INFECTIOUS DISEASE SURVEILLANCE
in Canadian Federal Penitentiaries 2005-2006

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Part I: Introduction and Methods

Chapter 1: Public Health in Corrections

Background

This report follows previous reports on infectious disease in Correctional Service Canada (CSC) for 1998-2004 (CSC 2001; CSC 2003; CSC 2005; CSC 2008) and includes surveillance data for inmates on human immunodeficiency virus (HIV), hepatitis A (HAV), hepatitis B (HBV), hepatitis C (HCV), sexually transmitted infections (STI), and tuberculosis (TB) (TB data are reported for both inmates and staff). This report summarizes the analysis of surveillance data for January 1 2005 to December 31 2006.

The Correctional Service of Canada (CSC) is responsible for the administration of correctional sentences of two years or more and for the preparation of offenders for their successful return and reintegration into the community. In 2005-2006, CSC operated 58 correctional institutions, which include minimum-, medium-, maximum- and multi-level security facilities in five regions (Figure 1.1). Federally sentenced women offenders are housed in female-specific institutions (Nova Institution for Women in Atlantic Region; Joliette Institution in Quebec Region; Grand Valley Institution for Women in Ontario Region; Edmonton Institution for Women and Okimaw Ochi Healing Lodge in Prairies Region, and Fraser Valley Institution for Women in Pacific Region) (see Appendix G, Table G.1).

 

Figure 1.1: Administrative Regions in Correctional Service Canada

 

CSC is mandated by the Corrections and Conditional Release Act (CCRA) to provide essential health services for persons convicted of federal offences, as well as reasonable access to non-essential mental health care services. Voluntary testing for HIV, hepatitis B and C, STI¹ and TB, is offered to all inmates on admission. Inmates are considered ‘new admissions’ for 6-12 weeks after sentencing, while they complete their orientations and correctional program planning. Reception units also administer the ‘Reception Awareness Program (RAP), which focuses on infectious disease awareness and prevention and health services available to inmates in CSC. Upon completing the orientation program, the inmate is placed in the institution that will be his/her home for the duration of the sentence (inmates may transfer between institutions). Testing is available upon request by an inmate at any time throughout his/her sentence, by recommendation of the facility physician or nurse, as part of contact tracing, upon clinical indication of infection, or after involvement in an incident where exposure to an infectious agent may have occurred. Inmates are offered annual tuberculosis screening. Harm-reduction initiatives include the availability of condoms, dental dams, water-based lubricants and bleach at several locations in all institutions. Routine immunization for hepatitis A and hepatitis B is offered following serological testing protocols and annual vaccination against influenza is also offered.

In accordance with Commissioner’s Directive (CD) 800 Health Services, inmates are required to be seen by a nurse within 24 hours of admission² and are given a thorough health assessment within 14 days (CSC 2009a). Further, as prescribed in CD 821 Infectious Diseases, it is the policy of CSC to engage all newly admitted inmates in risk screening and to offer testing for bloodborne and sexually transmitted infections (CSC 2009b).

Aggregate Infectious Diseases Surveillance System (IDSS)

Each institution provides aggregate monthly information on the number of tests, test results, transfers, and releases to the community for HIV and HCV. Diagnosis cases of acuteHAV, HBV and STI are also recorded. Data are also collected for the numbers of initial and ongoing assessments performed, as well as for recording the number of active TB cases. Information collected by the CSC-IDSS originate at the Health Care Unit of each federal correctional facility and are submitted to the Regional Infectious Disease Coordinator. Validation of the data is done at the regional level. Regional data are submitted to the epidemiologist, CSC National Infectious Disease Program at National Headquarters (NHQ). Further data validation and accuracy checks are conducted. Data are then compiled to a national level.

