Diseases Transmitted by the Black-Legged Ticks in the United States: A Comprehensive Review of the Literature

Abstract

The black-legged tick is endemic to the midwestern, northeastern, western, south-eastern, and southern regions of the United States. There has been an increased burden of black-legged ticks in humans in recent years. COVID-19 pandemic has further heightened this burden. We thereby reviewed the literature to discuss the seasonality, infections, and clinical spectrum of diseases transmitted by the black-legged ticks. We also discuss the reported delay in the diagnosis of these diseases during the pandemic situation, the alpha-gal syndrome, the importance of prompt diagnosis, and early medical intervention with an aim to increase awareness of the black-legged tick-borne diseases.

<em>Ixodes scapularis</em> Calreticulin Binds Complement Proteins but Does Not Protect <em>Borrelia burgdorferi </em>from Complement Killing

“…The black legged tick, Ixodes scapularis, is a 3-host tick blood feeding ectoparasite that completes its life cycle (larvae to nymph to adult) over 2 years. This tick is considered endemic to several parts of USA including Midwest, Northeast, West, Southeast, and Southern USA and its distribution is dependent on the various ecological factors such as climates, vegetation, landscape and availability of host [1,2]. I. scapularis, which transmits 7 of 16 human tick borne disease (TBD) agents in the USA [2] including causative agents of anaplasmosis (Anaplasma phagocytophilum), babesiosis (Babesia microti), ehrlichiosis (Ehrlichia chaffeensis), hard Tick Relapsing Fever (Borrelia miyamotoi), Powassan encephalitis virus [3][4][5], is famously known for transmission of causative agents of Lyme disease (LD): Borrelia burgdorferi [6] and the recently described B. mayonii [7][8][9].…”

Tick Saliva and Salivary Glands: What Do We Know So Far on Their Role in Arthropod Blood Feeding and Pathogen Transmission

“…Ticks are blood-feeding arthropods that transmits various bacterial, viral and protozoan pathogens to humans and animals ( Azad, 2007 ; Wikel, 2013 ; Neelakanta and Sultana, 2015 ; Schneider et al., 2021 ; Sosa et al., 2021 ). In nature, the successful existence of ticks could be reasoned due to its ability to feed on various animals ( Anderson, 1989 ; Richter et al., 2000 ; Embers et al., 2013 ; Linske et al., 2018 ; Banovic et al., 2021 ; Sidge et al., 2021 ).…”