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INFECTIOUS DISEASE SURVEILLANCE
in Canadian Federal Penitentiaries 2005-2006

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Part III: Discussion

Summary of Diseases / Pathogens

Participation in Screening and Testing

As per CSC policy (CSC, 2009a; CSC, 2009b) all inmates are offered screening upon admission for infectious diseases including HIV, HCV, HAV, HBV, STI and TB. Screening is an assessment of risk behaviours by means of a questionnaire and a physical examination. Although this screening is offered to all inmates, some refuse to take part. Inmates are recommended testing services (a blood test) if they are deemed to be at risk for an infectious disease based upon their screening results or if they request a test. The IDSS does not provide information on the number of inmates who accept or refuse screening for infectious diseases; data is recorded only on the number of blood tests drawn. All screening and testing is voluntary, except where an inmate is suspected of having active TB.

Maximum participation in screening and testing for BBSTI is important for several reasons, not least of which is to identify those at risk and detect unknown cases. At the same time, it provides an opportunity for infectious disease nurses to provide counselling and education to inmates on the risk factors, prevention strategies and treatments available for BBSTI. Studies conducted among provincial inmates in Canada suggest that 15-35% are unaware of their HCV infection status (Calzavara, 2007; Poulin, 2007) and between 40-60% for HIV (Rothon et al, 1994; Dufour etal 1996). In 1996 it was estimated that half of all HIV infections among inmates were among those who had not presented to correctional health services (Remis, 2001). Similarly, an estimated 30% of the HIV positive population (PHAC, 2005), and a third of the HCV positive population (Wong, 2006) in Canada are unaware of their status.

HIV and HCV

The IDSS data indicates that about half of new admissions and around 25-30% of general population inmates were screened for HIV in 2005-2006. Likewise, about half of new admissions and 20-25% of general population inmates were screened for HCV during the same timeframe. Testing rates for both pathogens increased sharply from 2000 to 2003 and then remained fairly stable or declined slightly from 2003-2006. The reasons for the slight declines are not clear, however among new admissions it may reflect an increase in previous testing at provincial jails or in the community. For instance, in Ontario it was reported that between 58-75% of detainees had a previous HIV test (Burchell 2003; Calzavara, 2007) while in Quebec the reported figure was 69% (Poulin, 2007). This is consistent with the findings from enhanced surveillance that show 54.2% of new admissions report a previous HIV test. Previous test history is associated with parenteral and sexual risk (Burchell 2003). In CSC, an inmate at low risk is not necessarily recommended for testing, particularly if he or she has tested negative in the past and not reported subsequent risk behaviours. Policies or guidelines for routine annual testing for BBSTI was not in place at CSC during 2005-2006; however, BBSTI testing throughout incarceration is available on request from Health Services at any time. In the United States almost 3 in 4 (77%) of inmates in a State facility reported an HIV test since admission (CDC 2009)

HAV and HBV

After adjusting for the Web-IDSS coverage of new admissions overall, an estimated 32% of New Admissions were tested for HAV and 39% were tested for HBV in 2005-2006. Testing for HAV and HBV provides information about infection status, but more commonly is done to determine vaccination status as both diseases are vaccine-preventable. Serology testing for those with unknown immunity status has been shown to be a more cost-effective strategy than Twinrix® vaccination for all new admissions, as many have been vaccinated in the past or indeed may have acquired natural infection (Smith, 2006). Assuming that immunization for HAV and HBV is done on admission an estimated 60% of new admissions were vaccinated for HAV and/or HBV. However, as these data are based on purchase order data for vaccine by region, it is only an estimate of the immunization coverage and is limited by many factors.

Findings from Web-IDSS indicate that a number of inmates were tested for HAV (n=1,818) and HBV (n=2,053) as general population inmates. It may be that this is reflective of inmates who were missed or who had refused testing during the admission process. This suggests that HAV and HBV immunity and vaccination “catch-up” remains a priority for infectious disease nurses.

STI

Among new admissions, roughly one in five New Admissions was tested for chlamydia and gonorrhea and one in three tested for syphilis. The testing rates for women tended to be higher than for men. There are several reasons why this may be the case. For example, women tend to report more risk factors for BBSTI than men and therefore would be recommended testing at a higher rate (Smith, 2008). Additionally, women may be more open to screening and more likely to accept testing. Although limited, enhanced screening data also indicate that women may have swabs taken during other procedures (such as the Pap test). Screening via a urine test may be more acceptable to males versus a urethral swab, which may increase testing for chlamydia and gonorrhea among males.

