Epidemiology of Taenia saginata taeniosis/cysticercosis: a systematic review of the distribution in central and western Asia and the Caucasus

BackgroundThe zoonotic parasite Taenia saginata transmits between humans, the definitive host (causing taeniosis), and bovines as the intermediate host (causing cysticercosis). Central and western Asia and the Caucasus have large cattle populations and beef consumption is widespread. However, an overview of the extent of human T. saginata infection and bovine cysticercosis is lacking. This review aims to summarize the distribution of T. saginata in this region.MethodsA systematic review was conducted, that gathered published and grey literature, and official data concerning T. saginata taeniosis and bovine cysticercosis in central and western Asia and the Caucasus published between January 1st, 1990 and December 31st, 2018. Where no data were available for a country within this period, published data from 1985-1990 were also accessed.ResultsFrom 10,786 articles initially scanned, we retrieved 98 full-text articles from which data were extracted. In addition, two unpublished datasets were provided on the incidence of human taeniosis. Data for human taeniosis and bovine cysticercosis were found for all countries except Turkmenistan. Human taeniosis prevalence varied from undetected to over 5.3%, with regional variations. Where bovine cysticercosis was detected, prevalences varied from case reports to 25%.ConclusionsThe public health burden of T. saginata is assumed to be small as the parasite is of low pathogenicity to humans. However, this review indicates that infection continues to be widespread and this may result in a large economic burden, due to the resources utilized in meat inspection and condemnation or processing with subsequent downgrading of infected carcasses

Building Scientific Capability and Reducing Biological Threats: The Effect of Three Cooperative Bio-Research Programs in Kazakhstan.

Cooperative research programs aimed at reducing biological threats have increased scientific capabilities and capacities in Kazakhstan. The German Federal Foreign Office's German Biosecurity Programme, the United Kingdom's International Biological Security Programme and the United States Defense Threat Reduction Agency's Biological Threat Reduction Program provide funding for partner countries, like Kazakhstan. The mutual goals of the programs are to reduce biological threats and enhance global health security. Our investigation examined these cooperative research programs, summarizing major impacts they have made, as well as common successes and challenges. By mapping various projects across the three programs, research networks are highlighted which demonstrate best communication practices to share results and reinforce conclusions. Our team performed a survey to collect results from Kazakhstani partner scientists on their experiences that help gain insights into enhancing day-to-day approaches to conducting cooperative scientific research. This analysis will serve as a basis for a capability maturity model as used in industry, and in addition builds synergy for future collaborations that will be essential for quality and sustainment

First Indications of Omsk Haemorrhagic Fever Virus beyond Russia

Omsk haemorrhagic fever virus (OHFV) is the agent leading to Omsk haemorrhagic fever (OHF), a viral disease currently only known in Western Siberia in Russia. The symptoms include fever, headache, nausea, muscle pain, cough and haemorrhages. The transmission cycle of OHFV is complex. Tick bites or contact with infected small mammals are the main source of infection. The Republic of Kazakhstan is adjacent to the endemic areas of OHFV in Russia and febrile diseases with haemorrhages occur throughout the country—often with unclear aetiology. In this study, we examined human cerebrospinal fluid samples of patients with suspected meningitis or meningoencephalitis with unknown origins for the presence of OHFV RNA. Further, reservoir hosts such as rodents and ticks from four Kazakhstan regions were screened for OHFV RNA to clarify if this virus could be the causative agent for many undiagnosed cases of febrile diseases in humans in Kazakhstan. Out of 130 cerebrospinal fluid samples, two patients (1.53%) originating from Almaty city were positive for OHFV RNA. Screening of tick samples revealed positive pools from different areas in the Akmola region. Of the caught rodents, 1.1% out of 621 were positive for OHFV at four trapping areas from the West Kazakhstan region. In this paper, we present a broad investigation of the spread of OHFV in Kazakhstan in human cerebrospinal fluid samples, rodents and ticks. Our study shows for the first time that OHFV can not only be found in the area of Western Siberia in Russia, but can also be detected up to 1.600 km away in the Almaty region in patients and natural foci

