Sensitivity of the kidney cells primary culture of Hilgendorf's tube-nose bat to infection by different genetic variants of SARS-CoV-2 (Coronaviridae: Betacoronavirus)

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Introduction

The family Coronaviridae is the only one of the 14 families in the order Nidovirales that contains species pathogenic to humans. Of the 6 human coronaviruses (Nidovirales: Coronaviridae) known to date [1], two betacoronaviruses (Betacoronavirus) are considered particularly dangerous: Betacoronavirus pandemicum, including SARS-CoV-2 (Sarbecovirus subgenus) [2, 3], and Betacoronavirus cameli (Merbecovirus subgenus) [3].

B. cameli, discovered in 2012, is associated with the development of an epidemic on the Arabian Peninsula and numerous imported cases worldwide [4, 5], the most well-known of which was the outbreak in the Republic of Korea [6]. SARS-CoV-2 (B. pandemicum) caused the first coronavirus-related pandemic in human history, COVID-19 [3, 7].

According to the results of ecological and virological monitoring, the natural reservoir of all known human coronaviruses, including SARS-CoV-2, is bats [3, 8]–an order (Chiroptera) of mammals possessing a number of unique evolutionary adaptations for active flight and echolocation [8, 9]. Currently, 29 (27 in binary nomenclature) viruses of the family Coronaviridae are known to have been isolated from bats: 19 of them belong to the genus Alphacoronavirus and 10 to genus Betacoronavirus [9]. After crossing the interspecies barrier in 2019–likely using pangolins as an intermediate host [1]–SARS-CoV-2 entered the human population and began to mutate rapidly to evade herd immunity (resulting from natural infection and vaccination efforts) [10, 11]. This process continues in the post-pandemic period, requiring epidemiological, virological, and molecular-genetic monitoring of the SARS-CoV-2 virus [4, 5].

Over the past decade, various cellular models derived from the tissues and organs of bats, particularly cell cultures, have been established and are widely used. The authors of numerous studies believe that bat cell cultures are valuable tools for investigating the evolutionary links between bats and coronaviruses. For the purpose of studying cellular tropism, which helps determine the host range and possible origin of zoonotic viruses, diploid bat cell cultures are particularly highlighted, characterized by uniform cytomorphological characteristics and a stable karyotype [12–16].

Another equally important application of such cultures is the study of immunological aspects [17, 18] and the molecular mechanisms underlying bats' resistance to viral infections [14, 19, 20].

The aim of this study is to investigate the susceptibility of primary kidney cell cultures from the Siberian tube-nosed bat (Murina hilgendorfi) to infection with SARS-CoV-2 strains of different genotypes.

Materials and methods

Ethical considerations. The authors confirm compliance with institutional and national standards for the use of laboratory animals in accordance with the Consensus Author Guidelines for Animal Use (IAVES, July 23, 2010). The study protocol was approved by the Ethics Committee of the G.P. Somov Research Institute of Epidemiology and Microbiology of Rospotrebnadzor (Protocol No. 2 dated November 16, 2021).

Field data collection. Two male Siberian long-nosed bats, M. hilgendorfi (Chiroptera: Vespertilionidae), were captured using a mist net at the foot of Lesnaya Hill in the floodplain of the Lesnaya Stream (Primorsky Krai, Khasansky District, near the village of Ovchinnikovo) in the first half of August 2025. The species was identified based on morphological characteristics [21, 22]. The search for and removal of ectoparasites [21, 23] were conducted in the field: a wingless blood-sucking fly, Nycteribia quasiocellata (Diptera: Nycteribiidae)¹, was found on one individual. Bats were transported to the laboratory in individual canvas bags lined with dry grass, in a car refrigerator at a temperature of +12 °C.

Isolation of primary kidney cell cultures from M. hilgendorfi bats. Upon arrival at the laboratory, the bats were euthanized by intraperitoneal injection of 70% ethyl alcohol (200 μL) followed by cervical dislocation. During a complete postmortem examination [22], a search for endoparasites [24] was conducted (none detected). A pool of internal organs and feces was used to screen for infectious agents (see below).

