SAN DIEGO COUNTY INFLUENZA SURVEILLANCE

2018-19 SEASON

RESULTS AS OF WEEK 18 (ENDING 5/4/2019)

5/8/2019

9,373

168 Flu Deaths

Outbreaks

TOTAL REPORTED INFLUENZA CASES

CURRENT UPDATEReported Since July 1, 2018

Preliminary Results

Data Source: Reported Influenza Case Reports

Prepared by County of San Diego, Health & Human Services Agency,

Public Health Services, Epidemiology and Immunization Services Branch

5/8/2019

86.9%

5.3%1.7%

4.9% 1.1%Influenza A

Influenza A (H1N1)pdm09

Influenza A (H3) Seasonal

Influenza B

Influenza B/Yamagata

Influenza B/Victoria

Influenza A/B

27

Pediatric Death

INFLUENZA SURVEILLANCE UPDATE, 2018-19 YTD

5/8/2019

Preliminary Results

Data Source: Reported Influenza Case Reports

Prepared by County of San Diego, Health & Human Services Agency,

Public Health Services, Epidemiology and Immunization Services Branch

Week 18 Week 17

Total To

Date Week 18

Total To

Date Week 18

Total To

Date

All influenza detections reported (rapid or PCR) 86 114 9,373 32 20,767 36 10,826

Percent of emergency department visits for ILI 3% 3% 2% 2%

Percent of deaths registered with pneumonia and/or influenza 7% 6% 6% 7%

Number of influenza-related deaths reported^ 1 0 68 1 342 1 164Influenza season is July 1 - June 30, Weeks 27-26. Total deaths reported in prior seasons: 342 in 2017-18, 87 in 2016-17, and 68 in 2015-16.* Previous weeks case counts or percentages may change due to delayed processing or reporting.** Includes FYs 2015-16, 2016-17, and 2017-18.

Current FY deaths are shown by week of report; by week of death for prior FYs.

Indicator

2018-19 Season 2017-18 Season

Prior 3-Year

Average**

Table 1. Influenza Surveillance Indicators.

5/8/2019

Preliminary Results

Data Source: Reported Influenza Case Reports

Prepared by County of San Diego, Health & Human Services Agency,

Public Health Services, Epidemiology and Immunization Services Branch

INFLUENZA SURVEILLANCE UPDATE, 2018-19 YTD

Table 2. Influenza Detections Reported, FY 2018-19*

Positive Test Type/Subtype Week 18 Week 17 Total FYTD Percent FYTD

Influenza A 67 81 8,148 86.9%

Influenza A (H1N1)pdm09 2 1 497 5.3%

Influenza A (H3) Seasonal 1 6 164 1.7%

Influenza B 15 22 455 4.9%

Influenza B/Yamagata 0 0 1 0.0%

Influenza B/Victoria 0 0 3 0.0%

Influenza A/B 1 4 105 1.1%

Total 86 114 9,373 100.0%

* Season is July 1 - June 30

5/8/2019

Preliminary Results

Data Source: Reported Influenza Case Reports

Prepared by County of San Diego, Health & Human Services Agency,

Public Health Services, Epidemiology and Immunization Services Branch

5/8/2019

0

2

4

6

8

10

12

14

16

27 29 31 33 35 37 39 41 43 45 47 49 51 1 3 5 7 9 11 13 15 17 19 21 23 25

Pe

rce

nt

of

Eme

rge

ncy

De

par

tme

nt

Vis

its

Week Number

Figure 2. Percent of Emergency Department Visits for ILI Chief Complaint by Week and Season.

