I ll begin the third section of the Services to Prevent and Control Communicable Disease Orientation Module on Epidemiology Investigations.

Transcription

1 I ll begin the third section of the Services to Prevent and Control Communicable Disease Orientation Module on Epidemiology Investigations. After completing this module section, participants will be able to understand the different reporting requirements between a Category I, Category II, and Category III Communicable Disease, identify the legislative mandates for communicable disease investigation, and describe how to conduct an epidemiologic investigation of a communicable disease. 1

2 Category 1 communicable diseases are of urgent public health importance and must be reported immediately to the patient's local health officer upon identification of a case or a suspected case being tested by a medical provider. While the statute states local health officer, the local health department determines who accepts the call and it is usually the communicable disease nurse or the intake nurse. Laboratories are also required to report cases or suspect cases according to Wisconsin Statute 252. How else could the local health department be notified of Category I Communicable Diseases by a parent or guardian, WEDSS, State immunization program, school, day care center, employee, community members, or others. The following slides contain a list of category 2 reportable diseases. The majority of reportable diseases in Wisconsin are Category 2. 2

3 Category 2 requires reporters to notify the local health department within 72 hours of identification of a case or a suspected case. The Category 2 diseases are not as urgent a public health problem as category 1 diseases. 3

4 Category 3 communicable diseases are unique. The category 3 diseases are HIV and AIDS, and rather than reporting to the local health department, they are reported directly to the state epidemiologist for follow-up by the AIDS/HIV program. Once investigated, the state AIDS/HIV program refers the person back to the local health department for partner contact investigation and testing. This is accomplished through the Partner Counseling and Referral Services program, or, PCRS. Local health departments have staff designated to perform PCRS because it requires intensive initial training and on-going required trainings. In most agencies, one person is assigned to PCRS as most agencies do not have many cases to follow up with. Now we are going to see how the communicable disease control concepts work together. We will be looking at a Pertussis case study to demonstrate this. It s 9:00 AM on a Tuesday morning. You are the public health nurse taking communicable disease calls for the day. You receive a phone call from a school secretary because a child s parent called and said the child will not be in school today because he has pertussis. Why did the school secretary call this pertussis case to the local health department? Per Wisconsin Statute 252, if a teacher, school nurse, or principal of any school or day care center knows or suspects that a communicable disease is present in the school or center, he or she must immediately notify the local health officer. 4

5 Before you begin the investigation, you will want to learn more about Pertussis. You will remember that two good resources are the EpiNet and the Control of Communicable Disease manual. The Department of Health Services publishes communicable disease fact sheets available to the general public. The more common disease fact sheets are available in Spanish and Hmong as well as English. 5

6 Wednesday, the following day, the medical provider calls you and confirms the child has pertussis. Now we will talk about how the Public Health Nurse applies epidemiologic concepts throughout a disease investigation. The natural history of disease is the process by which diseases occur and progress in the human host. This process involves the interaction of three different kinds of factors, the causative agent, a susceptible host, and the environment. As long as a state of equilibrium exists between the host, agent, and environment, a state of health is maintained. A disequilibrium increases the likelihood of a susceptible host being exposed and developing the disease. This is called the epidemiology triangle. The three components of the epidemiology triangle are: The Agent, which is a factor whose presence is essential for the occurrence of a disease. Agents can be physical such as temperature, chemical such as gases, nutrient such as protein, genetic transferred through genes, psychological such as stress, or biological such as bacteria. The Host is the individual in whom an agent produces disease. The Environment is all external conditions and influences affecting life of living things. The three main categories of environment are physical, biological, and socioeconomic. 6