The kidneys were removed and placed in containers with saline solution (SS) containing 10,000 units/mL of penicillin, 10,000 μg/mL of streptomycin, and 25 μg/mL of amphotericin (Gibco, USA). Using magnifying glasses, the cortical layer tissues of the kidneys were separated, mechanically minced into fragments approximately 2–3 mm³ in size, washed three times with SS to remove blood, and performed standard tissue trypsinization in a solution of 0.25% trypsin (Servicebio, China) and 0.02% Versene (Biolot, Russia) in a 1 : 1 ratio at 37 °C on a shaker. After centrifuging three times at 500 rpm × 10 min in a centrifuge, 5% fetal bovine serum (FBS) (Biolot, Russia) was added to the resulting cell suspension to neutralize the trypsin. The cell pellet was resuspended and transferred to 25-mL flasks (Nest, China) containing DMEM growth medium (BioinnLabs, Russia) supplemented with 10% ETS (Biolot, Russia) and an antibiotic/antifungal agent (Gibco, USA). The seeding concentration was 3 × 10⁵ cells/mL. The cells were cultured at 37 °C and 5% CO₂. Subsequent passages of the cell culture were performed with a passage ratio of 1 : 2. Upon reaching a monolayer after the 5th passage, the cell suspension was transferred to 24-well plates (Jet Bio Filtration, China) and incubated until a monolayer formed.

Detection of viruses in the internal organs and fecal samples of donors. Bats serve as a natural reservoir for a large number of viruses [3], among which lyssaviruses (Mononegavirales: Rhabdoviridae, Lyssavirus) [25, 26] and coronaviruses [3, 8] are of particular relevance to the southern Russian Far East.

Molecular genetic detection of these viruses was performed using real-time reverse transcription polymerase chain reaction (RT-qPCR), employing both commercial test systems such as AmpliSens RABV (Central Research Institute of Epidemiology, Russia), RT-qPCR-SARS-CoV-2 (Syntol, Russia), AmpliSens CoV-Bat (Central Research Institute of Epidemiology, Russia), as well as in-house systems with universal primers [3, 8, 27]. Virus detection via bioassay was performed by intracerebral infection of newborn inbred laboratory mice with a 10% suspension of a pool of internal organs (brain, lung, small intestine) (0.01 mL), prepared in DMEM medium (BioinnLabs, Russia) with gentamicin and filtered, followed by observation of the animals for 3 weeks.

SARS-CoV-2 strains used to infect primary M. hilgendorfi kidney cell cultures: SARS-CoV-2/Russia_Vladivostok/5130/2020 (Wuhan genotype; VGARus ID: prim000098; GenBank ID: OQ363272; GISAID ID: EPI_ISL_16756941), SARS-CoV-2/Russia_Vladivostok/6843/2021 (Delta; prim000021; OQ318410; EPI_ISL_16641839) and SARS-CoV-2/Russia_Vladivostok/P63/2023 (Omicron; prim0002; OR083734; EPI_ISL_17738935; sublineage XBB.1.36) were obtained from the Collection of Pathogenic Microorganisms at the G.P. Somov Research Institute of Epidemiology and Microbiology of Rospotrebnadzor [5, 27].

Inoculation of the primary cell culture (as well as Vero-E6 cells, which were cultured at 37 °C and 5% CO₂ in DMEM medium (BioinnLabs, Russia) supplemented with 10% FCS (Biolot, Russia) and an antibiotic/antifungal agent (Gibco, USA), and then infected in parallel as a control), was carried out by incubating it with the virus at an infectious dose of 2.0 log₁₀ (TCID₅₀)/mL at 37 °C in a CO₂ atmosphere for 1 hour. The cells were then washed three times with phosphate-buffered saline, transferred to 96-well plates with an adhesive coating (Jet Bio Filtration, China), and incubated at 37 °C in a CO₂ atmosphere. On days 2, 4, and 6, cell-free culture supernatant was collected, frozen, and tested simultaneously using the RT-qPCR-SARS-CoV-2 test system (Syntol, Russia) to determine the cycle threshold (C_t). Furthermore, in the course of infection of kidney cell cultures with strains of different SARS-CoV-2 genetic variants, pathomorphological observation was conducted to document the cytopathic effect (CPE) of the virus.

