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Crimean-Congo hemorrhagic fever virus can cause lethal disease in humans yet there are no approved medical countermeasures. Viral glycoprotein GP38, unique to Nairoviridae , is a target of protective antibodies, but extensive mapping of the human antibody response to GP38 has not been previously performed. Here, we isolated 188 GP38-specific antibodies from human survivors of infection. Competition experiments showed that these antibodies bind across five distinct antigenic sites, encompassing eleven overlapping regions. Additionally, we reveal structures of GP38 bound with nine of these antibodies targeting different antigenic sites. Although GP38-specific antibodies were non-neutralizing, several antibodies were found to have protection equal to or better than murine antibody 13G8 in two highly stringent rodent models of infection. Together, these data expand our understanding regarding this important viral protein and inform the development of broadly effective CCHFV antibody therapeutics., Competing Interests: DECLARATION OF INTERESTS N.T.P., E.C., and J.L. are employees and shareholders of Adimab, LLC. D.P.M., L.M.W., O.S.S., V.H., and M.D. are shareholders of Adimab.

Neuroborreliosis initially misdiagnosed as Lyme disease was discovered to be caused by the relapsing fever spirochete Borrelia turicatae., Tickborne relapsing fever spirochetes are an overlooked cause of disease around the globe. We report a case of tickborne relapsing fever in a patient in Texas, USA, who had a single febrile episode and gastrointestinal and neurologic symptoms. Immunoblot analysis using recombinant Borrelia immunogenic protein A implicated Borrelia turicatae as the causative agent.

Crimean-Congo hemorrhagic fever (CCHF), Q fever, and Lyme disease are endemic to southern Kazakhstan, but population-based serosurveys are lacking. We assessed risk factors and seroprevalence of these zoonoses and conducted surveys for CCHF-related knowledge, attitudes, and practices in the Zhambyl region of Kazakhstan. Weighted seroprevalence for CCHF among all participants was 1.2%, increasing to 3.4% in villages with a known history of CCHF circulation. Weighted seroprevalence was 2.4% for Lyme disease and 1.3% for Q fever. We found evidence of CCHF virus circulation in areas not known to harbor the virus. We noted that activities that put persons at high risk for zoonotic or tickborne disease also were risk factors for seropositivity. However, recognition of the role of livestock in disease transmission and use of personal protective equipment when performing high-risk activities were low among participants.

An update of the 2006 American College of Veterinary Internal Medicine (ACVIM) Small Animal Consensus Statement on Lyme Disease in Dogs: Diagnosis, Treatment, and Prevention was presented at the 2016 ACVIM Forum in Denver, CO, followed by panel and audience discussion and a drafted consensus statement distributed online to diplomates for comment. The updated consensus statement is presented below. The consensus statement aims to provide guidance on the diagnosis, treatment, and prevention of Lyme borreliosis in dogs and cats.

We conducted an investigation of Borrelia miyamotoi infections in humans and ticks in northeastern China. Of 984 patients reporting recent tick bites, 14 (1.4%) were found to be infected with B. miyamotoi by PCR and genomic sequencing. The 14 patients had nonspecific febrile manifestations, including fever, headache, anorexia, asthenia, and arthralgia. Rash, eschar, and regional lymphadenopathy were each observed in 1 patient. Four (28.6%) patients were hospitalized because of severe disease. B. miyamotoi was detected in 3.0% (19/627) of Ixodes persulcatus, 1 (2.8%) of 36 Haemaphysalis concinna, and none of 29 Dermacentor silvarum ticks. Phylogenetic analyses based on sequences of a nearly entire 16s rRNA gene, a partial flagellin gene, and the glycerophosphodiester phosphodiesterase gene revealed that B. miyamotoi identified in patients and ticks were clustered in the group of the Siberian type. These findings indicate that B. miyamotoi is endemic in northeastern China and its public health significance deserves further investigation.

Powassan virus (POWV) lineage II is an emerging tickborne flavivirus with an unknown seroprevalence in humans. In a Lyme disease-endemic area, we examined the seroreactivity to POWV in 2 patient cohorts and described the clinical features of the POWV-seroreactive patients. POWV disease might be less neuroinvasive than previously thought.

In most locations except for Russia, tick-borne encephalitis is mainly caused by the European virus subtype. In 2015, fatal infections caused by European and Siberian tick-borne encephalitis virus subtypes in the same Ixodes ricinus tick focus in Finland raised concern over further spread of the Siberian subtype among widespread tick species.

