Transcript Contact Tracing - UNC Center for Public Health Preparedness

Contact Tracing
Goals
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Discuss the steps involved in partner
notification or contact tracing
Finding a Needle in a Haystack
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You need to find someone who has
been exposed to a disease
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Only know that a random person
somewhere has been exposed
Identify someone who can tell you who
was exposed and when exposure occurred
Your best source of information is
person who exposed someone else to
disease
Partner Notification
or Contact Tracing
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Can be very sensitive
Often involves discussing intimate
relationships and diseases
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Sexually transmitted infections (STIs)
Including HIV/AIDS
Partner Notification
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“The process of locating and notifying
partners that they have been exposed to a
disease”
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Partner in HIV/AIDS investigation: anyone who
engaged in sexual activity or shared needles with
original patient
Also referred to as contact tracing
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More appropriate for diseases spread through
non-sexual contact (tuberculosis, other
communicable diseases)
Purpose of Partner Notification
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Primary purpose is to prevent further
transmission of disease.
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More important with HIV/AIDS
Other goals:
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to educate and treat infected individuals
to educate, test, treat (if needed)
individuals exposed to infectious disease
Use of Partner Notification
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Partner notification is used most commonly
for syphilis and HIV/AIDS
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Contact tracing used routinely for tuberculosis
and disease outbreaks:
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Also for other STIs such as gonorrhea and
chlamydia
Measles, bacterial meningitis, Hepatitis A, severe
acute respiratory syndrome
Contact tracing systems also developed for
diseases like smallpox
Partner Notification of Sexually
Transmitted Infections
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Guided by state law
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Variations in the process depending on the
state, health department, and type of
disease
CDC recommends following steps for
effective provider referral case
management of STIs
Partner Notification of Sexually
Transmitted Infections
Pre-Interview Analysis
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Reviews medical and case data to learn:
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Establishes time patient could have spread disease
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Status of the case (new or recurrent)
Medical information on the patient
Pregnancy status for women
Issues unique to patient - embarrassment, sexual
orientation, drug use, cooperativeness, attitude, history of
domestic violence, psychiatric issues
Begins with earliest date patient could have been infected
Ends with date of treatment
May be obtained from health department, physician,
hospital, jail, prison records
Partner Notification of Sexually
Transmitted Infections
Initial Interview
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Purpose is to prevent further transmission of
disease through identification and
communication with index patient and
partner(s)
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Educating patient about seriousness of disease
and importance of cooperation
Providing patient with risk reduction plan and
appropriate community referrals (e.g., substance
abuse treatment centers, prenatal care)
Eliciting partner information from patient
Partner Notification of Sexually
Transmitted Infections
Initial Interview
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Partner elicitation accomplished by asking
patient for:
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Names (and nicknames) of sexual and needlesharing partners
Frequency and dates of exposure
Address and phone/beeper numbers
Place of employment
Physical description
Who partner lives with, where partner hangs out
Whether partner has been incarcerated
Partner Notification of Sexually
Transmitted Infections
Initial Interview
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Partner elicitation
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Can also provide information about other
high-risk individuals ( “suspects”) who are
not partners but may need medical
evaluation
Goal to obtain information to find partners
and suspects so interviewer can provide
education and risk-reduction counseling,
refer for testing and treatment
Interviewing Challenges
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Often interviewing is not straightforward
Challenging situations include:
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Finding a homeless individual who has no home
address, only information about what soup kitchen
or shelter he/she frequents
Finding a prostitute based only on “street name,”
physical description, and where usually works
Working in dangerous neighborhoods or places
(e.g., crack houses)
Partner Notification of Sexually
Transmitted Infections
Re-Interview
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Re-interview often needed to:
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Gather more partner information
Re-emphasize risk reduction and referrals
Clarify illogical statements
Elicit additional partners or suspects
Usually done within several days of
initial interview
Partner Notification of Sexually
Transmitted Infections
Case Closure
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Case is closed when investigator and
supervisor agree that all reasonable
steps to intervene in disease
transmission have been taken
Cluster Interviewing
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Cluster interviewing expedites intervention
process when there is not enough partner
information to allow investigators to reach
partners individually
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Gather information about previously unnamed