Statistical analysis of the obtained data was performed using Statistica ver. 10.0 (StatSoft, USA). The sample data were characterized using the median (Me) and the minimum and maximum values (min–max). Differences between groups were assessed using the Student's t-test with a significance level for the alternative hypothesis of p ≤ 0.05.

Results

The results of testing for lyssaviruses and coronaviruses in the internal organs and feces of bats using RT-qPCR were negative (cycle threshold values greater than 40). During a 3-week observation period of intracerebrally infected newborn mice, no clinical symptoms of the disease were detected.

Upon culturing bat kidney cells, a heterogeneous monolayer with 70–80% confluence formed by days 6–7. The monolayer consisted of two cell types: fibroblast-like cells–elongated spindle-shaped cells forming bundles oriented in various directions — and epithelium-like cells of polygonal shape, randomly oriented on the culture surface (Fig. 1, a, b). All cells had homogeneous cytoplasm and well-defined borders; no signs of degeneration were observed. Intact cell cultures retained their typical morphology throughout 15 passages. During subculturing, it was noted that after treatment of the cell monolayer with a 1 : 3 mixture of trypsin and Versene, fibroblast-like cells detached first, while longer exposure to the trypsin-Versene solution was required to detach the epithelium-like cells.

 

Fig. 1. Intact bat kidney cell culture.

a – on the 6th day; b – on the 15th day of cultivation. ×100.

Рис. 1. Интактная культура клеток почек летучих мышей.

а – 6-е сутки; б – 15-е сутки культивирования. Увеличение 100.

 

Following infection of bat kidney cell cultures with strains of different SARS-CoV-2 genetic variants, the virus's cytopathic effect became apparent as early as the initial stages. For example, when the culture was infected with the Delta strain, by day 2 the monolayer density had significantly decreased, isolated clusters of cells formed, epitheliocyte-like cells became rounded, and vacuolization and cytoplasmic granularity were observed in fibroblast-like cells. By day 6, signs of cell culture degradation were noted–a large number of detached symplasts and individual dead cells (Fig. 2, a, b).

 

Fig. 2. Cytopathic effect of the SARS-CoV-2 virus strain Delta in bat kidney cell culture.

a – on the 2nd day; b – on the 6th day after infection. ×100.

Рис. 2. Цитопатическое действие вируса SARS-CoV-2 штамм Delta в культуре клеток почек летучих мышей.

а – на 2-е сутки; б – на 6-е сутки после заражения. Увеличение 100.

 

Following exposure of the test culture to the Omicron strain of the SARS-CoV-2 virus, symplast formation was observed as early as day 2, and the monolayer consisted predominantly of fibroblast-like cells that elongated to the point of becoming filamentous. By day 6, thinning of the monolayer was accompanied by cell fragmentation and lysis, resulting in the formation of large conglomerates of dead cells (Fig. 3, a, b).

 

Fig. 3. Cytopathic effect of the SARS-CoV-2 virus strain Omicron in bat kidney cell culture.

a – on the 2nd day; b – on the 6th day after infection. ×100.

Рис. 3. Цитопатическое действие вируса SARS-CoV-2 штамм Omicron в культуре клеток почек летучих мышей.

а – на 2-е сутки; б – на 6-е сутки после заражения. Увеличение 100.

