Epidemiological Cycle Research Articles

Drugs for Vector-Borne Protozoal Diseases in a One Health Scenario. A European Perspective.

Vector-borne protozoal diseases (VBPD) represent an enormous health and economic burden, particularly in low- and middle-income countries. Their control requires integrated approaches that consider not only therapeutic interventions for affected human and animal populations but also preventive tools. Environmental contamination can lead to therapeutic ineffectiveness. Effective intervention must consider in-depth knowledge of the environmental factors that regulate the exposure, transmission and pathogenicity of VBPD within a One Health approach. In recent decades, the incidence and prevalence of VBPD have been substantially reduced in many regions of the world, although there are still hot spots and emerging epidemiological cycles. Except for a partially protective vaccine against malaria, vaccination is not available for any other human VBPD, and therefore epidemiological control and chemotherapy are the main control tools. Current therapeutics have several drawbacks, including reduced efficacy, toxicity and high price of safer formulations. In addition, the industrial pipeline is limited, and no therapeutic breakthroughs are expected. Integrated control of VBPD requires multitarget control systems adapted to the disease and region. In this scenario, harmonized surveillance systems, accurate reporting and increased public and private investment will ensure more rational use of the few available and new drugs.

Seroepidemiology of Coxiella burnetii in Domestic and Wild Ruminant Species in Southern Spain.

The European Food Safety Authority has recently listed Q fever as a priority for setting up a coordinated surveillance system. Although Spain is the country with the highest human incidence of the disease in the European Union, updated data on Coxiella burnetii in ruminants are still limited. A total of 780 serum samples from small ruminants and 605 sera from wild ruminants were collected in the Mediterranean ecosystems of southern Spain during the period 2015-2023. Anti-C. burnetii antibodies were detected using a commercial indirect ELISA. The overall individual seroprevalence in the small ruminants was 49.1% (383/780; 95% CI: 45.6-52.6). Antibodies against C. burnetii were identified in 40.0% (156/390) of sheep and in 58.2% (227/390) of goats. At least one seropositive animal was observed in all sheep (100%) and in 92.3% of goat flocks. The species (goat) and the existence of reproductive disorders in primiparous females were potential risk factors for C. burnetii exposure in small ruminant farms. In the wild ruminants, the overall seroprevalence against C. burnetii was 1.5% (9/605; 95% CI: 0.8-2.8). Anti-C. burnetii antibodies were found in 1.8% (2/110) of mouflon, 1.5% (6/390) of red deer, and 1.0% (1/105) of Iberian ibex. The high exposure of the small ruminants to C. burnetii, particularly in goats, detected in the present study is of animal and public health concern. Our results denote that wild ruminants only play a minor role in the epidemiology of this bacterium in southern Spain and suggest an independent epidemiological cycle of C. burnetii in domestic and wild ruminant species in the study area.

Bartonella spp. in Phlebotominae Sand Flies, Brazil.

Bartonella spp. are opportunistic, vectorborne bacteria that can cause disease in both animals and humans. We investigated the molecular occurrence of Bartonella spp. in 634 phlebotomine sand fly specimens, belonging to 44 different sand fly species, sampled during 2017-2021 in north and northeastern Brazil. We detected Bartonella sp. DNA in 8.7% (55/634) of the specimens by using a quantitative real-time PCR targeting the 16S-23S internal transcribed spacer intergenic region. Phylogenetic analysis positioned the Lutzomyia longipalpis sand fly-associated Bartonella gltA gene sequence in the same subclade as Bartonella ancashensis sequences and revealed a Bartonella sp. sequence in a Dampfomyia beltrani sand fly from Mexico. We amplified a bat-associated Bartonella nuoG sequence from a specimen of Nyssomyia antunesi sand fly. Our findings document the presence of Bartonella DNA in sand flies from Brazil, suggesting possible involvement of these insects in the epidemiologic cycle of Bartonella species.

Clinical Presentations of Parvovirus B19: A Case Series.