Testing uptake among general population inmates for chlamydia (n=1,159), gonorrhea (n=1,079) and syphilis (1,906) is not inconsequential and may be reflective of ongoing risk factors among inmates (Zakaria, 2010). The higher uptake for syphilis may be in part opportunistic as the blood sample may be collected simultaneously for tests for HIV, HCV, HAV and/or HBV.

Regionally, both Prairie and Quebec Regions tended to have higher test uptake than in the other regions for chlamydia and gonorrhea. This may be reflective of the higher STI prevalence in the Prairie provinces in Canada (PHAC, 2010). Several of the institutions in these regions had implemented routine urine screening for chlamydia and gonorrhea in their admission screening process during the surveillance period of 2005-2006. This may in part explain the higher screening uptake among Canadian-born Aboriginal inmates as they account for roughly 40% of the Prairie inmate population.

TB

A high participation in tuberculosis assessment for inmates on admission is important for several reasons: first, it is important to detect any active cases among New Admissions before they can spread infection to other inmates; and second, it is important to establish an accurate baseline tuberculosis status in order to evaluate subsequent assessments and investigations. Among inmates, participation in TB assessment for 2005-2006 is about 80% and it has remained consistently high since 1998. These results are encouraging, as TB remains a concern among the inmate population.

A high participation in staff tuberculosis assessment, especially on hire, is important in order to establish a valid baseline tuberculosis status for each staff member. Staff are the most stable population in an institution and could represent a sentinel population for examining tuberculosis transmission within the entire facility – amongst both inmates and staff. Participation in staff TB assessment is quite low, at 12.4% in 2005 and 17.9% in 2006. This is down from a high of 38.6% in 1998. If a staff member has a TB test done by their personal physician, this would not necessarily be reflected in these data; thus the overall proportion of staff who are aware of their TST status may be underestimated by Web-IDSS.

Infectious Disease Prevalence Estimates

HIV and HCV

The estimated prevalence of HIV among inmates in Canadian federal penitentiaries was 1.67% in 2005 and 1.64% in 2006. HIV prevalence in CSC has remained fairly constant since 1999 and has ranged between 1.5%-2%. The estimated HIV prevalence in the general Canadian population is lower than the CSC rate, at about 0.2% (PHAC 2010). The high prevalence among inmates is attributable to a higher prevalence of risk factors such as sex trade involvement and injection drug use among this population prior to incarceration (Smith 2008; Zakaria 2010).

The total number of newly diagnosed HIV cases was 45 in 2000, 14 in 2005 and 15 in 2006. Among new admissions, the numbers in 2005-2006 were 7 and 8 respectively while the number of inmates known to be HIV positive on admission rose from 104 in 2000 to 155 in 2006. This shows that among those who are known to be HIV positive on admission to CSC, the majority are already aware of their status. This trend has been increasing over time. This likely reflects increasing uptake of HIV testing in the community and/or in provincial and territorial correctional facilities.

The estimated HCV prevalence has risen steadily from 18.1% in 1999 to 29.3% in 2005 and 27.6% in 2006. HCV represents the largest communicable disease burden in CSC, with over 3,500 inmates reporting to be infected in 2005 and 2006. The total number of newly diagnosed HCV cases was 354 in 2005 and 357 in 2006, which is a decrease from 553 in 2000. Similar to HIV, the majority of HCV infected inmates are aware of their status prior to admission to CSC. Among new admissions, there were 178 and 193 newly diagnosed HCV cases in 2005-2006 respectively while the number of inmates known to be HCV positive on admission was 1,034 in 2005 and 1,165 in 2006. These data indicate that provincial and federal inmates appear to be more aware of their HCV status than the general population of Canada.

HCV prevalence is much higher in CSC compared to the general Canadian population, estimated at 0.8% (Remis, 2009). This is attributable to the higher prevalence of a lifetime history of injection drug use prior to incarceration among federal inmates (Burchell 2003; CSC 2008; Zakaria 2010). In Canada, the contribution of injection drug use to the overall reported rate has been estimated at 70-80%; that is, of those with known infection, roughly three-quarters report a history of injection drug use (Wong 2006). As compared to HIV and HBV, sexual transmission of HCV is believed to be uncommon and a much less efficient mode of transmission. Many HCV cases among sex-trade workers and those with multiple partners are attributed to IDU involvement (Wong 2006).