 

Following infection of bat kidney cell cultures with the Wuhan strain of SARS-CoV-2, on day 2, the detachment of rounded infected cells from the surface of the culture flask was accompanied by thinning of the monolayer. On day 6, the detaching, chaotically arranged, thread-like fibroblast-like cells formed a sparse, loose monolayer. Cellular debris consisting of fragments of destroyed cells was visualized on the culture surface (Fig. 4, a, b).

 

Fig. 4. Cytopathic effect of the SARS-CoV-2 virus strain Wuhan in bat kidney cell culture.

a – 2nd day; b – on the 6th day after infection. х100

Рис. 4. Цитопатическое действие вируса SARS-CoV-2 штамм Wuhan в культуре клеток почек летучих мышей.

а – на 2-е сутки; б – на 6-сутки после заражения. Увеличение 100.

 

Thus, different strains of the SARS-CoV-2 virus exert a cytopathic effect on bat kidney cell cultures, differing in the mechanism of their destructive impact on the cells.

SARS-CoV-2 RNA was detected in the supernatant of bat kidney cell lysates on day 2 after infection with the Wuhan, Delta, and Omicron SARS-CoV-2 variants. By day 6, C_t values in RT-qPCR had significantly decreased compared to day 2 for all three strains, indicating coronavirus replication in bat kidney cells. According to the results of RT-qPCR analysis, the C_t values of the SARS-CoV-2 Wuhan, Delta, and Omicron variants on bat kidney cells did not differ statistically significantly from one another, and the dynamics of their decline were similar (Table).

 

Table. Dynamics of replication of different SARS-CoV-2 genetic variants in M. hilgendorfi bat kidney cells (BKС) and in Vero-E6 cells

Таблица. Динамика репликации разных геновариантов SARS-CoV-2 в клетках почек летучих мышей M. hilgendorfi (КПЛМ) и в клетках Vero-Е6

SARS-CoV-2 strain Геновариант штамма SARS-CoV-2	Threshold cycle in RT-qPCR (Ct) Пороговый цикл в ОТ-ПЦР (Ct) Period after infection (day) Срок после заражения (сут)
	2-е		4-е		6-е
	bat kidney cells КПЛМ	Vero-Е6	bat kidney cells КПЛМ	Vero-Е6	bat kidney cells КПЛМ	Vero-Е6
Wuhan	32 (25–34)	16# (11–19)	26 (21–29)	12# (11–15)	20* (17–24)	11# (6–14)
Delta	29 (24–32)	19 (14–24)	25 (20–26)	15 (12–17)	21* (18–22)	12# (11–15)
Omicron	32 (30–36)	21 (19–24)	27 (23–31)	19 (16–20)	25* (21–28)	16 (13–19)

Note. Data are presented as the median (Me) and the minimum and maximum values (min–max) from three independent experiments. C_t – cycle threshold. * – statistically significant (p ≤ 0.05) differences for the SARS-CoV-2 genetic variants Wuhan, Delta, and Omicron genotypes on day 6 compared to day 2 when cultured on bat kidney cells; ^# – statistically significant (p ≤ 0.05) differences for the SARS-CoV-2 Wuhan and Delta genotypes compared to Omicron when cultured on Vero-E6.

Примечание. Данные представлены в виде медианы (Me) и минимального и максимального значения (min–max) в трех независимых экспериментах. C_t – пороговый цикл. * – статистически значимые (р ≤ 0,05) различия для генотипов SARS-CoV-2 Wuhan, Delta и Omicron на 6-е сутки по сравнению со 2-ми сутками при культивировании на КПЛМ; ^# – статистически значимые (р ≤ 0,05) различия для генотипов SARS-CoV-2 Wuhan и Delta по сравнению с Omicron при культивировании на Vero-Е6.

 

It should be noted that the C_t values for the SARS-CoV-2 Wuhan, Delta, and Omicron genetic variants cultured on Vero-E6 cells were significantly lower compared to bat kidney cells, and the Wuhan and Delta strains replicated more actively than the Omicron strains (p ≤ 0.05) (Table).

