Pandemic H1N1 Influenza among CSC Inmates 2009 – 2010:
Summary of Vaccination Campaign, Cases, and Outbreaks

June 2011

[ Previous Page | Table of Contents | Next Page ]

III: Results

---

III Results – Vaccination Campaign

Number and % of Inmates Identified as Meeting Priority Criteria

CSC Region	# Priority Inmates Identified	Population at Start of Priority Campaign	% Inmates Meeting Priority Criteria
Atlantic	596	1366	43.6%
Québec	923	3234	28.5%
Ontario	1324	3821	34.7%
Prairie	1147	3583	32.0%
Pacific	670	1904	35.2%
Total	4660	13,908	33.5%

RESULT: Overall, a third of inmates met the priority sequencing criteria which ranged from 43.6% in the Atlantic Region to 28.5% in the Quebec Region.

Priority and Overall Vaccination Campaign Coverage Rates by Region

	Priority Vaccination Campaign (late Oct. early Dec. 2009)			Overall (Priority + Mass) Vaccination Campaign (late Oct. 2009 Jan. 2010)
* Equals the number of inmates at the start of the immunization campaign (13,908) plus new admissions during the campaign (679).
CSC Region	# Priority Inmates Identified	# Inmates Immunized	% Priority Inmates Immunized	Cumulative Inmate Population	Total # Inmates Immunized	% Inmate Population Immunized
Atlantic	596	443	74.3%	1433	1101	76.8%
Québec	923	806	87.3%	3388	2080	61.4%
Ontario	1324	1046	79.0%	3964	1612	40.7%
Prairie	1147	1027	89.5%	3787	2268	59.9%
Pacific	670	610	91.0%	2015	1059	52.6%
Total	4660	3932	84.4%	14,587*	8120	55.7%

RESULT: In the priority sequence, 3932 offenders or 84.4% were immunized. In total, 8120 inmates were immunized in CSC (estimated overall coverage 55.7%).

 

Cumulative # of Vaccinations Administered to Inmates (n=8120)*

* Note: graph excludes timeframe outside Oct. 31 – Dec. 18, 2009 when 186 immunizations were given

text version

 

H1N1 Vaccine Coverage Rates

text version

RESULT: For all of the regions except Atlantic, the coverage rates were higher in the priority campaign than for the overall campaign.

 

Average Campaign Length in Days (range)

CSC Region	Priority Vaccination Campaign	Mass Vaccination Campaign
Atlantic	9 (1-29)	3 (1-6)
Québec	11 (2-25)	5 (1-10)
Ontario	12 (2-20)	6 (1-15)
Prairie	8 (1-21)	6 (1-16)
Pacific	10 (1-20)	40 (6-58)
Total	10 (1-29)	12 (1-58)

• Priority campaign:
  • lasted an average of 10 days (range: 1 day – 29 days)
  • average length was shortest in the Prairie Region (8 days) and longest in the Ontario Region (12 days)

• Mass campaign:
  • lasted an average of 12 days (range: 1 day – 58 days)
  • average length was shortest in the Atlantic Region (3 days) and longest in the Pacific Region (40 days)

---

III Results – Influenza Case Definitions

• Influenza-Like-Illness (ILI)
  • Acute onset of respiratory illness associated with fever and cough; and one or more of the following:
    • sore throat; arthralgia; myalgia; prostration

• Laboratory-Confirmed (lab-confirmed) Case
  • Laboratory confirmation of pandemic H1N1 influenza virus infection with or without clinical symptoms by one or more of the following tests:
    
    • RT–PCR (reverse transcriptase-polymerase chain reaction)
      
    • Viral culture
      
    • Four-fold rise in influenza A (H1N1) virus specific neutralizing antibodies

• Epidemiologically-Linked (epi-linked) Case
  • An epi-linked case refers to an individual:
    
    • whose clinical presentation is consistent with influenza like illness AND
      
    • confirmed or suspected contact to a laboratory confirmed case AND
      
    • confirmatory laboratory testing has not been done for this particular individual.

• Clinical Case
  • A case based on the presentation of clinical signs and symptoms consistent with influenza.

• Negative for Influenza
  • A patient who is assessed for influenza but subsequently tests negative.

---

III Results – Influenza Cases and ILI

ILI Case Type distribution by Region

	H1N1 Lab confirmed	Epi-linked/ Clinical	Negative for Influenza	Total
Atlantic	3	14	5	22 (14%)
Quebec	8	2	4	14 (9%)
Ontario	7	11	4	22 (14%)
Prairie	20	7	32	59 (37%)
Pacific	11	11	19	41 (26%)
TOTAL	49	45	64	158 (100%)

All 158 cases are “ILI” by definition; that is, they were “screened-in” based on meeting the symptoms of influenza-like illness.