In this report we have introduced, for the first time, Web-IDSS prevalence estimates for HIV and HCV. Compared to IDSS data, it is clear that the Web-IDSS estimate suffers a differential bias as the number of known positive cases on admissions seems under-reported. Based on actual test results, the overall Web-IDSS prevalence estimate for HIV was 0.95%, which is roughly two-thirds of the HIV prevalence estimate from the IDSS data. For HCV, the Web-IDSS prevalence estimate was 31.6% which, albeit higher, is of the same order of magnitude as the IDSS estimate of 29.3%-27.6%. Given the limitations of the Web-IDSS data (discussed below) the IDSS prevalence estimates for HIV and HCV remain the ‘gold standard’.

One benefit of using Web-IDSS data is that it provides an estimate of seroconversion rates for HIV and HCV. In the preceding chapters, we have reported that there were no HIV seroconverters in 2005-2006.However, a crude estimate of 31 HCV seroconversions per 1,000 HCV negative inmates per year can be made.

HAV and HBV

Based on IDSS data, there were no HAV cases in 2005 and only one acute case in 2006. For HBV, there were 6 cases reported in 2005 and 9 reported in 2006. Thus, the acute prevalence rates for HAV and HBV for each year are both below 0.1%. The Web-IDSS results are much higher than the IDSS results with 23 HAV cases detected and 25 HBV cases reported in 2005-2006. One major difference is that IDSS cases are reported by the nurse while the Web-IDSS results are based upon serology results. This may account for the large discrepancies in reported cases between the two surveillance systems. Given that the interpretation of serology results is difficult, especially with respect to HBV, active case results for HAV and HBV from Web-IDSS may be more accurate. More over, there were 12 New Admissions with infectious (active) HAV, which further supports having routine screening upon admission, rather than a symptom-based screening.

Assuming that the Web-IDSS data for 2005-2006 are representative of admission cohorts, roughly a third of new admissions are immune to HAV and/or HBV infection. In addition among general population inmates 4 of 10 were immune to HAV and 5 in 10 HBV. Combined with the information that another ~2,800 or so inmates are vaccinated against HAV and HBV, and assuming that even in the absence of an electronic health record, serology tests among general population inmates were not done among those immunized on admission or whose status was already known, these results indicate high herd immunity for both HAV and HBV.

STI

The observed increase in STI prevalence among inmates at CSC is mirrored by increases in the general Canadian population (PHAC, 2010). However, the prevalence rates for STI among inmates from the IDSS are higher compared with the Canadian population in general. In CSC, the overall prevalence rate of chlamydia is more than three times greater than the Canadian rate (2006: 720 vs 212 per 100,000 respectively) and for gonorrhea is more than four times greater (2006: 150 vs 35 per 100,000). For syphilis, the rise in the number of cases from 0 in 2000-2001 to 16 in 2006 is a concern. Compared to the Canadian infectious syphilis rate, the CSC rate of reported syphilis was 30 times higher (2006: 120 vs 4 per 100,000 respectively). Caution in comparison is warranted since staging of syphilis was not available in the CSC surveillance data. The higher rates of STI can be attributed to a high prevalence of sexual risk factors among inmates prior to admission (Smith 2007; Smith 2008, CSC 2008) and to risk factors during incarceration (Okie 2007; Zakaria 2010).

The prevalence of bloodborne and sexually transmitted infections (BBSTI), including HIV, HCV and STI are higher among female inmates when compared to males. Since women are more likely to participate in screening compared to men, the higher prevalence may be due in part to increased case finding. However, women who are incarcerated are also at a higher risk of infection compared to men, due to a history of sexual and physical abuse, injection drug use, and sex-trade work (Braithwaite 2005; CSC 2008; Smith 2008). Incarcerated women have reported a higher history of injection drug use and a higher prevalence of infection compared to men in several studies (Calzavara 1995; Dufour 1996; Rothon 1997; Calzavara 2007; Poulin 2007; Moloughney 2004).