Parvovirus B19 (PVB19) is a small, nonenveloped, single-stranded DNA virus commonly causing asymptomatic infections or mild, flu-like symptoms. In children, PVB19 can lead to various clinical conditions, including erythema infectiosum, arthropathy, transient aplastic crisis and papular-purpuric eruptions, among others. We present 3 pediatric cases treated at Luigi Sacco University Hospital in Milan, Italy, in March 2024, each demonstrating distinct manifestations of PVB19 infection. Case 1 involved a 7-year-old girl with a maculopapular rash and panniculitis-like symptoms. Case 2 described an 8-year-old boy with a maculopapular rash, vasculitis component and mild thrombocytopenia. Case 3 focused on a 7-year-old girl with petechial and purpuric eruptions and a mild decrease in platelets. Serological tests confirmed PVB19 infection in all cases. The discussed cases highlight the heterogeneous clinical spectrum of PVB19 infection and emphasize its potential to cause thrombocytopenia even in healthy children. The recent surge in PVB19 cases in Europe, aligned with known epidemiological cycles, underscores the importance of vigilance in diagnosis, particularly during peak seasons. Additionally, concerning the role of serological testing in the diagnostic process, the potential for cross-reactivity among viral antigens is pointed out. PVB19 is a common infection with a broad range of clinical presentations. Awareness of its potential complications, including thrombocytopenia, even in nonimmunocompromised children, is crucial. Moreover, understanding the epidemiological patterns of PVB19 can aid in anticipating and managing outbreaks, thus minimizing its impact on pediatric health.

Assessing leptospirosis and toxoplasmosis seropositivity in wild boars (Sus scrofa): Implications for public and animal health in Southern Brazil

Leptospirosis and toxoplasmosis are re-emerging zoonosis caused by infection with pathogenic spirochaetes of Leptospira and the protozoa Toxoplasma gondii, respectively. Wild boars (Sus scrofa), an exotic invasive species in Brazil, could play a role in the diseases’ epidemiological cycles, but this issue is still unexplored. This study aimed to evaluate the Leptospira spp. and T. gondii seropositivity in wild boars in Rio Grande do Sul state, south Brazil. Of evaluated animals, 16% (13/80) and 85% (52/61) had antibodies to T. gondii and Leptospira spp., respectively. Sex, weight, age, hunt location and season of hunt were evaluated by their association with seropositivity for both pathogens, but none of them had statistical significance. This study revealed that wild boars should be considered as a potential source of Leptospira spp. and T. gondii dissemination for humans and animal species in shared environments in Rio Grande do Sul state.

Genetically divergent 'Candidatus Phytoplasma solani' isolates in Croatian vineyard pathosystems suggest complex epidemiological networks

'Candidatus Phytoplasma solani’ (CPs), a phytoplasma endemic to the Euro-Mediterranean basin is a causative agent of several plant diseases, including the grapevine yellows disease “bois noir” (BN). As different CPs strains have been shown to have different ecological reservoirs and pathways for spread, the genetic characterization of CPs strains is a prerequisite, and better control of BN relies on the identification of reservoir plants. The variability of the phytoplasma genotypes involved in the BN pathosystem in Croatian vineyards was assessed by a multilocus sequence typing (MLST) approach. The genotyping was performed on selected grapevine, wild plants, and insects collected within the eleven years of national survey conducted in all Croatian viticultural regions. The extensive tuf, secY, stamp, and vmp1 genes-based MLST analyses revealed two new genotypes for stamp and vmp1 genes, designated as ST59 and V28, respectively, and overall identified 28 different CPs MLST genotypes. The prevalent MLST genotype in grapevine CPsSqt21 (S6/ST6/V18/tuf-b2) was widespread in nine counties across Uplands, Slavonia, and Danube wine regions and was affiliated to the known vector Hyalesthes obsoletus and to Urtica dioica. The other two most frequent genotypes were the U. dioica-associated CPsSqt28 (S39/ST46/V3/tuf-a) and the C. arvensis-associated CPsSqt2 (S1/ST9/V4/tuf-b1). CPs of different vmp1 genotypes was also detected in Cixius wagneri specimens originating from different parts of Croatia. In addition, CPs was detected in several Dichtyophara europaea insects and in two new potential plant reservoirs Ailanthus altissima and Robinia pseudoacacia. The substantial number of found MLST genotypes indicates the presence of several independent epidemiological cycles and is certainly a consequence of a unique geographical position of Croatia, bridging the different eco-climatic areas of central and south-eastern Europe.

