Contact Investigations Around Mycobacterium tuberculosis Patients Without Positive Respiratory Culture Jordan Cates, MSPH; Lisa Trieu, MPH; Douglas Proops, MD, MPH; Shama Desai Ahuja, PhD, MPH rrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr
Objective: To evaluate the yield and effectiveness of contact investigations conducted around potentially infectious tuberculosis (TB) patients with no positive respiratory culture for Mycobacterium tuberculosis in New York City (NYC). Design: All TB patients without a positive respiratory culture from 2003 to 2012 were extracted from the NYC TB registry, and all patients eligible for contact investigation and their contacts were evaluated. Patients without a positive respiratory culture were defined as eligible for contact investigation if they had a respiratory nucleic acid amplification result positive for M tuberculosis, a cavitary chest radiograph, or a positive respiratory acid-fast bacilli smear. Setting: NYC, New York. Main Outcome Measures: To evaluate the yield of the investigations, the number of contacts identified and the outcome of testing was quantified. Potential transmission was defined on the basis of whether active TB patients were detected among the contacts and if a contact had a TB test conversion. Results: From 2003 to 2012, there were 2191 TB patients without a positive respiratory culture in NYC, 374 (17%) of which were considered eligible for contact investigation. A total of 11 096 contacts were identified around 300 (80%) eligible patients, 136 of whom had a diagnosis of TB infection; of those with TB infection who initiated preventive treatment, 66% completed treatment. Potential transmission was identified around 14 patients, with the identification of 2 additional cases of active TB and 15 contacts with TB infection test conversion. Conclusions: Conducting contact investigations around patients without a positive respiratory culture yielded evidence of possible transmission and led to the identification and treatment of new TB cases and those with TB infection. These findings suggest J Public Health Management Practice, 2016, 22(3), 275–282 C 2016 Wolters Kluwer Health, Inc. All rights reserved. Copyright
that these investigations should be conducted in settings where resources permit. KEY WORDS: contact tracing, New York City, respiratory culture
Tuberculosis (TB) is a widespread infectious disease that contributes largely to global public health burden. Contact investigations provide an effective and crucial strategy for controlling TB. The goals of contact investigations are to identify and treat additional cases of active TB disease and TB infection in order to avert future patients and break the chain of disease transmission. Because of limited resources and high incidence of TB in some countries, contact investigations are not always feasible even around the most infectious patients. In the United States, a low TB burden nation with a rate of 3.2 cases per 100 000 population in 2013,1 contact investigations have proven to be an effective activity for TB control.1-3 In New York City (NYC), which contributes the largest burden of tuberculosis of any US city, contact investigations are considered an integral part of TB control practices.4 NYC experienced an 83% reduction in TB cases since the peak of Author Affiliations: Department of Epidemiology, The University of North Carolina at Chapel Hill (Ms Cates); and Bureau of Tuberculosis Control, New York City Department of Health and Mental Hygiene, New York (Ms Trieu and Drs Proops and Desai Ahuja). The authors thank the New York City Department of Health and Mental Hygiene (NYC DOHMH), Bureau of Tuberculosis Control, field and clinic staff for their efforts in contact investigation and case management. They also thank the NYC DOHMH EpiScholars program. There are no conflicts of interest among any of the authors. All authors substantially contributed to the drafting, editing, or review of the manuscript. Correspondence: Lisa Trieu, MPH, Bureau of Tuberculosis Control, New York City Department of Health and Mental Hygiene, 42-09 28th St, 21st Floor, CN72B, WS 21-08, Long Island City, NY 11101 ([email protected]). DOI: 10.1097/PHH.0000000000000261
275 Copyright © 2016 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
276 ❘ Journal of Public Health Management and Practice its TB epidemic in 1992, which can be partly attributed to rigorous contact investigations. Contact investigations, although effective, are labor-intensive and costly. In an era of declining resources, it is important to prioritize contact investigations, particularly for patients most likely to be infectious. The potential infectiousness of a patient is associated with several clinical characteristics and laboratory diagnostics, including culture, microscopy, and chest radiographic (CXR) results. Research and practice show that TB patients with positive cultures from respiratory sites are more likely to be infectious.5-7 Among patients with a positive culture, infectiousness is even greater when acid-fast bacilli (AFB) are detected on respiratory smear microscopy8-10 and among patients with evidence of cavities on CXR.11 To date, there is no empirical evidence to indicate the level of infectiousness of patients who present with AFB respiratory