7 How do we determine this was a case? The Division of Public Health defines a confirmed Pertussis case as: 1) An illness in a person with an acute cough of any duration who is culture positive this is the host 2) A case that meets the clinical case definition and is confirmed by PCR--this is the agent 3) and, a case that meets the clinical case definition and is epidemiologically linked directly to a case confirmed by either culture or PCR--this is the environment. The recommendations for follow-up can be found in the materials noted on this screen. While these resources are focused on pertussis, similar materials are available for all reportable communicable diseases. Other sources of information to guide you through the process of case investigation include a regional immunization and public health nurse consultant available in each regional office, the WI State Lab of Hygiene, the Regional Preparedness Consortium Epidemiologist, and legal resources regarding isolation and quarantine. 7

8 Disease and health event investigation can be defined as: systematically gathering and analyzing data regarding threats to the health of populations, ascertaining the sources of the threat, identifying cases and others at risk, and determining control measures. Let s talk about the basic steps for disease and other health event investigation. First, define the problem. Correctly identify the disease and its source. In our case study, this would be pertussis. Defining the problem may require gathering data from multiple sources to understand the etiology, natural course, and expected sequella. Next, establish clear criteria for what constitutes a case. Consider the existing data. This includes primary data, such as the lab report and secondary data, such as the school secretary report. Determine what is currently known about the identified cases in terms of person, place, and time. For person - identify who and how many people are affected. Who else might be affected? Is there a connection between the people affected and their age, sex, race, and socioeconomic status? For place - think about whether it matters where people live or work? Are the cases limited to certain areas or widely dispersed? Does the area naturally harbor certain disease agents? For time - ask whether the time of day or association with a specific event, such as weather conditions, appear to make a difference? 8

9 Now you can generate and analyze data using appropriate scientific and epidemiologic principals. Depending on the nature of the suspected disease or event, this may include use of: direct observation or collection of clinical data such as: interviewing cases performing physical assessments collecting specimens or reviewing available lab data Specific interview and assessment protocols are often used to assure consistency in data gathering. For our pertussis investigation, this would include the standard Pertussis Reporting Form and the Communicable Disease Reporting Form, the Next, you determine, based on the analysis, what factors are likely to cause the problem or risk. Arriving at an accurate conclusion requires careful and thorough consideration; be as sure as possible. Accuracy may be enhanced by: reviewing and comparing reports from previous similar investigations conferring with others involved in the investigation sharing and comparing data carrying out secondary data collection to confirm suspicions. The next step is to determine and communicate an appropriate response. Based on the analysis and conclusions about the problem, its causes, and the conditions in which it occurs, offer options for prevention. First, consider primary prevention options, then secondary prevention options, if primary is not feasible, and finally, tertiary prevention if neither primary or secondary prevention is possible. Referral and follow up should be provided for those in need of treatment. Finally, evaluate the effectiveness of any action taken. Determine the extent to which the problem or risk was eliminated or prevented. Calculate the resources required and areas where greater efficiencies could be achieved to guide your future practice. 9

10 Case finding is the only public health interventions on the Public Health Intervention Model that is done strictly at the individual or family level. The basic steps in case finding are: 1. Identify those individuals and families at particular risk through information from surveillance, disease and health event investigation, and/or outreach. In our example of pertussis, the public health nurse would do case finding by asking the child or the parent who they sit next to in school, play with, attend religious classes with, or play sports with. Risk severity is intensified by factors that make individuals and families unaware, unable, or unwilling to respond. An individual and family may be unaware of the risk because they may be isolated from the media, for example, by not subscribing to local newspapers in which the local public health department has a news release about the increase in pertussis in the community. They may be unable to respond because there is a language barrier. Or, they may be unwilling to respond due to their dislike of the governmental system. 2. Connect with formal and informal networks to find those identified as at-risk. In the case of pertussis, it is important to maintain strong ties with your community partners as well as develop a trusting relationship with the individual and family. Keeping the medical community, the school system, human service agencies, and other neighboring health departments abreast of the pertussis situation in your jurisdiction is vital for communicable disease control. In addition, by developing trusting relationships with the individual and family, the likelihood of compliance with the treatment regimen is more likely. 3. Initiate activities to provide information about the nature of the risk, what can be done about it, and how services can be obtained. This is accomplished through the related public health interventions of health teaching and counseling to increase the knowledge of the individual and family about the potential for harm. If the individual and family are facing barriers to treatment, the PHN may need to use the public health interventions of advocacy, consultation, or referral and follow-up to help the individual and family resolve the barriers. 10

