Patient characteristics, treatment patterns, and outcomes of Rickettsial diseases among a commercially insured population in the United States, 2005-2017.

Rickettsial diseases (RDs) are transmitted to humans by ectoparasites, including ticks and fleas. Symptoms range from mild febrile illness, to severe disease or death. Doxycycline is the treatment of choice for patients of all ages; early treatment based on clinical diagnosis is critical to prevent severe outcomes. We conducted a descriptive analysis using insurance claims data captured by IBM MarketScan® research databases to describe demographics, treatment patterns, and outcomes of patients diagnosed with RDs in the United States during 2005-2017. Overall, 14,830 patients had a RD diagnosis during 2005-2017; 7,517 (50.7%) spotted fever rickettsiosis (SFR), 4,571 ( 30.8%) ehrlichiosis, 1,362 (9.2%) typhus group rickettsiosis (TGR), and 1,193 (8.0%) other rickettsial diseases. Among all patients diagnosed, 53.1% received doxycycline. Prescription rates varied by diagnosis and age; 24.1% of TGR and 61.1% of SFR patients received doxycycline; 23.9% of persons < 8 years received doxycycline, compared with 47.7% for 8-17 years, and 55.4% for ≥ 18 years. RDs are frequently diagnosed in the outpatient population; however, providers prescribed the recommended treatment to about half of patients. Continued education of treatment recommendations is critical to prevent severe outcomes.

Rickettsia sibirica mongolitimonae Infection, Turkey, 2016.

In 2016, Rickettsia sibirica mongolitimonae was diagnosed for a man in Turkey. He had been bitten by a Hyalomma marginatum tick, from which PCR detected rickettsial DNA. Sequence analysis of the DNA identified R. sibirica mongolitimonae. Immunofluorescence assay of patient serum indicated R. conorii, which cross-reacts. PCR is recommended for rickettsiosis diagnoses.

Rickettsia sibirica mongolitimonae Infection, France, 2010-2014.

To further characterize human infections caused by Rickettsia sibirica mongolitimonae, we tested skin biopsy and swab samples and analyzed clinical, epidemiologic, and diagnostic characteristics of patients with a rickettsiosis. The most common (38%) indigenous species was R. sibirica mongolitimonae. Significantly more cases of R. sibirica mongolitimonae infection occurred during spring and summer.

Q Fever, Scrub Typhus, and Rickettsial Diseases in Children, Kenya, 2011-2012.

To increase knowledge of undifferentiated fevers in Kenya, we tested paired serum samples from febrile children in western Kenya for antibodies against pathogens increasingly recognized to cause febrile illness in Africa. Of patients assessed, 8.9%, 22.4%, 1.1%, and 3.6% had enhanced seroreactivity to Coxiella burnetii, spotted fever group rickettsiae, typhus group rickettsiae, and scrub typhus group orientiae, respectively.

CONTRIBUTIONS TO RICKETTSIOSES RESEARCH IN COLOMBIA (1917-1943), LUIS B. PATIÑO CAMARGO.

Colombian physician Luis Benigno Patiño Camargo was one of the pioneers in the study of rickettsioses in South America, demonstrating for the first time in Colombia the presence of Rickettsia rickettsii as the etiological agent of a highly deadly exanthematic febrile syndrome in the 1930s. However, Patiño-Camargo performed other investigations from 1917-1943, which represent the first descriptions and scientific evidence of the presence of R. prowazekii and R. typhi in Colombia. Almost 60 years after the latest research conducted by Dr. Patiño-Camargo, rickettsioses were again a matter of interest and research. In the last decade over 20 research studies have been published, showing new endemic areas for R. rickettsii, as well as the description of new rickettsial species in Colombia.

[Nature-focal rickettsioses in Mongolia. Two decades of Russian-Mongolian scientific collaboration].

The results of many years' studies of nature-focal rickettsioses in Mongolia in collaboration of Soviet (Russian) and Mongolian specialists under leadership of I. V. Tarasevich are represented. Presence of contacts of population, domestic and wild animals with Coxiella burnetii and Rickettsia sibirica on the territory of Mongolia was established. The map of spread of ticks corresponding to their epidemiological significance was developed. Methodological documents for prevention of nature-focal rickettsioses in Mongolia were developed for organs of healthcare and veterinary medicine. Corpuscular inactivated vaccine against Q-fever from immunogenic strains "Dermacentor-Mongol 1". "XY -1958" was prepared.

