VOLUME 4, ISSUE 6

Contact Tracing

Introduction curred, you are much more likely to Imagine that you are a tourist in a find the exposed person. CONTRIBUTORS large city. You have been searching In many communicable disease inves- for a painting by a favorite artist, and tigations, your best source of informa- Authors: you’ve heard that a small gallery tion is the person who might have Michelle Torok, PhD, MPH somewhere in the city is displaying exposed someone else to disease. FOCUS Workgroup* her recent work. But how do you find This type of tracking is called partner this gallery? notification or contact tracing. Reviewers: FOCUS Workgroup* You ask the concierge at your hotel, This issue of FOCUS discusses the who says he has heard of the gallery steps involved in partner notification Production Editors: and knows it is located downtown or contact tracing. This type of investi- Tara P. Rybka, MPH somewhere. You trudge downtown, gation can be very sensitive because but the city is very large, and it often involves discussing intimate Lorraine Alexander, DrPH “downtown” extends for miles. How relationships and diseases such as Rachel A. Wilfert, MD, MPH will you ever find one small artists’ sexually transmitted (STIs), Editor in chief: gallery? Would you start at one end, including HIV/AIDS. and walk up and down every street Pia D.M. MacDonald, PhD, MPH in the downtown area until you stum-

With acknowledgement to Todd Vanhoy bled across it? Of course not. Partner Notification of the North Carolina Department of Instead, you will stop and ask some- Partner notification is “the process of Health and Human Resources’ HIV/STD one to point you in the right direc- locating and notifying partners that Prevention and Care Branch. tion. To get the best directions, you they have been exposed to a dis- will need to seek out someone “in ease.” (1) A partner in an HIV/AIDS * All members of the FOCUS Workgroup are the loop,” someone who knows the investigation, for example, is anyone named on the last page of this issue. area and is familiar with the local art who has engaged in sexual activity or scene. You are more likely to get shared needles with the original pa- useful directions from the owner of tient. another art gallery or a local artists’ guild than from a business person Partner notification is sometimes re- ferred to as contact tracing, which who only comes downtown for work. may be a more appropriate term for The process is similar when you diseases that are spread through non- need to find someone who has been sexual contact, such as exposed to a disease. If you only and other communicable diseases. know that a random person some- where has been exposed, finding The primary purpose of partner notifi- this person will be like looking for a cation is to prevent further transmis- sion of disease. (1) Partner notifica- needle in a haystack. tion for disease prevention has be- The North Carolina Center for Prepared- If, however, you can identify some- ness is funded by Grant/Cooperative Agreement Num- come even more important with the ber U90/CCU424255 from the Centers for Disease one who can tell you who was ex- advent of HIV/AIDS. Control and Prevention. The contents of this publication posed and when the exposure oc- are solely the responsibility of the authors and do not necessarily represent the views of the CDC.

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Other goals of partner notification/contact tracing are: Interviewing Challenges • to educate and treat infected individuals, and • to educate, test, and treat (if needed) individuals Often interviewing is not as straightforward as it may exposed to an infectious disease. sound. Challenging situations the investigator may face include:

• Finding a homeless individual who has no home Use of Partner Notification address, only information about what soup Partner notification is used most commonly for kitchen or shelter he/she frequents. and HIV/AIDS. It can also used for other STIs such as • Finding a prostitute based only on his/her “street and , depending on the resources of name,” physical description, and where he/she the health department. (2,3) usually works. Contact tracing is used routinely for tuberculosis (TB), • Working in dangerous neighborhoods or places and in outbreaks of diseases such as , bacterial (such as crack houses). meningitis, Hepatitis A, and severe acute respiratory syn- drome. Contact tracing systems have also been devel- oped for diseases such as in response to the possibility of a bioterrorist act. (4) abuse treatment centers or prenatal care), and by eliciting partner information from the patient. Partner Notification of Sexually Transmitted Infections Partner elicitation is accomplished by asking the patient Partner notification in STIs is guided by state law. Al- for the names (including nicknames) of sexual and needle- though there are variations in the process depending on sharing partners. For each partner, the interviewer asks for the state, health department, and type of disease, the frequency and dates of exposure, address, phone/beeper CDC recommends the following steps for effective pro- numbers, place of employment, and a physical description. vider referral case management of STIs (1): The interviewer also asks who the partner lives with, where Pre-Interview Analysis the partner hangs out, and whether the partner has been incarcerated. The interview can also provide information The interviewer first reviews available medical and case about other high-risk individuals (called “suspects”) who data to learn the status of the case (new or recurrent), are not partners of the patient but may need medical medical information on the patient, pregnancy status for evaluation. women, and issues unique to the patient such as embar- rassment, sexual orientation, drug use, cooperativeness, The goal is to obtain enough information to find the part- attitude, history of domestic violence, and psychiatric ners and suspects so that the interviewer can provide issues. them with education and risk-reduction counseling and refer them to medical care for testing and treatment, if Based on this information, the interviewer establishes the needed. time during which the patient could have spread the dis- ease to others. This begins with the earliest date the pa- Re-Interview tient could have been infected, and ends with the date of While ideally, all pertinent information is gathered during treatment. The information may be obtained from health the initial interview, a re-interview is often needed to department, physician, hospital, jail, or prison records. gather more partner information, re-emphasize risk reduc- Initial Interview tion and referrals, clarify any illogical statements made by the index patient and elicit additional partners or suspects. The purpose of the initial interview is to prevent further Re-interviews are usually done within several days of the of disease through identification and com- initial interview. munication with the index patient and his or her partner (s). This is done by educating the patient about the seri- Case Closure ousness of the disease and the importance of coopera- A case is closed when the investigator and his or her su- tion, by providing the patient with a risk reduction plan pervisor agree that all reasonable steps to intervene in and appropriate community referrals (such as substance disease transmission have been taken.