The observed variability of BBSTI prevalence by region may be due to a number of factors such as regional or provincial differences in screening and testing. However, it may also be due to true underlying prevalence differences of infection among inmates by province or region. This is supported by the fact that there are regional variations in test positivity and in the estimated prevalence of BBSTI (particularly HIV and HCV) among New Admissions. This is likely a reflection of the underlying variation in prevalence rates across provinces in Canada.

BBSTI prevalence also varies by origin, likely due to many of the same factors. For example, one reason why Canadian-born Aboriginal inmates have higher prevalence rates is because they often have higher testing rates and therefore increased case finding. Furthermore, Aboriginal inmates tend to report higher rates of risk factors than non-Aboriginal inmates (CSC 2008; Smith 2008) and it is likely that underlying prevalence rates differ by origin. It is also important to note that differences by region and origin can be difficult to distinguish as some regions have different offender profiles. For example, Aboriginal offenders are overrepresented in the Prairies region (see Table 1.2.i), which make it difficult to determine differences in prevalence rates that are due to region or origin without a more detailed analysis of the data.

TB

The proportion of inmates with a positive TST on admission has steadily declined from 21.3% in 1998 to 13.3% in 2006. The proportion of invalid assessments has remained between 11-13%, which suggests ongoing operational constraints in completing the initial assessment in the correctional environment. The proportion of staff with a positive TST on initial assessment was less than 10% and the proportion of tests that are invalid is very high (25.9% in 2005 and 17.8% in 2006). This has been attributed to difficulties in completing four clinical visits among staff who work rotating nights / days or hours and shift work. In 2009, staff participation was addressed by a joint pilot project between CSC, PHAC, and Health Canada. Initial results suggest that by increasing resources for TB assessments and ensuring support for nursing clinics at the institutional, regional and national levels in CSC can significantly increase participation.

The TST conversion rate among inmates has remained fairly stable at ~0.9% between 2004 and 2006. Although based on small numbers, the TST conversion among staff has steadily increased from 2001 to 2005. Together, these results may indicate ongoing TB transmission in CSC institutions among and/or between inmates and staff. It may also be that observed TST conversions are due to exposure to undiagnosed or sub-clinical cases of infectious TB inside CSC, or due to exposures to an infectious TB case outside the institution (i.e., prior to admission in the case of an inmate, or in the community in the case of a staff member). Indeed, there were 7 active TB cases reported among inmates in 2005 and 3 in 2006. While reporting follow up on active TB contact investigations is outside the scope of this report, further investigation into TB transmission between and among inmates and staff following exposure to infectious cases of active TB are being conducted.

The estimated prevalence of latent tuberculosis infection (LTBI) among inmates has been declining since 1998, with a small increase from 2005 to 2006. Despite this, the prevalence remains high compared to the general population in Canada (Yuan, 2007). LTBI rates are higher in men than in women and increase with age. Aboriginal and Foreign-born inmates were more likely to have LTBI, and the observed differences in regional LTBI rates may be explained in part by the differing demographic profile of the regions.

The observed LTBI prevalence among staff for 2005-2006 was also higher than the Canadian general population in general, although it has decreased substantially since 1998. This may be explained by a higher risk of acquiring LTBI among staff working in institutions. However, the low participation rate makes interpretation difficult. It may be, for instance, that those who perceive themselves to be at higher risk (i.e., who are involved in contact investigations, or those with an identified exposure) come forward for testing. This would result in a biased estimate.

The observed ethnic differences in LTBI prevalence for inmates and staff do not appear to be related to age-at-BCG vaccination. Self-reported history of BCG at initial assessment among staff was higher than for inmates, while the prevalence of LTBI was lower. However, among both inmates and staff with a positive TST result on initial assessment, a higher proportion reported a history of BCG.

While this may suggest a relationship between BCG status and TST result, it is important to note several limitations in interpretation. First, BCG status was self-reported and may be subject to recollection bias between the two populations (i.e., staff may be more likely to recall a previous BCG vaccination). Second, it is unclear whether, among inmates and staff, it was presumed by CSC and / or PHOSP nurses that a BCG history was a contraindication for TST testing, and whether the positive TST result was implied or imputed; data entry rules in the legacy application were such that a TST reading was required so it is impossible, without a detailed file review, to determine whether the observed association between TST result and BCG history in these data is a true association or a data entry anomaly.