Serological and molecular survey of Q fever in the dog population of the Campania region, southern Italy

Q fever is a re-emerging zoonosis whose epidemiological cycle in ruminants is well defined, while the role of other species (including pets) is still debated. In this study, the serological and molecular prevalence of Coxiella burnetii in a sample of dogs in the Campania region, southern Italy was evaluated. A seroprevalence of 5.97 % (16/268) was observed using a commercial multispecies ELISA, compared to only 2.7 % (5/197) at the molecular level. No risk factors correlated with higher levels of exposure except for the size of the animal (small dogs showed significantly higher seroprevalence). Positive samples were further evaluated for reactivity to phase I and II antigens using IFA and phase-specific ELISAs (for specific IgG detection). Two animals showed antibodies against both phases of infection, suggesting that Coxiella burnetii seroconversion in dogs follows similar dynamics to those observed in ruminants.One of the five samples that showed positive results in real-time PCR was confirmed at the PCR endpoint and showed similarity with other Coxiella spp. strains detected in tick and dog samples when sequenced.In this study, we demonstrated exposure to Coxiella burnetii for different categories of dogs in southern Italy, including pet dogs living indoors. Since reports of transmission of infection from pets to humans have been described in both rural and urban areas, careful surveillance of these species is also necessary. In the lack of additional information, comprehending the risk to humans requires monitoring of wild and domestic animal populations.

First Seroepidemiological Study of Toxoplasma gondii Infection in Dromedaries (Camelus dromedarius) in Southern Tunisia

Toxoplasma gondii is one of the most common zoonotic parasites worldwide, with infections in humans as well as in all mammals, including dromedaries, that affect reproductive health, leading to malformations and abortions. In the current study, we estimated, for the first time in Tunisia, the seroprevalence of T. gondii antibodies and its associated risk factors in dromedaries (Camelus dromedarius) using the enzyme-linked immunosorbent assay (ELISA) technique. A total of 248 sera samples were collected from dromedaries living in Médenine and Tataouine governorates, South Tunisia. The overall seroprevalence of T. gondii was estimated to be 29.8 ± 2.9% (74/248) with a significantly higher seroprevalence rate in dromedaries from Médenine (52.5 ± 7.9%; 21/40) compared to Tataouine (25.5 ± 3%; 53/208); it was also higher in dromedaries kept in intensive farming systems (55 ± 11.1%; 11/20) compared to extensive systems (27.6 ± 3%; 63/228), in non-pregnant females (39 ± 4%; 57/146) compared to pregnant ones (16.7 ± 3.7%; 17/102), and in those in contact with cats (66.7 ± 8.6%; 20/30) compared to those with no contact with cats (24.8 ± 2.9%; 54/218). The present study should be followed by others to explore the role of dromedaries in the epidemiological cycle of T. gondii in Southern Tunisia.

Bluetongue virus in Culicoides spp. in Manabí province, Ecuador

Bluetongue is a viral disease that affects sheep, cattle and other domestic or wild ruminants. Different species of Culicoides transmit the virus (BTV). High BTV seroprevalence was found in farms of Manabí and other two provinces of Ecuador, but the presence of the virus in the Culicoides spp. vector has not been reported. In the current study, the main goal was to demonstrate the presence of BTV in Culicoides in Ecuador for the first time and characterize the species of Culicoides collected in farms located in the central-east area of Manabí province. Six farms were selected to be monitored by BTV c-ELISA. All the 100 tested animals were positive. Using a CDC trap with ultraviolet light placed in three BTV-positive farms for three nights, 2240 specimens of Culicoides were collected. Six different Culicoides species have been identi-fied, which were presented in different abundance percent: 62% C.insignis; 7% C. batesi; 1.8% C.foxi; 1.8% C.diabolicus; 15.48% C.crepuscularis; 12% C.antunesis. These last two species have been identified for the first time in Ecuador. Q-PCR detected BTV RNA in the homogenates of female midges collected in each farm, so it was demonstrated that the epidemiological cycle of the virus is completed; since female midges infected with BTV were found, it is too a novel result for Ecuador. Keywords: Bluetongue, BTV, Culicoides, cattle, real-time PCR, competitive ELISA, Ecuador, Manabi

Occurrence of Coxiella burnetii in wild lagomorphs and their ticks in Spanish Mediterranean ecosystems.

