February 24, 2006
Epi Update Managing Staff:
"The reason for collecting, analyzing and disseminating information on a disease is to control that disease. Collection and analysis should not be allowed to consume resources if action does not follow."
Foege WH., International
Journal of Epidemiology 1976; 5:29-37
A retrospective cohort study was initiated. A questionnaire was developed based on the menu items served. A list of employees who had attended the luncheon was obtained. Interviews of both ill and non-ill attendees were conducted. A case was defined as an employee who had attended the luncheon and became ill with nausea, diarrhea, abdominal cramps, and/or vomiting within 12 hours following the luncheon. Analysis of data collected was performed using Epi-Info 2000.
“Employee observed on serving line grabbing cooked food with bare hands to put on plate. Employees observed not properly changing gloves and/or washing hands, e.g., employee observed handling raw salmon with gloved hand and headed back to line started to grab cooked food, employee observed scratching face and ears with gloved hand and did not switch gloves and wash hands. Employees observed wiping gloved hands and utensils on soiled aprons, rags without washing hands. Employees observed improperly washing/rinsing hands in 2-compartment sink. Food-contact surfaces not being properly cleaned and sanitized after being contaminated, e.g., meat slicer and veggie mixer. Observed improper use of wiping clothes/rags without the use of sanitizer buckets. Observed utensils being improperly washed. Produce observed stored on the floor. Some hand wash sinks missing either soap or hand drying devices.”
A total of 11 probable cases (16.4%) out of 67 attendees who responded to the questionnaire matched the case definition. Ages ranged from 25 to 61 years, with an average age of 40 years. Approximately 91% of the cases were female. Onset of illness ranged from 30 min to 10 ½ hours after consuming the meal, with an average incubation period of 4 hours. Chart 1 displays the epi curve for the suspected outbreak.
Frequency of symptoms are summarized in Table 1. Duration of symptoms ranged from 2 minutes to 72 hours, with an average duration of 24 hours.
Food specific attack rates, relative risks, 95% confidence intervals, and p-values were calculated for all food items served at the luncheon. Table 2 represents the results of analysis of the data for food items found to be statistically significant. Employees who consumed red snapper at the luncheon were at most risk for becoming ill.
The following food process was obtained from the chef for the red snapper entrée:
“Red snapper was Philip’s Brand and received from Sysco Foods in frozen boxes. The snapper is individually pre-packaged. Once received, it is stored in the freezer in the original boxes until ready for preparation. On the date of the luncheon, the snapper was prepared and cooked from a frozen state. Salt, pepper, and dry dill were added as seasoning to the snapper along with an herb butter sauce made of butter, white wine, heavy cream, and fresh dill. It was cooked in the oven at 375 F for approximately 20 minutes.”
Cases were no longer symptomatic at the time the interviews were performed and none of the patient cases sought medical care for their illness. No clinical samples were available for laboratory analysis.
No etiologic agent was linked to the suspected outbreak since no food samples and/or clinical samples were available for testing. Based on the short incubation times, however, it appears that the agent involved was most likely a toxin such as Staphylococcal enterotoxin or Bacillus cereus enterotoxin. Since diarrhea was as prominent a symptom as vomiting, Bacillus cereus enterotoxin appears to be the most likely agent. Infections related to viruses, bacteria and parasites generally tend to have longer incubation periods.
The implicated food appears to be red snapper. It was found to be the most statistically significant food item (95% CI – 1.56 – 28.49, p = 0.0031175) and has the highest calculated relative risk (6.67). Some possible explanations as to why not all people who consumed the red snapper became ill include the organism or toxin which produced the illness was not evenly distributed in the snapper, causing some people to ingest smaller doses and/or some people who ate the snapper may have eaten a smaller quantity and/or some people who ate the snapper may have been more resistant to the illness. Possible explanations as to why some cases that did not consume the snapper became ill include: their food may have been cross- contaminated based on environmental investigation results and/or they may have become ill from something else.
Water and coffee were also found to be statistically significant and have high relative risks, however, do not appear to be the implicated food item. This is based on several reasons: The golf club restaurant also prepares food and drinks for the general public. No other illness complaints were received from the golf club restaurant. Also, the golf club restaurant is on a municipal water system. Red snapper was served only at the catered luncheon while coffee and water were served at both the catered luncheon and to the general public.
Association of Food Protection. Procedures to Investigate Foodborne
Illness. 5th edition. 1999.
