Current data on the circulation of the Q fever pathogen in the Republic of Guinea

Full Text

Introduction

Q fever or coxiellosis is a common natural focal disease for humans and animals, the etiological agent of which is the bacteria Coxiella burnetii (family Legionellaceae, class Gammaproteobacteria), characterized by polymorphism of the clinical picture in humans and various mechanisms of transmission of the pathogen. In natural foci, the main vector of C. burnetii is considered to be ixodes, less frequently argas ticks, and the reservoir — wild mammals, among farm animals — small and large cattle [1, 2].

The disease in humans runs in the form of fever with general toxic symptoms with possible transition to a chronic form. Due to the widespread infection, a variety of transmission routes (contact, food, airborne and dust), Q fever is an important medical and social problem worldwide.

Furthermore, this infectious disease has an important veterinary significance, as it causes reproductive disorders (abortions and stillbirths) in small and large cattle, which causes significant economic losses, especially in those regions where livestock breeding is the main branch of agricultural production [2].

Coxiellosis is one of the best-studied zoonoses within Africa. There is emerging evidence that C. burnetii infection is responsible for non-malarial febrile illnesses and community-acquired pneumonia in many African countries. However, current information on the incidence of Q fever and circulation of C. burnetii in this continent is limited and heterogeneous [3].

Available publications on previous studies indicate a fairly high level of detection of specific antibodies to the pathogen in the population of some African countries [4–9]. For example, the study of blood serum samples from residents of some settlements of the Sin-Saloum region (Republic of Senegal) showed that specific antibodies to C. burnetii were detected in 3.7–24.8% of samples (depending on the place of residence of the subjects) [5]. Similar data were obtained during serosurvey in pastoralist communities in Marsabit County, northern Kena, when positive results were obtained in 13.2% of cases [6]. Males in Kenya were significantly more likely than females to have immunologic markers identified [7].

It has been shown that pastoralist tribes are at the highest risk of contracting coxiellosis because of their nomadic lifestyle and well-preserved traditions, which increase the likelihood of eating unboiled dairy products and raw meat from infected animals. It is also possible that infection occurs through contact with urine, feces, and blood of infected animals, as well as amniotic fluid after abortion or premature birth [6–9].

It is also known that Q fever causes significant losses among not only farm animals but also wild animals such as antelopes, giraffes, lions and cheetahs, causing irreparable damage to the numbers of these rare mammals [10].

This infectious disease is also becoming relevant as a “travelers' disease” due to the popularization of the African continent and rapidly developing tourism in this territory. An outbreak of Q fever was described in the literature, when during a safari in a natural park in Kenya, 4 (8%) out of 50 participants of the tourist route were infected, which caused importation of cases to Europe [11].

Most of the information published in the open press on the circulation of the Q fever pathogen relates to East Africa. There is much less information on the situation in the western part of the continent. There are data on studies conducted in natural foci of coxiellosis in Ghana, Nigeria, Mali [12–14], as well as in Senegal, where in 2023 two new genotypes of C. burnetii were identified in samples from small mammals, the pathogenicity of which remains to be studied [15].

The Republic of Guinea is located in West Africa, on the coast of the Atlantic Ocean. The population of the country, as of the end of March 2024, is about 14.5 million people [16]. Based on geographical and natural-climatic features, the territory of the state is conditionally divided into 4 landscape-geographical zones: Lower (Maritime), Middle, Upper and Forested (Figure) [17].

 

Landscape and geographical zones of the Republic of Guinea, where markers of the Q fever pathogen were identified.

1 — DNA in blood sera of cattle; 2 — IgG antibodies in blood sera of cattle; 3 — IgG antibodies in blood sera of residents; 4 — DNA in suspensions of bat organs; 5 — antigens in suspensions of bat organs; 6 — cases of human disease; 7 — DNA in suspensions of ixodes ticks; 8 — antigens in suspensions of ixodes ticks; 9 — DNA in suspensions of organs of small mammals; 10 — antigens in suspensions of organs of small mammals.