smearpositive disease or with cavities on CXR but do not have a positive respiratory culture. According to NYC Department of Health and Mental Hygiene (DOHMH) guidelines, in the absence of a positive respiratory culture, contact investigations are recommended if the patient has a positive respiratory smear, a positive respiratory nucleic acid amplification (NAA) test result, or cavities on CXR.2 The Centers for Disease Control and Prevention recommendations for initiating a contact investigation are similar, except they do not recommend initiating an investigation when the patient has a positive smear but negative NAA result.5 Given the resource-intensiveness of contact investigations, it is important to assess the potential infectiousness of patients without positive respiratory cultures and whether conducting an investigation around these patients contributes toward achieving the goal of eliminating TB as a public health problem. We present an analysis of contact investigations surrounding patients without a positive respiratory culture in NYC from January 1, 2003, to December 31, 2012. Specifically, we aim to (1) compare patients eligible for contact investigation with those not eligible; (2) evaluate the yield of these investigations with respect to identification of additional patients of active TB and contacts with TB infection; (3) gauge the effectiveness of these investigations based on initiation of treatment of infected contacts; and (4) assess the likelihood of transmission surrounding these investigations.
● Methods Study design and population The study population consisted of all patients with pulmonary disease without a positive respiratory culture who were verified as a TB case in NYC from January 1,
2003, to December 31, 2012, and their respective contacts. It was possible for a patient to not have a positive respiratory culture for Mycobacterium tuberculosis complex (Mtb) either because no growth was detected or because no respiratory specimen was collected. It was also possible for the study population to include patients with a positive culture from a nonrespiratory site, as long as no positive respiratory culture existed. We included only household and leisure contacts in the analysis to focus on those with the most intense exposure and greatest likelihood of infection. The eligibility criteria for a contact investigation were incorporated from the NYC DOHMH Bureau of Tuberculosis Control’s (BTBC’s) protocols.2 A patient without a positive respiratory culture was considered eligible for a contact investigation if any of the following were present: a respiratory NAA result positive for Mtb, a cavitary CXR, or a positive respiratory AFB smear. Source case investigations surrounding patients younger than 5 years were not included, unless these children separately met the eligibility criteria for a contact investigation.
Study definitions All contacts with a history of TB infection (“prior positive”) were considered ineligible for TB testing during the contact investigation. A prior positive contact was defined as (1) a contact who had a positive TB test result that was documented before the infectious period began for the index patient, or (2) a contact who had a history of TB disease. Prior positive contacts were excluded to more easily characterize newly identified infection. The infectious period of the index patient was defined as the 12-week period prior to the start of treatment of active TB.2 Contacts were tested for TB infection with either the tuberculin skin test (TST) or a blood-based interferon-γ release assay QuantiFERONGold (QFT) test. Contacts who were eligible for testing were considered to have completed testing if they had a positive test from the start of the index patient’s infectious period until 9 months after the date of last exposure (to allot time for completion of a contact investigation) or a negative test after the end of the window period. The window period is the 8-week period after exposure during which the immune system may not have yet developed a response to TB infection.2 If the date the TB patient initiated treatment was missing in the data set, either the date of death, if applicable, or the date of first reporting to the BTBC was substituted for calculation of the infectious period and window period. The BTBC’s surveillance registry was used to verify whether or not any contact later broke down with TB disease.
Copyright © 2016 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
Contact Tracing Around Non–Culture-Positive TB Patients
❘ 277
FIGURE 1 ● Number of TB Patients, Patients Without a Positive Culture for
Mycobacterium tuberculosis, and Non–Culture-Positive Patients Eligible for Contact Investigation, New York City, 2003-2012 qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq
Abbreviation: TB, tuberculosis.
We defined likely transmission around patients based on 2 criteria. The first indicator of transmission was if any contact was identified as a secondary case of TB disease within 9 months of initial case report. A second indicator was if any contact had a documented conversion of a TB test result from negative to positive within 2 years; however, both tests must have been of the same test type, and for TST, there must have been an increase in induration of at least 10 mm.
