An Evaluation of the Hitit Index in Differential Diagnosis of Crimean-Congo Hemorrhagic Fever in the Emergency Department

Background and Objectives: Crimean-Congo Hemorrhagic Fever (CCHF) is a viral zoonotic infection, which is seen over a wide geographic area. The mortality rate is in inverse proportion to the ability of patients to access healthcare services. Therefore, early identification of patients is extremely important. The aim of this study was to test the sensitivity and specificity of the Hitit Index in the differentiation of CCHF cases at the time of presentation at the Emergency Department and to evaluate the agreement of this index with molecular (CCHFV RNA) and/or serological diagnostic tests (ELISA-CCHF IgM). Materials and Methods: The patients included were those who presented at the Emergency Department (ED) with the complaint of a tick bite or those identified as potential CCHF cases as a result of complaints and/or laboratory findings. For cases that met the study inclusion criteria, the Hitit Index score was calculated automatically from the parameters included in the index formula uploaded to the automation system in the ED at the time of presentation. Through comparisons of the agreement of the Hitit Index with the CCHFV-RNA and/or IgM results the power of the Hitit Index for differentiation of CCHF cases in ED was evaluated. Results: The data of 273 patients were analyzed. There was a history of tick bite in 236 (86%) cases. Of the evaluated cases, 110 (40.2%) were hospitalized; CCHF positivity was determined in 72 (26.4%). The Hitit Index values calculated in ED and at 24 h after hospitalization were determined to be significant in the prediction of the CCHF cases (p < 0.001, AUC = 0.919 (0.887-0.951); p < 0.001, AUC = 0.902 (0.841-0.962). For a cut-off point of 0 of the Hitit Index evaluated in ED, the classification success was found to have a sensitivity of 75% and specificity of 88% (PPV-NPV). For a cut-off point of 0 of the Hitit Index evaluated at 24 h after hospitalization, the classification success was found to have a sensitivity of 79.7% and specificity of 84% (PPV-NPV). Conclusions: The defined form of the Hitit Index can be used in the differentiation of CCHF cases in ED with high sensitivity and specificity levels. Just as evaluation with the Hitit Index prevents unnecessary hospitalization, it can also contribute to reducing mortality rates with the early identification of CCHF cases.

The social representations of diagnosing Lyme disease

Social science studies on the controversy surrounding Lyme disease (LD) focused on the opposition between the "mainstream" and biomedical approach on one side and the "Lyme-literate" one on the other side, the latter claiming the existence of the chronic form of LD. The qualitative and exploratory study 'C18-48 Quali-Explo-PIQTIQ' (2019) investigated the social representations of LD in patients bitten by a tick. Twenty-four semi-structured interviews were conducted in three French medical units. Thematic and patient trajectory analyses were performed. Our results showed that, after the tick bite, some patients presented an "illness without disease" condition, characterised by uncertainty. In some cases, they consulted "Lyme-literate" health providers and received a diagnosis of chronic LD. This diagnosis was obtained by prescribing unassessed biological testing, providing an objective result and clinical categorisation. Unlike literature on the "Lyme-literate" approach, this diagnostic procedure involved some biomedical operations.

Analysis of selected serological parameters in patients with diagnosed Lyme borreliosis and in seropositive patients with no clinical symptoms

OBJECTIVES

The aim of the study was to analyze some metalloproteinases, cytokines, and chemokines in LB patients and healthy seropositive subjects. The presence of IgM/IgG antibodies against specific Borreliella antigens was analyzed in the presence or absence of clinical manifestations of LB.

MATERIAL AND METHODS

The study involved 38 patients diagnosed with LB and arthralgia and/or arthritis symptoms, and 57 foresters presenting no clinical symptoms of LB. The ELISA test was applied for general screening of anti-Borreliella IgM/IgG. Western blot was used for confirmatory diagnosis of LB for the positive and borderline results. Serum IL-2, IL-4, IL-6, IL-10, IL-17A, IFN-γ, TNF, IL-8, CCL5, CXCL9/MIG, CCL2/MCP-1, CXCL10/IP-10 concentrations were measured with the use of the Human Cytometric CBA test. The concentration of MMP-2 and MMP-9 in the serum was determined with the use of ELISA tests.