Discussion

The pandemic and the ongoing spread of coronavirus infection have spurred increased research into the establishment of new cell lines derived from various bat tissue types. There is a growing body of work dedicated to studying the tropism of coronaviruses toward cell cultures from different bat species. For example, MERS-CoV has been found to exhibit broad species tropism: the virus replicated in cell lines from three bat families (lungs of Miotis ricketti, kidneys of Pipistrellus abramus, kidneys and lungs of Rhinolophus sinicus, and kidneys of R. leschenaultia) [16]. SARS-CoV replicated only in R. sinicus cells, while HCoV-229E did not replicate in any of the cell cultures derived from the bats studied. The authors explain this by noting that bats are the primary source of SARS-CoV, human coronavirus 229E (HCoV-229E), and, likely, MERS-CoV [16].

It was also shown that SARS-CoV is capable of replicating effectively in R. sinicus kidney cells, whereas SARS-CoV-2 did not possess this ability. According to the authors, one possible reason is that SARS-CoV-2 has limited tropism for this bat species, which may indicate a different evolutionary origin for SARS-CoV-2, and R. sinicus bats were unlikely to have been its direct carriers [15]. At the same time, intestinal organoids from R. sinicus horseshoe bats were susceptible to SARS-CoV-2 infection and supported active viral replication [28].

S. Lau et al. observed the absence of SARS-CoV and SARS-CoV-2 replication in 13 primary and immortalized cell lines from six different bat species, including a kidney cell culture from the Miniopterus pusillus bat species [29], while S. Aicher et al. also observed this in immortalized cell lines derived from brain, lung, nasal, wing, and kidney tissues of various bat species of the Rhinolophus and Myotis genera [13]. The latter study showed that none of the numerous cell lines obtained supported SARS-CoV-2 replication, not even R. ferrumequinum cells, isolated from bats belonging to the same genus as the BANAL-52 bats, which are natural carriers of alpha- and beta-coronaviruses, potential ancestors of SARS-CoV-2 [13]. However, susceptibility to SARS-CoV-2, including clinical isolates, was subsequently demonstrated, as well as the virus's ability to persist in a spontaneously immortalized cell line derived from the kidneys of the Blyth's horseshoe bat (R. lepidus) [30]. This indicates a possible relationship between the virus and the host, although compared to Vero-E6 cells, SARS-CoV-2 replication in these cells was slowed, as evidenced by higher RT-PCR cycle thresholds at later stages of viral culture and smaller CPE foci. A possible reason for this is that bat cells possess a unique antiviral mechanism that prevents SARS-CoV-2 from taking control of them [18, 31].

The authors of a recent study investigated the mechanisms by which the coronavirus enters cells [20]. Using genetic methods, a recombinant strain of EjCoV-3 (Eptesicus japonensis CoV-3) was obtained, and it was found to replicate efficiently in human respiratory and intestinal cell cultures without utilizing the cell entry receptors ACE2 and DPP4 (dipeptidyl peptidase-4). EjCoV-3 turned out to be the first bat merbecovirus capable of effectively replicating in human respiratory cells. According to the authors, these results offer a new perspective on the ability of MERS-related coronaviruses to enter the human respiratory tract independently of ACE2 and DPP4, and provide an answer to the question of whether the bat-derived (merbecovirus) EjCoV-3, discovered in Japan, can infect humans, and also contribute to the study of the likelihood of new outbreaks of coronavirus infection.

Despite the expansion of research in recent years, there remains a clear need to develop additional cell lines derived from the cells and tissues of various bat species. Bat cell lines contribute to our understanding of the growing role of bat-borne viruses in the emergence of new viral diseases, a trend observed in recent decades.

Given the literature data showing that ACE2 is highly expressed in the kidney cells of several bat species [13, 14], this study utilized kidneys from M. hilgendorfi as a cell source to investigate the susceptibility of primary Siberian long-nosed bat kidney cell cultures to infection by SARS-CoV-2 strains of different genetic variants. The resulting cell culture consisted of fibroblast-like and epithelial-like cells. The efficiency of coronavirus replication in bat kidney cell cultures and Vero-E6 cells was assessed by the presence of CPE and viral RNA using RT-qPCR.