The number of active TB cases diagnosed and reported in CSC between 1998 and 2008 varied from zero to 7. This rate is statistically unstable since it is based on small numbers; however, with the exception of 2001 (when there were no cases), the case rate per 100,000 among inmates was higher than the Canadian rate.

Previously reported tuberculosis surveillance results for 1998 – 2004 have been updated within this report (CSC 2001; CSC 2005; CSC 2008). While overall trends did not change, it is important to point out that tuberculosis surveillance data will continue to be updated in subsequent reports. The reasons for the updates and changes to the data include routine data quality and data validity processes (i.e., reassignment of assessments from unknown categories) and the addition of records to the data.

Treatment

IDSS data is available for the number of inmates initiated on therapy and on treatment for HIV, HCV and LTBI in a given month. For HIV and HCV, the treatment uptake is calculated although these rates are subject to the limitations of the data (see Limitations below). Web-IDSS data is available for previous treatment of HIV, HCV and STI; however, these data are subject to recall bias. Although treatment forms for HIV, HCV, STI and LTBI were in place, they were not fully implemented in the institutions during 2005-2006; thus these data are not included in this report. Despite the limitations, the testing data from IDSS included in this report provides some valuable information, particularly with regards to nurse workload.

On average, in a given month in 2005-2006, there were roughly 100 inmates on LTBI therapy, over 110 on anti-retroviral therapy for HIV and roughly 150 on HCV treatment. In 2006, 70 inmates were initiated on anti-retroviral therapy and 370 were initiated on HCV therapy. The treatment uptake was estimated to be over 50% for HIV and roughly 4-5% for HCV. This equates to a large workload for CSC nurses because the time and effort required to initiate inmates on these complex regimens and to monitor their progress over many months, if not years, is substantial. Of note, there are gender differences in treatment uptake for HIV and HCV which warrant further analysis.

Limitations

The data presented in this report are subject to a number of limitations. The IDSS data are aggregate and rely on nurses to fill in the data at the end of each month. In the absence of a standardized electronic health record, this is a pencil and paper task. Tracking inmate transfers on a monthly basis requires a review of transfer lists and cross-referencing this against other lists by hand. In addition, there are some instances which are not captured by the IDSS workbooks (i.e., an HCV case who is transferred to a provincial facility for court, or to a community hospital), which may lead to differences in how the data are recorded between institutions. Since the IDSS data are aggregate institutional data, “gender” was determined according to institution; since females are sometimes housed for short periods of time in male institutions, this may lead to some, albeit negligible, misclassification bias. Note that due to discrepancies in data due to the accumulation of transfers in and out of institutions, and releases to the community, the data do not match exactly from year-end to the start of the next year.

An administration guide for the IDSS workbooks is updated on an annual basis. While there is no training per se on the IDSS worksheets, there is constant dialogue between National Headquarters (NHQ) and the Regions, presentations at regional infectious disease meetings, and dialogue on specific questions via email or other means on specific issues.

The categorization of inmates into ‘new admission’ and ‘general population’ may result in some misclassification error. In some instances, new admissions may be immediately removed to segregation, either as result of their security classification or as a result of behaviour. In this case, the inmate is not necessarily available to health services, and special arrangements must be made to ensure the nurse conducts the health assessment in light of the security considerations.

It may also happen that an inmate is interviewed and tests are requested while this inmate is in an admission unit, but the test results are not received until the inmate has transferred out to another institution (now considered a general population inmate). If the institution receiving the test results reports the results, the test would be counted for a general population inmate rather than a new admission. Unlike male inmates, a single institution handles admissions and multiple security levels for females; therefore, the distinction between ‘new admission’ and ‘general population’ is less clear. The observed screening rates reported for female institutions in Prairies, Ontario and Quebec for new admissions and general population inmates may be indicative of this type of misclassification (Appendix A, Table A.1.ii; Appendix B, Table B.1.ii).

Treatment data are recorded in the IDSS as the number of inmates on treatment for HIV, HCV or LTBI each month. Please note that antimicrobial treatment is indicated for all untreated chlamydia, gonorrhoea and syphilis cases, antiviral treatment in the community is indicated for some categories of HIV, HBV and HCV infections. The analysis of this data is limited because, except in the case of HIV where treatment is usually lifelong, the treatment will be discontinued after a period of time. As such, estimates for treatment uptake for HCV or LTBI, are limited in the information they provide. Thus, the treatment data presented for HCV and LTBI in this report is most useful for providing information about health services workload as inmates receiving these treatments tend to require close monitoring and significant contact with the nurse, an institutional physician and a specialist physician. Treatment data submitted via the Web-IDSS are also limited, as it is clear that forms were not submitted for many of the inmates who received treatment in 2005-2006. In the future, if these forms are consistently submitted, the Web-IDSS will produce better estimates for treatment uptake than the IDSS.

