Consideration of Vector-Borne and Zoonotic Diseases During Differential Diagnosis

Steven T. Peper, PhD; Adam C. Jones, PhD; Cynthia Reinoso Webb, PhD; Mark Lacy, MD; Steven M. Presley, PhD


South Med J. 2021;114(5):277-282. 

In This Article

Abstract and Introduction


Objective: Recognition and reporting of vector-borne and zoonotic disease (VBZD) cases is largely dependent upon the consideration of such diseases by healthcare practitioners during the initial diagnosis and ordering of specific confirmative diagnostic tests. This study was conducted to assess the general knowledge and understanding of VBZD transmission and clinical presentation.

Methods: Healthcare practitioners were surveyed to determine the extent of training and educational experiences they received relative to VBZDs, and their likelihood to consider such diseases during differential diagnoses. In addition, an assessment of their knowledge of arthropod species that may transmit VBZD pathogens was conducted.

Results: Having postprofessional school training relevant to VBZDs significantly influenced diagnostic accuracy for such disease cases based on the presented clinical signs and symptoms.

Conclusions: The prevalence of VBZDs in the United States likely is significantly underestimated. The authors suggest the enhancement of VBZD-focused education as an important initiative that would significantly improve timely diagnosis, treatment, and, ultimately, prevention of these diseases.


The Centers for Disease Control and Prevention reported in 2018 that the incidence rate of vector-borne and zoonotic diseases (VBZDs) more than tripled during the past 15 years in the United States, with nine new arthropod-vectored pathogens identified or introduced during that time period.[1] The World Health Organization estimates that half of the world's population is at risk of contracting a vector-borne disease.[2] Of the >1400 identified infectious pathogens known to cause disease in humans, >300 are of clinical importance, and at least 88 are known to be vector borne.[3,4] Vector-borne diseases are spreading in their geographic ranges at an alarming rate, and this rapid spread significantly increases the threat to global public health.[2,5]

Recognition, diagnosis, and reporting of VBZD cases is largely dependent upon a healthcare practitioner's willingness to consider such diseases during initial patient assessment and the ordering of specific confirmatory diagnostic tests. We suggest that a healthcare practitioner's consideration of a VBZD is largely dependent on the scope of VBZD-specific education received during professional training. Lack of knowledge and understanding of the evolving epidemiology of VBZDs and respective potential vectors likely contributes to the underreporting of these diseases in the United States.[6] To gain a better understanding of causes of this knowledge gap, an assessment of the extent of training and education healthcare practitioners received specific to the biology, distribution, and transmission dynamics of VBZDs is critical. It also is important to determine the likelihood of healthcare practitioners to consider VBZDs based on the specific clinical signs and symptoms presented by a patient during his or her initial assessment.

To explore this perceived knowledge gap relative to recognition and clinical diagnosis of VBZDs, we surveyed local healthcare practitioners from Lubbock, Texas to determine their training and experience relative to such diseases and their likelihood to consider them during initial differential diagnoses of patients. We also assessed healthcare practitioner knowledge of arthropods that are potential vectors of VBZD pathogens, and their recognition that patient exposure (ie, fed upon) to specific vectors may enhance their diagnostic accuracy. The survey focused on the healthcare practitioners most likely to initially assess and diagnose symptomatic patients, including doctors of medicine (MDs), doctors of osteopathic medicine, physician assistants (PAs), and nurse practitioners (NPs), as well as specialties including Emergency Medicine, Family Practice, Pediatrics, and Urgent Care.