Data analysis To evaluate the yield of contact investigations around patients without a positive respiratory culture, we quantified numbers and proportions of contacts by their TB test outcomes. Trends of patients without a positive respiratory culture over time were evaluated using the Cochran-Armitage test for trend. Categorical variables were analyzed using Pearson χ 2 tests with an a priori significant P value level of .05 comparing patients eligible for contact investigation with those not eligible. All analyses were performed using SAS 9.2 (Cary, North Carolina). All data were obtained from the NYC DOHMH BTBC electronic surveillance and patient management system (Maven; Consilience Software, Austin, Texas). This study was considered to be a program evaluation by the NYC DOHMH using data already collected for programmatic purposes.
● Results From 2003 to 2012, there were 8692 cases of TB in NYC, of which there were 2191 (25%) patients without a positive respiratory culture. Of these 2191 patients, 59 (3%) had a positive Mtb culture result from a nonrespiratory
site but negative respiratory cultures, 155 (7%) did not have a respiratory culture performed, and the remaining 1977 patients had negative respiratory cultures. Of the 2191 patients without a positive respiratory culture, 374 (18%) were eligible for contact investigation. The median number of patients eligible each year over the study period was 35 (interquartile range: 31-38), with the distribution of eligible patients each year depicted in Figure 1. There was a decline in the total number of TB patients in NYC over the study period but a slight increase in the percentage of TB patients without a positive respiratory culture out of total patients (Ptrend = .04; Figure 1). However, there was not a significant change in the percentage of patients without a positive respiratory culture eligible for a contact investigation over the study period (Ptrend = .67). Two hundred fifty-two (67%) patients were eligible for contact investigation based solely on having a positive AFB smear result (Table 1). Compared with patients without a positive respiratory culture TABLE 1 ● Tuberculosis Patients Eligible for Contact Investigation in New York City From January 1, 2003, to December 31, 2012, by Eligibility Criteria (N = 374) qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq
Eligibility Criteriaa Cavities on chest radiograph NAA positive AFB smear positive AFB smear positive and cavities on chest radiograph AFB smear positive and NAA positive
n
%
69 16 252 18
18 4 67 5
19
5
Abbreviations: AFB, acid-fast bacilli; NAA, nucleic acid amplification; TB, tuberculosis. a Eligibility criteria for contact investigation are based on the New York City Department of Health and Mental Hygiene protocol for contact investigations. Patients were considered eligible for a contact investigation if they had pulmonary TB or both pulmonary and extrapulmonary TB, and if they had cavities on chest radiograph, positive respiratory NAA results, or positive respiratory smear results.
Copyright © 2016 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
278 ❘ Journal of Public Health Management and Practice not eligible for contact investigation, patients who were eligible for investigation were more likely to be US-born (P < .01), older (P < .01), living in the United States longer if foreign-born (P < .01), and a greater proportion were white, non-Hispanic (P < .01) (Table 2).
Of the 374 patients eligible for a contact investigation, 300 (80%) had at least 1 contact identified. Around these 300 patients, 1096 contacts were identified (Figure 2) with a median of 3 contacts identified per patient (interquartile range: 2-5). Of the 1096 contacts, 107 (9%) were ineligible for testing; 106 had a prior
TABLE 2 ● Characteristics of All TB Patients Without a Positive Respiratory Culture (N = 2191) and Those Eligible and
Not Eligible for Contact Investigations in New York City From January 1, 2003, to December 31, 2012 qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq Eligible for Contact Investigationa
Total Patients Patient Characteristic Total Sex Female Male Age, y ≤4 5-19 20-44 45-64 ≥65 Birth in the United States No Yes Time in the United States,c y 5 Race and ethnicity White, non-Hispanic Black, non-Hispanic Hispanic Asian/Pacific Islander Otherd HIV status Positive Negative Unknowne Site of disease Pulmonary Extrapulmonary Both Respiratory smear positivef NAA positive Initial cavitary chest radiographf
Not Eligible for Contact Investigationa
n
%
n
%
n
%
Pb
2191
100
374
17
1817
83
...