To describe the presence and distribution of tickborne bacteria and their vectors in Texas, USA, we screened ticks collected from humans during 2008–2014 for Rickettsia, Borrelia, and Ehrlichia spp. Thirteen tick species were identified, and 23% of ticks carried bacterial DNA from at least 1 of the 3 genera tested.

Candidatus Neoehrlichia is increasingly being recognized worldwide as a tickborne pathogen. We report a case of symptomatic neoehrlichiosis in an immunocompetent Austria resident who had recently returned from travel in Tanzania. The use of Anaplasmataceae-specific PCR to determine the duration of antimicrobial therapy seems reasonable to avert recrudescence.

We investigated the infection rate for severe fever with thrombocytopenia syndrome virus (SFTSV) among ticks collected from humans during May–October 2013 in South Korea. Haemaphysalis longicornis ticks have been considered the SFTSV vector. However, we detected the virus in H. longicornis, Amblyomma testudinarium, and Ixodes nipponensis ticks, indicating additional potential SFTSV vectors.

Lyme disease occurs in specific geographic regions of the United States. We present a method for defining high-risk counties based on observed versus expected number of reported human Lyme disease cases. Applying this method to successive periods shows substantial geographic expansion of counties at high risk for Lyme disease.

LETTERS and the EMIDA ERA-NET and INIA grant APHAEA. Miguel Delibes-Mateos, Catarina Ferreira, Francisco Carro, Marco A. Escudero, and Christian Gortazar Author affiliations: Instituto de Investig- acion en Recursos Cinegeticos, a collab- orative agency of the Consejo Superior de Investigaciones Cientificas, Universidad de Castilla-La Mancha, and Junta de Co- munidades de Castilla-La Mancha, Ciudad Real, Spain (M. Delibes-Mateos, C. Gor- tazar); Trent University, Peterborough, Ontario, Canada (C. Ferreira); Estacion Biologica de Donana, Seville, Spain (F. Carro); and Ebronatura, Zaragoza, Spain (M.A. Escudero) DOI: http://dx.doi.org/10.3201/eid2012.140517 References 1. Delibes-Mateos M, Ferreras P, Villafuerte R. European rabbit population trends and associated factors: a review of the situation in the Iberian Peninsula. Mammal Review. 2009;39:124–40. http:// dx.doi.org/10.1111/j.1365-2907.2009. 00140.x 2. Calvete C. Modeling the effect of population dynamics on the impact of rabbit hemorrhagic disease. Conserv Biol. 2006;20:1232–41. http://dx.doi. org/10.1111/j.1523-1739.2006.00371.x 3. Le Gall-Recule G, Zwingelstein F, Boucher S, Le NB, Plassiart G, Portejoie Y, et al. Detection of a new variant of rab- bit haemorrhagic disease virus in France. Vet Rec. 2011;168:137–8. http://dx.doi. org/10.1136/vr.d697 4. Dalton KP, Nicieza I, Balseiro A, Muguerza MA, Rosell JM, Casais R, et al. Variant rabbit hemorrhagic disease virus in young rabbits, Spain. Emerg Infect Dis. 2012;18:2009–12. http://dx. doi.org/10.3201/eid1812.120341 5. Calvete C, Calvo JH, Sarto P. Deteccion de una nueva variante del virus de la en- fermedad hemorragica en conejos silves- tres en Espana. In: Abstracts of the 37th symposium de cunicultura de ASESCU, 2012 May 24–25. Barbastro (Spain): Aso- ciacion Espanola de Cunicultura; 2012. 6. Dalton KP, Nicieza I, Abrantes J, Esteves PJ, Parra F. Spread of new variant of RHDV in domestic rabbits on the Iberian Peninsula. Vet Microbiol. 2014;169:67–73. http:// dx.doi.org/10.1016/j.vetmic.2013.12.015 7. Abrantes J, Lopes AM, Dalton KP, Melo P, Correia JJ, Ramada M, et al. New vari- ant of rabbit hemorrhagic disease vi- rus, Portugal, 2012–2013. Emerg Infect Dis. 2013;19:1900–2. http://dx.doi.org/ 10.3201/eid1911.130908 8. Williams D, Acevedo P, Gortazar C, Escudero MA, Labarta JL, Marco MA, et al. Hunting for answers: rabbit (Oryc- tolagus cuniculus) population trends in northeastern Spain. European Journal of Wildlife Research. 