 

In 1980–1990, the Soviet-Guinean Research Virology and Microbiology Laboratory conducted a large number of studies to investigate the spread of the Q fever pathogen in the Republic of Guinea, including data on the immunity of the country's population and the detection of specific antibodies in the blood sera of farm animals [18]. In the following decades, due to the prevailing economic and political conditions, research was suspended, and the significance of Q fever in the overall morbidity has not been determined. In 2017, as part of the research work of the Russian-Guinean Center for Epidemiology and Prevention of Infectious Diseases (hereinafter referred to as the Center), established on the basis of orders of the Government of the Russian Federation on the premises of the Institute of Applied Biology of Guinea (Kindia), research was continued [19–21].

The aim of the study was to obtain up-to-date data on the distribution of C. burnetii and the features of natural foci of Q fever in different landscape and geographical zones of Guinea.

Materials and methods

Collection of samples of clinical and biological material and subsequent diagnostic work was carried out on the basis of the Center's laboratory by Russian and Guinean specialists, guided by the requirements of sanitary rules and regulations 3.3686-21 “Sanitary and Epidemiological Requirements for the Prevention of Infectious Diseases”.

Human blood serum

Blood serum of practically healthy people was collected in regional hospitals in Guinea and by local specialists. Fasting blood sampling was performed in the morning hours from the ulnar vein in the amount of 5–10 ml into a disposable sterile vacuum tube with a clot activator in compliance with the rules of asepsis.

Then the obtained samples were delivered to the laboratory of the Center in compliance with the rules of biological safety and temperature regime. All serum samples were preliminarily analyzed by immunochromatographic analysis for detection of malaria plasmodium antigens with the SDBIOLINE Malaria Ag P.f./Pan reagent kit (Standart Diagnostics, Inc.). To exclude the possibility of nonspecific reactions, samples containing antigens of malaria pathogens were not included in subsequent studies.

A panel of 3156 sera from virtually healthy individuals living in all 4 landscape-geographic zones of Guinea was compiled to study the herd immunity to the Q fever pathogen in the Guinean population. Different age groups were included: 1519 (48.2%) women and 1637 (51.8%) men. The work was carried out using the enzyme-linked immunosorbent assay (ELISA) reagent kit “Enzyme-linked immunosorbent assay for detection of class G antibodies to C. burnetii antigens” (Pasteur Research Institute of Epidemiology and Microbiology, Russia). The sera were tested at a dilution of 1 : 100.

To clarify the possibility of human disease with Q fever, 332 sera from febrile patients who sought medical help in regional hospitals in Guinea with complaints of prolonged fever and other symptoms not excluding coxiellosis were collected and examined. The material was also collected by Guinean specialists using the methodology described above. For molecular genetic studies, blood was also collected in an amount of 5–10 ml in a disposable sterile vacuum tube with 3.8% sodium citrate.

Samples were examined by polymerase chain reaction (PCR) to detect C. burnetii DNA with the AmpliSens Coxiella burnetii-FL reagent kit (Central Research Institute of Epidemiology, Russia) and ELISA using the diagnostic kit Coxiella burnetii ELISA IgM (Vircell) to detect IgM antibodies to the pathogen.

The study of samples of clinical and biological material from humans was conducted with informed consent of patients, for minors — with the permission of parents (official representatives). The study protocol was approved by the decision of the National Ethical Committee of the Ministry of Health of the Republic of Guinea (protocol No. 129/CNERS/16 of August 31, 2015).

Blood serum of farm animals

Blood samples were obtained at slaughterhouses, using generally accepted methods, from adult animals (more than 1.5 years old) without signs of infectious diseases after their examination by a veterinarian. In total, a panel of 1074 cattle blood samples was formed for the work. The obtained sera were tested by ELISA and PCR methods using “ID Screen Q Fever Indirect Multi-species” reagent kits for detection of IgG antibodies specific to C. burnetii (ID Screen), which is recommended as a veterinary assay, and C. burnetii DNA was detected by the AmpliSens Coxiella burnetii-FL reagent kit (Central Research Institute of Epidemiology, Russia).