Epidemiology Grand Rounds
Hurricane Mortality in Florida
The objectives of this study were to 1) describe the hurricane-related mortality associated with each storm, as well as the overall hurricane season mortality for 2004 and 2005, 2) accurately characterize the hurricane-related deaths and, 3) based on these findings, identify strategies to prevent or reduce direct and indirect future hurricane deaths.
Most hurricane- related deaths are due to unintentional injury and therefore, preventable. Prevention messages should target high-risk, post-impact activities, particularly motor vehicle use, clean-up activities, generator use, and electrical power outages/restoration.
Patti Ragan is an EIS fellow currently assigned to the Bay County Health Department. She can be reached via telephone at 850.872.4720.
Bureau of Epidemiology / CHD
On February 10, 2006, Bureau of Epidemiology staff and personnel at county health departments throughout the state met on conference call to discuss and review a variety of issues pertaining to mutual interests. The following excerpts are highlights of this meeting.
Upcoming events. Dr. Dian Sharma reminded CHD directors and administrators to register now, if they haven't done so already, for the leadership workshop on pandemic influenza scheduled for February 20 in Tampa. This is a one-day event designed for decision-makers tasked with planning for pandemic emergency operations. She also noted that the governor's summit on pandemic influenza, entitled Florida's Pandemic Readiness and Emergency Planning Summit, scheduled for February 16, will be held at the Tallahassee Civic Center and include speakers from CDC and the Department of Homeland Security.
Florida Epidemic Intelligence Service Update. Alan Rowan announced seven openings for this year's class of EIS fellows. Applications from CHDs must be received by March 3 and should include project outlines and a mentor name. Salary for each fellow is paid by the Bureau of Epidemiology. For more information about this program, contact Dr. Rowan at 850.245.4404.
CHD After-hours Accessibility and Drills. Rick Clark reminded participants that the goal of the exercise is to assess how quickly health department personnel can respond to his calls. Using the after-hours number published in a local telephone book, he phones to make a report of illness to the on-call physician or nurse authorized to take an epi case report. These calls are followed by a courtesy letter describing the results of his test.
Merlin Update. Janet Hamilton revealed that IT will be testing the Merlin disaster recovery system on February 22. A message will be disseminated prior to the test, which is being performed to ensure Merlin can function during a natural disaster.
Legionellosis in Volusia. Andre Ourso provided an update on the Legionellosis and pneumonia cluster found at a Volusia County hotel. Eight guests and one hotel maintenance worker were confirmed with Legionella. One death occurred on January 28. Three of the patient cases were vacationers from other states. The case definition has changed at this point of the investigation. High fever is a common symptom in the cases, and so are weakness and fatigue. Susie Grubbs added that her environmental investigation uncovered the fact that the hotel had no main backflow device installed by the city. The city has since sent engineers to address the problem. Media communications have been positive throughout the investigation, and the public has been well briefed on the illness.
Influenza in Brevard County. Barry Inman reported that the Brevard CHD was notified on February 3 by a long-term care facility that two patients had tested positive for influenza, and nine patients and five staff members were experiencing ILI. After investigating, his team determined that 10% of the patients had not been immunized prior to flu season. The investigators ensured all residents were administered Tamiflu and prophylaxed the others. It appears infection control surveillance procedures were not begun until after the outbreak started, so Inman is working with the medical director to implement these procedures permanently. The outbreak seems to be waning.
Suspected Pertussis in Miami-Dade. Dr. Fermin Leguen apprised the listeners of a call Marie Etienne received from the Miami-Dade Firefighters Wellness Center, which reported >30 cases of cough and ILI. There are approximately 1500 firefighters listed with the center. The center staff suspect 39 cases of Pertussis but none are confirmed. Dr. Fermin and his team are awaiting lab results and are still interviewing patient cases but he has cautioned that the only acceptable tests for Pertussis are cultures and PCRs. He believes the outbreak began in mid-December 2005 and is waning at this time. The surveillance manual includes new medications and guidelines and notes that Pertussis is a reportable disease in Florida.
Training Update. Melanie Black stated that this year's statewide epidemiology seminar will be held May 16-17 at the Doubletree Hotel at Universal Studios. There will be no registration fee. More details will follow.
The topic for March grand rounds is rapids needs assessment in Broward and Hendry counties. The presenters will be Nicole Basta and Sharlene Emmanuel, both EIS fellows. The event is scheduled for March 28.
A satellite broadcast on pandemic influenza 101 will be shown on March 8, with Nancy Humbert moderating. CEUs will be given.
