Outbreaks occur when there is an increase in the number of disease cases, above what would normally be expected within a
specific place or group of people and within a certain period of time. In 2015, 106 outbreaks were investigated by the Maricopa
County Department of Public Health (MCDPH). Of those 106 outbreaks, 23 were later ruled out. This report describes trends and
provides summary statistics for outbreaks that were reported to and occurred only in Maricopa County‡. For information regarding
multi-jurisdictional and national outbreaks, please visit the Arizona Department of Health Services website:
http://www.azdhs.gov/. For more information, please contact the Office of Epidemiology at MCDPH (602) 372-2605.
‡ Outbreaks involving single cases of communicable disease without local transmission are not included in this report. Please visit MCDPH’s Health Statistics and
Reports webpage: http://www.maricopa.gov/publichealth/Services/EPI/Reports/default.aspx.

Characteristics of Reported Outbreaks: Maricopa County, 2015
Year Total*

Number of Persons
Ill per Outbreak†

1 = Minimum
92 = Maximum
8 = Median

83

Total
Persons
Affected by
Outbreaks†

1,236

Demographics
Hospitalizations†

Deaths†

68

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Average % Gender†

45% = Female
30% = Male
25% = Unknown

Age Ranges†

4 (<1%)
31 (2%)
122 (10%)
59 (5%)
64 (5%)
80 (7%)
120 (10%)
746 (61%)

= Less than 1 year
= 1-4 years
= 5-9 years
= 10-19 years
= 20-49 years
= 50-74 years
= >74 years
= Unknown

*23 reported outbreaks were later ruled-out and not included in this summary
†For cases whom information was available

2015 Outbreaks by Etiology
Gastrointestinal

42 (51%) Rash

9 (11%)

Clostridium difficile (C.diff)

1 (2%)

Parvovirus B19 (Fifth Disease)

1 (11%)

E. coli

2 (5%)

Scabies

7 (78%)

Norovirus

14 (33%)

Rash- Unknown Type

1 (11%)

Giardia

1 (2%)

Salmonella

4 (10%)

Respiratory

16 (19%)

Shigella

6 (14%)

Influenza

6 (38%)

Gastrointestinal- Unknown Type

14 (33%)

Legionella

2 (12%)

Respiratory Syncytial Virus (RSV)

1 (6%)

6 (7%)

Strep Throat (Type A, non-invasive)

3 (19%)

2 (33%)
2 (33%)
2 (33%)

Respiratory- Unknown Type

4 (25%)

Other
Conjunctivitis
Hand, Foot, and Mouth Disease
Head Lice

Vaccine-Preventable
Pertussis
Varicella

For more information, please visit our website: http://www.maricopa.gov/PublicHealth/Services/EPI/default.aspx

10 (12%)
9 (90%)
1 (10%)

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Number of Outbreaks Reported by Month 2013-2015
2013 (n=140)

2014 (n=101)

Number of Outbreaks Reported by Type and Month
2015 (n=83)

2015 (n=83)

Gastrointestinal

35

Rash

Respiratory

Vaccine-Preventable

Other

10
9

30

8

Number of Outbreaks

Number of Outbreaks

25
20
15
10

7
6
5
4
3
2

5

1
0
Jan Feb Mar Apr May Jun

Jul

Aug Sep Oct Nov Dec

Month

Number of Outbreaks by Type and Facility 2015 (n=83)
Gastrointestinal

Rash

Respiratory

Vaccine-Preventable

0
Jan Feb Mar Apr May Jun Jul
Month

Aug Sep Oct Nov Dec

Gastrointestinal Outbreaks by Etiology 2015 (n=42)
Other

16
14

E. coli
C. diff 5%
Giardia
2%
2%

Number of Outbreaks

12
10

Salmonella
10%

Norovirus
33%

8

Shigella
14%

6
4

Unknown Type
34%

2
0

Type of Facility

For more information, please visit our website: http://www.maricopa.gov/PublicHealth/Services/EPI/default.aspx

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