Coxiella burnetii, the causative agent of Q fever, is a zoonotic multi-host vector-borne pathogen of major public health importance. Although the European Food Safety Authority has recently made the monitoring of this bacterium in wildlife a priority, the role of wild lagomorphs in the transmission and maintenance of C. burnetii is poorly understood. The aims of this study were to determine the prevalence and risk factors associated with C. burnetii circulation in European wild rabbits (Oryctolagus cuniculus) and Iberian hares (Lepus granatensis) and to assess the presence of this pathogen in ticks that feed on them in Mediterranean ecosystems in Spain, the country with the highest number of reported cases of Q fever in Europe. A total of 574 spleen samples were collected from 453 wild rabbits and 121 Iberian hares, and 513 ticks (processed in 120 pools) between the 2017/2018 and 2021/2022 hunting seasons. C. burnetii DNA was detected in 103 (17.9%; 95% CI: 14.8-21.1) of the 574 wild lagomorphs tested. By species, prevalence was 16.3% (74/453; 95% CI: 12.9-19.7) in the European wild rabbit and 24.0% (29/121; 95% CI: 16.4-31.6) in the Iberian hare. At least one positive lagomorph was found on 47.9% of the 96 hunting estates sampled and in every hunting season since 2018/2019. Two risk factors associated with C. burnetii infection were as follows: outbreak of myxomatosis on the hunting estate in the month prior to sampling and high tick abundance observed by gamekeepers on the hunting estate. C. burnetii DNA was also found in 33 of the 120 (27.5%; 95% CI: 19.5-35.5) tick pools tested. The pathogen was detected in 66.7% (4/6), 29.2% (26/89) and 21.4% (3/14) of Haemaphysalis hispanica, Rhipicephalus pusillus and Hyalomma lusitanicum pools respectively. This study provides new epidemiological data on C. burnetii in European wild rabbits and is the first survey on this zoonotic pathogen performed in Iberian hares. Our results indicate widespread endemic circulation of C. burnetii and highlight the importance of both wild lagomorph species as natural reservoirs of this zoonotic bacterium in Mediterranean ecosystems in southern Spain, which may be of public and animal health concern. The high prevalence and wide diversity of positive tick species suggest the possible role of ticks in the epidemiological cycle of C. burnetii, with the potential risk of transmission to sympatric species, including humans.

Anaplasma phagocytophilum in urban and peri-urban passerine birds in Ile-de-France

Wild animals in general, birds in particular, play a key role in transporting ticks and propagating tick-borne pathogens. Several studies have confirmed the infection of birds with Anaplasma phagocytophilum, with overall prevalence varying widely from country to country and/or study to study. This zoonotic bacterium, transmitted mainly by ticks of the genus Ixodes, is responsible for granulocytic anaplasmosis in humans (HGA) and domestic animals (cats, dogs, horses). The disease is also called tick-borne fever (TBF) in ruminants. Extremely rare in the USA, TBF is very common in Europe, where it causes economic losses in livestock. Conversely, HGA is well established in the USA whereas only a few less severe cases have been observed in Europe. Current typing techniques support the existence of multiple variants with differences in virulence/pathogenicity and tropism for certain tick and host species. However, epidemiological cycles remain difficult to characterize in Europe. Several studies describe a cycle apparently involving only birds in Europe, but no such study has been conducted in mainland France. Our objectives were to search for A. phagocytophilum in passerine birds in the Ile-de-France region and to explore their diversity using groEL and ankA gene typing and multilocus sequence typing (MLST). Various tissues (spleen, liver, and skin) were collected from cadavers of 680 passerines between March and December 2021. The presence of A. phagocytophilum was detected by qPCR Taqman targeting the msp2 gene. Three blackbirds (Turdus merula) were found positive, representing detection rates of 0.4 % in all birds tested and 3.3 % in blackbirds. The higher frequency of detection in blackbirds could be at least partially explained by their lifestyle, as they feed on the ground. Analysis of the results of groEL and ankA typing and MLST from positive blackbirds support the hypothesis that the avian A. phagocytophilum strains in Ile-de-France are distinct from those found in mammals, and that they form their own cluster in Europe.