RESULTS

Analysis of the cytokines and chemokines revealed that only the concentration of IL-2 was significantly higher (2.4 pg/m; p=0.00641) in patients with LB symptoms than in the seropositive individuals (0.4 pg/ml). The MMP2 concentration was significantly higher (233.3 ng/ml; p=0.00294) in patients with clinical manifestations of LB than in those occupationally exposed to tick bites, but did not have anti-Borreliella antibodies (192.0 ng/ml).

CONCLUSIONS

The presence of IgG antibodies against a number of Borreliella antigens and the differences in the IL-2 and MMP2 levels in seropositive or seronegative individuals and symptomatic LB patients, may indicate differences in the intensity of the immune response to the infection and, consequently, may induce development of clinical manifestations of the disease in seropositive and seronegative individuals.

Two Atypical Cases of Tick Bites: A Fully Engorged Tick and Multiple Ticks

Ticks have a cosmopolitan distribution and, as such, are also found in Japan. Ticks are typically ectoparasites of wild animals, however, humans can also be bitten when visiting environments inhabited by ticks. Herein, we describe two cases with atypical tick bites. Case 1 was an elderly Japanese male patient who presented with a fully engorged tick measuring 20 × 17 × 8 mm; it is rare for ticks to attain a length of 20 mm. Case 2 was an elderly Japanese female with severe dementia who presented with multiple tick bites, which is rare, after going missing for 6 days before being found in a densely wooded area. Ticks are responsible for the transmission of many infectious agents, such as bacteria, viruses and parasites. The National Institute of Infectious Diseases and the Ministry of Health, Labour and Welfare regularly inform citizens of the risks posed by tick bites. However, the tick bites could not be prevented in our patients. Further edification about tick bites, tick-borne diseases, and their prevention are considered necessary in Japan.

Systematic review and meta-analysis of tick-borne disease risk factors in residential yards, neighborhoods, and beyond

BACKGROUND

Exposure to blacklegged ticks Ixodes scapularis that transmit pathogens is thought to occur peri-domestically. However, the locations where people most frequently encounter infected ticks are not well characterized, leading to mixed messages from public health officials about where risk is highest.

METHODS

We conducted a systematic review and meta-analysis on spatial risk factors for tick-borne disease and tick bites in eastern North America. We examined three scales: the residential yard, the neighborhood surrounding (but not including) the yard, and outside the neighborhood. Nineteen eligible studies represented 2741 cases of tick-borne illness and 1447 tick bites. Using random effects models, we derived pooled odds ratio (OR) estimates.

RESULTS

The meta-analysis revealed significant disease risk factors at the scale of the yard (OR 2.60 95% CI 1.96 - 3.46), the neighborhood (OR 4.08 95% CI 2.49 - 6.68), and outside the neighborhood (OR 2.03 95% CI 1.59 - 2.59). Although significant risk exists at each scale, neighborhood scale risk factors best explained disease exposure. Analysis of variance revealed risk at the neighborhood scale was 57% greater than risk at the yard scale and 101% greater than risk outside the neighborhood.

CONCLUSIONS

This analysis emphasizes the importance of understanding and reducing tick-borne disease risk at the neighborhood scale. Risk-reducing interventions applied at each scale could be effective, but interventions applied at the neighborhood scale are most likely to protect human health.

TRIAL REGISTRATION

The study was registered with PROSPERO: CRD42017079169 .

