Rickettsioses share common clinical manifestations, such as fever, malaise, exanthema, the presence or absence of an inoculation eschar, and lymphadenopathy. Some of these manifestations can be suggestive of certain species of Rickettsia infection. Nevertheless none of these manifestations are pathognomonic, and direct diagnostic methods to confirm the involved species are always required. A syndrome is a set of signs and symptoms that characterizes a disease with many etiologies or causes. This situation is applicable to rickettsioses, where different species can cause similar clinical presentations. We propose a syndromic classification for these diseases: exanthematic rickettsiosis syndrome with a low probability of inoculation eschar and rickettsiosis syndrome with a probability of inoculation eschar and their variants. In doing so, we take into account the clinical manifestations, the geographic origin, and the possible vector involved, in order to provide a guide for physicians of the most probable etiological agent.

Highlights Colombia as an endemic country for Dengue, Chikungunya, and Zika virus. Co-epidemics of SARS-CoV-2 with other etiologies is a matter for concern. Serological cross-reactivity in acute Zika infection using a SARS-CoV-2 ELISA test.

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This study discusses a historical patient series and is designed to describe clinical and epidemiological characteristics of human sporotrichosis in the state of Espírito Santo, Brazil. Data were derived from patients treated at the Infectious Diseases service of Cassiano Antônio Moraes University Hospital in Vitória, the state capital, from July 1982 to June 2012. A total of 171 patients were diagnosed with sporotrichosis, mostly men (80.7%) with a median age of 33 years and 5 months. We can presume an approximate average incidence rate of 4.9 cases per 100,000 inhabitants during the studied period. All the patients were involved in occupational or leisure activities with direct contact with soil or plants. Most cases were recorded in the mountainous region of the state during the hot and rainy periods. The average time elapsed from lesion progression to diagnosis was 3 months, with the lymphocutaneous form being the most common (70.2%), followed by the fixed cutaneous form (28.6%). Diagnosis was confirmed in 93.6% of the cases by culturing Sporothrix spp. in Sabouraud dextrose agar, and from the clinical features in the remaining cases. Aspiration of cutaneous nodule secretions was the best method for the collection of clinical specimens for disease diagnosis. A 25% saturated solution of potassium iodide (SSKI) was provided to almost all patients (98.8%), with therapeutic success. In conclusion, in this retrospective study in the state of Espírito Santo, we found that sporotrichosis affects primarily the ³ 10-year-old population, and the most common presentation is the lymphocutaneous form affecting the lower and upper limbs, and the infection appeared to be acquired predominantly through occupational activities. Treatment with SSKI was safe and effective.

Rickettsia typhi and R. felis are the etiological agents of murine typhus and flea-borne spotted fever, respectively. Both are emerging acute febrile zoonotic diseases for which fleas are vectors; they also have similar clinical characteristics and global distribution. In 2005, we identified the circulation of murine typhus in 6 towns within the mountainous coffee-growing area north of Caldas, Colombia. We now report the specific seroprevalence against R. typhi and R. felis, and associated risk factors in 7 towns of this province. The combined seroprevalence against the 2 flea-borne rickettsioses is the highest yet reported in the literature: 71.7% (17.8% for R. felis, 25.2% for R. typhi, and 28.7% for both). We also report a prospective analysis of 26 patients with a febrile illness compatible with rickettsioses, including murine typhus; 9 of these patients had a rickettsiosis. This supports our sero-epidemiological results and highlights the diagnostic complexity of febrile syndromes in this region.

Introdução: A febre maculosa (FM) é uma doença infecciosa, aguda, transmitida por carrapatos, e de gravidade variável. No Brasil, recentemente, tem sido descrita uma nova FM causada por Rickettsia parkeri, cujo perfil clínico, epidemiológico e laboratorial é diferente do perfil da FM causada por Rickettsia rickettsii. Metodologia: trata-se de uma revisão narrativa cujo objetivo é caracterizar a febre maculosa causada por Rickettsia parkeri no Brasil, discutindo as condutas de vigilância epidemiológica, diagnóstico e tratamento. Resultados: A febre maculosa por Rickettsia parkeri no Brasil é produzida, principalmente, pela R. parkeri cepa Mata Atlântica, presente no bioma Mata Atlântica das regiões Sul, Sudeste e Nordeste, onde o carrapato Amblyomma ovale figura como o principal vetor da doença. A suspeição clínica e epidemiológica deve considerar os pacientes que apresentam doença febril e presença da escara de inoculação, associadas à visita em área de mata e ou contatos com carrapatos. A coleta de material biológico (que inclua a escara de inoculação) deve ser realizada, oportunamente, para a caracterização do agente etiológico. O tratamento com antibioticoterapia deve ser iniciado já no início dos sintomas, e todos os casos devem ser notificados ao Ministério da Saúde e investigados imediatamente. A caracterização do ambiente de infecção é importante para melhor compreensão da ecoepidemiologia da doença e desencadeamento de medidas de prevenção e controle. Conclusão: Estabelecemos um protocolo para os profissionais de saúde com as condutas de vigilância epidemiológica, diagnóstico e tratamento para febre maculosa causada por Rickettsia parkeri no Brasil.

Etiology of acute undifferentiated febrile syndrome (AUFS) is often unknown, leading to inaccurate diagnosis and treatment. Villeta town has been identified as an endemic area for spotted fever group (SFG) rickettsioses but little is known about possible amplifier hosts and other species different from. Besides, few studies have approached other AUFS etiologies in the region. We investigated the role of dengue, leptospirosis, rickettsioses, human anaplasmosis, and Q fever as possible causes of AUFS in patients from Villeta. Sera specimens and ticks from animals as well as ticks from vegetation were studied for the presence of different spp. Among 104 sera from patients with AUFS, 16.4%, 24.0%, and 2.9% patients seroconverted to dengue,, and SFG , respectively, with a case of probable coinfection or cross-reaction with. None of the samples were reactive for . Sera samples from 74 horses, 118 dogs, and 62 bovines were collected and showed 33.8%, 14.4%, and 50.0% of seroprevalence for SFG, respectively. A total of 1,287 ixodid ticks were collected from animals/vegetation and processed in pools for polymerase chain reaction. Among them, 1.7% was positive for genes, and, , and spp. were found. These results confirm the circulation of dengue, different SFG species and the relevance of other etiologies like leptospirosis and human anaplasmosis. Further studies must identify different epidemiological variables to establish proper surveillance and control programs.

The aim of this work was to detect and identify Rickettsia species in ticks collected in rural areas of Villeta, Colombia. Tick specimens were collected from domestic animals and walls of houses in five rural villages of Villeta town and from humans in Naranjal village (same town). Moreover, a flea collected from the same area was also processed. DNA was extracted and tested by conventional, semi-nested, and nested PCR reactions targeting rickettsial genes. In the ticks collected from humans from Naranjal village, a nymph of Amblyomma cajennense sensu lato was amplified using primers for ompA and sequenced (100% identity with "Candidatus Rickettsia amblyommii"). Last, three amplicons from the Ctenocephalides felis flea, corresponding to gltA, ompB, and 16S rRNA genes, showed high identity with R. felis (98.5%, 97.3%, and 99.2%, respectively) and "Candidatus Rickettsia asemboensis" (99.7% and 100%, respectively). To our knowledge, these results correspond to the first molecular detection in Colombia of "Candidatus Rickettsia amblyommii" and "Ca. Rickettsia asemboensis" in fleas.