982 1209
45 55
167 207
45 55
815 1002
45 55
.90
102 219 938 659 273
5 10 43 30 12
4 21 115 138 96
1 6 31 37 26
98 198 823 521 177
5 11 45 29 10
Objective: To evaluate the yield and effectiveness of contact investigations conducted around potentially infectious tuberculosis (TB) patients with no positive respiratory culture for Mycobacterium tuberculosis in New York City (NYC). Design: All TB patients without a positive respiratory culture from 2003 to 2012 were extracted from the NYC TB registry, and all patients eligible for contact investigation and their contacts were evaluated. Patients without a positive respiratory culture were defined as eligible for contact investigation if they had a respiratory nucleic acid amplification result positive for M tuberculosis, a cavitary chest radiograph, or a positive respiratory acid-fast bacilli smear. Setting: NYC, New York. Main Outcome Measures: To evaluate the yield of the investigations, the number of contacts identified and the outcome of testing was quantified. Potential transmission was defined on the basis of whether active TB patients were detected among the contacts and if a contact had a TB test conversion. Results: From 2003 to 2012, there were 2191 TB patients without a positive respiratory culture in NYC, 374 (17%) of which were considered eligible for contact investigation. A total of 11 096 contacts were identified around 300 (80%) eligible patients, 136 of whom had a diagnosis of TB infection; of those with TB infection who initiated preventive treatment, 66% completed treatment. Potential transmission was identified around 14 patients, with the identification of 2 additional cases of active TB and 15 contacts with TB infection test conversion. Conclusions: Conducting contact investigations around patients without a positive respiratory culture yielded evidence of possible transmission and led to the identification and treatment of new TB cases and those with TB infection. These findings suggest J Public Health Management Practice, 2016, 22(3), 275–282 C 2016 Wolters Kluwer Health, Inc. All rights reserved. Copyright
that these investigations should be conducted in settings where resources permit. KEY WORDS: contact tracing, New York City, respiratory culture
Tuberculosis (TB) is a widespread infectious disease that contributes largely to global public health burden. Contact investigations provide an effective and crucial strategy for controlling TB. The goals of contact investigations are to identify and treat additional cases of active TB disease and TB infection in order to avert future patients and break the chain of disease transmission. Because of limited resources and high incidence of TB in some countries, contact investigations are not always feasible even around the most infectious patients. In the United States, a low TB burden nation with a rate of 3.2 cases per 100 000 population in 2013,1 contact investigations have proven to be an effective activity for TB control.1-3 In New York City (NYC), which contributes the largest burden of tuberculosis of any US city, contact investigations are considered an integral part of TB control practices.4 NYC experienced an 83% reduction in TB cases since the peak of Author Affiliations: Department of Epidemiology, The University of North Carolina at Chapel Hill (Ms Cates); and Bureau of Tuberculosis Control, New York City Department of Health and Mental Hygiene, New York (Ms Trieu and Drs Proops and Desai Ahuja). The authors thank the New York City Department of Health and Mental Hygiene (NYC DOHMH), Bureau of Tuberculosis Control, field and clinic staff for their efforts in contact investigation and case management. They also thank the NYC DOHMH EpiScholars program. There are no conflicts of interest among any of the authors. All authors substantially contributed to the drafting, editing, or review of the manuscript. Correspondence: Lisa Trieu, MPH, Bureau of Tuberculosis Control, New York City Department of Health and Mental Hygiene, 42-09 28th St, 21st Floor, CN72B, WS 21-08, Long Island City, NY 11101 ([email protected]). DOI: 10.1097/PHH.0000000000000261
275 Copyright © 2016 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
276 ❘ Journal of Public Health Management and Practice its TB epidemic in 1992, which can be partly attributed to rigorous contact investigations. Contact investigations, although effective, are labor-intensive and costly. In an era of declining resources, it is important to prioritize contact investigations, particularly for patients most likely to be infectious. The potential infectiousness of a patient is associated with several clinical characteristics and laboratory diagnostics, including culture, microscopy, and chest radiographic (CXR) results. Research and practice show that TB patients with positive cultures from respiratory sites are more likely to be infectious.5-7 Among patients with a positive culture, infectiousness is even greater when acid-fast bacilli (AFB) are detected on respiratory smear microscopy8-10 and among patients with evidence of cavities on CXR.11 To date, there is no empirical evidence to indicate the level of infectiousness of patients who present with AFB respiratory smearpositive disease or with cavities on CXR but do