11 4. If the level of risk suggests endangerment to the individual, family, or community, the PHN should provide direct access to necessary services. For example, if the PHN discovers a symptomatic individual cannot be tested due to transportation problems or other barriers, the PHN may need to obtain the NP swab to test for pertussis, under the direction of the agency medical advisor, and submit the sample to the WI State Lab of Hygiene for testing to assure care. 5. Fulfill all reporting requirements mandated by state laws and regulations, such as those regarding reportable contagious diseases or child maltreatment. The Standard Communicable Disease Reporting Form, the 4151, and the Pertussis Reporting Form are required in Wisconsin. Surveillance can be defined as that which: describes and monitors health events through ongoing and systematic collection, analysis, and interpretation of health data for the purpose of planning, implementing, and evaluating public health interventions. 11

12 The basic steps of surveillance the public health nurse may consider with a pertussis case are: 1. Determine whether surveillance is appropriate for the circumstances. In the case of pertussis, working with the school nurse to determine the immunization status of the children in the case s classroom is important to prevent further spread. While a school age child may not seem too sick, pertussis could be deadly to an infant sibling, or a child in the classroom who has respiratory compromise. 2. Acquiring the necessary knowledge of the problem, its natural course, and its aftermath. The public health nurse would need to be aware of the incubation period of pertussis, the communicability time, what constitutes an exposure, and duration of symptoms. 3. Establishing clear criteria of what is a case. For pertussis, the guidelines define a probable case, confirmed case, and suspect case based on exposure, symptoms, and duration. 4. Collect sufficient data from multiple valid sources. For our pertussis case, this would include interviewing a parent or guardian, the medical provider, and possibly the school nurse, to find out the school layout and classroom processes. 5. Analyze data using appropriate scientific and epidemiologic principals, including number of cases, contacts, description of population affected, where it is occurring, and the period of time over which it occurred. 6. Interpret and disseminate the data in such a way that decision makers at all levels can readily identify and understand the implications. Examples of this step include working collaboratively with the school nurse and principal to develop health information for classrooms, sports teams, and religious classes. It may also include providing informational letters to health care providers in the area and possible media releases. 7. Evaluate the impact of the surveillance system. Was enough data collected to support accurate analysis? Did it generate answers to the problem? Was the information timely? Was it useful? How was it used? How could it be made of greater use? Did it identify any weaknesses in the system that need to be addressed? One step of the surveillance intervention mentioned was working collaboratively with the school nurse to review immunization status of the classroom and school. The School Immunization law was discussed earlier and obtains its authority from WI Statute Ch The purpose of the statute is to eliminate vaccine preventable diseases. Students in elementary, middle, junior, or senior high schools, day care or nursery schools, have 30 school days to 12

13 present written evidence that they are immunized for the required diseases. Requirements can be waived if the student s parent, or the student, if they are an adult, submits a written statement that they object to the immunizations based on health, religious, or personal conviction. If the student does not provide evidence of immunization or waiver upon admission, the parent or guardian is notified per letter on the 15th day and the 25th school day that they are not in compliance. If fewer than 99% of the students in the day care or school meet the requirements, the unimmunized student can be excluded from school. If after 60 days from the start of school, the student has not provided evidence of immunization or a waiver, the school or day care center must notify the district attorney. The district attorney petitions the court exercising jurisdiction for an order directing the student to be in compliance. If the adult student or parent/guardian refuses to provide a written waiver or receive the vaccines, they can be fined $25.00 per day of violation. What happens if the student signs a waiver and there is an outbreak of a vaccine preventable disease such as pertussis? Under WI Statute Ch , the school has the authority to exclude the student until the outbreak subsides. More details are available in HFS 144. While public health departments are privilege to health information about communicable diseases in their jurisdiction, caution must be exercised to assure confidentiality for the case and family. It is important to exchange information with those involved in the health care of the case, but the sharing of information should be restricted to those who need to know to prevent the spread of communicable disease, not those who are just interested. Administrative Rule HFS reminds us that All information provided under this subsection shall remain confidential except as may be needed for the purposes of investigation, control, and prevention of communicable diseases. 13

