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At least 19 recordsLinked to original sources
PubMed2026

Widespread circulation of Alongshan virus in Austria and serological evidence for infection in humans: a nationwide molecular and serological observational study.

BACKGROUND: Alongshan virus, a segmented RNA virus in the Jingmenvirus group of flaviviruses, was first identified in 2017 in China in patients with tick-borne encephalitis-like illness. Alongshan virus has since been detected in ticks and mammals in several European countries. In this study, we aimed to characterise the temporal and geographical distribution of Alongshan virus in Austria through nationwide tick surveillance combined with serological and molecular screening in individuals with suspected tick-borne encephalitis or tick exposure. METHODS: In this nationwide molecular and serological observational study, we conducted a PCR-based screening of ticks collected across Austria in 2024, using flagging, animal hosts, and citizen submissions. We also collated genomic data from stored nucleic acid extracts from ticks collected in Austria in 2005 and 2013 in previous surveillance studies and stored extracts of paired tick-human samples collected between 2015 and 2018. Alongshan virus-positive tick samples were subjected to whole-genome sequencing and phylogenetic analysis. In addition to tick samples, blood samples from Austrian patients with reported tick bite or suspected tick-borne encephalitis, submitted to the National Reference Center for Human Arbovirus Infections, Austria, were screened for Alongshan virus infection and subjected to serological and molecular testing. FINDINGS: 2952 ticks were collected between Feb 1, 2024, and Dec 6, 2024, from 29 (83%) of 35 NUTS-3 regions in Austria; the median detection rate for Alongshan virus was 1·2% (IQR 0·4-3·5). In addition, 1816 archived tick samples were analysed, with three testing positive for Alongshan virus. For the virus-positive samples, phylogenetic analysis showed that sequences from Austria grouped within the European clade, with Austrian sequences from the same region showing high sequence similarity. 1361 human serum samples collected between March 1, 2023, and May 16, 2025, were assessed for anti-Alongshan virus IgG antibodies. Two individuals had high antibody titres against Alongshan virus proteins VP1a and VP2. INTERPRETATION: Our study shows detection of Alongshan virus in archived tick samples dating back to 2005, representing the earliest documented occurrence of the virus to date and suggesting that Alongshan virus has been circulating in Austria for at least two decades. The detection of Alongshan virus-specific antibody titres in two individuals suggests past infection and previously unrecognised exposure. These results highlight the need for continued molecular surveillance of tick populations and serological monitoring in humans to define the epidemiology and public health relevance of Alongshan virus in Europe. FUNDING: One Health surveillance and Vector monitoring for cross-border pathogens (OH SURVector) and UNITED4Surveillance.

Adolescent↗
PubMed2026

Harnessing survey data across multiple demographic groups in Illinois to assess survey questions and reveal insights about ticks and tick-borne disease risk: a meta-comparison study.

BACKGROUND: Ticks and tick-borne diseases (TTBDs) are major public and veterinary health issues, existing at the intersection of behavioral, environmental, ecological, climatic, and entomological factors. Knowledge, attitudes, and practices (KAP) surveys have become an insightful tool to yield information regarding the behavioral factors that can predispose individuals to TTBDs. Here we present a unique meta-comparison study of six KAP surveys on TTBDs conducted in Illinois among various demographics: farmers, Extension workers, general public, veterinary, human medicine, and public health professionals. Our goals were multi-fold: (a) to develop an approach to compare KAP surveys used across several stakeholders on a subject of public health concern (i.e., TTBD risk), (b) to analyze the usefulness of questions for revealing information on TTBDs across varied demographic groups in Illinois, and (c) to reveal qualitative insights from the open text survey responses across these surveyed groups. METHODS: We conducted comparative and item response theory (IRT) analysis of all the surveyed questions, which yielded a final set of 39 questions on knowledge and practices, most of them with discriminatory power. Independent textual analysis of the survey responses led to the development of eight separate sub-categories across three main super categories: ticks and tick-borne disease (TBD) risk, TBD treatment and management, and TBD prevention. RESULTS: This study not only introduces a novel approach for comparing multiple KAP surveys on the topic of TTBDs, but also highlights gaps regarding TTBD knowledge, perceptions, and prevention measures among a variety of stakeholders and calls for tailored training and awareness campaigns to reduce the burden of TBDs in the Midwestern US. This meta-comparison approach unveils additional insights from the combined analyses of the KAP surveys. We also discuss perspectives of the surveyed demographics, their experiences with TTBDs, and provide recommendations for future public health efforts. CONCLUSION: These results can guide public health campaigns around TBDs in the United States and help reduce the increasing burden of TBDs on humans and animals.