Enhanced Web-enabled Infectious Disease
Surveillance System (Web-IDSS)

On admission, inmates are offered screening for tuberculosis. This includes a baseline two-step tuberculin-skin test (TST), a symptom and risk factors checklist, and a TB history (i.e., previous active TB, previous TST results, BCG history). All inmates are also offered ongoing assessment throughout their incarceration history (see glossary for details). Duplicate forms are submitted to NHQ and entered into a normalized electronic database (Web-IDSS). Staff assessments are conducted by nurses from the Public Health and Occupational Safely Program (PHOSP), Health Canada (HC). Hard copy duplicate forms are submitted directly to the Tuberculosis Prevention and Control Program (TBPC), Public Health Agency of Canada (PHAC) and are entered into the same normalized electronic database. The data flow of tuberculosis assessments has been described in more detail elsewhere (CSC, 2005). Screening forms for bloodborne and sexually transmitted infections were introduced early in 2005, so the data presented in this report (see Surveillance Data Analysis below for more details) do not represent a full calendar year for 2005 and must be interpreted with caution. As with TB forms, duplicate forms are submitted to NHQ for data entry. Data are stripped of identifiers and exported for analysis.

Immunization Data

Data on the number of immunizations for HAV and HBV in fiscal 2004-2005 were obtained from a review of administrative financial purchase order records, since all vaccines are ordered by the regions from a National Master Standing Order (NMSO) and paid for by National Headquarters, National Infectious Disease Program. A limitation of these data include regions obtaining vaccine from provincial public health or purchasing vaccine directly.

Surveillance Data Analysis

IDSS Aggregate Data

This report is organized into chapters by disease (or pathogen). Detailed regional data for 2005 – 2006 are presented in the corresponding Appendices, while the main text includes cumulative national data to 2006 and a general discussion of trends. For HIV and HCV, IDSS data include the number of tests and corresponding results by inmate status. Test positivity rates were calculated by using the number of positive disease test reports as the numerator and the number of inmates who completed testing for the disease as the denominator. Data were also pooled and overall results calculated. Data were analyzed across CSC regions and combined for overall national results.

Web-IDSS Line-listed Data

Bloodborne and Sexually Transmitted Infections

This report is the first to include data from the enhanced surveillance system for bloodborne and sexually transmitted infections (BBSTI). As the staggered implementation of the enhanced screening forms took place early in 2005, the data for this year are incomplete and should be interpreted with caution. Data from duplicate hardcopy forms are submitted to NHQ and entered into Web-IDSS. A delimited text file without identifiers was exported from Web-IDSS and imported to SAS for analysis.

In this report, prevalence estimates for BBSTI (HIV, HCV, STI) will be compared to the IDSS data to examine external validity and consistency. Once assurance of the program and data integrity is obtained, the enhanced surveillance program will replace the aggregate reporting system to avoid duplication of work. The enhanced surveillance data allow an examination of data such as previous testing (and outcome), risk factors on admission and association with prevalent infection. In addition to HIV and HCV, the enhanced surveillance data allow more precise estimates of HAV and HBV susceptibility on admission, diagnosis of active cases, and carrier status (for HBV). For those who test negative on admission, an estimate of seroconversion rates can be calculated.

Tuberculosis Analysis

Tuberculosis assessment data included in the analysis and presented in this report were exported from Web-IDSS. A delimited text file without identifiers was exported from Web-IDSS and imported to SAS for analysis.

The interpretation of the TST is dependent upon the time from tuberculin injection to reading. The following outcome categories are possible for each assessment:

First TST of two-step and annual follow-up TST:

i) Positive;

ii) Negative;

iii) A ‘read no-show’, where tuberculin is administered but the induration is not read;

iv) An ‘invalid’ TST, where the induration is read as negative BUT the time to read is outside the prescribed guidelines of 48-72 hours (a “false negative”).

The second TST of a two-step TST, in addition to the above, could also be:

v) An incomplete two-step TST, where a second TST is not performed to complete the baseline measurement where warranted based on a negative first step;

vi) An invalid two-step TST, where the second step of the two-step is not administered within the prescribed time frame of 7-365 days³ of the first administration of tuberculin.

In addition, several instances result in no TST data:

vii) A refusal;

viii) A medical contraindication to TST testing, such as an allergy;

ix) A blank or unknown result.

These outcome categories are coded for in the analysis in a hierarchical fashion, since the categories are mutually exclusive. A TST invalidated in both the first and second steps of the two-step TST is categorized according to the first of the two tests.