14 Confidentiality of health information and protecting the public's health can cause confusion, delay treatment, and produce barriers to continuity of care. HIPAA, the Health Information Portability and Accountability Act, specifically addresses the use of health information for public health agencies: The HIPAA Privacy Rule lists the uses and disclosures for which consent, authorization, or opportunity to agree or object is not required. One of the uses listed, is the disclosure of protected health information to the extent that such use or disclosure is required by law and the use or disclosure complies with and is limited to the relevant requirements of such law. This section also authorizes uses and disclosures for public health activities as stated on this slide. In addition, Wisconsin statutes states: Any health care provider who knows or has reason to believe that a person treated or visited by him or her has a communicable disease, or having a communicable disease, has died, shall report the appearance of the communicable disease or the death to the local health officer. The statute also lists the types of information that reports shall include: Name, sex, age, residence, the communicable disease, and other facts the local health officer requires. Isolation and quarantine are words that are often used interchangeably and incorrectly. It is important to remember that we isolate the ill, and quarantine the well. 14

15 Isolation is separation, for the period of communicability, of an infected person from others in such places and under such conditions as will prevent the direct or indirect transmission of an infectious agent to susceptible people who may spread agents to others. For example, a person is isolated at home for five days after initiating medication for pertussis to prevent spreading it to others. Quarantine is restricting the freedom of movement of a well person or domestic animals who have been exposed to a communicable disease for a period of time relating to the usual incubation period of the disease, in order to prevent contact with those exposed. For example, a dog vaccinated for rabies may be placed in quarantine for 10 days after biting someone to assure the dog does not develop sign of rabies infection. In Wisconsin Statute Ch , the local health officer can require the isolation of an individual suspected of having a communicable disease and the quarantine of contacts if needed. The most common communicable diseases that require isolation in Wisconsin are pertussis and tuberculosis. Most of the time, the isolation is voluntary. However, if the individual is not cooperating with the isolation request, the health officer can petition the court for confinement orders. The health officer also has the authority under this statute to employ and swear in quarantine guards who have police powers, and may use all means necessary to enforce state laws for the prevention and control of communicable diseases or the orders and rules of the department or any local health officer. Isolation and quarantine can be expensive--the county is responsible for employing quarantine guards, maintaining isolation and quarantine and enforcing isolation of the quarantined area, conducting exams and tests for disease carriers made under the direction of the local health officer, and care provided to any dependent person. Additionally, assuring isolation in the least restrictive environment is often a challenge that requires critical appraisal. The picture on the slide is from New immigrants to the country were held in quarantine detention at the Immigration Station on Ellis Island, New York. Those suspected of having a communicable disease were segregated at once and, after confirmation of the diagnosis, admitted to the communicable disease hospital for care and treatment. 15

16 Personal Protective Equipment, or PPE, is any type of specialized clothing, barrier product, or breathing device used to protect workers from serious injuries or illnesses while doing their jobs. Proper use of PPE by workers involved in patient care aids infection control because it helps protect wearers against infection or contamination from blood, body fluids, or respiratory secretions; reduces the chance that healthcare workers will infect or contaminate patients or coworkers; and reduces the chance of transmitting infections from one person to another. PPE may also be used by workers in public health settings to help protect against certain biological agents or other environmental hazards. OSHA requires the use of personal protective equipment (PPE) to reduce employee exposure to hazards when engineering and administrative controls are not feasible or effective in reducing these exposures to acceptable levels. Employers are required to determine if PPE should be used to protect their workers. If PPE is to be used, a PPE program should be implemented. This program should address the hazards present; the selection, maintenance, and use of PPE; the training of employees; and monitoring of the program to ensure its ongoing effectiveness. Your agency should have a policy available for you to review regarding PPE. It is important to note that PPE is not a substitute for good engineering, work practice, and administrative controls, but should be used in conjunction with these controls to provide for a safe and healthy workplace. 16