Animals↗
PubMed1979

Field study of the relationship between skin-sensitizing antibody production in the cottontail rabbit, Sylvilagus floridanus, and infestation by the rabbit tick, Haemaphysalis leporispalustris (Acri: Ixodidae).

The resistance of cottontail rabbits to tick feeding appears correlated with the rabbits' development of skin-sensitizing antibodies. Resistance appeared to be greatest in adult rabbits which had been repeatedly infested with ticks. Rabbits with little exposure to ticks, usually the young cottontails, showed little or no skin-sensitizing antibody present in their blood and usually had relatively high tick loads when compared with adult rabbits. Models used to interpret the data show promise as tools for predicting tick population fluctuations and, perhaps, incidence of vector borne disease outbreaks. The existence of resistance to tick attachment has important implications for the host-parasite relationship. The research lends support to the hypothesis that the resistance may function as a homeostatic regulatory mechanism capable of maintaining the size of the tick population in equilibrium with the size of the rabbit population. In this way, host resistance may be advantageous to the parasite as well as to the host.

Animals↗
PubMed1978

Colorado tick fever: clinical, epidemiologic, and laboratory aspects of 228 cases in Colorado in 1973-1974.

During 1973 and 1974, we looked for cases of Colorado tick fever throughout Colorado; 228 cases were identified. Although 90% of the patients reported exposure to ticks before illness, only 52% were aware of an actual tick bite. Typical symptoms of fever, myalgia, and headache were common, but gastrointestinal symptoms were also prominent in 20% of the patients. Twenty percent were hospitalized; no deaths or permanent sequelae were noted. Persistent viremia (greater than or equal to 4 weeks) was found in about half of the cases; this finding was not associated with the occurrence of prolonged symptoms (greater than or equal to 3 weeks), which were also reported in half of the cases. One patient became reinfected with the virus. Increasing tourism in endemic areas and the frequent occurrence of prolonged or biphasic illnesses provide the potential for patients with Colorado tick fever to seek medical care anywhere in the United States.

Adolescent↗
PubMed1979

Tick-borne relapsing fever in Colorado. Historical review and report of cases.

Since 1915 the front range of the Colorado Rocky Mountains has been postulated as a focus of endemic tick-borne relapsing fever. However, the disease has rarely been identified: only two cases have been reported in Colorado since 1944. Three sporadic cases in 1977--tightly grouped geographically and temporally--prompted an epidemiologic review. Tick-borne relapsing fever should be considered in the differential diagnosis of recurrent paroxysmal fever--with or without known presence of ticks--whenever exposure in an endemic area is part of a patient's history.

Adult↗
PubMed1978

Babesia microti infection in man: evaluation of an indirect immunofluorescent antibody test.

An indirect immunofluorescent antibody test was used to detect antibody to Babesia microti in human sera. Nine patients from Nantucket Island, Massachusetts infected with B. microti had serum titers greater than or equal to 1,024. Of 84 control sera from New York City residents, 246 sera from patients with possible exposure to ticks, and 36 sera from patients with suspected or confirmed tick bites, none was reactive at titers of 1:16 or above. The within-test reproducibility was within one fourfold dilution in 95% of trials. Test-to-test reproducibility was within one fourfold dilution in 33% of trials and within two fourfold dilutions in 100% of trials. Although cross-reactions among infected patients' sera and antigens of B. argentina, B. equi, B. bigemina, Plasmodium vivax, P. falciparum, and P. brasilianum were common, titers were highest to the homologous antigen.

Animals↗
PubMed1979

Immunization against bovine tropical theileriosis, using 60Co-irradiated infective particles of Theileria annulata (Dschunkowsky and Luhs 1904) derived from ticks.

Portions of ground supernate material from Theileria annulata-infected and prefed adults of the Hyalomma anatolicum anatolicum were irridiated by 60Co source at 0, 3, 5, 6, 7, or 9 krads. These portions were injected subcutaneously into different groups of cross-bred calves. The calves injected with 0-, 3-, or 5-krad irradiated tick supernate had severe reactions (rectal temperature 39.8 to 41.6 C, two- to fourfold enlargement of prescapular lymph gland, mean peak parasitemia 27.3% to 32.5% infected erythrocytes, decreased PCV 41.7% to 60.7%, and hemoglobin concentration 37.5% to 50.8%), and many died, whereas those injected with 6- or 7-krad irradiated tick supernate had minimal reactions (rectal temperature 39.2 to 39.8 C, slight enlargement of prescapular lymph gland, parasitemia less than 1%, decrease packed cell volume 15.1%, and hemoglobin concentration 20.1%), with no mortality. All surviving calves injected with nonirradiated (0-) or 3-, 5-, 6-, or 7-krad irradiated tick supernate developed comparable indirect fluorescent antibody titers and were resistant to challenge exposure with infective material from 30 ticks. The calves injected with 9-krad irradiated tick supernate showed no reactions and did not develop indirect fluorescent antibody titers; they were also susceptible to challenge exposure with infective tick material.