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Cluster Interviewing Partner Notification/Contact Tracing of Tuberculosis Another method used in contact tracing/partner notifica- Contact tracing for non-sexually transmitted diseases is tion is cluster interviewing, which expedites the interven- similar to that for STIs. In 2005, the CDC and the Na- tion process when there is not enough partner information tional Tuberculosis Controllers Association published to allow investigators to reach partners individually. Clus- guidelines for TB contact tracing (6), which recommend ter interviews gather information about previously un- that a contact investigation be conducted when a patient named partners or cases and about any persons who has confirmed or suspected pulmonary, laryngeal, or might benefit from a medical examination. This method pleural TB, and a sputum smear or chest radiograph indi- may identify partners whom the case patient is unwilling to cates TB. identify. As with STI partner notification, the first step in a TB con- For example, a syphilis patient may provide limited infor- tact investigation is to gather background information mation about his sexual contacts due to confidentiality about the patient from the medical record, reporting phy- concerns. A cluster interview would attempt to find others sician, or hospital control nurse. This back- at risk by interviewing the patient's partners and suspects ground information can be used to determine the infec- who are not known to be infected. During interviews the tious period for the patient. investigator does not disclose the names of those individu- als who are infected or at risk of infection, but instead con- Interview veys only that syphilis has been diagnosed in the area. The patient interview should occur within 1 business day of reporting for an infectious patient and within 3 busi- The investigator then provides each person with informa- ness days of reporting for a non-infectious patient. If tion about syphilis and encourages the person to get possible, the interview should be conducted in person. tested. The investigator also emphasizes that the person The interviewer gathers information about places where can decrease risk in her social network by offering names disease transmission could have occurred, including the of partners and other high-risk individuals to be similarly patient’s home and congregate settings such as schools, interviewed. Information obtained from cluster interviews nursing homes, correctional facilities, and homeless may be used to determine risk profiles and geographic shelters. locations of target groups for screening. For each place, the patient is asked for names, phone Tuberculosis in a Transgender Network numbers, and addresses of people who may have been In the summer of 1998, the Baltimore City Health Depart- exposed. As you can imagine, depending on the infec- ment was notified of 4 cases of tuberculosis among young tious period of the patient, this can be a time-consuming men. (5) During initial interviews, all the men indicated process. they were part of a transgender social network and partici- It is important for the interviewer to get as much informa- pated in “houses” (social guilds for men who have sex with tion as possible while maintaining rapport with the pa- men and transgender persons). tient. This may mean prioritizing the places of likely dis- Investigators began by conducting a traditional contact ease transmission and possibly following up with another investigation (i.e., identifying close contacts of ill persons) interview. and thus identified 14 contacts. Then, through additional interviewing, investigators developed a profile of people Site Visit participating in the social network. People met the profile By visiting the places of likely disease transmission, the if they had a history of membership in a “house,” had at- investigator may identify additional contacts, including tended specific events, or reported cross-dressing. The children, and determine the likelihood of disease trans- process was similar to cluster interviewing in that the peo- mission. For example, a visit to a homeless shelter will ple identified through the profile were not necessarily allow the investigator to see how many people sleep in close contacts of confirmed TB cases. the same room, how much ventilation there is, whether people eat together in a common area, and whether the Using the profile, the investigators identified an additional 91 contacts. Thus, by employing a combination of tradi- shelter provides screening or other health services. tional contact tracing and social network profiles, the in- Prioritizing Contacts vestigators found 6 additional cases of tuberculosis. Because resources for investigation and follow-up are often limited, the guidelines provide some criteria for prioritizing contacts. The most important criteria are age

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under 5 years and compromised immune status, such as modify the traditional partner notification process. They HIV infection. Secondary criteria are the type of exposure sent notification e-mails to the screen names and re- to the patient and other medical conditions such as diabe- quested a reply. tes. Partners who responded were advised to undergo medical Exposure is classified by the amount of air volume shared evaluation. Through this process of contact tracing, along between the patient and the contact. The smallest with efforts to increase community awareness of the syphi- amount—such as inside a car—indicates a high level of lis cluster, investigators identified 5 additional cases of exposure, while the largest size—any space larger than a syphilis. house—indicates a lower likelihood of exposure.