Granuloma Annulare and Morphea: Correlation with Borrelia burgdorferi Infections and Chlamydia-related Bacteria

A retrospective study of 109 skin biopsies with granuloma annulare (GA) or morphea histology from patients with suspected tick bite was performed. Biopsies were tested for cutaneous Borrelia burgdorferi DNA using PCR. The same biopsies were analysed for tick-borne novel agents, Chlamydia-related bacteria (members of the Chlamydiales order), using a PCR-based method. Borrelia DNA was detected in 7/73 (9.6%) biopsies with GA and in 1/36 (2.8 %) biopsies with morphea, while Chlamydiales DNA was found in 53/73 (72.6%) biopsies with GA and 25/34 (73.4%) biopsies with morphea. All Borrelia DNA-positive GA samples were also positive for Chlamydiales DNA. The Chlamydiales sequences detected in GA were heterogeneous and contained Waddliaceae and Rhabdochlamydiaceae bacteria, which are also present in Ixodes ricinus ticks, while the Chlamydiales sequences detected in morphea closely resembled those found in healthy skin. In conclusion, tick-mediated infections can trigger GA in some cases, while correlation of either Borrelia or Chlamydiales with morphea is unlikely.

Assessment of using recombinant Ixodes ricinus AV422 saliva protein for confirmation of tick bites in hunting dogs as naturally infested hosts

Due to the recorded spreading of ticks in past years, a higher incidence of tick-borne diseases (TBDs) can be expected in the future in endemic areas, but can also pose an emerging public health concern in areas where they have not yet been recognized. Assessment of the exposure of vulnerable hosts to ticks would be a very helpful tool for TBD epidemiological studies, as well as for their proper managing. To confirm previous tick bites, the method of choice is detection of antibodies in host serum as markers developed against injected tick saliva proteins during feeding. We recently showed that the recombinant form of Ixodes ricinus AV422 saliva protein (rIrAV422) can serve for detection of markers in experimentally infested rats. Here we examine whether it can be used in the same manner in naturally exposed hosts. We chose hunting dogs as good sentinel animals. The study group consisted of 15 dogs that varied in breed, age, sex, previous tick infestation history and repellent treatment. Western blot analysis with rIrAV422 as an antigen confirmed the presence of tick bite markers in all analysed dogs. For some of the dogs, their previous tick infestation history was unclear, which emphasizes the usefulness of rIrAV422 for revealing it. Since hunting dogs are naturally infested with different ticks, the potential of rIrAV422 in assessment of general exposure to ticks is highlighted. Use of rIrAV422 can also be helpful in veterinary practice and research as a tool for validation of the efficiency of tick repellent products.

Predictors of Crimean-Congo hemorrhagic fever in the Emergency Department

OBJECTIVE

Crimean-Congo hemorrhagic fever (CCHF) is an acute illness affecting multiple organ systems characterized by thrombocytopenia, and/or leukopenia, elevated levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and creatine kinase (CK) and it has a case-fatality of 8% to 80%. In this article, we aimed to determine the clinical and laboratory findings that predicts the disease on admission.

PATIENTS AND METHODS

We retrospectively analyzed the medical data of the patients admitted to our emergency department (ED) due to tick bite. These patients were divided into two groups according to their transcriptase-polymerase chain reaction (RT-PCR) test results. Findings of PCR (+) (Group 1) and PCR (-) (Group 2) patients were compared.

RESULTS

Epistaxis was found to be statistically significant clinical finding in Group 1. Also, while aspartate transaminase (AST) levels and potassium (K) level were significantly higher, platelet count and white blood count (WBC) were significantly lower in Group 1 when compared to Group 2.

CONCLUSIONS

Predictors of CCHF in the ED are epistaxis, leukopenia, thrombocytopenia and elevated K and AST levels. In our study, the fatality rate of CCHF was found to be 21.6%.

A brown dog tick (Rhipicephalus sanguineus) bite at sea

Medical Officers (MOs) and Medical Branch Ratings (MBRs) must maintain an awareness of the risk of vector-borne diseases among deployed personnel. Personnel working in the maritime environment may not expect to be at risk of tick bites, as ticks typically occupy habitats with dense vegetation such as forests or scrub land. However, tick-borne pathogens can cause serious and sometimes fatal disease, and therefore the risk of tick bites and associated diseases should be recognised. We present a case of a tick bite in a member of a ship's company eight days after leaving port. The tick was identified as a brown dog tick (Rhipicephalus sanguineus), a species known to thrive indoors. We describe several important tick-borne diseases which can be transmitted by R. sanguineus and explore best practice for tick removal and aftercare. Finally, we outline the appropriate management of suspected tick-borne disease in deployed personnel in the maritime environment.