Animals↗
PubMed1979

Tick-borne tularemia presenting as ulcerative lymphadenitis.

In a patient with suppurative lymphadenitis who fails to respond to antibiotics routinely used for pyogenic adenitis, the diagnosis of tularemia should be considered if there is good evidence for recent tick or other insect exposure. A trial of streptomycin therapy may be indicated, pending culture and serology results, in any patient whose signs and symptoms strongly suggest this diagnosis.

Arachnid Vectors↗
PubMed1975

Effect of humoral antibodies on the course of Theileria parva infection (East Coast fever) of cattle.

A study was made of the effects of serum and gamma-globulins from vaccinated cattle (donor cattle) given to cattle (principals) exposed to Theileria parva infection (East Coast fever (ECF)). The principals were treated with normal serum, with serum containing high antibody titer against T parva (as evaluated by the indirect fluorescent antibody (IFA) technique), or with globulins prepared from normal and from immune serums. For exposure, the principals were inoculated with standardized suspension of the tick Rhipicephalus appendiculatus containing T parva infective particles. Comparison was made between treatments with normal serum and globulin and treatments with immune serum and globulin, using observations of time lapse after exposure to febrile response (39.5 C), to appearance of T parva macroschizonts, and to death. In addition, hematologic changes were determined. Neither the establishment of infection nor the clinical and hematologic changes in the principals were influenced by their treatment with immune serum or concentrated globulins; all died of ECF. Humoral antibodies did not protect cattle against fatal ECF, nor was enhancement of T parva infection observed.

Animals↗
PubMed1977

Laboratory-acquired Rocky Mountain spotted fever. The hazard of aerosol transmission.

Nine patients with laboratory-acquired Rocky Mountain spotted fever were seen during the period 1971 to 1976. Investigation of each case revealed either definite or probable exposure to an aerosol containing infectious rickettsiae; in no case was there evidence of parenteral exposure either by accidental self-inoculation or by tick bite. These illnesses are believed to represent infection acquired via the respiratory route. This report emphasizes the aerosol hazard of Rickettsia rickettsii in the laboratory and discusses the possibility of respiratory transmission of Rocky Mountain spotted fever in nature. The illness occurred only in personnel who had received either no vaccination or the primary series of the commercial (Lederie) vaccine against this infection. Other personnel who had received the primary series with multiple booster vaccinations demonstrated increased immunity as measured by humoral antibody titers and rickettsial antigen-induced lymphocyte transformation; no cases of clinical disease developed in these multiply-vaccinated personnel.

Adult↗
PubMed1977

Studies on Theileriidae (Sporozoa) in Tanzania. X. A large-scale field trial on immunization against cattle Theileriosis.

50 cattle immunized by an infection and treatment method with 3 strains of Theileria parva (Mugaga, Kiambu 5 and Serengeti transformed), together with 19 controls, were exposed to natural tick infestation in Tanzania, in a site where a continuous influx of infected ticks from different regions of the country may be expected to occur. Exposure lasted for 2 months, monitoring continued for 3 more weeks after exposure ended. All 19 controls contracted East Coast Fever and died. 40 of the 50 immunized animals survived the whole period of monitoring; the other 10 died of accidents (2), heartwater (3) and unidentified causes (5); none died of ECF. It is recommended that this method of immunization be routinely applied to protect valuable animals at risk. An attempt to immunize against pathogenic Theileria mutans, by injecting blood containing piroplasms of a strain of low pathogenicity, showed that this method may protect against high parasitaemias caused by natural tick-borne infections and may be useful in eliminating the confusing factor of T. mutans in future trials on East Coast Fever.

Animals↗
PubMed1978

Distribution and prevalence of spotted fever group rickettsiae in ticks from South Carolina, with an epidemiological survey of persons bitten by infected ticks.