2007;53:19–28. http://dx.doi.org/10.1007/s10344-006- 9. Delibes-Mateos M, Delibes M, Ferreras P, Villafuerte R. Key role of European rab- bits in the conservation of the western Mediterranean Basin hotspot. Conserv Biol. 2008;22:1106–17. http://dx.doi.org/ 10.1111/j.1523-1739.2008.00993.x 10. Garrote G. Repoblaciones del conejo de monte en gran escala para la conservacion del lince Iberico. In: Abstracts of the First International Wild Rabbit Seminar, 2013 Oct. 23–25. Beja (Portugal): Associacao IBERLINX, Instituto da Conservacao da Naturaleza e das Florestas, and Junta de Andalucia; 2013, p. 6. Address for correspondence: Miguel Delibes- Mateos. Instituto de Investgacion en Recursos Cinegeticos, IREC-CSIC-UCLM-JCCM, Ronda de Toledo s/n 13071 Ciudad Real, Spain; email: mdelibesmateos@gmail.com Molecular Characterization of Borrelia burgdorferi from Case of Autochthonous Lyme Arthritis To the Editor: The first Lyme borreliosis (LB) case reported to be acquired in California occurred in 1978 (1). During the past 10 years, 744 confirmed LB cases were reported in California; 419 (56.2%) were likely acquired in-state. The highest inci- dence of this disease occurs in north- ern coastal California, in locations such as Santa Cruz County (2), where habitat supports yearlong activity of the tick vector Ixodes pacificus (3,4). Existing data describe the genet- ic diversity of the LB agent Borrelia burgdorferi among ticks in Californa (5,6), but few instances of direct de- tection and genetic characterization of B. burgdorferi sensu stricto in samples from humans are documented in Cali- fornia. B. burgdorferi has been iso- lated from skin biopsy samples of 3 patients in California in whom LB was diagnosed (1). Seinost et al. genotyped strains isolated in the United States, including 7 isolates identified in Cali- fornia from skin, blood, or cerebrospi- nal fluid, but no documented exposure information was available (7). Girard et al. genotyped B. burgdorferi in 10- to 12-year-old stored serum samples collected from 22 northern California residents, some of whom were as- ymptomatic at time of collection. Of 22 PCR-positive specimens, 21 had the single laboratory type strain B31 genotype (3). A 12-year-old resident of Santa Cruz County, California, came to the emergency department of Dominican Hospital in September 2012 with a swollen, painful right knee and mildly painful right hip. The patient’s family reported that LB had been diagnosed by a local physician. Illness onset was in May 2010; symptoms consisted of recurrent knee swelling and pain last- ing several days every 4–5 months and positive serologic test results for B. burdorferi (not available). The pa- tient had not traveled outside of Cali- fornia during the preceding 6 years. In May 2011, an IgG Western blot of the patient’s serum that was processed at a commercial laboratory showed immunoreactive bands of 18, 23, 28, 30, 39, 41, 45, 58, 66, and 93 kDa. In both 2010 and 2011, the patient’s fam- ily had chosen to give the patient un- specified herbal treatments instead of antibacterial drugs. On physical examination in the emergency department, the patient’s right knee was swollen; knee flexion Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 20, No. 12, December 2014

TOC summary: Infection was associated with tick bites and contact with farm animals., Alkhurma virus is a flavivirus, discovered in 1994 in a person who died of hemorrhagic fever after slaughtering a sheep from the city of Alkhurma, Saudi Arabia. Since then, several cases of Alkhurma hemorrhagic fever (ALKHF), with fatality rates up to 25%, have been documented. From January 1, 2006, through April 1, 2009, active disease surveillance and serologic testing of household contacts identified ALKHF in 28 persons in Najran, Saudi Arabia. For epidemiologic comparison, serologic testing of household and neighborhood controls identified 65 serologically negative persons. Among ALKHF patients, 11 were hospitalized and 17 had subclinical infection. Univariate analysis indicated that the following were associated with Alkhurma virus infection: contact with domestic animals, feeding and slaughtering animals, handling raw meat products, drinking unpasteurized milk, and being bitten by a tick. After multivariate modeling, the following associations remained significant: animal contact, neighboring farms, and tick bites.