Preliminary Results

Data Source: Reported Influenza Case Reports

Prepared by County of San Diego, Health & Human Services Agency,

Public Health Services, Epidemiology and Immunization Services Branch

5/8/2019

Preliminary Results

Data Source: Reported Influenza Case Reports

Prepared by County of San Diego, Health & Human Services Agency,

Public Health Services, Epidemiology and Immunization Services Branch

0

100

200

300

400

500

600

700

800

27 29 31 33 35 37 39 41 43 45 47 49 51 1 3 5 7 9 11 13 15 17 19 21 23 25

Nu

mb

er

of

Cas

es

Week Number

Figure 3. San Diego County Influenza Detections by Type and Week of Report, 2018-19 FYTD (N=9,373).

Influenza A Influenza A(H1N1)pdm09 Influenza A(H3) Influenza B Influenza B/Victoria Influenza B/Yamagata Influenza A/B

5/8/2019

Preliminary Results

Data Source: Reported Influenza Case Reports

Prepared by County of San Diego, Health & Human Services Agency,

Public Health Services, Epidemiology and Immunization Services Branch

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

2014-15 2015-16 2016-17 2017-18 2018-19

Pe

rce

nt

Season

Figure 4. Proportion of Influenza Detections by Age and Season, 2014-15 to 2018-19.

<1 1-9 yrs 10-19 yrs 20-39 yrs 40-59 yrs 60-79 yrs 80+ Missing

0

5,000

10,000

15,000

20,000

25,000

27 29 31 33 35 37 39 41 43 45 47 49 51 1 3 5 7 9 11 13 15 17 19 21 23 25

Cu

mu

lati

ve N

um

be

r In

flu

en

za R

ep

ort

s

Week Number

Figure 5. Cumulative Influenza Case Reports by Episode Week & Season.

2018-19 2017-18 2016-17 2015-16 2014-15 2013-14

2012-13 2011-12 2010-11 2009-10 2008-09

5/8/2019

Preliminary Results

Data Source: Reported Influenza Case Reports

Prepared by County of San Diego, Health & Human Services Agency,

Public Health Services, Epidemiology and Immunization Services Branch

INFLUENZA SURVEILLANCE UPDATE, 2018-19 YTD

5/8/2019

Preliminary Results

Data Source: Reported Influenza Case Reports

Prepared by County of San Diego, Health & Human Services Agency,

Public Health Services, Epidemiology and Immunization Services Branch

0

2

4

6

8

10

12

14

16

27 34 41 48 3 10 17 24 31 38 45 52 6 13 20 27 34 41 48 3 10 17 24 31 38 45 52 7 14 21 28 35 42 49 4 11 18 25

Pe

rce

nt

of

Em

erg

en

cy D

ep

art

me

nt

Vis

its

Figure 6. Percent of San Diego County Emergency Department Visits for Influenza-like Illness by Week and Season Compared to

5-Year Baseline & Upper 95% Threshold Values (Serfling Method).

ILI% Baseline Upper 95% Threshold

2013-14 2014-15 2015-16 2016-17 2017-18 2018-19

INFLUENZA SURVEILLANCE UPDATE, 2018-19 YTD

5/8/2019

Preliminary Results

Data Source: Reported Influenza Case Reports

Prepared by County of San Diego, Health & Human Services Agency,

Public Health Services, Epidemiology and Immunization Services Branch

0

2

4

6

8

10

12

14

16

18

27 41 3 17 31 45 6 20 34 48 10 24 38 52 14 28 42 4 18 32 46 8 22

Pe

rce

nt

of

De

ath

s

Figure 7. Percent of San Diego County Deaths Registered with Pneumonia and/or Influenza by Week and Season Compared to Prior

5-Year Baseline & Upper 95% Threshold Values (Serfling Method).

%P&I Deaths Baseline Upper 95% Threshold

2013-14 2014-15 2015-16 2016-17 2017-18 2018-19

INFLUENZA SURVEILLANCE UPDATE, 2018-19 YTD

5/8/2019

Preliminary Results

Data Source: Reported Influenza Case Reports

Prepared by County of San Diego, Health & Human Services Agency,

Public Health Services, Epidemiology and Immunization Services Branch

0

50

100

150

200

250

300

350

400

2007

-08

2008

-09

2009

-10

2010

-11

2011

-12

2012

-13

2013

-14

2014

-15

2015

-16

2016

-17

2017

-18

2018

-19

Nu

mb

er

of

De

ath

s

Season

Figure 8. Influenza Deaths by Type and Season.