Live ticks removed from human hosts were tested for the presence of spotted fever group rickettsiae from 1974 through 1976. Spotted fever group rickettsiae were detected in Dermacentor variabilis, Amblyomma americanum, Amblyomma maculatum, and Ixodes scapularis. Persons from whom positive ticks were removed in 1974 and 1975 were questioned about ensuing illness. Eleven of 51 persons from whom rickettsia-positive D. variabilis were removed reported some unexplained combination of symptoms compatible with Rocky Mountain spotted fever. Persons with positive ticks other than D. variabilis reported no illness in the 2 weeks following exposure. D. variabilis from the Coastal Plain of South Carolina have a higher percentage of infection than those from the Piedmont region. Conversely, most reported human cases of spotted fever are from the Piedmont.

Arachnid Vectors↗
PubMed1975

Tick-borne viruses associated with seabirds in North America and related islands.

About 18 tickborne viruses associated with seabirds are known from Canada, Mexico, the Antilles, and the United States, including its oceanic islands. Antigenic groups to which these viruses belong are Hughes, B, Sakhalin, Uukuniemi, Kemerovo, Nyamani and Quaranfil. Members of the last two groups are known in the Western Hemisphere only from Central Pacific Islands and may reflect intrusion of elements of the Australian Region. In the areas under discussion, antibody surveys have been minimal, but there is some indication of human exposure to agents of the Kemerovo group. Members of the Hughes, Nyamanini, and Quaranfil groups are all argasid tick viruses, largely tropical or subtropical in distribution, and associated particularly with gulls and terns (Laridae). The remainder, with the exception of Mono Lake (Kemerovo group, Chenuda Subgroup), which may be a virus of inland birds, are ixodid tick viruses associated mostly with seabirds of the polar or subpolar regions. All of these viruses are seen as acted upon by a common pattern of geographic and biotic factors that influences antigenic diversity of the virus and favors development of strong insular variants.

Animals↗
PubMed1977

Studies on Theileriidae (Sporozoa) in Tanzania. VI. Second field trial on immunization against cattle theileriosis.

Nine cattle, immunized by an infection and treatment method with 3 strains of Theileria parva (Muguga, Kiambu 5 and Serengeti transformed) and nine controls, were exposed to natural tick infestation in Tanzania. All controls contracted fatal East Coast Fever within 2 months of exposure. All immunized animals survived the period of exposure (over 2 months), but later one died of ECF, one of heart-water, one of an undetermined cause (not a theileriosis), and one disappeared from the herd. The 5 remaining animals survived for over 3 months after exposure ended. It is thought that this method of immunization is of value in protecting valuable animals at risk. An attempt to immunize against pathogenic Theilereia mutans, by injecting blood containing an apathogenic strain of this parasite, gave inconclusive results as no pathogenic strains were encountered during the trial.

Animals↗
PubMed1979

Prevalence of parasitism by Amblyomma americanum on wild turkey poults as influenced by prescribed burning.

Captive-raised eastern wild turkey (Meleagris gallopavo silvestris) poults were allowed to forage on either recently burned plots or on plots that had not been burned during the previous 3 years. Following a two hour exposure on the study plots, external parasites were recovered from all poults. The louse (Menacanthus stramineus) and the lone star tick (Amblyomma americanum) were the only parasites recovered. Fifty-nine poults exposed to the burned plots had a significantly (P less than 0.001) lower prevalence of A. americanum infestation than did 57 poults exposed to the unbured plots. Thirty-five percent of the poults exposed to the unburned plots were infested by A. americanum. A single A. americanum was recovered from one poult exposed to burned plots.

Animals↗
PubMed1977

Bovine anaplasmosis transmission studies conducted under controlled natural exposure in a Dermacentor andersoni = (venustus) indigenous area of eastern Oregon.

In Anaplasma marginale transmission studies conducted on the high semi-arid range of eastern Oregon during the 1974 and 1975 vector season, A marginale-susceptible calves (principals) were maintained on 2 raised tick-proof platforms. Anaplasmosis-susceptible control calves of approximately the same age and latent-infected cows grazed the area surrounding the platforms. One latent-infected steer spent the entire 1975 vector season on a platform with the principals. The 28 principals did not develop anaplasmosis, whereas 15 of 30 (50%) controls became infected. The disease was not transmitted from the latent-infected cattle to the principals exposed only to flying hematophagous insects, whereas 50% of the controls exposed to the Rocky Mountain wood tick Dermacentor andersoni) = (venustus) developed the disease. Dermacentor andersoni appears to be the principal vector on this range.

Anaplasmosis↗