Prevalence of Rickettsia species in ticks including identification of unknown species in two regions in Kazakhstan

Abstract Background Over 60 years ago clinical patterns resembling tick-borne rickettsioses have been described for the first time in Kazakhstan. Since 1995 the incidence of clinical cases of tick-borne rickettsioses in humans seems to be rising but studies on epidemiological data regarding the occurring etiological agents, tick vector species, prevalence and distribution throughout Kazakhstan are still scarce to date. The aim of the study was molecular investigation of ticks for spotted-fever group rickettsiae in the endemic Kyzylorda region and the so far considered as non-endemic Almaty region. A total of 2341 ticks was collected in the two regions in Kazakhstan and sorted in 501 pools: Ixodes persulcatus (243); Dermacentor marginatus (129); Haemaphysalis punctata (104); Hyalomma asiaticum (17); Dermacentor reticulatus (3); and Rhipicephalus turanicus (5). Pools were tested for Rickettsia spp. using real-time PCR. For positive samples multilocus sequence typing (MLST) was performed. Results The calculated minimum infection rate (MIR) for rickettsiae in the investigated ticks in Almaty region varied between 0.4–15.1% and 12.6–22.7% in the Kyzylorda region. At least four different Rickettsia species were identified in the two selected regions of Kazakhstan. Two of these are already known to science: Rickettsia raoultii and R. slovaca, the latter being reported for the first time in Almaty region One new form, “Candidatus R. yenbekshikazakhensis”, was described by MLST of six gene fragments in Almaty region and one new genotype, “genotype R. talgarensis” was detected using three gene fragments. Conclusions Kazakh physicians should be aware of rickettsioses after tick bites in both regions studied. Both, R. raoultii and R. slovaca should be included in the diagnostics. The role for human diseases has further to be investigated for the newly described rickettsiae, “Candidatus R. yenbekshikazakhensis” and “Genotype R. talgarensis”

Seroepidemiological and molecular investigations of infections with Crimean–Congo haemorrhagic fever virus in Kazakhstan

Objectives: The aim of this study was to detect the seroprevalence of Crimean–Congo haemorrhagic fever virus (CCHFV) in patients with fever of unknown origin (FUO) in endemic (Kyzylorda) and non-endemic (Almaty) oblasts of Kazakhstan. Methods: Paired serum samples from 802 patients with FUO were collected. Serum samples were investigated by ELISA to detect IgG and IgM antibodies against CCHFV. Sera with suspected acute infection were further investigated by RT-PCR to detect the viral RNA. Results: IgG antibodies were detected in 12.7% of the sera from both oblasts. Acute infection was shown by IgM ELISA in four patients from Kyzylorda, with only one developing severe CCHF. Viral RNA was found by RT-PCR in the other three patients’ sera. Phylogenetic analysis of partial L and S segments revealed CCHFV genotype Asia 2 and a possible reassortment between the genotypes Asia 1/Asia 2. Animal husbandry, such as working with cattle and horses, was significantly associated with CCHFV seropositivity. Conclusions: The antibodies and viral RNA detected in sera indicate that mild or even asymptomatic CCHFV infections are presented in Kazakhstan. This study describes the circulation of CCHFV in the so far non-endemic Almaty oblast for the first time. In conclusion, physicians treating patients with FUO in Kazakhstan should be aware of mild CCHF. Keywords: Crimean–Congo haemorrhagic fever virus, Fever of unknown origin, Reassortment, Kazakhsta

Molecular and seroepidemiological investigation of Сoxiella burnetii and spotted fever group rickettsiae in the southern region of Kazakhstan