Surveillance for this emerging disease should be expanded to the outpatient setting., In South Korea, nationwide surveillance for severe fever with thrombocytopenia syndrome (SFTS) began during 2013. Among 301 surveillance cases, 35 hospitalized case-patients in 25 areas were confirmed by using virologic testing, and 16 (46%) case-patients subsequently died. The SFTS cases occurred during May–November and peaked during June (9 cases, 26%). The incidence of SFTS was higher in the southern regions of South Korea. Age and neurologic symptoms, including decreased level of consciousness and slurred speech, were heavily associated with death; neurologic symptoms during the first week after disease onset were also associated with death. Although melena was common among patients who died, no other hemorrhagic manifestations were substantively more common among those who died. No effective treatments, including ribavirin, were identified. Expansion of SFTS surveillance to include the outpatient sector and development of an antibody test would enhance completeness of SFTS detection in South Korea.

© 2015 Barbour et al. Background: The reservoirs for the Lyme disease agent, Borrelia burgdorferi, are dominated by several different small to medium sized mammals in eastern North America. Findings: To experimentally assess the competence of different mammalian species to transmit this pathogen to ticks, we carried out quantitative species-specific PCR of individual nymphal Ixodes scapularis ticks, which had been collected as replete larvae from animals captured at a field site in eastern Connecticut and then allowed to molt in the laboratory. The mammals, in order of increasing body mass, were the white-footed mouse, pine vole, eastern chipmunk, gray squirrel, Virginia opossum, striped skunk, and common raccoon. The prevalence of infection in the nymphs and the counts of spirochetes in infected ticks allometrically scaled with body mass with exponents of -0.28 and -0.29, respectively. By species, the captured animals from the site differed significantly in the mean counts of spirochetes in the ticks recovered from them, but these associations could not be distinguished from an effect of body size per se. Conclusions: These empirical findings as well as inferences from modeling suggest that small mammals on the basis of their sizes are more competent as reservoirs of B. burgdorferi in this environment than medium-to large-sized mammals.

© 2015 Elsevier GmbH. Peromyscus leucopus, the white-footed mouse, is one of the more abundant mammals of North America and is a major reservoir host for at least five tickborne diseases of humans, including Lyme disease and a newly-recognized form of relapsing fever. In comparison to Mus musculus, which is not a natural reservoir for any of these infections, there has been little research on experimental infections in P. leucopus. With the aim of further characterizing the diversity of phenotypes of host responses, we studied a selection of quantitative traits in colony-bred and -reared outbred P. leucopus adults that were uninfected, infected with the relapsing fever agent Borrelia hermsii alone, or infected after immunization with Lyme disease vaccine antigen OspA and keyhole limpet hemocyanin (KLH). The methods included measurements of organ weights, hematocrits, and bleeding times, quantitative PCR for bacterial burdens, and enzyme immunoassays for serum antibodies against both the immunization proteins and cellular antigens of the infecting organism. The results included the following: (i) uninfected animals displayed wide variation in relative sizes of their spleens and in their bleeding times. (ii) In an experiment with matched littermates, no differences were observed between females and males at 7 days of infection in bacterial burdens in blood and spleen, relative spleen size, or antibody responses to the B. hermsii specific-antigen, FbpC. (iii) In studies of larger groups of males or females, the wide variations between bacterial burdens and in relative spleen sizes between individuals was confirmed. (iv) In these separate groups of males and females, all animals showed moderate-to-high levels of antibodies to KLH but wide variation in antibody levels to OspA and to FbpC. The study demonstrated the diversity of host responses to infection and immunization in this species and identified quantitative traits that may be suitable for forward genetics approaches to reservoir-pathogen interactions.

© 2015 Elsevier GmbH. Peromyscus leucopus, the white-footed mouse, is one of the more abundant mammals of North America and is a major reservoir host for at least five tickborne diseases of humans, including Lyme disease and a newly-recognized form of relapsing fever. In comparison to Mus musculus, which is not a natural reservoir for any of these infections, there has been little research on experimental infections in P. leucopus. With the aim of further characterizing the diversity of phenotypes of host responses, we studied a selection of quantitative traits in colony-bred and -reared outbred P. leucopus adults that were uninfected, infected with the relapsing fever agent Borrelia hermsii alone, or infected after immunization with Lyme disease vaccine antigen OspA and keyhole limpet hemocyanin (KLH). The methods included measurements of organ weights, hematocrits, and bleeding times, quantitative PCR for bacterial burdens, and enzyme immunoassays for serum antibodies against both the immunization proteins and cellular antigens of the infecting organism. The results included the following: (i) uninfected animals displayed wide variation in relative sizes of their spleens and in their bleeding times. (ii) In an experiment with matched littermates, no differences were observed between females and males at 7 days of infection in bacterial burdens in blood and spleen, relative spleen size, or antibody responses to the B. hermsii specific-antigen, FbpC. (iii) In studies of larger groups of males or females, the wide variations between bacterial burdens and in relative spleen sizes between individuals was confirmed. (iv) In these separate groups of males and females, all animals showed moderate-to-high levels of antibodies to KLH but wide variation in antibody levels to OspA and to FbpC. The study demonstrated the diversity of host responses to infection and immunization in this species and identified quantitative traits that may be suitable for forward genetics approaches to reservoir-pathogen interactions.