17 Let s conclude our pertussis case example. It is now six weeks later. The pertussis case was contained to the one child without further known spread to friends, classmates, or families. Let s take a few minutes to review the public health interventions you, the public health nurse, utilized to prevent the spread of this communicable disease. 1. Disease & Health Event Investigation. From the time the case was called in by the school secretary, the PHN defined the problem, established clear criteria for what constituted a case, considered existing data, generated and analyzed additional data, determined the cause and risk of the problem and communicated an appropriate response. 2. Surveillance: The PHN acquired the necessary knowledge of the problem, pertussis, its natural course, and its aftermath. This included utilizing established, pertinent resources as well as becoming familiar with the isolation and quarantine laws in Wisconsin. In addition, by working with the school nurse to analyze the immunization status of the children in the classroom, the PHN became knowledgeable about the state statutes that direct the school immunization law. 3. Case finding: By following up with the contacts of the case, the PHN utilized case finding to find additional cases or persons at risk of becoming cases. This intervention is almost always directed at the individual/system level of practice. 4. Referral and Follow-up: The PHN provided referral and follow-up for the individuals who did not know how to access the medical system. In this example, this intervention is targeted at the individual or system level. 5. Delegated Functions: The PHN performed a delegated function when obtaining a NP swab on a symptomatic individual who could not access health care due to transportation and other barriers. As case finding and referral and follow-up, this intervention is directed at the individual or family level. 6. Health Teaching, probably the number one intervention utilized by public health nurses, the PHN provided health teaching to the individual and family of the case about the cause, communicability, treatment regimen, and complications associated with pertussis. This was done through multiple means including verbal instructions, fact sheets, and possibly internet resources at the individual or family level 7. Counseling: The PHN may have provided counseling to the family of an unimmunized child in the classroom regarding the options available for the child to stay healthy. This intervention is directed to the individual/family level. 17

18 8. Consultation: The PHN consulted with the regional immunization consultant about what children should be prophylactically treated in the classroom and with the medical provider about the family members who should be treated. This is an example of an intervention at the systems level. 9. Advocacy--The PHN advocates for those who cannot access care due to barriers in the health care system. While this demonstrates an intervention at the individual/family level, by addressing the barriers with the health care provider it is targeting the systems level. 10. Policy Development and enforcement. The PHN enforces the isolation requirements of the child who has pertussis and possibly excluding a child who may be unimmunized, which target the individual/family level of interventions. While it appears that most of the interventions the PHN did with this pertussis case focused on the individual/family level, it is important to remember that the interventions are all population based, working within a subgroup of the population, those at risk for pertussis. What makes these interventions population based is that they: 1. Focus on an entire population possessing similar health concerns or characteristics, for example, those at risk for pertussis. 2. They are guided by an assessment of population health status, determined by the disease surveillance. 3. Consider the broad determinants of health, such as those who can and who cannot access health care for treatment or prophylaxis. 4. Consider all levels of prevention with a preference for primary prevention. Immunizations are primary preventions and would be the first line of defense PHN s assess for. Prophylaxing those who have been exposed but are not ill could be secondary prevention, and treating the case with the appropriate antibiotics is tertiary prevention. 5. The interventions consider all levels of practice, individual, family, community, and systems. 18

19 The phone number on this slide can be used to call the Department of Health Services 24 hours a day if you have questions about communicable disease, chemical incidents or spills, natural disasters, or radiological/nuclear incidents. This is a good transition to the next part of the presentation, the role of the public health nurse in emergency preparedness. 19