partners or cases and any persons who might
benefit from a medical examination
May identify partners whom the case patient is
unwilling to identify
Cluster Interviewing
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Cluster interview attempts to find others at risk by
interviewing patient's partners and suspects not
known to be infected
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Does not disclose names of individuals infected or at risk of
infection, conveys only that syphilis has been diagnosed in
the area
Provides each person with information about syphilis and
encourages person to get tested
Emphasizes that person can decrease risk by offering names
of partners and other high-risk individuals to be interviewed
Information may be used to determine risk profiles
and geographic locations of target groups for
screening
Cluster Interviews - Example
Tuberculosis in a Transgender Network
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Summer 1998: Baltimore City Health Department notified of 4
cases of TB among young men
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Began with traditional contact investigation
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Identified 14 contacts
Developed profile of people participating in social network:
history of membership in a “house,” attendance at specific
events, reported cross-dressing
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All part of a transgender social network, participated in “houses”
(social guilds for men who have sex with men and transgender
persons)
Process similar to cluster interviewing: people identified were not
necessarily close contacts of confirmed TB cases
Identified 91 contacts
Found 6 additional cases of TB
Partner Notification/Contact
Tracing of Tuberculosis
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Contact tracing for non-sexually transmitted
diseases similar to that for STIs
CDC and the National Tuberculosis Controllers
Association published guidelines for TB
contact tracing in 2005
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Recommend that contact investigation be
conducted when patient has confirmed or
suspected pulmonary, laryngeal, or pleural TB, and
sputum smear or chest radiograph indicates TB
Partner Notification/Contact
Tracing of Tuberculosis
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First step is to gather background
information about patient from medical
record, reporting physician, or hospital
infection control nurse
Background information used to
determine infectious period for patient
Partner Notification/Contact
Tracing of Tuberculosis
Interview
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Should occur within 1 business day of reporting for
infectious patient, within 3 business days of reporting
for non-infectious patient
Should be conducted in person
Gathers information about places where disease
transmission could have occurred: patient’s home
and congregate settings (schools, nursing homes,
correctional facilities, homeless shelters)
Asks for names, phone numbers, addresses of people
who may have been exposed
Interviewer may prioritize the places of likely
transmission, follow up with another interview
Partner Notification/Contact
Tracing of Tuberculosis
Site Visit
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Visit places of likely disease transmission to:
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Identify additional contacts, including children
Determine the likelihood of disease transmission
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Visit to homeless shelter to see how many people sleep
in same room, how much ventilation, whether people eat
together in a common area, whether shelter provides
screening or other health services)
Partner Notification/Contact
Tracing of Tuberculosis
Prioritizing Contacts
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Most important criteria:
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Secondary criteria:
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Age under 5 years
Compromised immune status, such as HIV infection
Type of exposure
Other medical conditions such as diabetes
Exposure classified by amount of air volume shared
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Smallest amount (inside a car) indicates high level of
exposure
Largest size (larger than a house) indicates lower likelihood
of exposure
Contact Tracing of
Tuberculosis - Example
TB Investigation in Ohio
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January 2005: woman came to Ashtabula County Health
Department to have tuberculin skin test
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Additional cases of TB reported to health department in March
2005
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Test was positive; subsequently developed active tuberculosis, as
indicated by chest radiograph and a positive sputum smear.
Public health nurses interviewed to obtain information about
contacts; all contacts tested negative for TB
Son of one of the patients had been experiencing symptoms
consistent with TB for previous 4 years; medical professionals had
suspected TB but none started patient on TB treatment or notified
health department
The complete contact investigation uncovered 6 cases of TB
after skin testing of 81 exposed contacts
Partner Notification in an
Outbreak
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Partner notification/contact tracing
critical during outbreak
Can identify additional cases infected
with disease and pinpoint possible sites
of disease transmission
Partner Notification in an
Outbreak
San Francisco Syphilis Outbreak
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Summer 1999: San Francisco Department of Public
Health learned of 2 cases of early-stage syphilis
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Patients did not have any information about many
partners other than Internet screen names
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Both patients met most of sexual partners in same Internet
chat room
Sent e-mails to screen names and requested reply
Partners who responded advised to undergo medical
evaluation
Identified 5 additional cases of syphilis
Responsibility for Partner
Notification
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Depending on situation and persons
involved, either a public health
professional or the patient may notify
partner(s).
