Serologic evidence of rickettsial diseases associated with tick bites in workers of urban veterinary clinics.

BACKGROUND & OBJECTIVES: Rickettsial and other zoonotic diseases are a latent risk for workers of veterinary clinics. The objective of this study was to evaluate the prevalence and the associated risk factors of parasitosis caused by Rhipicephalus sanguineus, and to estimate the seroprevalence of rickettsial diseases in workers of urban veterinary clinics of Juárez city, México. METHODS: The participants of the study were recruited from 63 private veterinary clinics and hospitals. The serological analysis of the blood samples collected was carried out using immunofluorescence assay (IFA). The statistical analysis for prevalences, risk factors, and correlation was performed with the SAS program. RESULTS: In total, 167 veterinary workers were included in the study. The prevalence of tick bites was 40% (67/167), and the risk factors associated with the occurrence of bites included the activities performed in the clinic and the number of labour hours spent per week. About 21% (35/167) of participants were seropositive to R. rickettsii, 28% (47/167) to Ehrlichia chaffeensis, and 24% (40/167) to Anaplasma phagocytophilum. A correlation was observed between: the number of workers in the clinics and the proportion of tick bites (r2 = 0.865); the prevalence of bites and the seropositivity of the participants to at least one pathogen (r2 = 0.924); and the number of bites per individual and infection to pathogens (r2 = 0.838). INTERPRETATION & CONCLUSION: Workers in urban veterinary clinics are highly exposed to tick bites and, therefore, to the diseases they transmit. Hence, it is important to implement prevention measures and perform constant monitoring of these diseases.

Rickettsia japonica Infections in Humans, Xinyang, China, 2014-2017.

During 2014-2017, we screened for Rickettsia japonica infection in Xinyang, China, and identified 20 cases. The major clinical manifestations of monoinfection were fever, asthenia, myalgia, rash, and anorexia; laboratory findings included thrombocytopenia and elevated hepatic aminotransferase concentrations. Physicians in China should consider R. japonica infection in at-risk patients.

[Rickettsiosis after tick bite: A subtle clinic picture on many occasions, we must be vigilant]. / Rickettsiosis tras la picadura de una garrapata: una clínica sutil en muchas ocasiones, debemos estar atentos.

Rickettsia diseases are a group of tick-borne transmitted diseases, classified into 2 large groups: spotted fevers and typhus fevers. In addition, a new condition has been described recently, known as tick-borne lymphadenopathy. A retrospective series is presented of paediatric cases of rickettsia diseases diagnosed in 2013 and 2014. A total of 8 patients were included, of which 2 of them were diagnosed as Mediterranean spotted fever, and 6 as tick-borne lymphadenopathy. Rickettsia slovaca, Rickettsia sibirica mongolitimonae, and Rickettsia massiliae were identified in 3 of them. Aetiology, clinical features and treatment carried out in each of them are described. The interest of these cases is that, although most have a benign course, the high diagnostic suspicion and early treatment seem to be beneficial for its outcome.

A retrospective chart review study to describe selected zoonotic and arboviral etiologies in hospitalized febrile patients in the Republic of Armenia.

BACKGROUND: Scant information is available on the infectious causes of febrile illnesses in Armenia. The goal of this study was to describe the most common causes, with a focus on zoonotic and arboviral infections and related epidemiological and clinical patterns for hospitalized patients with febrile illnesses of infectious origin admitted to Nork Infectious Diseases Clinical Hospital, the referral center for infectious diseases in the capital city, Yerevan. METHOD: A chart review study was conducted in 2014. Data were abstracted from medical charts of adults (≥18 years) with a fever (≥38 °C), who were hospitalized (for ≥24 h) in 2010-2012. RESULTS: Of the 600 patients whose charts were analyzed, 76 % were from Yerevan and 51 % were male; the mean age (± standard deviation) was 35.5 (±16) years. Livestock exposure was recorded in 5 % of charts. Consumption of undercooked meat and unpasteurized dairy products were reported in 11 and 8 % of charts, respectively. Intestinal infections (51 %) were the most frequently reported final medical diagnoses, followed by diseases of the respiratory system (11 %), infectious mononucleosis (9.5 %), chickenpox (8.3 %), brucellosis (8.3 %), viral hepatitis (3.2 %), and erysipelas (1.5 %). Reviewed medical charts included two cases of fever of unknown origin (FUO), two cutaneous anthrax cases, two leptospirosis cases, three imported malaria cases, one case of rickettsiosis, and one case of rabies. Engagement in agricultural activities, exposure to animals, consumption of raw or unpasteurized milk, and male gender were significantly associated with brucellosis. CONCLUSION: Our analysis indicated that brucellosis was the most frequently reported zoonotic disease among hospitalized febrile patients. Overall, these study results suggest that zoonotic and arboviral infections were not common etiologies among febrile adult patients admitted to the Nork Infectious Diseases Clinical Hospital in Armenia.

A Case of Rickettsia felis Infection Imported From Nepal.