Sub-Population Analysis

In 2007 CSC Health Services identified several priorities for the next five years. Included in these priorities are increasing health information and recognizing that specific strategies are required to address the health needs of inmates of Aboriginal identity and federally sentenced females (women offenders). Using self-reported data on country of birth and Aboriginal identity, inmates are classified into three groups according to “origin”: Canadian-born non-Aboriginal, Canadian-born Aboriginal, and Foreign-born. To this end surveillance data are stratified where possible by origin and gender. In addition, data are presented in the appendices by region and are discussed in the body of this document.

The IDSS data have been in use since 2000 and represent the “best” estimate for prevalence. In addition, they provide consistency for historical comparisons against previous reported data. Therefore the aggregate IDSS data will continue to provide the “best” estimates for measures that build on previous reports (i.e., prevalence estimates).

This report is the first to include the enhanced Web-IDSS data. These data will be used to supplement the report with information not available in the aggregate IDSS (i.e., with information on previous testing history). A comparison is made of the enhanced data to assess limitations or gaps. Efforts have been made in the intervening time frame from the end the reporting period to publication to address these limitations.

Data Updates

As data are received, entered, updated, validated, or as new records are added to the Web-IDSS database, the analysis from years previously reported are updated accordingly. Ongoing data quality assessments are also conducted. This report contains results from the most up-to-date tuberculosis data to June 2010 and BBSTI data to September 2010.

Populations

The total annual incarcerated populations under health surveillance for 2005 – 2006 are shown in Table 1.1. The number of new admissions rose 5% from 2005 (4,819) to 2006 (5,079). An overall rise in population from 2005 – 2006 was accompanied by a corresponding increase in both male and female populations. New admissions are defined for the purpose of this report as new warrants of committal issued in the calendar year, as reported by the CSC Offender Management System.

Where indicated, evaluation of disease prevalence is done separately for new admissions and for general population inmates. In order to maintain comparability across years, the point-prevalence calculation using year-end figures is continued. However, in calculating a period-prevalence for a calendar year, the population of new admissions was added to the population that started the year in order to maintain the total number of persons at risk in the year.

 

Table 1.1: Federal Incarcerated Populations under Surveillance, CSC, 2005-2006

	2005†			2006‡
	Males	Females	Total	Males	Females	Total
† - source: Performance Assurance, CSC, as of April 6th, 2006 ‡ - source: Performance Assurance, CSC, as of July 15th, 2007
Atlantic	1,662	82	1,744	1,765	99	1,864
New Admissions	534	42	576	533	39	572
General Population	1,128	40	1,168	1,232	60	1,292
Quebec	3,990	105	4,095	4,128	121	4,249
New Admissions	1,027	35	1,062	927	39	966
General Population	2,963	70	3,033	3,201	82	3,283
Ontario	4,439	178	4,617	4,787	194	4,981
New Admissions	1,248	74	1,322	1,299	90	1,389
General Population	3,191	104	3,295	3,488	104	3,592
Prairie	4,026	225	4,251	4,462	241	4,703
New Admissions	1,252	99	1,351	1,469	95	1,564
General Population	2,774	126	2,900	2,993	146	3,139
Pacific	2,267	67	2,334	2,469	93	2,562
New Admissions	488	20	508	548	40	588
General Population	1,779	47	1,826	1,921	53	1,974
Canada	16,384	657	17,041	17,611	748	18,359
New Admissions	4,549	270	4,819	4,776	303	5,079
General Population	11,835	387	12,222	12,835	445	13,280

 

Enhanced Surveillance of Infectious Diseases

Enhanced screening forms were introduced in February 2005, following a pilot conducted in 2004. Therefore 2005 is not a complete calendar year of observation; in addition, uptake of the forms was staggered as institutions received stock of duplicate forms and were brought up to speed by regional and national public health staff. By 2006, utilization of the forms for enhanced screening was for the most part well established in all institutions. For this reason, analysis of the Web-IDSS data, with a few exceptions, is conducted on the data for 2005 and 2006 combined.

