional acts.
Microbiologic Investigation
On April 20th, the Department of Health made a visit to the emergency room at the local hospital to look at the records of thirty-five patients who all came in with the same problem of vomiting, nausea, and abdominal pains. The most prevalent symptom was vomiting that was detected in ninety-one percent of the affected individuals, then went diarrhea with eighty-five percent and abdominal pains with sixty-eight percent.
The average body temperature of the patients was 37.8C. All of the performed blood tests taken from fifteen patients showed a significant increase in white blood cells. By April 21st, there have been eighty-five instances of reported instances of a foodborne disease. All patients were recent visitors to their local fast food restaurant. The dates of the reported cases of illness were from April 18th to April 21st. The average age of affected patients was 15 years, ranging from seven to twenty-two years old.
Source: The common food item identified through the means of interviewing was a beef burger. When the food had been taken for analysis, there had been no evidence of a harmful bacteria. Thus, the food was probably contaminated by the means of cross-contamination from other products like salads, eggs, or badly prepared shellfish.
Incubation period: The period of incubation for a foodborne illness ranges from one day to one week. The most of the reported instances of illness were on April 18th-20th.
Leading Hypothesis: an infection that was spread through food or a drink served at the fast food restaurant.
Environmental Investigation
On the basis of the clinical findings and the results of the interviews outlined above, the health investigators concluded that an outbreak was caused by a viral pathogen that most likely appeared in the food due to the process of cross-contamination in a fast-food restaurant between April 18th and April 21st. Thus, the environmental investigation consisted of interviewing restaurant staff on the types of products they handled, the meals served to customers as well as the places each employee worked in the restaurant.
Furthermore, restaurant employees had been questioned about whether they wore gloves as well as the hand washing policy in the kitchen, and whether anyone from the staff had been ill between April 18th and the 21st. In the restaurant, the burger preparing area had its own refrigerator. When order had been placed by the customer, burgers were made separately by an employee responsible for burgers. Each day new supplies of meat, lettuce, cheese, and vegetables were added to the refrigerator along with the products left from the previous day. However, when the restaurant had been open and orders had been coming in, there was no time for keeping all required products for a burger in a refrigerator. Furthermore, the containers for products were not cleaned on a regular basis.
Thus, the Health Department closed the restaurant on April 22nd. There was distinct evidence that the restaurant’s food had been the primary reason for the outbreak. The action of closing the restaurant was solely based on the circumstantial evidence (the restaurant had some issues with improper food handling). Because there was a number of unsanitary actions, closing a restaurant for a short period of time had been the smartest solution until the problems were resolved. Despite the fact that the most likely reason for the foodborne disease outbreak had been identified, it is crucial to conduct a further investigation because:
- the actual reason may not be the restaurant; however, it is most likely;
- more detailed information is required on the outbreak to find out whether the restaurant is safe to open again;
- more detailed information is required to prevent the outbreak from happening again (Gastroenteritis at a university in Texas n.d., p. 16).
Dose Response
The dose response is available in a case when the possibility of a foodborne illness is directly linked to the time of the exposure to the harmful ingredient. For instance, if an individual ate two burgers was more likely to become ill than a person that ate one burger, the dose response takes place. Thus, in order to support the hypothesis of a harmful exposure, the dose response must be supported. Evaluating a dose response is important in an outbreak when a population had been exposed to the same harmful agent, as the case with the fast food restaurant.
Paying attention to the design of the investigation is crucial in making sure that the dose response can be easily determined. The first step of the dose-response evaluation was asking questions about the levels of exposure to the harmful ingredient, for example, how many and how often the burgers were eaten. After evaluating the number and frequency of the eaten burgers in a fast food restaurant, then information on the relative risks, levels of exposure, and odds ratios is identified. Statistical significance of the dose-response metric can be calculated with the help of statistical test (World Health Organization 2008, p. 35).
Case-Control Study
In a circumstance like a case with the burgers, there is no clearly identified cohort of all individuals exposed to the illness because it was clear that not all cases were reported. Furthermore, not all non-exposed individuals can be asked questions about how they were feeling. In this case, when the most relevant information had been gathered. In this case-control study, the cases of ill individuals are compared to those of healthy (World Health Organization 2008, p. 30). The health institution used a questionnaire for getting information about the cases of an outbreak:
In this case-control study, 92% of the reported cases of illness had consumed the burger compared to 23% of the controls. Thus, the burger is suggested to be the primary reason for an outbreak. However, the relative risk cannot be identified with the use of the above table, because the quantity of all affected individuals is not known. Instead odd ratio is used and calculated as the cross-product:
Odds ratio= Ate the burger cases*Did not eat the burger controls/Ate the burger controls* Did not eat the burger cases
Odds ratio=35*50/15*3=38,8
The above-calculated odds ratio suggest a possible but not close relationship between the foodborne disease outbreak and the burger served at the fast-food restaurant as a primary source. Since the case-control study had been conducted two days after the last case of an outbreak, there was a possibility that the harmful bacteria was not present in the tested samples of the burger.
Discussion and Conclusion
Appearing cases of foodborne disease outbreak still continue to arise and disturb the health care system. Furthermore, because of a variety of harmful bacteria, it is hard to successfully detect and treat the outbreak (Stephen & Ostroff 2000, par. 1). The foodborne disease outbreak investigated in the paper was indeed an outbreak because it was ‘defined as two or more illnesses caused by the same bacteria that are linked to eating the same food’ (Virginia Department of Health 2015, par. 1). All of the acquired results were issued to the public and the media in order to ensure that the cases of illness would not repeat again.
The fast food restaurant had been re-opened by the Public Health England when all testing were made, and there were no signs of poor food handling left. Furthermore, the Department of Health had encouraged the public to evaluate the risks associated with a foodborne disease and to carefully choose the places where to eat, paying close attention to the way employees handle the products (Department of Health n.d., par. 7).
The department of health had interviewed the individuals affected by the illness and made sure that the symptoms were treated and eliminated as soon as possible. To prevent the illness cases from occurring in the future, additional evaluation of the restaurant conditions and food handling habits had been conducted. Despite the fact that there had been no distinct type of bacteria found during the testing, the most likely source of the illness was the burger ingredients cross-contaminated by means of poor food handling.
A foodborne disease outbreak is not the one to be ignored or disregarded, so the Department of Health did everything in its power to quickly resolve the issue and make sure that no serious consequences occurred in those individuals who had suffered from the foodborne disease outbreak. Lastly, it is important to note that the media did a great job in providing the public with all necessary information on the outbreak, the ways to report it in a case of an illness, as well as the methods of prevention.
Reference List
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Stephen, M & Ostroff, M 2000, Public health Systems and emerging infections: assessing the capabilities of the public and private sectors: workshop summary. Web.
Virginia Department of Health 2015, Foodborne disease outbreaks. Web.
Washington State Department of Health 2013, Foodborne disease outbreaks. Web.
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