To the Editor: Crimean-Congo hemorrhagic fever (CCHF) is a tickborne zoonotic disease caused by a member of the virus family Bunyaviridae, genus Nairovirus. This virus (CCHFV) has caused illness throughout Asia, Europe, Africa, and the Middle East (1). CCHFVs are clustered among 7 genotypes (Asia-1, Asia-2, Euro-1, Euro-2, Africa-1, Africa-2, and Africa-3) on the basis of genetic variation in the small segment (2). These genotypes are well conserved among their regions of origin; however, >1 genotype is prevalent in many countries (2). In Pakistan, the first CCHF case was reported in 1976; multiple sporadic cases and outbreaks have occurred in subsequent years (3). To determine which genotypes were present in Pakistan, we performed molecular analysis of archived serum samples collected during 2008 in Fatima Jinnah General and Chest Hospital, Quetta, Baluchistan, in southwestern of Pakistan. Because of limited diagnostic facilities for CCHFV in this country, samples collected during 1976–2002 were occasionally sent to laboratories in countries such as South Africa and the United States, where genetic analysis showed that all viruses tested from that location belonged to the Asia-1 genotype (4). Data beyond this period are not available; however, because of improved molecular diagnostic facilities at the Department of Virology, National Institute of Health, Pakistan, blood samples collected from patients with suspected cases attending in-country hospitals are now examined by the institute for confirmation. Our findings substantiate the presence of Asia-1 and Asia-2 genotypes in Baluchistan. Thirteen IgM-positive samples collected during 2008 and stored at –70°C were available for study. The samples were processed for amplification of 260 bp of the small segment by using reverse transcription PCR with a previously described protocol (5). The mean age of patients with serology-confirmed CCHF was 31.3 (range 18–40) years; male-to-female IgM positivity ratio was 1:2. Common symptoms were fever, headache, and nosebleeds. Platelet counts ranged from 16,000 to 43,000/μL of blood. Of the 13 samples, viral RNA was detected in 2 (CCHF-65–2008PAK and CCHF-43–2008PAK); the amplicons were subjected to bidirectional sequencing by using the BigDye Terminator v3.1 cycle sequencing kit (Applied BioSystems, Foster City, CA, USA). Sequences were analyzed with Sequencher (GeneCodes Corp., Ann Arbor, MI, USA) and MEGA v4.0 (http://megasoftware.net/). The 2 viruses were phylogenetically clustered into Asia-1 and Asia-2 genotypes, with 7% nucleotide divergence, although both samples were collected during September–October, 2008. The closest nucleotide identity (99%–100%) for CCHF-65–2008PAK was found with the previously reported Asia-1 strains from Pakistan, Afghanistan, and Iran; CCHF-43–2008PAK had 96%–97% similarity to viruses from Dubai and Tajikistan (Figure). The sequences reported from United Arab Emirates, Pakistan, Afghanistan, Iran, and Iraq belong to the Asia-1 genotype; the Asia-2 genotype sequences were mostly from China and Central Asian countries such as Uzbekistan, Tajikistan, and Kazakhstan (6). All viruses detected intermittently in Pakistan during 1976–2002 were of the Asia-1 genotype (4). However, the analysis of the 2 samples reported here enhances our knowledge of CCHFV genetic diversity in Pakistan. Figure Phylogenetic analysis of partial small gene fragment (220 bp) obtained from Crimean-Congo hemorrhagic fever virus strains analyzed in this study (black circles). Reference strains belong to different genogroups as retrieved from GenBank. Diamonds indicate ... The closest phylogenetic positioning of CCHF-43–2008PAK with Asia-2 strain Dubai-616 (GenBank accession no. {"type":"entrez-nucleotide","attrs":{"text":"JN108025","term_id":"354990643","term_text":"JN108025"}}JN108025) indicates that the probable route of CCHFV transmission was through animal trade between the United Arab Emirates and Pakistan. This finding supports the proposition that animals imported from Pakistan were the probable source of a 1979 outbreak in the United Arab Emirates (7). However, we cannot determine the direct source of the Asia-2 genotype in Pakistan, nor confirm the transmission link between the 2 countries. We attribute this to a lack of consistent, contemporary viral genetic information of CCHFV strains in Pakistan and the United Arab Emirates. This lack of data necessitates intensive surveillance and epidemiologic investigations in animal and human populations because geographic factors alone do not provide comprehensive information about the diversity of CCHFV strains circulating in Asia (6). The presence of geographically distant, but genetically similar, strains suggests that the viruses are dispersed either through animal trade or migratory birds (8). No clear evidence of CCHFV infection in migratory birds has been found, but they may play a major role in translocation of infected ticks to distant areas (9). Birds are known to be parasitized by these vectors of CCHFV in eastern Europe and Asia and disseminate the virus by transporting infected immature ticks between continents (4). It is therefore highly advisable to develop an active surveillance system with appropriate laboratory facilities to conduct the seroepidemiologic surveys and screening of household animals and vectors for CCHFV to rule out potential risks. Our study was limited by a low number of samples, resulting in availability of only a short fragment of the small gene for analysis. However, similar partial small gene sequencing has been used in previous studies (2) and has supported the classification of CCHFV strains correctly into 7 genotypes. In conclusion, because tick control is not feasible, surveillance activities and laboratory facilities should be improved. Health care workers should also be aware of proper patient management and standard prophylactic and preventive measures, particularly in areas where CCHFV is endemic, such as Baluchistan, where many deaths associated with nosocomial transmission have been reported (10).