Cytopathic effects, as judged by morphological changes in bat kidney cells infected with strains of different SARS-CoV-2 genotypes, were already evident on day 2, and by day 6, signs of cell culture degradation intensified.

The cycle threshold values (C_t) in RT-qPCR decreased significantly from day 2 to day 6 post-infection, indicating an increase in viral RNA content and, consequently, that the SARS-CoV-2 strains under study (Wuhan-like genotype, Delta and Omicron genetic variants) are capable of actively replicating in M. hilgendorfi bat kidney cell culture. No statistically significant differences in the replicative capacity of the studied genotypes were detected. An increase in viral RNA content over time was detected in the Vero-E6 cell culture used as a control; however, the studied coronavirus strains replicated much more actively in this cell culture.

The replication of coronaviruses in bat cells indicates the possibility of virus carriage by members of this species, as well as their potential involvement in the epidemic process as virus vectors. This, in turn, suggests a role for bats in the formation of natural reservoirs of coronavirus infection. Furthermore, it can be assumed that the prolonged circulation of SARS-CoV-2 in the human population, the decrease in pathogenicity, and the increase in transmissibility to humans did not affect the ability of the virus to replicate in bat cells.

However, based on a number of studies [13, 14, 18, 31], it can be assumed that the results obtained in this study, which indicate the ability of SARS-CoV-2 (Wuhan-like, Delta and Omicron genetic variants) to replicate in M. hilgendorfi bat kidney cell culture, require further investigation. In particular, it is necessary to assess the virus's infectious activity in cell culture at different time points after infection.

The answer to the question of why bats can be carriers of a viral infection without visible signs of disease lies in the constant, evolutionarily developed activity of the interferon system and other mechanisms that provide a powerful antiviral immune response in bats against RNA viruses [32]. In particular, when assessing the activity level of the innate immune system, it was found that in the absence of immune stimulation, background expression of interferon-β was observed in the MdbK3-14 cell line derived from the kidneys of M. sibiricus (Kastschenko, 1905) bats [33]. This is likely related to the inability of cell cultures from several bat species to produce an infectious virus.

Conclusion

1. For the first time, a primary cell culture of kidneys from M. hilgendorfi bats inhabiting the southern part of Russia's Primorsky Krai has been established; this culture is recommended for virological research.
2. The obtained M. hilgendorfi bat kidney cell culture is sensitive to SARS-CoV-2 strains, supporting active replication of the Wuhan, Delta, and Omicron genetic variants, as confirmed by ELISA and RT-qPCR.
3. According to the results of RT-qPCR analysis, the differences between the Wuhan, Delta, and Omicron genetic variants are not statistically significant.

¹ This is the first record of N. quasiocellata on M. hilgendorfi in Russia; previously, N. quasiocellata had been found either on other Far Eastern species or on M. hilgendorfi outside the Far East [23, 24].

About the authors

Tatyana A. Kuznetsova

G.P. Somov Institute of Epidemiology and Microbiology, Russian Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing; School of Medicine and Life Science, Far Eastern Federal University

Email: takuznets@mail.ru
ORCID iD: 0000-0002-4315-6959

Doct. Sci. (Med.), Main Researcher, Head, Lab. of Immunobiological Preparates

Russian Federation, 690087, Vladivostok; 690922, Vladivostok

Natalia V. Krylova

G.P. Somov Institute of Epidemiology and Microbiology, Russian Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing

Email: krylovanatalya@gmail.com
ORCID iD: 0000-0002-9048-6803

Doct. Sci. (Biol.), Leading Researcher, Head, Lab. of Respiratory Infections

Russian Federation, 690087, Vladivostok

Anastasia A. Mikhalko

G.P. Somov Institute of Epidemiology and Microbiology, Russian Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing; School of Medicine and Life Science, Far Eastern Federal University