Tick suspensions

Ixodes ticks were collected in all 4 landscape-geographical zones of Guinea. Ectoparasites were removed manually, using personal protective equipment, from humans, farm animals, domestic and stray dogs and cats, small mammals, and reptiles. A total of 4709 specimens of ticks were collected during the studies, which were classified into 11 species based on morphological features: Amblyomma variegatum Fabricius, 1794; Haemaphysalis leachi Audouin, 1826; Hyalomma rufipes Koch, 1844; Hyalomma truncatum Koch, 1844; Rhipicephalus (Boophilus) decoloratus Koch, 1844; Rhipicephalus (Boophilus) geigyi Aeschliman & Morel, 1965; Rhipicephalus (Boophilus) annulatus Say, 1821; Rhipicephalus (Boophilus) microplus Canestrini, 1888; Rhipicephalus lunulatus Neumann, 1907; Rhipicephalus sanguineus Latreille, 1806; Rhipicephalus senegalensis Koch, 1844 according to the identification guide [22]. Further, 1648 pools were formed taking into account species, sex, developmental phase and fatness of individual mites, as well as places of ectoparasite collection. Ectoparasites were washed twice with 70% ethanol to remove external contaminants and external microflora. Samples were prepared using a TissueLyser II laboratory homogenizer (Qiagen) in 500 µl of sterile phosphate-salt buffer solution.

The obtained material was tested by PCR and ELISA methods using the AmpliSens Coxiella burnetii-FL reagent kit (Central Research Institute of Epidemiology) and ELISA-Qu-antigen (kit N1) test system for detection of Coxiella burnetii antigens (Pasteur Research Institute of Epidemiology and Microbiology), respectively. Some samples containing both DNA and antigens of C. burnetii were analyzed using high-throughput sequencing on the Ion S5 platform (Thermo Scientific); further reads were mapped to the 16S rRNA sequence from the NCBI GenBank database using the BWA algorithm [23]. The plasmid profile with specific primers to the QpH1, QpRS and QpDV plasmid loci was also studied.

Small mammal organ suspensions

During epizootological monitoring on the territory of Guinea, 319 specimens of small mammals (Rodentia, Eulipotyphla) were captured. The species spectrum of rodents was represented by 13 species: Arvicanthis ansorgei Thomas, 1910 (Sudan grass mouse); Heliosciurus gambianus Ogibly, 1835 (Gambian squirrel); Cricetomys gambianus Waterhouse, 1840 (Gambian hamster rat); Lemniscomys striatus Linnaeus, 1758 (striped mouse); Lophuromys sikapusi Temminck, 1853 (rusty-bellied stiff-necked mouse); Mastomys erythroleucus Temminck, 1853 (Guinean multispotted mouse); Mastomys natalensis A. Smith, 1834 (Natal mouse); Mus minutoides A. Smith, 1834 (dwarf mouse); Mus musculoides Temminck, 1853 (Temminck's mouse); Praomys daltoni Thomas, 1892 (Dalton's mouse); Rattus rattus Linnaeus, 1758 (black rat); Crocidura olivieri Lesson, 1827 (African giant whitetooth); Crocidura sp. Wagler, 1832 (whitetooths) [24–28].

We obtained 298 specimens of bats (Chiroptera) of 14 species: Eidolon helvum Kerr, 1792 (palmate wing); Epomophorus gambianus Ogilby, 1835 (great epaulet wing); Lissonycteris angolensis Bocage, 1898 (Angolan flying dog); Rousettus aegyptiacus E. Geoffroy, 1810 (Egyptian flying dog); Chaerephon pumillus Cretzschmar, 1830 (dwarf folding spoonbill); Mops condylurus A. Smith, 1833 (Angolan folding spoonbill); Hipposideros caffer Sundevall, 1846 (South African leafhopper); Hipposideros jonesi Hayman, 1947 (Jones' leafhopper); Hipposideros ruber Noack, 1893 (red leafhopper); Nycteris hispida Schreber, 1775 (shaggy slitmouth); Neoromicia guineensis Bocage, 1889 (Guinean leatherback); Scotophilus dinganii A. Smith, 1833 (African smooth-nosed platypus); Scotophilus leucogaster Cretzschmar, 1830 (white-bellied house smooth-nosed platypus); Rhinolophus alcyone Temminck, 1853 (Ghanaian horseshoe) [24-27].

