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 2016, 125 outbreaks were investigated by the Maricopa
County Department of Public Health (MCDPH). Of those 125 outbreaks, 24 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, 2016
Year Total*

Number of Persons
Ill per Outbreak†

2 = Minimum
459 = Maximum
10 = Median

101

Total
Persons
Affected by
Outbreaks†

2475

Demographics
Hospitalizations†

Deaths†

108

4

Average % Gender†

42% = Female
30% = Male
28% = Unknown

Age Ranges†

30 (1%)
338 (14%)
375 (15%)
182 (7%)
279 (11%)
97 (4%)
175 (7%)
999 (40%)

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

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

2016 Outbreaks by Etiology
Gastrointestinal

74 (73%) Rash

6 (6%)

Cryptosporidium

1 (1%)

Scabies

5 (83%)

Norovirus

20 (27%)

Rash- Unknown Type

1 (17%)

Salmonella

1 (1%)

Shigella

30 (41%) Respiratory

9 (9%)

Gastrointestinal- Unknown Type

22 (30%)

Influenza

3 (33%)

Legionella

1 (11%)

Respiratory- Unknown Type

5 (56%)

Other

3 (3%)

Conjunctivitis

1 (33%)

Hand, Foot, and Mouth Disease

2 (66%)

Vaccine-Preventable
Pertussis
Varicella

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

9 (9%)
6 (66%)
3 (33%)

1

Number of Outbreaks Reported by Month 2014-2016
2014 (n=101)

2015 (n=83)

Number of Outbreaks Reported by Type
and Month 2016 (n=101)

2016 (n=101)

Gastrointestinal
25

Rash

Respiratory

Vaccine-Preventable

Other

16
14

20

Number of Outbreaks

Number of Outbreaks

12
15

10

5

10
8
6
4
2
0

0
Jan Feb Mar Apr May Jun

Jul Aug Sep Oct Nov Dec

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Month

Month

Number of Outbreaks by Type and Facility 2016 (n=101)
Gastrointestinal

Rash

Respiratory

Vaccine-Preventable

Gastrointestinal Outbreaks by Etiology 2016 (n=74)

Other

35

Cryptosporidiosis
1%

Number of Outbreaks

30
25
20

Unknown
Type
30%

15

Norovirus
27%

10
5
0

Shigella
41%

Salmonella
1%

Type of Facility

2
For more information, please visit our website: http://www.maricopa.gov/PublicHealth/Services/EPI/default.aspx