Rickettsiosis en el Uruguay: descripción de una nueva forma clínica de la enfermedad / Rickettsiosis in Uruguay: description of a new clinical form of the disease

Presenta la descripción de una nueva forma clínica de la enfermedad reckettsiosis. Las rickettsias son organismos coco-bacilares, Gran negativos, de 2-3 micras de diámetro, intracelulares, incapaces de desarrollarse en ausencia de células vivas. [AU]

History of U.S. military contributions to the study of rickettsial diseases.

Rickettsial diseases have affected the military throughout history. Efforts such as those of the Joint U.S. Typhus Commission near the beginning of World War II and of military researchers since have reduced the impact of these diseases on U.S. and Allied forces. Despite the postwar development of effective antibiotic therapies, the newly emerging antibiotic-resistant scrub typhus rickettsial strains of the Asian Pacific region mandate continued research and surveillance. Similarly, tick-infested training areas in the United States and similar exposure abroad render the spotted fevers and the ehrlichioses problematic to deployed troops. The military continues to work on countermeasures to control the arthropod vectors, as well as actively participating in the development of rapid accurate diagnostic tests, vaccines, and improved surveillance methods. Several rickettsial diseases, including epidemic typhus, scrub typhus, the ehrlichioses, and the spotted fevers, are reviewed, with emphasis on the military historical significance and contributions.

Rickettsia parkeri as a paradigm for multiple causes of tick-borne spotted fever in the western hemisphere.

Among the many contributions made to rickettsiology by entomologist and rickettsiologist Ralph R. Parker was his discovery in 1937 of a novel rickettsia isolated from the Gulf Coast tick, Amblyomma maculatum. This bacterium was subsequently characterized as a unique rickettsial species in 1965 and named Rickettsia parkeri in honor of its discoverer. During the next several decades R. parkeri was generally considered as one of several "nonpathogenic" spotted fever group (SFG) rickettsiae that resided in ticks of the United States. The identification of novel rickettsioses on other continents during the last two decades of the twentieth century provided important evidence of the frequent coexistence of multiple and unique tick-borne SFG rickettsiae sharing common geographic regions. Surprisingly, this paradigm, which was repeatedly demonstrated in Europe, Africa, and Australia during the last 10 years, had no confirmed correlate in the United States until 2002, when R. parkeri was isolated from a patient from the state of Virginia. Several pieces of epidemiologic, laboratory, and clinical evidence are compelling enough to suggest that this infection has occurred in other U.S. patients who reside within the range of the Gulf Coast tick. Just as important are new data indicating relatively high infection rates of A. maculatum ticks with R. parkeri, documenting the occurrence of R. parkeri in Amblyomma triste ticks from Uruguay, and providing evidence that other Amblyomma species might serve as efficient vectors of R. parkeri. The recognition of R. parkeri as a cause of disease in humans will hopefully encourage a closer examination for specific etiologies of tick-borne spotted fever rickettsioses in the United States and other countries of the Western Hemisphere.

Bullis fever: a vanished infection of unknown etiology.

Camp Bullis, Texas, is an active training facility for the U.S. Army and Air Force with a storied history dating back to the late 19th century. In the early 1940s, an epidemic of a seasonal tick-borne rickettsial-like illness occurred at Camp Bullis; the last case was reported in 1947. To date, the etiology of this disease has remained elusive. In an attempt to retrospectively identify the causal pathogen, we surveyed Camp Bullis for the presumed tick vector with intent to screen molecularly for Rickettsia and Ehrlichia. However, no ticks were recovered from primary dragging attempts in the spring or from harvested deer in the fall. Moreover, pathologic and microbiologic materials obtained during the epidemic are no longer extant, making them unavailable for analysis. In this study, we review potential circumstances that impact emerging and, in this case, vanishing infections. The etiology of Bullis fever will probably remain undetermined, and this once-emerging infection may have vanished into history. However, given Camp Bullis' status as an active medical training site, awareness of and surveillance for the disease should continue.