not have a positive respiratory culture. According to NYC Department of Health and Mental Hygiene (DOHMH) guidelines, in the absence of a positive respiratory culture, contact investigations are recommended if the patient has a positive respiratory smear, a positive respiratory nucleic acid amplification (NAA) test result, or cavities on CXR.2 The Centers for Disease Control and Prevention recommendations for initiating a contact investigation are similar, except they do not recommend initiating an investigation when the patient has a positive smear but negative NAA result.5 Given the resource-intensiveness of contact investigations, it is important to assess the potential infectiousness of patients without positive respiratory cultures and whether conducting an investigation around these patients contributes toward achieving the goal of eliminating TB as a public health problem. We present an analysis of contact investigations surrounding patients without a positive respiratory culture in NYC from January 1, 2003, to December 31, 2012. Specifically, we aim to (1) compare patients eligible for contact investigation with those not eligible; (2) evaluate the yield of these investigations with respect to identification of additional patients of active TB and contacts with TB infection; (3) gauge the effectiveness of these investigations based on initiation of treatment of infected contacts; and (4) assess the likelihood of transmission surrounding these investigations.
● Methods Study design and population The study population consisted of all patients with pulmonary disease without a positive respiratory culture who were verified as a TB case in NYC from January 1,
2003, to December 31, 2012, and their respective contacts. It was possible for a patient to not have a positive respiratory culture for Mycobacterium tuberculosis complex (Mtb) either because no growth was detected or because no respiratory specimen was collected. It was also possible for the study population to include patients with a positive culture from a nonrespiratory site, as long as no positive respiratory culture existed. We included only household and leisure contacts in the analysis to focus on those with the most intense exposure and greatest likelihood of infection. The eligibility criteria for a contact investigation were incorporated from the NYC DOHMH Bureau of Tuberculosis Control’s (BTBC’s) protocols.2 A patient without a positive respiratory culture was considered eligible for a contact investigation if any of the following were present: a respiratory NAA result positive for Mtb, a cavitary CXR, or a positive respiratory AFB smear. Source case investigations surrounding patients younger than 5 years were not included, unless these children separately met the eligibility criteria for a contact investigation.
Study definitions All contacts with a history of TB infection (“prior positive”) were considered ineligible for TB testing during the contact investigation. A prior positive contact was defined as (1) a contact who had a positive TB test result that was documented before the infectious period began for the index patient, or (2) a contact who had a history of TB disease. Prior positive contacts were excluded to more easily characterize newly identified infection. The infectious period of the index patient was defined as the 12-week period prior to the start of treatment of active TB.2 Contacts were tested for TB infection with either the tuberculin skin test (TST) or a blood-based interferon-γ release assay QuantiFERONGold (QFT) test. Contacts who were eligible for testing were considered to have completed testing if they had a positive test from the start of the index patient’s infectious period until 9 months after the date of last exposure (to allot time for completion of a contact investigation) or a negative test after the end of the window period. The window period is the 8-week period after exposure during which the immune system may not have yet developed a response to TB infection.2 If the date the TB patient initiated treatment was missing in the data set, either the date of death, if applicable, or the date of first reporting to the BTBC was substituted for calculation of the infectious period and window period. The BTBC’s surveillance registry was used to verify whether or not any contact later broke down with TB disease.
Copyright © 2016 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
Contact Tracing Around Non–Culture-Positive TB Patients
❘ 277
FIGURE 1 ● Number of TB Patients, Patients Without a Positive Culture for
Mycobacterium tuberculosis, and Non–Culture-Positive Patients Eligible for Contact Investigation, New York City, 2003-2012 qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq
Abbreviation: TB, tuberculosis.
We defined likely transmission around patients based on 2 criteria. The first indicator of transmission was if any contact was identified as a secondary case of TB disease within 9 months of initial case report. A second indicator was if any contact had a documented conversion of a TB test result from negative to positive within 2 years; however, both tests must have been of the same test type, and for TST, there must have been an increase in induration of at least 10 mm.
