Zoonotic Diseases*

Zoonoses are diseases transmissible from animals to humans. Although there are over 150 recognized zoonoses, those of significance to Texas include:

• Human Cases of Reportable Zoonotic Diseases in Texas 2020-2023 page
• Human Cases of Reportable Zoonotic Diseases in Texas 2000-2009 page
• 2000-2019 Human Cases of Reportable Zoonotic Diseases in Texas (Excel table)
   

NOTE: These data reflect only those cases reported to the Department of State Health Services. The actual incidence of these diseases in the state may be higher.

¹California encephalitis/meningitis refers to all California serogroup viruses. California serogroup includes California encephalitis, Jamestown Canyon, Keystone, La Crosse, snowshoe hare, and trivittatus virus.
²Denotes “Ehrlichiosis/Anaplasmosis – undetermined,” used when a case has compatible clinical criteria with laboratory evidence to support infection, but without sufficient clarity to identify the causative organism as E. chaffeensis, A. phagocytophilum, or E. ewingii.

³Rickettsiosis, unspecified replaced "dual reporting" in typhus/spotted fever cases in 2015.
⁴The case definition for Rocky Mountain Spotted Fever was changed to Spotted Fever Rickettsiosis in 2010 to capture cases due to other spotted fever Group Rickettsia species, such as Rickettsia parkeri. Commonly available serologic tests are unable to differentiate between spotted fever group Rickettsia species.
⁵Tick-borne Relapsing Fever was not a reportable condition from 2016-2020; cases were reported during these years in the reporting category of "outbreak, exotic disease, or unusual group expression of disease that may be of public health concern."
 NR = Not Reportable. 

*The purpose of surveillance is to try to detect where disease organisms, such as bacteria and viruses, occur in Texas. Rabies surveillance for example is basically an observation or watch for the virus that causes rabies. When an animal is exhibiting the signs of rabies, the brain may be submitted to an approved laboratory for testing. Animals that have bitten or otherwise may have exposed a person or a domestic animal to the virus should also be tested. If an animal is positive, it means that the virus was found during testing. If an animal is negative, it means that the virus was not found during testing. Similar surveillance is conducted on samples from animals for a variety of diseases. The amount of testing in the surveillance process will vary for different counties statewide. If a report indicates that an area does not have any positive test results for a particular disease, it does not necessarily mean that the disease organisms are not in that area. It just reflects the fact that either there were no samples submitted from that area or that submitted samples were negative.