Rickettsia felis is an emerging spotted fever group pathogen that may be responsible for potentially life-threatening infections. A cosmopolitan distribution has been postulated though most human cases were observed in Africa and the Americas. We report an imported case from Nepal that occurred in an Italian tourist who presented with a 1-week history of fever, headache, nausea, vomiting, and a mild maculopapular rash 14 days after return.

[Update on SENLAT syndrome: scalp eschar and neck lymph adenopathy after a tick bite]. / Les nouveautés sur le syndrome SENLAT : Scalp Eschar and Neck LymphAdenopathy after Tick bite.

SENLAT syndrome, also known as TIBOLA/DEBONEL, is an emerging disease in France. The major symptoms are necrotic eschar on the scalp associated with painful cervical lymphadenopathy. It occurs mainly in women and children during the cold seasons after a bite by a Dermacentor tick, responsible for transmitting Rickettsia slovaca or Rickettsia raoultii. Cutaneous swabs are safe, easy and reliable tools that should be used routinely by physicians to confirm diagnosis. In this particular disease, they should be preferred to serology, which is less sensitive. Doxycycline is the antibiotic of choice for this syndrome.

First probable Australian cases of human infection with Rickettsia felis (cat-flea typhus).

Human infection with Rickettsia felis has been reported in most parts of the world, and R. felis has recently been confirmed in cat fleas in Western Australia. The clinical presentations of R. typhi and R. felis are similar, and in the past, the incidence of R. felis infection may have been underestimated. We describe the first reported cases of probable human R. felis infection in Australia. Two adults and three children in Victoria contracted a rickettsial disease after exposure to fleas from kittens. Molecular testing of fleas demonstrated the presence of R. felis but not R. typhi.

A focus of dogs and Rickettsia massiliae-infected Rhipicephalus sanguineus in California.

A recurrent focus of Rhipicephalus sanguineus infestation was investigated in a suburban area of southern California after reports of suspected Rocky Mountain spotted fever in two dogs on the same property. Abundant quantities of Rh. sanguineus were collected on the property and repeatedly from each dog, and Rickettsia massiliae DNA was detected by polymerase chain reaction (PCR). Whole blood and serum samples from four dogs were tested by using PCR and microimmunofluorescent assay for antibodies against spotted fever group rickettsiae. Serum samples from all four dogs contained antibodies reactive with R. massiliae, R. rhipicephali, R. rickettsii, and 364D Rickettsia but no rickettsial DNA was detected by PCR of blood samples. Serum cross-absorption and Western blot assays implicated R. massiliae as the most likely spotted fever group rickettsiae responsible for seropositivity. To our knowledge, this is the first detection of R. massiliae in ticks in California.

Human Infection with Rickettsia felis, Kenya.

To determine the cause of acute febrile illnesses other than malaria in the North Eastern Province, Kenya, we investigated rickettsial infection among patients from Garissa Provincial Hospital for 23 months during 2006-2008. Nucleic acid preparations of serum from 6 (3.7%) of 163 patients were positive for rickettsial DNA as determined by a genus-specific quantitative real-time PCR and were subsequently confirmed by molecular sequencing to be positive for Rickettsia felis. The 6 febrile patients' symptoms included headache; nausea; and muscle, back, and joint pain. None of the patients had a skin rash.

Rickettsia parkeri infection after tick bite, Virginia.

We describe a man with a febrile illness and an eschar that developed at the site of a tick bite. Rickettsia parkeri was detected and isolated from the eschar. This report represents the second documented case of R. parkeri rickettsiosis in a US serviceman in eastern Virginia.

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.

A metabolic basis for fibromyalgia and its related disorders: the possible role of resistance to thyroid hormone.

It has long been recognized that the symptom complex of fibromyalgia can be seen with hypothyroidism. Hypothyroidism may been categorized, like diabetes, into type I (hormone deficient) and type II (hormone resistant). Most cases of fibromyalgia fall into the latter category. The syndrome is reversible with treatment, and is usually of late onset. It is likely more often acquired than due to mutated receptors. Now that there is evidence to support the hypothesis that fibromyalgia may be due to thyroid hormone resistance, four major questions appear addressable. First, can a simple biomarker be found to help diagnose it? Second, what other syndromes similar to Fibromyalgia may share a thyroid-resistant nature? Third, in non-genetic cases, how is resistance acquired? Fourth, what other methods of treatment become available through this new understanding? Preliminary evidence suggests that serum hyaluronic acid is a simple, inexpensive, sensitive, and specific test that identifies fibromyalgia. Overlapping symptom complexes suggest that chronic fatigue syndrome, Gulf war syndrome, premenstrual syndrome, post traumatic stress disorder, breast implant silicone sensitivity syndrome, bipolar affective disorder, systemic candidiasis, myofascial pain syndrome, and idiopathic environmental intolerance are similar enough to fibromyalgia to merit investigation for possible thyroid resistance. Acquired resistance may be due most often to a recently recognized chronic consumptive coagulopathy, which itself may be most often associated with chronic infections with mycoplasmids and related microbes or parasites. Other precipitants of thyroid resistance may use this or other paths as well. In addition to experimentally proven treatment with supraphysiologic doses of thyroid hormone, the thyroid-resistant disorders might be treatable with anti-hypercoagulant, anti-infective, insulin-sensitizing, and hyaluronolytic strategies.

