Epidemiology Data & Reports

The Public Health Department investigates individual cases and outbreaks of reported infectious disease. The team monitors disease trends, conducts data analysis and provides current statistics and other information to health care providers, hospitals, the public and news media. Case counts may change as case investigations are completed.

Annual Disease Counts

DISEASE 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022
AIDS * * 5 <5 <5 <5 5 <5 <5 <5
Campylobacteriosis 79 72 75 62 70 47 53 35 45 79
Chlamydia 982 1029 1075 1137 1257 1190 1143 1044 974 818
Coccidiodomycosis  (Valley Fever) 59 30 67 265 445 353 282 183 180 147
Cryptosporidiosis 5 8 6 8 9 9 8 <5 <5 13
E. Coli 13 14 11 16 16 14 18 20 19 26
Giardiasis 7 10 16 10 9 7 12 <5 11 8
Gonorrhea 63 149 168 231 179 189 185 155 207 203
Hepatitis B  29 25 29 21 35 17 26 18 19 10
Hepatitis C (Community)  396 415 316 325 270 243 208 156 134 97
Hepatitis C (Correctional) 99 81 60 64 97 141 144 73 82 44
HIV * * 16 18 8 16 15 5 10 17
Legionellosis 0 0 0 <5 <5 <5 <5 <5 9 7
Meningitis (All) 19 17 26 15 20 23 14 8 7 13
Pertussis 14 39 19 26 14 13 18 5 <5 <5
Salmonellosis 42 39 50 41 28 21 29 22 27 46
Shigellosis <5 7 9 <5 8 13 7 <5 8 7
Syphilis (All) 22 34 45 53 53 64 66 41 65 100
Tuberculosis (Active)  <5 <5 <5 <5 5 <5 7 <5 5 0
Tuberculosis (Latent)  5 10 12 21 9 <5 19 14 25 26
Vibriosis <5 <5 <5 0 <5 6 0 <5 <5 8

FAQs

You may notice that disease case counts sometimes change over time and local numbers sometimes differ from state reports for the same time period. The reasons involve state and local systems used to report, track and de-duplicate data. 

State review. Case counts most often change over time for chronic reportable diseases, those that stay with a patient for years or even a lifetime. In these cases, health care providers or labs in different counties may report the same patient’s illness to different local health departments. This commonly happens when a patient travels to see a specialist or lives near the border of two counties, such as in Santa Maria, and gets health care in both. While each local health department only has access to their own data and cannot see this duplication, the state department of public health reviews cases from all counties and de-duplicates cases reported in multiple jurisdictions. This review leads to revised local numbers, often a year or more after initial reporting.

Local review. In other cases, numbers may change after local review. For example, state reports on opioid deaths are based on ICD-10 codes. Locally, our epidemiologist also closely reviews death certificates and specific information sources (such as coroner’s toxicology reports) and may identify additional cases through this review. In a common example, a death may be coded as a cardiac arrest, when in fact the cardiac arrest was caused by opioid overdose. This review is important in understanding the local epidemiology of an illness or injury, and is particularly relevant given SLO County’s relatively small population. 

ACTION for Healthy Communities
"What is the quality of life like in San Luis Obispo County? Do residents feel safe? Are there enough employment opportunities?" These are the questions a collaborative group of organizations asks every three years to assess the quality of life in San Luis Obispo County.

​SLO Health Counts
SLO Health Counts is a health data hub that makes local health information easy to find and easy to understand. 

CA Department of Finance Demographic Forecasts
The California Department of Finance provides the most accurate demographic data and population forecasts for the region.

CHIS
The California Health Interview Survey (CHIS) is a survey of all Californians conducted every other year through UCLA to collect data on selected health indicators from various age groups in California. The data is collected and reported on a central website, and available for comparison across years of the survey.

STD Data
The California Department of Public Health provides STD summary tables to track county, California and national rates.

U.S. Census Data
The U.S. Census Bureau collects and reports on a variety of data about America's changing population, housing and workforce through the U.S. Census, the American Community Survey, the Economic Census, and more.