Table 1.2.i shows the combined number of new admissions⁴ to CSC in 2005 and 2006, stratified by gender and Aboriginal identity for each region. Six percent (6%) of all new admissions were female and 94% were male. Eighteen percent (18%) of admissions were of Aboriginal origin. Among female new admissions, 31% were Aboriginal while among male admissions 18% were Aboriginal. Prairies Region (28%) and Ontario Region (27%) had the highest  proportion of new admissions.

Table 1.2.ii shows the combined number of new admissions for 2005 and 2006 for whom enhanced BBSTI screening participation was recorded in Web-IDSS. In Table 1.2.ii the percentages shown indicate the proportion of new admissions in that category participating in enhanced BBSTI screening. For example, in Ontario 83% of all new admissions are recorded in Web-IDSS. Of note is that among female new admissions, 70% of Aboriginals and 48% of non-Aboriginals were recorded, while among males, 54% of Aboriginals and 61% of non-Aboriginals were recorded in Web-IDSS. Overall, 59% of all new admissions were recorded in Web-IDSS as participating in enhanced BBSTI screening.

 

Table 1.2.i: Combined New Admissions^† 2005-2006 by Region, Gender, and Aboriginal Identity

	Females			Males			Total
	Aboriginal	Non-Aboriginal	Total	Aboriginal	Non-Aboriginal	Total
† - New warrants of committal Source: Performance Assurance, CSC, as of August, 2008
Atlantic	11	70	81	80	987	1,067	1,148	12%
Quebec	5	69	74	104	1,842	1,946	2,020	22%
Ontario	21	142	163	219	2,313	2,532	2,695	27%
Pairies	107	86	193	1,070	1,642	2,712	2,905	28%
Pacific	19	38	57	191	839	1,030	1,087	11%
Totals	163	405	568	1,664	7,623	9,287	9,855
	Females			Males			Total
Aboriginal	163	31%		1,664	18%		1,827	18%
Non-Aboriginal	405	69%		7,623	82%		8,028	82%
Totals	568	6%		9,287	94%		9,855	100%

Table 1.2.ii: Combined New Admissions^† 2005-2006 by Region, Gender, and Aboriginal Identity:
Participation in Enhanced Screening^‡

	Females			Males			TOTAL1
	Aboriginal	Non-Aboriginal	Total	Aboriginal	Non-Aboriginal	Total
† - Inmate status reported as "New Admission" by nurse at assessment ‡ - Percent refers to proportion of total number of new admissions in a category in Web-IDSS data when compared to the total number in Table 1.2.i. 1 – includes 16 gender unknown Source: Web-IDSS Enhanced Surveillance Data, CSC 2010
Atlantic	5	46	51	28	382	410	463	40%
Quebec	3	42	45	62	886	948	995	49%
Ontario	0	1	1	192	2,037	2,229	2,238	83%
Prairies	95	79	174	516	958	1,474	1,652	57%
Pacific	10	24	34	88	329	417	451	41%
Unknown	1	2	3	5	33	38	41
Totals	114	194	308	891	4,625	5,516	5,840	59%
Aboriginal	114	70%		891	54%		1,007	55%
Non-Aboriginal	194	48%		4,625	61%		4,833	49%
TOTALS	308	54%		5,516	59%		5,840	59%

 

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Footnote

¹ STI includes: genital chlamydia, gonorrhea, syphilis, herpes simplex, genital warts, and any other non-specific STI such as urethriis.

² The policy to ensure an assessment within 48 hours was in effect until 2008; currently the policy is to assess each inmate for essential health care needs within 24 hours.

³ This time frame differs from that recommended in the Canadian Tuberculosis Standards 6th Edition (PHAC, 2007) but was allowed in the surveillance definition used in this report.

⁴ New Admission for this purpose was defined as a new Warrant of Committal in the Offender Management system (OMS). Note that in the institution, a temporary detainee returned to the institution with new charges may be indistinguishable from other temporary detainees returned to general population (this may lead to some misclassification in assigning inmate status between OMS data and Web-IDSS data).

 

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