Both Influenza A and Influenza B

Influenza A/B, Type Unknown

Influenza B

Pandemic H1N1

Influenza A/H3

Influenza A, No Subtype

68

97

7065

1425

342

58

9 8

8768

INFLUENZA SURVEILLANCE UPDATE, 2018-19 YTD

5/8/2019

Preliminary Results

Data Source: Reported Influenza Case Reports

Prepared by County of San Diego, Health & Human Services Agency,

Public Health Services, Epidemiology and Immunization Services Branch

0

50

100

150

200

250

300

350

400

20

07

-08

20

08

-09

20

09

-10

20

10

-11

20

11

-12

20

12

-13

20

13

-14

20

14

-15

20

15

-16

20

16

-17

20

17

-18

20

18

-19

Nu

mb

er

of

De

ath

s

Season

Figure 9. Influenza Deaths by Age and Season.

<1 yr

1-17

18-34

35-64

65+

342

87

68

97

7065

1425

58

89

68

5/8/2019

Preliminary Results

Data Source: San Diego Immunization Registry

Prepared by County of San Diego, Health & Human Services Agency,

Public Health Services, Epidemiology and Immunization Services Branch

INFLUENZA SURVEILLANCE UPDATE, 2018-19 YTD

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

80,000

90,000

27 29 31 33 35 37 39 41 43 45 47 49 51 1 3 5 7 9 11 13 15 17 19 21 23 25

Nu

mb

er

of

Infl

ue

nza

Vac

cin

es

Week Number

Figure 10. Number of Influenza Vaccinations Administered* by Week and Season.

2014-2015 2015-2016 2016-2017 2017-2018 2018-2019

5/8/2019

Preliminary Results

Data Source: San Diego Immunization Registry

Prepared by County of San Diego, Health & Human Services Agency,

Public Health Services, Epidemiology and Immunization Services Branch

INFLUENZA SURVEILLANCE UPDATE, 2018-19 YTD

0

100,000

200,000

300,000

400,000

500,000

600,000

700,000

800,000

900,000

1,000,000

27 29 31 33 35 37 39 41 43 45 47 49 51 1 3 5 7 9 11 13 15 17 19 21 23 25

Nu

mb

er

of

Infl

ue

nza

Vac

cin

es

Week Number

Figure 11. Cumulative Number of Influenza Vaccinations Administered* by Week and Season.

2015-2016 2014-2015 2016 - 2017 2017 - 2018 2018 - 2019

2014-2015 Total: 258,724

2015-2016 Total: 526,5522016-2017 Total: 601,156

2017-2018 Total: 770,0582018-2019 Total: 945,703

5/8/2019

Preliminary Results

Data Source: Reported Influenza Case Reports

Prepared by County of San Diego, Health & Human Services Agency,

Public Health Services, Epidemiology and Immunization Services Branch

INFLUENZA SURVEILLANCE UPDATE, 2018-19 YTD

0

2

4

6

8

10

12

14

16

18

27 29 31 33 35 37 39 41 43 45 47 49 51 1 3 5 7 9 11 13 15 17 19 21 23 25

Pe

rce

nt

of

ED V

isit

s w

ith

Ch

ief

Co

mp

lain

t

Week Number

Figure 12. Percent of Emergency Department Visit Chief Complaints for Cough, Cold, Fever, or

Respiratory Symptoms by Week.

Cough Cold Symptoms Fever Respiratory Symptoms

5/8/2019 Prepared by County of San Diego, Health & Human Services Agency,

Public Health Services, Epidemiology and Immunization Services Branch

INFLUENZA SURVEILLANCE UPDATE, 2018-19 YTD