Mammals were dissected in compliance with the rules of biological safety no later than 3 h after capture. In the absence of such an opportunity, animal carcasses were frozen at –20ºС and delivered to the laboratory, where they were subsequently dissected and organ samples were taken. Combined suspensions of lungs and kidneys were used as material for work, in which markers of the coxiellosis pathogen (DNA and antigens) were searched with the reagent kits mentioned above.

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 was approved by the Bioethics Commission of the Russian Anti-Plague Institute “Microbe” (protocol No. 8 of November 21, 2023).

During statistical processing of the material we calculated the proportion of detected pathogen markers in each sample, 95% confidence intervals (CI) for the proportions using Wilson's method.

Results and discussion

Identification of human cases of Q fever in Guinea

To date, there has been no detection of suspected cases of Q fever in Guinea. This can be explained by the lack of alertness of health workers in local hospitals to this infectious disease. In this regard, a case of the disease reported for the first time in the country is of great interest.

Patient D., 28 years old, living in Mamou (Middle Guinea), was admitted to the infectious disease department of a regional hospital. At hospitalization, the patient had prolonged (more than 1 month), subfebrile fever, muscle and joint pains and breathing difficulties. The results of immunochemistry and microscopy tests for detection of malaria pathogens were negative.

For further differential diagnosis, the patient's blood serum was sent to the Center's laboratory. The obtained material was analyzed by reverse transcription PCR to detect RNA of Ebola, yellow fever, West Nile, dengue, Zika, Crimean-Congo hemorrhagic fever, hepatitis C, 16S RNA of leptospirosis pathogens, DNA of hepatitis B virus, pathogens of Q fever and rickettsioses. Based on the results, C. burnetii DNA was detected in the patient's serum. The material was also tested using ELISA and specific IgM antibodies to coxiellae were detected in a titer of 1 : 400. Subsequently, the obtained blood sample was used to determine the nucleotide sequence of the DNA of the Q fever pathogen. Partial sequencing with specific primers revealed 99% identity of the tested sample with the genome of C. burnetii. Phylogenetic analysis using the BLAST algorithm¹ showed 96% homology with strains isolated in Namibia.

When interviewed, patient D. mentioned close contact with farm animals, specifically owned cattle, and also indicated that there had been cases of spontaneous abortions of cattle in the patient's village.

Neither genetic markers of C. burnetii nor specific IgM antibodies to coxiellae were detected in the remaining serum samples from febrile patients transported from Guinea hospitals.

Determination of the herd immunity of Guineans to the Q fever pathogen

In the present study, specific IgG antibodies to the Q fever pathogen were detected in sera of participants of all age groups living in different zones of Guinea, and there was no dependence of the antibody detection rates on the sex of the examined persons (Table 1). In the whole country, specific immunoglobulins to C. burnetii were registered in 366 out of 3156 serum samples, which amounted to 11.6% (95% CI 10.5-12.8).

 

Table 1. Identification of specific IgG antibodies to the Q fever pathogen in the blood sera of residents of the Republic of Guinea

Age, years	Number of samples
	total	men			women
		total	positive	% (95% CI)	total	positive	% (95% CI)
< 10	197	108	8	7.4 (3.8–13.9)	89	6	6.7 (3.1–13.9)
10–20	498	275	26	9.4 (6.5–13.4)	223	27	12.1 (8.4–17.0)
20–30	699	340	32	9.4 (6.7–12.9)	359	29	8.1 (5.7–11.4)
30–40	595	300	39	13.0 (9.7–17.3)	295	33	11.2 (8.1–15.3)
40–50	559	285	35	12.3 (8.9–16.6)	277	29	10.5 (7.4–14.6)
50–60	339	230	37	16.1 (11.9–21.4)	109	26	23.8 (16.8–32.6)
> 70	269	102	20	19.6 (13.1–28.3)	167	19	11.4 (7.4–17.1)
Total	3156	1637	197	12.1 (10.5–13.7)	1519	169	11.3 (9.6–12.8)

 

Determination of the herd immunity of farm animals to the Q fever pathogen

One of the indicators of circulation of pathogens of naturally occurring infectious diseases in a certain area is the detection of specific IgG immunoglobulins in blood sera of farm animals living in this region.