First report on the seroprevalence of the Crimean-Congo haemorrhagic fever virus, a tick-borne virus, in Malaysia's Orang Asli population

OBJECTIVE

The Crimean-Congo haemorrhagic fever virus (CCHFV), which is transmitted by the ticks of Hyalomma spp. in general and H. marginatumin particular, can cause severe disease in humans, with mortality rates of 3-30%. Other than from the bites of infected ticks, CCHFV can also be transmitted through contact with patients with the acute phase of infection or contact with blood or tissues from viraemic livestock.  Outbreaks of human cases of haemorrhagic manifestations have been documented since 1945 and described in parts of Africa, Asia, Eastern Europe and the Middle East and most recently India in 2011. In addition, serological evidence of the disease has been reported in some countries where no human cases were reported. As regional neighbours China and India have been affected by this virus, this study was conducted to determine the seroprevalence of CCHFV among Orang Asli population of Malaysia as the most at risk people who residing in the deep forests.

PATIENTS AND METHODS

A total of 682 serum samples were collected from the Orang Asli population residing in eight states in peninsular Malaysia and analysed for the presence of anti-CCHFV immunoglobulin G (IgG) using a commercial enzyme-linked immunosorbent assay kit.

RESULTS

The study subjects comprised 277 (40.6%) men and 405 (59.4%) women. However, anti-CCHFV IgG was detected in only one female serum sample (0.1%). The presence of anti-CCHFV IgG could not be correlated to age or sex from these findings.

CONCLUSIONS

The results of this screening survey showed that the seroprevalence of the anti-CCHFV IgG among Malaysia's Orang Asli population is too low for detection or totally negative compared with that in neighbouring countries, such as India and China.

[Amblyomma spp. case related to overseas travel]

Ticks are a threat to human health by blood sucking and vectoring many disease agents. Tick-borne diseases are seen all over the world and play an important role in the dissemination of diseases. Although many of the tick species are present in Turkey, Amblyomma genus is seen more in South America and Africa. In this case,a person returning to the country after travelling to Africa who presented to the hospital complaining of tick bites and brought ticks to the parasitology laboratory was identified as Ablyomma spp. nymph. This case is a report concerning care of tick bites when travelling abroad and shows that these ticks can transmit disease agents from abroad.

Arthropod bites

The phylum Arthropoda includes arachnids and insects. Although their bites typically cause only local reactions, some species are venomous or transmit disease. The two medically important spiders in the United States are widow spiders (Latrodectus), the bite of which causes intense muscle spasms, and the brown recluse (Loxosceles), which may cause skin necrosis. Widow bites usually respond to narcotics, benzodiazepines, or, when necessary, antivenom. Most recluse bites resolve uneventfully without aggressive therapy and require only wound care and minor debridement. Tick bites can transmit diseases only after prolonged attachment to the host. Treatment of clothing with permethrin and proper tick removal greatly reduce the risk of infection. Ticks of medical importance in the United States include the black-legged tick, the Lone Star tick, and the American dog tick. The prophylactic use of a single dose of doxycycline for Lyme disease may be justified in high-risk areas of the country when an attached, engorged black-legged tick is removed. Bites from fleas, bedbugs, biting flies, and mosquitoes present as nonspecific pruritic pink papules, but the history and location of the bite can assist with diagnosis. Flea bites are usually on ankles, whereas mosquito bites are on exposed skin, and chigger bites tend to be along the sock and belt lines. Antihistamines are usually the only treatment required for insect bites; however, severe mosquito reactions (skeeter syndrome) may require prednisone. Applying insect repellent containing diethyltoluamide (DEET) 10% to 35% or picaridin 20% is the best method for preventing bites.