 

ILI Case Type distribution by Origin and Gender

	H1N1 Lab confirmed	Epi-linked/ Clinical	Negative for Influenza	Total
Origin
Canadian-born non-Aboriginal	28	30	30	88 (56%)
Canadian-born Aboriginal	17	10	32	59 (37%)
Foreign-born	4	5	2	11 (7%)
Gender
Male	48	43	63	154 (97%)
Female	1	2	1	4 (3%)

All 158 cases are “ILI” by definition; that is, they were “screened-in” based on meeting the symptoms of influenza-like illness.

 

Epidemic Curve of H1N1 Influenza Cases* (n=91)

text version

* 3 epi-linked / clinical cases which occurred in 2010 are not shown
** If date of symptom onset not reported, use the earliest of the following: date tested, treatment start date, date case reported.

 

text version

Cases include lab-confirmed , clinical, and epi-linked categories
* Missing symptom information was excluded from the analysis

 

text version

Cases include lab-confirmed , clinical, and epi-linked categories
* Missing risk factor information was excluded from the analysis

 

Symptoms

• Cases reported symptoms more frequently than those negative for influenza
• Fever was not a prominent symptom (only reported by 39% of cases and 29% of those who tested negative for influenza)

Risk Factors

• Most common risk factors for cases: hepatitis / cirrhosis (17%), bronchopulmonary disorders (15%) and age 65+ years (7%).
• Most risk factors were more common among those who tested negative
  • inmates with underlying conditions were more likely to be assessed due to increased risk of poor outcomes

Testing

Nasopharyngeal Swab	Nasal Swab*	Throat Swab*	Serum	Bronchoalveolar Lavage	Chest X-ray	Sputum
* Note: Nasopharyngeal swab is the best way to test for influenza infection (nasal and throat swabs are not recommended). One offender tested positive with a nasal swab while the rest of the nasal/ throat swabs were negative and could represent false negative results.
67% (105)	2.6% (4)	0.6% (1)	0.6% (1)	0.6% (1)	3.2% (5)	1.9% (3)

• Overall % positive for all tested = 44.1%

Severity

Hospitalization**	Isolation	Oxygen Therapy	Pneumonia
** Includes CSC Regional Hospital
3.2% (5)	53% (82)	1.3% (2)	0.6% (1)

• No inmates were ventilated, admitted to the ICU (intensive care unit) or experienced ARDS (acute respiratory distress syndrome)

Treatment

• 53% (n=83) of inmates with ILI were treated with Oseltamivir (Tamiflu).
• Oseltamivir was the only antiviral medication used for treatment.
• No serious adverse events to treatment were reported.

Case Status

• At the time of reporting, 81% (n=113) of offenders were stable and 19% (n=26) were recovering.
• There were no inmates deaths due to H1N1.

 

text version

Inmates who reported symptoms were more likely to be treated with antivirals (Oseltamivir)

 

text version

Inmates who reported risk factors for severity were more likely to be treated with antivirals (Oseltamivir)

---

III Results – Outbreaks

OUTBREAK DEFINITION: Two or more cases of ILI within a seven-day period including at least one lab-confirmed case.

Institution	Region	# cases during outbreak period	Date* outbreak started	Date** of last case in outbreak	Date outbreak ended***
*This is the first reported date of symptom onset ** This is the latest date of symptom onset for the last case in the outbreak *** Outbreaks end 14 days (2 incubation periods) after latest symptom onset of last case
Springhill	ATL	8	Nov. 25	Dec. 20	Jan. 3
Archambault	QUE	6	Nov. 24	Dec. 1	Dec. 15
Centre Régional de Réception	QUE	2	Nov. 12	Nov. 19	Dec. 3
Joyceville	ONT	5	Nov. 7	Nov. 16	Nov. 30
Pittsburgh	ONT	12	Nov. 3	Nov. 18	Dec. 2
Riverbend	PRA	3	Nov. 6	Nov. 16	Nov. 30
Saskatchewan Penitentiary	PRA	15	Nov. 9	Dec. 9	Dec. 23
Matsqui	PAC	7	Nov. 8	Nov. 12	Nov. 26
Pacific/Regional Treatment Centre	PAC	11	Nov. 3	Nov. 12	Nov. 26

Outbreak summary

• There were a total of 9 outbreaks in CSC institutions during the 2009/2010 influenza season
  • All due to the pandemic H1N1 strain
  • 2 outbreaks in each region, except only 1 in Atlantic
• The outbreaks varied in size
  • Smallest was 2 cases at Centre Régional de Réception (QUE)
  • Largest was 15 cases at Saskatchewan Penitentiary (PRA)
• The outbreaks occurred between October 2009 and January 2010
  • Pittsburgh (ONT) and Pacific/Regional Treatment Centre (PAC) outbreaks began first on November 3, 2009
  • Springhill (ATL) outbreak ended last on January 3, 2010
  • The timing of the outbreaks corresponds with the national data from PHAC

[ Previous Page | Table of Contents | Next Page ]