As a result of this work, antibodies to the Q fever pathogen were detected in 172 samples, which amounted to 16.0% (95% CI 13.9-18.3). Positive results were recorded in all landscape-geographical zones).

Detection of specific markers (DNA and antigens) of the Q fever pathogen in tick suspensions

PCR and ELISA methods were used to examine suspensions of ixodid ticks of various species, which are the main vectors of C. burnetii, collected in all landscape and geographical zones of Guinea. The pathogen DNA was detected in 294 (17.9%) samples and antigen in 307 (18.7%). Positive findings were noted among all ixodid tick species represented in the work, but the majority were attributed to Am. variegatum, Hy. truncatum, Rh. decoloratus (Table 2).

 

Table 2. Identification of C. burnetii markers in suspensions of ixodid ticks of different species collected in the territory of the Republic of Guinea

Tick species	Number of samples (copies)	The number of positive samples; % (95% СI)
		PCR	ELISA
Am. variegatum	872 (2493)	159; 18.2 (15.8–20.9)	193; 22.1 (19.5–25.0)
Ha. leachi	16 (56)	0	0
Hy. truncatum	52 (95)	14; 26.9 (16.8–40.3)	16; 30.8 (19.9–44.3)
Rh. annulatus	58 (161)	36; 62.1 (49.2–73.4)	29; 50 (37.5–62.5)
Rh. decoloratus	391 (1104)	47; 12 (9.2–15.6)	37; 9.5 (6.9–12.8)
Rh. geigyi	210 (668)	36; 17.1 (12.7–22.8)	29; 13.8 (9.8–19.1)
Rh. microplus	18 (47)	0	1; 5.6 (1.0–25.8)
Rh. sanguineus	10 (42)	0	1; 10 (1.8–40.4)
Rh. senegalensis	18 (29)	2; 11.1 (3.1–32.8)	1; 5.6 (1.0–25.8)
Rh. lunulatus	2 (11)	0	0
Hy. rufipes	1 (3)	0	0
Total	1648 (4709)	294; 17.8 (16.1–19.8)	307; 18.6 (16.8–20.6)

 

Analysis of plasmid profiles is an important tool for studying the spread of Q fever and determining the type of the pathogen. For genetic typing of C. burnetii, a panel of 20 samples from different tick species was created, in which both DNA (Ct level not more than 15) and antigen of the pathogen were detected simultaneously. PCR with specific primers to the QpH1, QpRS and QpDV plasmid loci revealed the presence of QpH1 alone in 5 samples. Sequences of QpRS and QpDV plasmid fragments were not detected in any of the samples. In the course of analyzing the results obtained and literature data, it was found that strains carrying the QpH1 plasmid are widespread in Equatorial Africa and are capable of causing diseases in humans and animals [29, 30], which does not exclude the possibility of their circulation in Guinea.

The generated panel of samples was analyzed using high-throughput sequencing methods on the Ion S5 platform (Thermo Scientific). As a result, the nucleotide sequence of 16S rRNA of the Q fever pathogen was determined in 8 samples, which coincides 99.9% with the reference strain presented in the NCBI GenBank database. When comparing the obtained consensus sequence with the NCBI BLAST database, C. burnetii strains isolated in Namibia were found to show homology (96%) with the studied sample. Furthermore, the obtained reads were classified by the kraken2 algorithm using the Greengenes 16S RNA base, which also showed that the investigated sample belonged to the C. burnetii species. Some of the obtained 16S rRNA nucleotide sequences with the highest quality reads were deposited in the international GenBank database under the numbers OQ152497-OQ152500.