Seroepidemiology of Rickettsia africae infection in Norwegian travellers to rural Africa.

Rickettsia africae is the causative agent of African tick bite fever (ATBF), an acute febrile illness frequently accompanied by inoculation eschars, regional lymphadenitis, myalgia and severe headache. Recently, ATBF has been recognized as an emerging health problem for international travellers to rural sub-Saharan Africa. To estimate the incidence, risk factors for and proportion of symptomatic cases of travel-associated R. africae infection, we performed a seroepidemiological study of 152 first-time Norwegian travellers to rural areas in sub-Equatorial Africa. Seropositivity was based on the detection of specific antibodies to R. africae in microimmunofluorescence and/or Western blotting assays. Thirteen (8.6%) travellers were seropositive to R. africae. Eight (62%) seropositive travellers reported symptoms consistent with ATBF; of these, 2 had received antirickettsial therapy. Using multiple logistic regression, the following factors were found to be significantly associated with seropositivity: hunting as the purpose of travel [odds ratio (OR) 10.1; 95% confidence interval (CI) 1.5-69; p=0.019] and stay in rural areas of > 7 d (OR 6.0; 95% CI 1.5-24; p=0.012). This first seroepidemiological study on travel-associated R. africae infection suggests that the infection may be common in international travellers to rural sub-Saharan Africa but that most cases are asymptomatic or clinically mild and self-limited.

Human infections tick-transmitted.

In this monograph are analysed the principal infections transmitted by ticks and particularly those interesting Europe and North America. Besides the main species of these arthropods are described in consideration of their characteristics and geographic diffusion. In particular the infections caused by Borrelia genus and tick born encephalitis virus are treated more exhaustively in consideration of their potential severity and because the diagnosis of these infections is sometimes difficult. However also the main rickettsial infections transmitted by ticks are reported together the hemorragic fevers transmitted by such arthropods. In particular it is exhaustively analysed the Mediterranean tick fever in consideration of its presence in some regions of Italy and of the wrong opinion of considering this pathology not very severe. Lastly has been included a treatment about some emergent infections transmitted by ticks, like as the ehrlichiosis and babesiasis, but also the mention of tularaemia that can be considered a re-emergent infection, also in consideration of the epidemic focus now present in Kossovo. The above-mentioned pathologies are analysed also as regards the laboratory diagnosis (direct and serologic methods), the therapeutic treatment and the prophilaxis, both directed against the arthropods vectors and that of individual type, employing also some vaccines, when disposable.

[Rickettsia infections in Portugal]. / Rickettsioses em Portugal.

After a brief introduction about rickettsioses, we analyse Mediterranean Spotted Fever (MSF) in Portugal, and review Portuguese medical literature. We focussed on the seasonal summer pattern of the disease. MSF is very frequent in Portugal, nearly 1,000 cases are reported every year and young age groups are the most afflicted. Although usually regarded as a benign condition, MSF has emerged as a potentially lethal disease in recent years. The clinical presentation is protean, but usually suggestive enough to allow a clinical diagnosis. The complications are well documented, elderly and people with chronic debilitating diseases being the most affected. Q fever is also endemic in Portugal, although with more modest numbers (about 50 cases a year). Serological studies, however, suggest a higher incidence, probably because the disease is unfamiliar to many clinicians and, as such, it is difficult to diagnose and, consequently, then an important number of subclinical or self-limited cases. In Portugal, fever with hepatic involvement is the most common clinical presentation. Other less frequent clinical forms are atypical pneumonia and CNS involvement. Chronic Q fever is a rare condition.

Detection of Rickettsia japonica in Haemaphysalis longicornis ticks by restriction fragment length polymorphism of PCR product.

PCR was applied to the detection of Rickettsia japonica, the causative agent of Oriental spotted fever (OSF), in ticks collected at two sites of the Muroto area on Shikoku Island, a major area in Japan where OSF is endemic. Primer pair Rr190.70p and Rr190.602n of the R. rickettsii 190-kDa antigen gene sequence of Regnery and others (R.L. Regnery, C.L. Spruill, and B.D. Plikaytis, J. Bacteriol. 173:1576-1589, 1991) primed the DNA extracted from Haemaphysalis longicornis ticks but not those extracted from Haemaphysalis formosensis, Haemaphysalis flava, Haemaphysalis hystricis, or Amblyomma testudinarium ticks. Digestion of the amplification product with the restriction endonucleases PstI and AluI produced the restriction fragment length polymorphism pattern specific to R. japonica. The HindIII and MspI digests gave restriction fragment length polymorphism patterns identical to those of the PCR product from R. japonica DNA. Hemolymph preparations of H. longicornis ticks were demonstrated to contain rod-shaped organisms that were detected by immunofluorescence with the monoclonal antibody specific to R. japonica species. The primer pair did not amplify the DNA of a laboratory colony of H. longicornis ticks originally collected at an area where OSF is not endemic. Our results provided evidence that H. longicornis ticks might be an arthropod reservoir for R. japonica and a vector of OSF.