Data analysis To evaluate the yield of contact investigations around patients without a positive respiratory culture, we quantified numbers and proportions of contacts by their TB test outcomes. Trends of patients without a positive respiratory culture over time were evaluated using the Cochran-Armitage test for trend. Categorical variables were analyzed using Pearson χ 2 tests with an a priori significant P value level of .05 comparing patients eligible for contact investigation with those not eligible. All analyses were performed using SAS 9.2 (Cary, North Carolina). All data were obtained from the NYC DOHMH BTBC electronic surveillance and patient management system (Maven; Consilience Software, Austin, Texas). This study was considered to be a program evaluation by the NYC DOHMH using data already collected for programmatic purposes.
● Results From 2003 to 2012, there were 8692 cases of TB in NYC, of which there were 2191 (25%) patients without a positive respiratory culture. Of these 2191 patients, 59 (3%) had a positive Mtb culture result from a nonrespiratory
site but negative respiratory cultures, 155 (7%) did not have a respiratory culture performed, and the remaining 1977 patients had negative respiratory cultures. Of the 2191 patients without a positive respiratory culture, 374 (18%) were eligible for contact investigation. The median number of patients eligible each year over the study period was 35 (interquartile range: 31-38), with the distribution of eligible patients each year depicted in Figure 1. There was a decline in the total number of TB patients in NYC over the study period but a slight increase in the percentage of TB patients without a positive respiratory culture out of total patients (Ptrend = .04; Figure 1). However, there was not a significant change in the percentage of patients without a positive respiratory culture eligible for a contact investigation over the study period (Ptrend = .67). Two hundred fifty-two (67%) patients were eligible for contact investigation based solely on having a positive AFB smear result (Table 1). Compared with patients without a positive respiratory culture TABLE 1 ● Tuberculosis Patients Eligible for Contact Investigation in New York City From January 1, 2003, to December 31, 2012, by Eligibility Criteria (N = 374) qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq
Eligibility Criteriaa Cavities on chest radiograph NAA positive AFB smear positive AFB smear positive and cavities on chest radiograph AFB smear positive and NAA positive
n
%
69 16 252 18
18 4 67 5
19
5
Abbreviations: AFB, acid-fast bacilli; NAA, nucleic acid amplification; TB, tuberculosis. a Eligibility criteria for contact investigation are based on the New York City Department of Health and Mental Hygiene protocol for contact investigations. Patients were considered eligible for a contact investigation if they had pulmonary TB or both pulmonary and extrapulmonary TB, and if they had cavities on chest radiograph, positive respiratory NAA results, or positive respiratory smear results.
Copyright © 2016 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
278 ❘ Journal of Public Health Management and Practice not eligible for contact investigation, patients who were eligible for investigation were more likely to be US-born (P < .01), older (P < .01), living in the United States longer if foreign-born (P < .01), and a greater proportion were white, non-Hispanic (P < .01) (Table 2).
Of the 374 patients eligible for a contact investigation, 300 (80%) had at least 1 contact identified. Around these 300 patients, 1096 contacts were identified (Figure 2) with a median of 3 contacts identified per patient (interquartile range: 2-5). Of the 1096 contacts, 107 (9%) were ineligible for testing; 106 had a prior
TABLE 2 ● Characteristics of All TB Patients Without a Positive Respiratory Culture (N = 2191) and Those Eligible and
Not Eligible for Contact Investigations in New York City From January 1, 2003, to December 31, 2012 qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq Eligible for Contact Investigationa
Total Patients Patient Characteristic Total Sex Female Male Age, y ≤4 5-19 20-44 45-64 ≥65 Birth in the United States No Yes Time in the United States,c y 5 Race and ethnicity White, non-Hispanic Black, non-Hispanic Hispanic Asian/Pacific Islander Otherd HIV status Positive Negative Unknowne Site of disease Pulmonary Extrapulmonary Both Respiratory smear positivef NAA positive Initial cavitary chest radiographf
Not Eligible for Contact Investigationa
n
%
n
%
n
%
Pb
2191
100
374
17
1817
83
...
982 1209
45 55
167 207
45 55
815 1002
45 55
.90
102 219 938 659 273
5 10 43 30 12
4 21 115 138 96
1 6 31 37 26
98 198 823 521 177
5 11 45 29 10