Detection of specific markers (DNA and antigens) of the Q fever pathogen in organ suspensions of small mammals

As a result of PCR and ELISA tests, markers of the Q fever pathogen were detected in the material collected in all zones of Guinea. Antigen was detected in 0.9% of samples and DNA in 5.1%. The maximum number of positive findings was obtained when samples from Mastomys erythroleucus rodents was examined (Table 3). These data may indicate the participation of animals of this systematic group in the spread of C. burnetii in Guinea.

 

Table 3. Identification of C. burnetii markers in suspensions of organs of small mammals of different species collected on the territory of the Republic of Guinea

Small mammal species	Number of samples (copies)	The number of positive samples; % (95% СI)
		PCR	ELISA
Arvicanthis ansorgei	3	0	0
Heliosciurus gambianus	4	0	0
Cricetomys gambianus	7	1; 14.3 (2.6–51.3)	0
Lemniscomys striatus	3	0	0
Lophuromys sikapusi	1	0	0
Mastomys erythroleucus	124	8; 6.5 (3.3–12.2)	2; 1.6 (0.4–5.7)
Mastomys natalensis	32	2; 6.3 (1.7–20.1)	0
Mus minutoides	5	0	0
Mus musculoides	16	1; 6.3 (1.1–28.3)	0
Praomys daltoni	6	0	0
Rattus rattus	96	4; 4.2 (1.6–10.2)	1; 1.0 (0.2–5.7)
Crocidura olivieri	7	0	0
Crocidura sp.	15	0	0
Total	319	16; 5.0 (3.1–8.0)	3; 0.9 (0.3–2.7)

 

Detection of specific markers (DNA and antigens) of the Q fever pathogen in organ suspensions of bats

Examination of pooled samples of lungs and kidneys obtained from bats revealed both C. burnetii antigens (1% of cases) and DNA (2%). The majority of positive samples were formed from organs of Scotophilus leucogaster (Table 4). Representatives of this species are widely distributed throughout sub-Saharan Africa. The data obtained confirm the role of bats in the circulation of the Q fever pathogen, which indicates the need for additional studies to determine the role of these mammals in the ecology of the pathogen.

 

Table 4. Identification of C. burnetii markers in organ suspensions of bats of various species collected on the territory of the Republic of Guinea

Bat species	Number of samples (copies)	The number of positive samples; % (95% СI)
		PCR	ELISA
Eidolon helvum	1	0	0
Epomophorus gambianus	4	0	0
Lissonycteris angolensis	4	0	0
Rousettus aegyptiacus	15	0	0
Chaerephon pumillus	3	0	0
Mops condylurus	26	1; 3.8 (0.7–18.9)	0
Hipposideros caffer	32	0	0
Hipposideros jonesi	25	0	0
Hipposideros ruber	41	1; 2.4 (0.4–12.6)	1; 2.4 (0.4–12.6)
Nycteris hispida	5	0	0
Neoromicia guineensis	23	1; 4.3 (0.8–21.0)	0
Scotophilus dinganii	1	0	0
Scotophilus leucogaster	117	3; 2.6 (0.9–7.3)	2; 1.7 (0.5–6.0)
Rhinolophus alcyone	1	0	0
Total	298	6; 2.0 (0.9–4.3)	3; 1.0 (0.3–2.9)

 

Conclusion

As a result of this work, the distribution of C. burnetii in all landscape-geographical zones of Guinea was studied, including the first case of human case of Q fever identified and laboratory confirmed (Table 5). The role of farm animals, small mammals and bats in the circulation of C. burnetii has been established. It was shown that the main vectors of the pathogen on the territory of Guinea are ixodes ticks of Am. variegatum, Hy. truncatum and Rh. decoloratus species. Molecular genetic studies of the material collected in Guinea revealed C. burnetii strains carrying the QpH1 plasmid, which are capable of causing disease in humans and animals, and for the first time for this region the complete nucleotide sequence of the 16S rRNA gene of the Q fever pathogen was determined and registered in the international GenBank database.