TB Investigation in Ohio Responsibility for Partner Notification In January 2005, a woman came to the Ashtabula County Depending on the situation and the persons involved, ei- Health Department in Ohio to have a tuberculin skin test ther a public health professional or the patient may notify as part of a pre-employment physical. (7) The skin test partner(s). Generally there are 3 ways to approach partner was positive, and the woman subsequently developed ac- notification: through the health care provider, the patient, tive tuberculosis, as indicated by chest radiograph and a positive sputum smear. Once the patient was diagnosed or contract referral. (9) with active TB, public health nurses interviewed her to ob- Provider Referral tain information about all of her contacts. All of her con- Provider referral occurs when a public health professional tacts tested negative for TB. or health care provider notifies partners of their potential However, additional cases of TB were reported to the disease exposure. This notification is confidential and is health department in March 2005, and contact investiga- done with the consent of the infected person. tion of these patients resulted in more useful information. The son of one of the patients had been experiencing Often a disease intervention specialist, who is a public symptoms consistent with TB for the previous 4 years. health professional specially trained in partner notification, Although various medical professionals had suspected TB, is responsible for partner notification of sexually transmit- none had started the patient on TB treatment or notified ted diseases. However, other persons, such as clinicians or other public health department staff, may also perform the health department about the case. partner notification duties. The complete contact investigation uncovered 6 cases of TB after skin testing of 81 exposed contacts. Without the For TB contact investigations, some health departments investigation, proper treatment would have been delayed have team members devoted exclusively to contact trac- ing, while others employ public health nurses and other for most of the cases. members of multidisciplinary investigation teams. (10) When TB is diagnosed in a hospital, the infection control practitioner or employee health nurse may be involved in Partner Notification in an Outbreak contact tracing. (11) In addition to its importance for routine public health work, partner notification/contact tracing is critical during a pos- Self/Patient Referral sible outbreak because it can identify additional cases Sometimes the patient takes responsibility for notifying his infected with the disease and pinpoint possible sites of or her partners of their potential exposure and referring disease transmission. them to medical care. In such cases, the public health department staff work with the patients to help them pre- San Francisco Syphilis Outbreak pare for the interactions with their partners. In the summer of 1999, the San Francisco Department of Public Health learned of 2 cases of early-stage syphilis. (8) Contract Referral Both patients had met most of their sexual partners in the Contract referral is a combination of self referral and pro- same Internet chat room. vider referral. The patient agrees to notify and to refer to medical care all partners within a certain time period. If When investigators interviewed the patients, they discov- the patient fails to do so, the provider has permission to ered that the patients did not have any identifying informa- tion about many of these sexual partners other than their notify and refer the partners. Internet screen names. This required that investigators

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Training of Investigators local health department, although the list of reportable diseases varies by state. Glossary Training varies depending on the back- ground and job description of the investi- gator. Some receive intensive training Index patient: A patient who through their state health department or Confidentiality is newly diagnosed with a the CDC. Maintaining patient confidentiality about disease and who is a candi- disease status throughout the entire date for an interview. Typi- For example, the CDC has a contact trac- process is imperative. Not only does this cally, the index patient is the ing self-study module. (11) If investiga- promote a trusting relationship between first patient identified in a tion responsibilities include drawing the investigator and the patient, but it is cluster of patients. blood in the field, investigators should be required by law to protect the privacy of trained in Occupational Safety and Health the patient. Administration (OSHA) standards and Partner (in the context of venipuncture. Other aspects of training To this end, investigators should always sexually transmitted infec- may include role playing with practice attempt to interview cases and partners tions including HIV/AIDS): A interviews, HIV counseling and testing, in a private setting. They should try to person who engages in any confidentiality, and hands-on field experi- notify partners face to face and should type of sexual activity or nee- ence with a mentor. never reveal the identity of the original dle sharing activity with the Training is very important because an case to the partner. case. investigator must know how to take sex- Investigators should not leave verbal or ual histories; effectively elicit partners’ written messages for the patient that names; identify and locate contacts; refer mention the disease, nor should they Suspects: Individuals who persons for testing, treatment, and social give confidential information to others are identified as a result of services; and educate and counsel per- such as spouses, friends, or family mem- an interview with an infected sons on high risk behavior. bers. Furthermore, investigation docu- person, but who are not part- mentation is confidential material and ners of that person. Three Moreover, they must be able to apply all must be treated as such. categories of suspects exist: of these skills with individuals who often people with symptoms of the do not trust them, who may not be par- In addition to state and federal confiden- disease, unnamed partners ticularly happy to see them, who are con- tiality laws, each public health depart- of an infected person, and cerned about their confidentiality, and ment has specific confidentiality guide- others who might benefit who may not be motivated to cooperate. lines and legal regulations that investiga- from examination. To do this successfully, the investigator tors are required to follow. must gain the trust of the patient and maintain patient confidentiality. In addition to these interviewing skills, Conclusion the investigator must be familiar with the Contact tracing may be carried out for epidemiology of the disease in question. different infectious diseases such as HIV, syphilis, and TB. It may be done by pro-