Email: nastya.mikhalko@inbox.ru
ORCID iD: 0000-0001-8939-3696

Technician, Lab. of Respiratory Infections; Student of Department of Biotechnology

Russian Federation, 690087, Vladivostok; 690922, Vladivostok

Anna K. Gazha

G.P. Somov Institute of Epidemiology and Microbiology, Russian Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing

Email: angazha@mail.ru
ORCID iD: 0000-0002-2672-1629

Cand. Sci. (Med.), Senior Researcher, Lab. of Immunobiological Preparates

Russian Federation, 690087, Vladivostok

Tatyana P. Smolina

G.P. Somov Institute of Epidemiology and Microbiology, Russian Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing

Email: tsmol@mail.ru
ORCID iD: 0000-0003-4505-3627

Cand. Sci. (Biol.), Leading Researcher, Laboratory of Immunobiological Preparates

Russian Federation, 690087, Vladivostok

Elena I. Drobot

G.P. Somov Institute of Epidemiology and Microbiology, Russian Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing

Email: eidrobot@mail.ru
ORCID iD: 0000-0001-7672-1582

Cand. Sci. (Biol.), Senior Researcher, Pathology Laboratory

Russian Federation, 690087, Vladivostok

Yurii А. Belov

G.P. Somov Institute of Epidemiology and Microbiology, Russian Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing; School of Medicine and Life Science, Far Eastern Federal University

Email: belov.ya@dvfu.ru
ORCID iD: 0000-0001-8313-5610

Junior Researcher, Center of Molecular Diagnostics; Lecturer of Department of Epidemiology, Microbiology and Parasitology

Russian Federation, 690087, Vladivostok; 690922, Vladivostok

Egor M. Shchelkanov

State University of Education

Email: egorshchelkanov@mail.ru
ORCID iD: 0000-0003-0202-958X

Student of the Faculty of Natural Sciences

Russian Federation, 141014, Mytishchi

Anatoliy I. Belov

G.P. Somov Institute of Epidemiology and Microbiology, Russian Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing

Email: anatoliybelov62@mail.ru
ORCID iD: 0009-0002-8435-0325

Zoologist of the Field Department

Russian Federation, 690087, Vladivostok

Tatyana V. Tabakaeva

G.P. Somov Institute of Epidemiology and Microbiology, Russian Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing; School of Medicine and Life Science, Far Eastern Federal University

Author for correspondence.
Email: rabchan1992@gmail.com
ORCID iD: 0000-0002-9517-7495

Leading Researcher, Laboratory of Ectoparasitology; Senior Lecturer of Department of Epidemiology, Microbiology and Parasitology

Russian Federation, 690087, Vladivostok; 690922, Vladivostok

Dmitry V. Pankratov

G.P. Somov Institute of Epidemiology and Microbiology, Russian Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing

Email: pankratov_dmitriy@rambler.ru
ORCID iD: 0000-0002-0115-5384

Deputy Director for Field Research

Russian Federation, 690087, Vladivostok

Tatyana S. Zaporozhets

G.P. Somov Institute of Epidemiology and Microbiology, Russian Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing

Email: niiem_vl@mail.ru
ORCID iD: 0000-0002-8879-8496

Doct. Sci. (Med.), Leading Researcher, Lab. of Respiratory Viral Infections

Russian Federation, 690087, Vladivostok

Michail Y. Shchelkanov

G.P. Somov Institute of Epidemiology and Microbiology, Russian Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing; School of Medicine and Life Science, Far Eastern Federal University

Email: adorob@mail.ru
ORCID iD: 0000-0001-8610-7623

Doct. Sci. (Biol.), Corresponding Member of the RAS, Director; Head of the Department of Epidemiology, Microbiology and Parasitology

Russian Federation, 690087, Vladivostok; 690922, Vladivostok

References

Supplementary files