 

Table 5. Identification of markers of the Q fever pathogen in various materials collected on the territory of the Republic of Guinea

Type of the studied samples	Number of samples	The number of positive; % (95% CI)
		PCR	ELISA
		DNA	antigen	IgG
Lower (Maritime) Guinea
Blood serum of practically healthy people	943	N. i.	N. i.	106; 11.2 (9.4–13.4)
Blood serum of cattle	371	6; 1.6 (0.7–3.5)	N. i.	64; 17.2 (13.7–21.4)
Suspensions of ticks	624	111; 17.8 (15.0–21.0)	131; 21.0 (18.0–24.4)	N. i.
Suspensions of organs of small mammals	149	8; 5.4 (2.7–10.2)	0; 0 (0–2.5)	N. i.
Suspensions of bat organs	107	0; 0 (0–3.4)	3; 2.8 (0.9–7.9)	N. i.
Middle Guinea
Blood serum of practically healthy people	778	N. i.	N. i.	82; 10.5 (8.6–12.8)
Blood serum of cattle	257	3; 1.2 (0.4–3.4)	N. i.	49; 19.2 (14.7–24.3)
Suspensions of ticks	402	71; 17.7 (14.2–21.7)	77; 19.1 (15.6–23.3)	N. i.
Suspensions of organs of small mammals	55	3; 5.4 (1.9–14.8)	0; 0 (0–6.5)	N. i.
Suspensions of bat organs	61	0; 0 (0–5.8)	0; 0 (0–5.8)	N. i.
Upper Guinea
Blood serum of practically healthy people	655	N. i.	N. i.	77; 11.8 (9.5–14.4)
Blood serum of cattle	182	2; 1.1 (0.3–3.9)	N. i.	35; 13.2 (9.6–17.8)
Suspensions of ticks	245	53; 21.6 (16.9–27.2)	28; 0.8 (0.3–2.9)	N. i.
Suspensions of organs of small mammals	43	2; 4.6 (1.3–15.4)	1; 2.3 (0.4–12.1)	N. i.
Suspensions of bat organs	54	0; 0 (0–6.6)	0; 0 (0–6.6)	N. i.
Forest Guinea
Blood serum of practically healthy people	780	N. i.	N. i.	101; 12.9 (10.7–15.5)
Blood serum of cattle	264	3; 1.1 (0.4–3.3)	N. i.	35; 13.2 (9.6–17.8)
Suspensions of ticks	377	59; 15.6 (12.3–19.7)	61; 16.2 (12.8–20.2)	N. i.
Suspensions of organs of small mammals	72	3; 4.2 (1.4–11.5)	2; 2.8 (0.8–9.5)	N. i.
Suspensions of bat organs	76	6; 7.9 (3.7–16.1)	0; 0 (0–4.8)	N. i.
General by country
Blood serum of practically healthy people	3156	N. i.	N. i.	366; 11.6 (10.5–12.7)
Blood serum of cattle	1074	14; 1.3 (0.8–2.1)	N. i.	172; 16.0 (13.9–18.3)
Suspensions of ticks	1648	294; 17.8 (16.1–19.8)	307; 18.6 (16.8–20.6)	N. i.
Suspensions of organs of small mammals	319	16; 5.0 (3.1–8.0)	3; 0.9 (0.3–2.7)	N. i.
Suspensions of bat organs	298	6; 2.0 (0.9–4.3)	3; 1.0 (0.3–2.9)	N. i.

Note. N. i. — not investigated.

 

Our study allowed us to expand the data on the circulation and distribution of C. burnetii in West Africa. The study of the specifics of C. burnetii circulation in Guinea remains an urgent task. Systematically obtained data on the detection of the pathogen and assessment of risk factors for outbreaks of diseases caused by coxiellae are necessary for the development of an algorithm for laboratory diagnosis and recommendations for clinicians. Regular monitoring of the spread of Q fever, carried out with the participation of both medical and veterinary services in Guinea, will make it possible to forecast the epidemiological situation and coordinate preventive (anti-epidemic) measures within the framework of the One Health concept².

 

¹ URL: https://blast.ncbi.nlm.nih.gov/Blast.cgi

² WHO. One health. URL: https://www.who.int/health-topics/one-health#tab=tab_1 (дата обращения: 26.05.2024).