A prospective study among patients presenting at the general practitioner with a tick bite or erythema migrans in The Netherlands

Background

We performed a nationwide prospective study on the transmission risk for Borrelia to humans, investigating symptoms and serology at enrolment and three months after tick bites, and after standard treatment for erythema migrans (EM). Aiming to quantify the infection risk at point of care by physicians, we explored risk factors such as tick testing for Borrelia and assessment of the duration of the tick's blood meal.

Methods and Findings

Questionnaires, blood samples and ticks from patients who consulted one of 307 general practitioners for tick bites (n = 327) or EM (n = 283) in 2007 and 2008, were collected at enrolment and three months later at follow-up. Borrelia burgdorferi sensu lato DNA was detected in 29.3% of 314 ticks, using PCR/reverse line blot and real-time PCR on the OspA gene. Seroconversion in C6 ELISA, IgM or IgG immunoblots for Borrelia-specific antibodies was observed in 3.2% of tick bite cases. Fourteen tick bite cases had evidence of early Borrelia infection, of which EM developed among seven cases. The risk of developing EM after tick bites was 2.6% (95%CI: 1.1%–5.0%), and the risk of either EM or seroconversion was 5.1% (95%CI: 2.9%–8.2%). Participants with Borrelia-positive ticks had a significantly higher risk of either EM or seroconversion (odds ratio 4.8, 95%CI: 1.1–20.4), and of seroconversion alone (odds ratio 11.1, 95%CI: 1.1–108.9). A third (34%) of the cases enrolled with EM did not recall preceding tick bites. Three EM cases (1%) reported persisting symptoms, three months after standard antibiotic treatment for EM.

Conclusions

One out of forty participants developed EM within three months after tick bites. The infection risk can be assessed by tick testing for Borrelia at point of care by physicians. However, further refining is needed considering sensitivity and specificity of tick tests, accuracy of tick attachment time and engorgement.

Epidemiology of Lyme disease among workers of forest inspectorates in Poland

INTRODUCTION

Lyme disease (Lyme borreliosis, LB) is a systemic tick-borne disease. Its symptoms include dermatological changes and systemic manifestations such as musculoskeletal, neurologic, and cardiac. The etiologic agent of LB is a spirochete known as Borrelia burgdorferi (B.b.) with rodents and small mammals as its animal reservoir. In Poland, there are approximately 9-10 cases of the disease per 100,000 inhabitants each year.

OBJECTIVE

Analyis of the incidence of Lyme borreliosis and the clinical picture of the disease among foresters.

MATERIAL AND METHODS

The research material consisted of data collected in a diagnostic survey conducted by use of a survey questionnaire method. The study involved 100 randomly selected workers of the forest inspectorate in Podkarpackie Voivodeship. Group I consisted of men between 30-45 years old with an average length of service of 14 years (48%); group II consisted of men between 45-55 years old with an average length of service of 24 years (52%).

RESULTS

Only 25% of the foresters from the first group, younger in age and with shorter service, had never been bitten by a tick, while 60% were bitten once, and 15% had been repeatedly bitten. In the second group, older in age and with longer service, only 3% had never been bitten by a tick, 35% were bitten once, while 62% had been repeatedly bitten. LB was diagnosed in 30% of the research participants from the first group and in 45% from the second group. Most frequently, LB was diagnosed as a result of the presence of erythema migrans (55%), ELISA test (20%), and Western Blot test (22%). The most frequent symptoms among the participants were: erythema migrans (45%), fever and shivers (35%), muscle pain and cramps (15%), other symptoms (5%). Permanent presence of symptoms was reported by 70% of the participants, 25% experienced symptoms periodically, and 5% only sporadically.

CONCLUSIONS

LB occurs more frequently among foresters older in age and with longer service (45%); in the younger group--30%. Despite knowledge on preventive methods, there is no effective preventive method for this disease.