To the Editor: Tickborne relapsing fever (TBRF) is caused by several Borrelia species and transmitted by argasid soft ticks of the genus Ornithodoros. The disease is endemic to many parts of the world, especially Africa (B. duttonii and B. crocidurae most prevalent), and the Mediterranean basin (B. hispanica most prevalent). In Eurasia, TBRF is mainly caused by B. persica (1–3). We report a patient who returned to France with B. persica infection after visiting Uzbekistan and Tajikistan. In September 2008, a 32-year-old man sought care at the Saint Louis Hospital in Paris, France, for a fifth relapsing episode of fever. Three weeks earlier (July 31–August 18), he had trekked through Uzbekistan and Tajikistan and spent 7 nights in a tent in Uzbekistan. The day before his return to France, he had fever (39.5°C) that lasted 5 days without other symptoms. After a 4-day interval, fever recurred for 1 day, then relapsed 3 other times (every 2 days with fever for 12 hours). Laboratory investigations performed earlier by his general physician on August 19 and 20 showed lymphopenia (0.76 × 109 cells/L and 0.44 × 109 cells/L), thrombocytopenia (94 ×109 cells/L and 80 ×109 cells/L), and C-reactive protein level 300 mg/L (reference level

As opposed to unfed ticks, transmission of R. rickettsii occurred in, Rocky Mountain spotted fever is endemic to the São Paulo metropolitan area, Brazil, where the etiologic agent, Rickettsia rickettsii, is transmitted to humans by adult Amblyomma aureolatum ticks. We determined the minimal feeding period required by A. aureolatum nymphs and adults to transmit R. rickettsii to guinea pigs. Unfed nymphs and unfed adult ticks had to be attached to the host for >10 hours to transmit R. rickettsii. In contrast, fed ticks needed a minimum of 10 minutes of attachment to transmit R. rickettsii to hosts. Most confirmed infections of Rocky Mountain spotted fever in humans in the São Paulo metropolitan area have been associated with contact with domestic dogs, the main host of A. aureolatum adult ticks. The typical expectation that transmission of tickborne bacteria to humans as well as to dogs requires ≥2 hours of tick attachment may discourage persons from immediately removing them and result in transmission of this lethal bacterium.

Myocarditis after Treatment for Ehrlichiosis, The manifestations of human monocytic ehrlichiosis range from a mild febrile syndrome to a severe multisystem illness. Myocardial involvement is uncommon. We report a woman, 78 years of age, who was treated with trimethoprim/sulfamethoxazole after a tick bite, in whom myocarditis was subsequently diagnosed. She recovered completely after doxycycline therapy.