The next regional training workshop will be held in late April or early
May in West Palm Beach. The workshop will be structured differently from
past trainings, with the program divided into basic, intermediate and
possibly advanced modules. Log on to the training page of the Bureau
of Epidemiology Internet site for more information as it becomes
Pre-Exposure Titer or Antemortem Evaluation
by JoEllen DeThomasis, MPH; Carina Blackmore, DVM, PhD; Lisa Conti, DVM, MPH
In March 2001 an Epi Update was published regarding the circulation of ELISA tests for human rabies. Since that time, questions continue to be raised about the recommended use of these tests. This article is being reissued to reiterate the importance of the original notification that these tests are NOT recommended for use in Florida.
Rabies preexposure vaccine is recommended for:
1) all persons at occupational risk for infection with rabies virus either by aerosol, injection or animal exposure; and
2) persons traveling extensively in foreign countries where rabies is endemic. High-risk occupational groups include veterinarians, veterinary students, veterinary hospital employees, animal control officers, wildlife workers, wildlife rehabilitators and animal handlers in zoological parks and exhibits.
People involved in disaster animal response may consider being preimmunized if their expected frequency of animal contact is elevated (criteria 1, above). Persons most at risk for accidental infection work with live rabies virus in diagnostic and research laboratories and in vaccine facilities. CHDs will administer the vaccine at the expense of the vaccinee.
Immunized individuals at occupational risk for exposure should check serologic titers semiannually. The rapid fluorescent-focus inhibition test (RFFIT) is the recognized test for determining rabies titers. Titers less than 1:5 serum dilution indicate the need for an intramuscular booster vaccination. Please see the Florida guidebook http://www.doh.state.fl.us/disease_ctrl/epi/htopics/popups/rabies.htm for more information.
Pasteur or Quest ELISA kits for rabies antibody titer determination are NOT FDA APPROVED and are considered "home brew" tests. Any lab performing rabies ELISA testing is required to put a disclaimer on the test result sheet stating that it is not an FDA-approved test. Unfortunately, the FDA does not restrict these labs from conducting the test. In addition, this test is NOT APPROPRIATE for rabies antemortem determination. In the past, the diagnosis of human rabies was inappropriately considered for a Florida patient based on serology from this testing. Obviously, the human and veterinary public health ramifications resulting from this type of improper testing can be quite broad.
CHDs and physicians wanting to submit human diagnostic specimens for rabies are required by the CDC to contact the Division of Environmental Health at 850.245.4732 prior to shipment to the CDC Rabies Laboratory.
The authors are staff at the Division of Environmental Health and can be reached at 850.245.4250, or log on to the division website at http://www.doh.state.fl.us/environment/index.html.AG Holley Presents
Special Lecture Series
by Jaime Forth
At a guest lecture series co-sponsored by the Florida AHEC Network and Everglades Area Health Education Center, Lee B. Reichman, MD, executive director of the National Tuberculosis Center at the New Jersey Medical School will present a course entitled "The Most Widely Misunderstood Diagnostic Test of All" at AG Holley State Hospital on March 15, 2006.
The lecture will begin at 11:00 a.m. and include an explanation of the role and limitations of the Mantoux TB test, an examination of the epidemiology of latent tuberculosis infection (LTBI), and a list of treatments for LBTI and its indications/limitations.
Continuing education credits will be issued for those in attendance. For more information, call Affette McIntosh at 561.582.5666.
During the period February 12-18, 2006, the following arboviral activity (St. Louis encephalitis [SLE] virus, eastern equine encephalitis [EEE] virus, Highlands J [HJ] virus, West Nile [WN] virus, California Group [CAL] virus and dengue virus) was recorded in Florida:
Wild Live Captive Birds: Three wild birds out of 10 captured on 2/8/06, and one out of 20 captured on 2/9/06 in Okaloosa County tested positive for antibodies to EEE virus.
Mosquito Pools: None
See the web page for more information at www.MyFloridaEH.com. The Disease Outbreak Information Hotline offers recorded updates on medical alerts status and surveillance at 888.880.5782.
The Bureau of Epidemiology encourages
Epi Update readers to not only register on the EpiCom system at
https://www.epicomfl.net but to sign up for features such as automatic
notification of certain events
contribute appropriate public health observations related
any suspicious or unusual occurrences or circumstances. EpiCom is the primary method of communication
between the Bureau of Epidemiology and other state medical agencies during emergency situations.
Christie Luce is administrator
of the Surveillance Systems Section in the Bureau of
Epidemiology. She can be reached at 850.245.4444, ext. 2450.
Click here to review the most recent disease figures provided by the Florida Department of Health Bureau of Epidemiology.
D'Juan Harris is a GIS
specialist in the Surveillance Systems Section of the Bureau of
Copyright©2006 State of Florida