Question

PLEASE wtite 2 pages for this assignment as much details & information.

This is the case it is a case control study because the disease has already appeared in subjects and it is known who is ill and who is not. The unknown in this situation is the exposure, and which specific exposure caused the disease. Case control studies are typically used for outbreaks such as this.

CASE & questions below. please help

This is what is known about the outbreak of disease: In your town, you are told that many people were taken ill with diarrhea after attending a wedding last week. In fact, of the 1000 people who attended the wedding, 150 were taken ill with diarrhea and this illness seems to be isolated to the wedding as other community members, who did not attend the wedding, have not been reporting any intestinal illnesses. Having established there appears to be an outbreak of food-borne illness, you are asked to conduct an investigation to identify which food item may have caused this illness. At the wedding, the guests chose from 15 different food items.

The two questions to be answered::

Now imagine that you have collected the data for this outbreak. What approach would you use to identify the food item most likely to have caused this illness? Be specific. This may include providing simple sample tables with values along with a brief description of any calculations needed to answer this question. Note: Since you were not provided with all the values you would need to answer this question, you can make up values to demonstrate how you would arrive at the answer.

How would you then interpret any measures of association you have calculated to determine which food may be the culprit for this outbreak?

Answer 1

First assess the out break of the disease.   In this situation, we will look at four different data collection techniques – observation, questionnaire, interview and focus group discussion – and evaluate their suitability under different circumstances.  Poor and incomplete data collection can lead to a loss of revenue, wasted media dollars, and inaccurate decision making. A lack of quality data causes inability to accurately assess performance, sales, and the converting customer.  

Foodborne diseases are common yet preventable burden of diseases globally . They are acquired by the consumption of food contaminated with toxins, viruses, bacteria or parasites . Though a growing public health concern worldwide because of the associated high levels of morbidity and mortality foodborne diseases are markedly underreported in most countries . This is particularly so in developing countries, where systematic foodborne disease surveillance and epidemiological studies are seldom undertaken

A myriad of aetiologic agents are responsible for foodborne diseases. Clostridium perfringens (C. perfringens) and Salmonella species (Salmonella spp) foodborne diseases are among the commonest foodborne diseases worldwide.worldw they share similar symptoms like diarrhoea and abdominal pain, fever is characteristic of Salmonella infection whilst vomiting is rare in C. perfringens infection. C. perfringens foodborne disease is one of the widespread foodborne diseases documented in industrialized nations and yet underreported because of mild nature and relatively shorter duration of its symptoms . Salmonella spp foodborne diseases share similar characteristics including underreporting, even though they may occasionally cause serious extra-intestinal complications .. When reported, suspected foodborne diseases case-patients are not routinely tested to confirm the offending pathogen or its enterotoxins .

Most foodborne disease outbreak investigations have implicated a single pathogenic organism.However, multi-pathogen related foodborne outbreaks are presumed to be relatively common. Dual pathogen foodborne disease outbreaks linked to Salmonella and Campylobacter species

Laboratory investigations

Before arrival of the investigation team, local health officials had taken stool sample from one of the case-patients to the Eastern Regional Hospital laboratory for analysis. We took stool, throat swab and nasal swab specimens from the affected food handler for laboratory .Samples were transported on appropriate transport media via a triple packaging system to the laboratory within four hours of collection. Samples were tested for enteric pathogens using standard protocols for parasite and bacteria detection.

Most of the leftover food from the food vendor had been discarded. Only stew and “shitor” were available at the food vendor’s premises. We took samples of the leftover food items. We also took water samples from the compound, community water source and the food vendor’s premises. All food and water samples were collected into sterile containers under aseptic conditions and transported on ice packs to the Food and Drugs Authority (FDA), Accra for laboratory analysis using International Organization for Standardization (ISO) methods for specific food items.

Environmental survey

An environmental survey of the wedding place was conducted to assess the general sanitation of the area l. We inspected the kitchen, pantry and dining hall and canteen. We also inspected their places of convenience and refuse disposal sites. We inspected their sources of water.

Surveillance

We assessed the surveillance of foodborne disease and other unusual events in the placet. We evaluated the timeliness of detection and reporting of the cases as well as analysis of the data collected.

Data analysis

We performed descriptive analysis of the outbreak data by person, place and time. Univariable analysis was done by expressing categorical variables as frequencies and relative frequencies. Continuous variables were expressed with appropriate measures of central tendency and dispersion. Based on information obtained from the investigation, we hypothesized that the outbreak was associated with consumption of a particular food item from the food vendor. To test this hypothesis, we conducted a retrospective cohort study where we compared dichotomized qualitative exposure variables (food items eaten) among ill and non-ill who had eaten from the food vendor. We calculated overall attack rate, sex specific attack rates, food specific attack rates and risk ratios (RR). We drew an epidemic curve to show the magnitude and the course of the illness. In bivariable analysis, we calculated the RR and their corresponding 95 % confidence intervals (CIs) associated with consumption of each food item. We determined variables significantly associated with foodborne disease at significance level of 0.05. Variables significantly associated with foodborne disease in the bivariable analysis as well as those found to have yielded pathogens during laboratory analysis were put in a modified Poisson multivariate model with log link using robust error variances to generate adjusted RR and their CIs. Data was analysed using Stata version