Generally 3 ways to approach partner
notification:
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Health care provider
Patient
Contract referral
Responsibility for Partner
Notification
Provider Referral
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Public health professional or health care provider
notifies partners of potential disease exposure
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Notification for sexually transmitted diseases,
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Notification is confidential, with consent of infected person
Often done by disease intervention specialist (public health
professional specially trained in partner notification)
Clinicians or other public health department staff
Notification for TB contacts:
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Some health departments have team members devoted to
contact tracing
Public health nurses, other members of multidisciplinary
investigation teams
When diagnosed in hospital, infection control
practitioner or employee health nurse
Responsibility for Partner
Notification
Self/Patient Referral
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Patient takes responsibility for notifying partners of
potential exposure, referring them to medical care
Public health department staff work with patients to
help them prepare for interactions with partners
Contract Referral
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Patient agrees to notify and refer to medical care all
partners within a certain time period
If patient fails to do so, provider has permission to
notify and refer partners
Training of Investigators
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Training varies depending on background and job
description of investigator
Some receive intensive training through state health
department or CDC
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CDC has contact tracing self-study module
If responsibilities include drawing blood, should be trained in
Occupational Safety and Health Administration (OSHA)
standards and venipuncture
Role playing with practice interviews
HIV counseling and testing
Cconfidentiality
Hands-on field experience with a mentor
Training of Investigators
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Investigator must know how to:
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Must be able to apply skills with individuals who often
do not trust them, may not be particularly happy to
see them, are concerned about their confidentiality,
and may not be motivated to cooperate
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Take sexual histories
Effectively elicit partners’ names
Identify and locate contacts
Refer persons for testing, treatment, and social services
Educate and counsel persons on high risk behavior
Must gain the trust of patient and maintain confidentiality
Must be familiar with epidemiology of the disease
Legal Authority for Partner
Notification
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Legal authority for partner notification of
sexually transmitted infections resides with
states
Legal authority for mandatory disease
reporting is derived from state law; states
may have different organizational structures
and approaches depending on state laws
All 50 states require that certain diseases be
reported to state or local health department
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List of reportable diseases varies by state
Confidentiality
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Maintaining patient confidentiality is imperative
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Promotes trusting relationship between investigator and
patient
Required by law to protect the privacy of the patient
Always interview cases and partners in private
Try to notify partners face to face
Never reveal identity of original case to partner
Do not leave verbal or written messages that mention
disease
Do not give confidential information to others
Investigation documentation is confidential material
In addition to state and federal laws, each
public health department has specific
guidelines and legal regulations
Summary
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Contact tracing may be carried out for
different infectious diseases (e.g., HIV,
syphilis, TB)
May be done by provider, patient, or contract
referral
While specific procedures differ by state,
primary goal is to intervene in transmission of
infectious disease
Education, testing, treatment are additional
goals of contact tracing
References
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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, 2007.
Hogben M. Partner notification for sexually transmitted
diseases. Clinl Infect Dis. 2007;44(suppl 3):S160-S174.
Golden MR, Hogben M, Handsfield HH, St. Lawrence JS,
Potterat JJ, Holmes KK. Partner notification for HIV and STD in
the United States: Low coverage for gonorrhea, chlamydial
infection, and HIV. Sex Trans Dis. 2003;30:490-496.
Centers for Disease Control and Prevention. Smallpox response
plan and guidelines (version 3.0). Available at:
http://www.bt.cdc.gov/agent/smallpox/responseplan/index.asp. Accessed October 25, 2007.
References
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Centers for Disease Control and Prevention. Cluster of HIVinfected adolescents and young adults – Mississippi, 1999.
MMWR Morb Mortal Wkly Rep. 2000;49:861-864.
Centers for Disease Control and Prevention. Guidelines for the
investigation of contacts of persons with infectious tuberculosis.
MMWR Recomm Rep. 2005;54:1-43.
Kettunen CM, Sunmonu Y, Hodgkinson AL, et al. Contact
investigation of a case of active tuberculosis in the community.
Am J Infect Control. 2007;35:421-424.
Klausner JD, Wolf W, Fischer-Ponce L, Zolt I, Katz MH. Tracing a
syphilis outbreak through cyberspace. JAMA. 2000;284:447449.
References
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Centers for Disease Control and Prevention. Methicillin-resistant
Staphylococcus aureus infections among competitive sports
participants – Colorado, Indiana, Pennsylvania, and Los Angeles
County, 2002-2003. MMWR Morb Mort Wkly Rep. 2003;52:793-795.
Available at: http://www.cdc.gov/mmwr/preview/mmwrhtml/
mm5233a4.htm. Accessed December 15, 2006.
Centers for Disease Control and Prevention. Use of quarantine to
prevent severe acute respiratory syndrome – Taiwan, 2003. MMWR
Morb Mort Wkly Rep. 2003;52:680-683. Available at:
http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5229a2.htm.
Accessed December 15, 2006.
Centers for Disease Control and Prevention. Efficiency of quarantine
during an epidemic of severe acute respiratory syndrome – Beijing,
China, 2003. MMWR Morb Mort Wkly Rep. 2003;52:1037-1040.
Available at: http://www.cdc.gov/mmwr/preview/mmwrhtml/
mm5243a2.htm. Accessed December 15, 2006.
References
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Macke BA, Maher JE. Partner notification in the United States:
An evidence-based review. Am J Prev Med. 1999; 17:230-242.
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.
Centers for Disease Control and Prevention. Self-study modules
on tuberculosis. Module 6: Contact investigations for
tuberculosis. Available at:
http://www.cdc.gov/tb/pubs/ssmodules/module6/ss6contents.ht
m. Accessed September 26, 2007.
Teutsch SM, Churchill RE, eds. Principles and Practice of Public
Health Surveillance. New York, NY: Oxford University Press;
2000.