Ticks are involved in the circulation of a number of human pathogens, including spotted fever group (SFG) Rickettsia spp. and Coxiella burnetii. Little is known about the occurrence of these microorganisms in the southern region of Kazakhstan. In 2018–2022, a total of 726 ticks were collected from bitten humans, livestock, and vegetation in four oblasts of the southern region of Kazakhstan and subjected to DNA extraction. The overall infection rate of Coxiella spp. and Rickettsia spp. in the ticks was 3.3% (24/726) and 69.9% (300/429), respectively. Phylogenetic analysis of ompA and gltA genes revealed the presence of three pathogenic SFG rickettsiae: Candidatus R. tarasevichiae, R. aeschlimannii and R. raoultii in ticks collected from bitten humans. In addition, Candidatus R. barbariae was detected in six Rhipicephalus turanicus ticks for the first time in Kazakhstan. To determine the seroprevalence of C. burnetii infection, we performed a serological analysis of samples collected from 656 domestic ruminants (cattle, sheep, and goats) in the region. Overall, 23.5% (154/656) of the animals tested were positive for IgG against C. burnetii. Seroprevalence at the herd level was 54% (28/52). Goats (43%; 12/28; odds ratio (OD) = 28.9, p < 0.05) and sheep (31.9%; 137/430; OD = 18.1, p < 0.05) had higher seroprevalence than cattle (2.5%; 5/198). Among the risk factors considered in this study, age (p = 0.003) and the oblast in which the animals were sampled (p = 0.049) were statistically associated with seropostivity for Q fever in sheep, according to the results of multivariate logistic regression analysis. Seroprevalence ranged from 0% to 55.5% in animals in different districts of the southern region of Kazakhstan. Active C. burnetii bacteremia was detected in four of 154 (2.6%) seropositive animals. The data obtained provide strong evidence of the presence of pathogenic rickettsiae and C. burnetii in the southern region of Kazakhstan and emphasize the need to improve epidemiological surveillance in the region

Vectors, molecular epidemiology and phylogeny of TBEV in Kazakhstan and central Asia

BACKGROUND: In the South of Kazakhstan, Almaty Oblastʼ (region) is endemic for tick-borne encephalitis, with 0.16–0.32 cases/100,000 population between 2016–2018. The purpose of this study was to determine the prevalence and circulating subtypes of tick-borne encephalitis virus (TBEV) in Almaty Oblastʼ and Kyzylorda Oblastʼ. METHODS: In 2015 we investigated 2341 ticks from 7 sampling sites for the presence of TBEV. Ticks were pooled in 501 pools and isolated RNA was tested for the presence of TBEV by RT-qPCR. For the positive samples, the E gene was amplified, sequenced and a phylogenetic analysis was carried out. RESULTS: A total of 48 pools were TBEV-positive by the RT-qPCR. TBEV-positive ticks were only detected in three districts of Almaty Oblastʼ and not in Kyzylorda Oblastʼ. The positive TBEV pools were found within Ixodes persulcatus, Haemaphysalis punctata and Dermacentor marginatus. These tick species prevailed only in Almaty Oblastʼ whereas in Kyzylorda Oblastʼ Hyalomma asiaticum and D. marginatus are endemic. The minimum infection rates (MIR) in the sampling sites were 4.4% in Talgar, 2.8% in Tekeli and 1.1% in Yenbekshikazakh, respectively. The phylogenetic analysis of the generated sequences indicates that TBEV strains found in Almaty Oblastʼ clusters in the Siberian subtype within two different clades. CONCLUSIONS: We provided new data about the TBEV MIR in ticks in Almaty Oblastʼ and showed that TBEV clusters in the Siberian Subtype in two different clusters at the nucleotide level. These results indicate that there are different influences on the circulating TBEV strains in south-eastern Kazakhstan. These influences might be caused by different routes of the virus spread in ticks which might bring different genetic TBEV lineages to Kazakhstan. The new data about the virus distribution and vectors provided here will contribute to an improvement of monitoring of tick-borne infections and timely anti-epidemic measures in Kazakhstan