A major source of variability in the tuberculosis screening data comes from the tuberculin skin test itself. Inter-operator variability in tuberculin administration and in reading the resulting indurations may result in differences in TST outcomes. There may also be some variation in the interpretation of the test (i.e., what constitutes a positive result). Cold-chain protocols must also be strictly followed in order to preserve the integrity of the purified protein derivative; failure to do so may result in false negative test results.

The Web-IDSS application relies on the centralized data entry of hard copies submitted to National Headquarters. Data entry errors may result in misclassifications of records into categories (i.e., ongoing negative rather than ongoing positive), or in attributing TST outcome (i.e., in TST result size). The exact data entry related error rate is unknown. However, routine data consistency checks are applied on a regular basis. In addition, it has been shown (see Chapters 2 and 3) that although the data captured by Web-IDSS is reflective of those screened on admission and newly diagnosed with HIV and HCV, it is less representative of those with prevalent infection on admission. The Web-IDSS for 2005 and 2006 do not appear to be generalizable to those general population inmates tested because of missing data. This gap in surveillance information has been identified and is being addressed.

Future Directions

The correctional environment is an opportunity for public health interventions, including screening, testing, immunization and treatment of infectious disease in a population at risk and otherwise under-serviced (Bick, 2007). The prevalence of bloodborne and sexually transmitted infections and tuberculosis among inmates remains a concern for CSC. The average length of stay in a federal facility in 2005-2006 was three years. It is important for public health in Canada to ensure that prisons are not ‘amplifiers’ of infectious disease, thus a more detailed investigation into the actual incidence of infection while in prison is needed. CSC remains committed to the prevention and control of infectious diseases among incarcerated populations in Canada.

In 2003, Correctional Service Canada entered into a Memorandum of Understanding with the Centre for Infectious Disease Prevention and Control (CIDPC), Public Health Agency of Canada (PHAC, then Health Canada). This collaboration between the two departments in the surveillance and control of tuberculosis now includes HIV/AIDS, viral hepatitis, sexually transmitted infections, and communicable diseases causing respiratory outbreaks. PHAC provides epidemiological and data management services for the collection and analysis of surveillance data as well as expertise and consultation in the prevention and control of infectious diseases. In 2011 CSC and PHAC signed an interdepartmental letter of agreement (ILA) updating the relationship to reflect the maturity of public health capacity at CSC and expanded to include public health services on influenza and pandemic planning. Collaboration between PHAC and CSC remains central to the provision of an effective and efficient public health program in the correctional environment.

This report includes, for the first time, the enhanced surveillance Web-IDSS data from 2005 and 2006. While the data are subject to a variety of limitations and are not complete for the 2005-2006 timeframe (2005 was a ramp-up year) they still represent an important source of information on infectious diseases risk factors, testing, prevalence and treatment in the federal inmate population. Eventually the Web-IDSS will replace the IDSS; however until then the IDSS data is considered the ‘gold standard’ and estimates of prevalence will be based on these data. Another limitation of the aggregate surveillance data is that they do not allow estimates of co-infection. Using Web-IDSS data, an enhanced analysis of co-infection will be conducted.

Based on a review of the admissions process at CSC, including the enhanced screening for infectious disease, the surveillance forms were revised in 2008 and Web-IDSS has been updated to include these revisions. In addition, plans are underway to enable access to electronic surveillance data by nurses in the institutions. Access to previous testing history and results will support continuity of care for inmates in transition from institutions to the community and vice versa.

Implementing the Web-IDSS system, establishing analysis and reporting processes for the data, and conducting an evaluation of the Web-IDSS data have been time consuming and have contributed to the delay in releasing the surveillance data for 2005-2006. Future surveillance data, starting with 2007-2008 will be published in a “pre-release” format as an overall summary data to provide information on overall trends to stakeholders and partners with CSC in public health. Full reports, including detailed IDSS and Web-IDSS data, will follow.

 

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