Cardiac Manifestations of Rocky Mountain Spotted Fever

An increasing incidence of Rocky Mountain spotted fever is being noted across the United States. From 1955 to 1978 80 children with this disease were seen in a children's hospital. Autopsies were performed in six of the nine fatal cases, and cardiac lesions were seen in each. Multifocal myocarditis with petechiae was present in four cases, and in two of them there were areas of myocardial necrosis. In four of the necropsied cases there were electrocardiographic changes and cardiac enlargement on chest roentgenogram. Among survivors five patients manifested at least one cardiac abnormality. ST-T changes were noted in two patients, atrioventricular conduction disturbance in two, and severe left ventricular hypertrophy in one patient. Cardiomegaly was observed in three patients, and one had severe cardiac failure that responded to medical management. Cardiac involvement is frequently present in Rocky Mountain spotted fever, and close observation seems to be warranted.

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Mosquito and Tick-borne Illnesses in the United States. Guidelines for the Recognition and Empiric Treatment of Zoonotic Diseases in the Wilderness.

Infectious Disorders - Drug Targets ◽

10.2174/1871526518666180626123340 ◽

2019 ◽

Vol 19 (3) ◽

pp. 238-257

Author(s):

Suresh Antony

Keyword(s):

United States ◽

Lyme Disease ◽

Spotted Fever ◽

Disease Process ◽

Rocky Mountain ◽

The United States ◽

Health Care Facilities ◽

Diagnostic Tools ◽

Rocky Mountain Spotted Fever ◽

Number Of Patients

Background:In the United States, tick-borne illnesses account for a significant number of patients that have been seen and treated by health care facilities. This in turn, has resulted in a significant morbidity and mortality and economic costs to the country.Methods:The distribution of these illnesses is geographically variable and is related to the climate as well. Many of these illnesses can be diagnosed and treated successfully, if recognized and started on appropriate antimicrobial therapy early in the disease process. Patient with illnesses such as Lyme disease, Wet Nile illness can result in chronic debilitating diseases if not recognized early and treated.Conclusion:This paper covers illnesses such as Lyme disease, West Nile illness, Rocky Mountain Spotted fever, Ehrlichia, Tularemia, typhus, mosquito borne illnesses such as enteroviruses, arboviruses as well as arthropod and rodent borne virus infections as well. It covers the epidemiology, clinical features and diagnostic tools needed to make the diagnosis and treat these patients as well.

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Dermacentor variabilis is the Predominant Dermacentor spp. (Acari: Ixodidae) Feeding on Dogs and Cats Throughout the United States

Journal of Medical Entomology ◽

10.1093/jme/tjab007 ◽

2021 ◽

Author(s):

Kathryn T Duncan ◽

Meriam N Saleh ◽

Kellee D Sundstrom ◽

Susan E Little

Keyword(s):

United States ◽

Spotted Fever ◽

Rocky Mountain ◽

The United States ◽

Dermacentor Variabilis ◽

Western United States ◽

Its2 Region ◽

Rrna Gene ◽

Rocky Mountain Spotted Fever ◽

Dermacentor Albipictus

Abstract Throughout North America, Dermacentor spp. ticks are often found feeding on animals and humans, and are known to transmit pathogens, including the Rocky Mountain spotted fever agent. To better define the identity and distribution of Dermacentor spp. removed from dogs and cats in the United States, ticks submitted from 1,457 dogs (n = 2,924 ticks) and 137 cats (n = 209 ticks) from veterinary practices in 44/50 states from February 2018-January 2020 were identified morphologically (n = 3,133); the identity of ticks from regions where Dermacentor andersoni (Stiles) have been reported, and a subset of ticks from other regions, were confirmed molecularly through amplification and sequencing of the ITS2 region and a 16S rRNA gene fragment. Of the ticks submitted, 99.3% (3,112/3,133) were Dermacentor variabilis (Say), 0.4% (12/3,133) were D. andersoni, and 0.3% (9/3,133) were Dermacentor albipictus (Packard). While translocation of pets prior to tick removal cannot be discounted, the majority (106/122; 87%) of Dermacentor spp. ticks removed from dogs and cats in six Rocky Mountain states (Montana, Idaho, Wyoming, Nevada, Utah, and Colorado) were D. variabilis, suggesting this species may be more widespread in the western United States than is currently recognized, or that D. andersoni, if still common in the region, preferentially feeds on hosts other than dogs and cats. Together, these data support the interpretation that D. variabilis is the predominant Dermacentor species found on pets throughout the United States, a finding that may reflect recent shifts in tick distribution.

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