vider, patient, or contract referral. Legal Authority for Partner Notification While specific contact tracing procedures The legal authority for partner notification differ by state, the primary goal of con- of sexually transmitted infections resides tact tracing is to intervene in the trans- with the states. (1) The legal authority for mission of an infectious disease. Educa- mandatory disease reporting is derived tion, testing, and treatment are addi- from state law (12), and states may have tional goals of contact tracing. slightly different organizational structures and approaches to partner notification depending on their state laws. All 50 states require that certain diseases be reported to the appropriate state or

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REFERENCES: CONTACT US: 1. Centers for Disease Control and Prevention. Program operations guidelines for STD prevention: Partner services. Available at: http:// www.cdc.gov/std/program/partners.pdf. Accessed September 26, The North Carolina Center for Public Health Preparedness 2007. The University of North Carolina at Chapel Hill 2. Hogben M. Partner notification for sexually transmitted diseases. Clinl Campus Box 8165 Infect Dis. 2007;44(suppl 3):S160-S174. Chapel Hill, NC 27599-8165 3. Golden MR, Hogben M, Handsfield HH, St. Lawrence JS, Potterat JJ, Holmes KK. Partner notification for HIV and STD in the United States: Phone: 919-843-5561 Low coverage for gonorrhea, chlamydial infection, and HIV. Sex Trans Dis. 2003;30:490-496. Fax: 919-843-5563 Email: [email protected] 4. Centers for Disease Control and Prevention. Smallpox response plan and guidelines (version 3.0). Available at: http://www.bt.cdc.gov/ agent/smallpox/response-plan/index.asp. Accessed October 25, 2007. 5. Centers for Disease Control and Prevention. Cluster of HIV-infected FOCUS Workgroup: adolescents and young adults – Mississippi, 1999. MMWR Morb • Lorraine Alexander, DrPH Mortal Wkly Rep. 2000;49:861-864. • Meredith Anderson, MPH 6. Centers for Disease Control and Prevention. Guidelines for the • Lauren N. Bradley, MHS investigation of contacts of persons with infectious tuberculosis. • Anjum Hajat, MPH MMWR Recomm Rep. 2005;54:1-43. • Pia D.M. MacDonald, PhD, MPH 7. Kettunen CM, Sunmonu Y, Hodgkinson AL, et al. Contact investigation • Gloria C. Mejia, DDS, MPH of a case of active tuberculosis in the community. Am J Infect Control. • Amy Nelson, PhD, MPH 2007;35:421-424. • Tara P. Rybka, MPH 8. Klausner JD, Wolf W, Fischer-Ponce L, Zolt I, Katz MH. Tracing a syphilis • Rachel A. Wilfert, MD, MPH outbreak through cyberspace. JAMA. 2000;284:447-449. 9. Macke BA, Maher JE. Partner notification in the United States: An evidence-based review. Am J Prev Med. 1999; 17:230-242. 10. Wilce M, Shrestha-Kuwahara R, Taylor Z, Qualls N, Marks S. Tuberculosis contact investigation policies,practices and challenges in 11 U.S. Communities. J Public Health Manag Pract. 2002;8:69-78. 11. Centers for Disease Control and Prevention. Self-study modules on If you would like to receive electronic copies of tuberculosis. Module 6: Contact investigations for tuberculosis. FOCUS on Field Epidemiology, please fill out the Available at: http://www.cdc.gov/tb/pubs/ssmodules/module6/ form below: ss6contents.htm. Accessed September 26, 2007. • NAME: 12. Teutsch SM, Churchill RE, eds. Principles and Practice of Public Health ______Surveillance. New York, NY: Oxford University Press; 2000. • DEGREE (S): ______UPCOMING TOPICS! • AFFILIATION: ______

• E-MAIL ADDRESS: ______• Biosafety Levels • May we e-mail any of your colleagues? If so, please include their e-mail addresses here: • Risk Communication ______• Minority Considerations ______Please fax to: (919) 919-843-5563 We are on the web! or mail to: North Carolina Center for Public Health Preparedness http://www.sph.unc.edu/nccphp The University of North Carolina at Chapel Hill Campus Box 8165

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