About the authors

Ekaterina V. Naidenova

Russian Research Anti-Plague Institute «Microbe»

Author for correspondence.
Email: katim2003@mail.ru
ORCID iD: 0000-0001-6474-3696

senior researcher, Department of infectious disease diagnostics

Россия, Saratov

Kirill S. Zakharov

Russian Research Anti-Plague Institute «Microbe»

Email: katim2003@mail.ru
ORCID iD: 0000-0002-4726-309X

senior researcher, Department of infectious disease epidemiology

Россия, Saratov

Dmitry A. Agafonov

Russian Research Anti-Plague Institute «Microbe»

Email: katim2003@mail.ru
ORCID iD: 0000-0001-9273-6063

старший научный сотрудник отдела диагностики инфекционных болезней ФКУН Российский противочумный институт «Микроб» Роспотребнадзора, к.б.н.

Россия, Saratov

Mikhail Yu. Kartashov

State Scientific Center of Virology and Biotechnology «Vector»

Email: katim2003@mail.ru
ORCID iD: 0000-0002-7857-6822

Cand. Sci. (Biol.), senior researcher, Department of molecular virology of flaviviruses and viral hepatitis

Россия, Kol’tsovo

Aislu M. Senichkina

Russian Research Anti-Plague Institute «Microbe»

Email: katim2003@mail.ru
ORCID iD: 0000-0003-1026-2680

Cand. Sci. (Biol.), senior researcher, Department of diagnostics of infectious diseases

Россия, Saratov

Erik S. Khalilov

Saint Petersburg Pasteur Research Institute of Epidemiology and Microbiology

Email: katim2003@mail.ru
ORCID iD: 0000-0002-0599-4302

junior researcher, Laboratory of zoonotic infections

Россия, St. Petersburg

Abdoul B. Ibrahim

Research Institute of Applied Biology of Guinea

Email: katim2003@mail.ru
ORCID iD: 0009-0003-2547-8705

researcher, Laboratory of viral hemorrhagic fevers of Guinea

Гвинея, Kindia

Mamadou B. Bah

Research Institute of Applied Biology of Guinea

Email: katim2003@mail.ru
ORCID iD: 0000-0002-4565-269X

researcher

Гвинея, Kindia

Ibrahim Nourdine

Research Institute of Applied Biology of Guinea; Virology Research Center

Email: katim2003@mail.ru
ORCID iD: 0000-0002-2970-9676

Cand. Sci. (Biol.), researcher, Laboratory of viral hemorrhagic fevers of Guinea

Гвинея, Kindia; Conakry

Nikolai K. Tokarevich

Saint Petersburg Pasteur Research Institute of Epidemiology and Microbiology

Email: katim2003@mail.ru
ORCID iD: 0000-0001-6433-3486

D. Sci. (Med.), Professor, Head, Laboratory of zooanthroponotic infections

Россия, St. Petersburg

Sanaba Boumbaly

Research Institute of Applied Biology of Guinea; Virology Research Center

Email: katim2003@mail.ru
ORCID iD: 0000-0002-4506-6033

Cand. Sci. (Biol.), Professor, Director, Laboratory of viral hemorrhagic fevers of Guinea

Гвинея, Kindia; Conakry

Yusuf Sidime

Institute of Veterinary Medicine

Email: katim2003@mail.ru
ORCID iD: 0000-0002-0742-0468

Cand. Sci. (Vet.), Professor, Director, Institute of Veterinary Medicine

Гвинея, Dalaba

Svetlana A. Shcherbakova

Russian Research Anti-Plague Institute «Microbe»

Email: katim2003@mail.ru
ORCID iD: 0000-0003-1143-4069

D. Sci. (Biol.), Deputy director

Россия, Saratov

Vladimir V. Kutyrev

Russian Research Anti-Plague Institute «Microbe»

Email: katim2003@mail.ru
ORCID iD: 0000-0003-3788-3452

D. Sci. (Med.), Professor, Academician of the RAS, Director, Russian Anti-Plague Institute "Microbe"

Россия, Saratov

References

Supplementary files