Surveillance of Sarcoptic Mange in Iberian Ibexes (Capra pyrenaica) and Domestic Goats (Capra hircus) in Southern Spain.

Sarcoptic mange is a highly contagious skin disease caused by Sarcoptes scabiei. Sera were collected from 411 Iberian ibexes, comprising 157 individuals with sarcoptic mange skin lesions and 254 clinically healthy animals, in 13 population nuclei across Andalusia (southern Spain) between 2015 and 2021. Skin samples from 88 of the 157 animals with mange-compatible lesions were also obtained. Moreover, 392 serum samples from domestic goats (Capra hircus) were collected in the same region and study period. Antibodies against S. scabiei were tested using an in-house indirect ELISA, while the presence of mites of S. scabiei was evaluated in the skin samples by potassium hydroxide digestion. Seropositivity was found in eight (3.1%) of the clinically healthy ibexes and in 104 (66.2%) of the animals with mange-compatible lesions. The presence of S. scabiei was confirmed in 57 (64.8%) out of the 88 skin samples analysed and anti-S. scabiei antibodies were found in 49 (86.0%) of these 57 mite-positive individuals. Seropositive animals were detected in population nuclei with previous records of sarcoptic mange, where S. scabiei mites were detected by potassium hydroxide digestion in individuals with sarcoptic mange-compatible external lesions. However, seropositivity was not observed in population nuclei that were historically free of this disease. None of the 392 domestic goats had antibodies against S. scabiei, suggesting an independent epidemiological cycle of sarcoptic mange in Iberian ibex populations in the study area, and a limited or null role of domestic goats in the transmission of the parasite to this wild species. Overall, our findings underscore the importance of maintaining and/or implementing integrated surveillance programs and control strategies in wildlife and livestock, to limit the risk of S. scabiei circulation in Iberian ibex populations.

Leptospira spp. detection in bats from the Peninsula of Yucatán, México

The records of Leptospira spp. in bats from México are scarce. It is known that several species of bats are hosts of pathogenic Leptospira spp.; therefore, they participate in the epidemiological cycle and can generate transmission scenarios to people and animals. The aim was to detect the DNA of Leptospira spp. in bats captured in four sites from the Yucatán Peninsula, México. A kidney fragment was collected from the bats and used to extract genomic DNA. Using a PCR, the DNA of Leptospira spp. was detected. Fifty–four bats of the species Desmodus rotundus, Mimon cozumelae, Pteronotus mesoamericanus, Pteronotus fulvus, Nyctinomops laticaudatus, Peropteryx macrotis, Molossus nigricans, Molossus aztecus, Noctilio leporinus, Saccopteryx bilineata and Mormoops megalophylla were studied. The PCR yielded a total frequency of Leptospira spp. of 44.4% (24/54, 95% CI 36.2–71.7%). Species with at least one positive individual were D. rotundus, M. cozumelae, P. mesoamericanus, N. laticaudatus, P. macrotis, M. nigricans, N. leporinus, M. aztecus, and S. bilineata. A high frequency of Leptospira spp. was found in different species of bats belonging to several trophic guilds. The presence of Leptospira spp. in bats is relevant for Public and Animal Health because the evidence indicates that they can generate zoonotic transmission cycles.

Genetic diversity and molecular variability of ’Candidatus Phytoplasma solani’ based on multilocus sequence typing analysis in tomato plantations of western Turkey

‘Candidatus Phytoplasma solani’ (CaPsol) is a very common pathogen in the Euro-Mediterranean regions and has been reported in many countries. Field surveys were conducted in tomato plantations in 2022 to determine the CaPsol infections in the western part of Turkey, which has the highest vegetable production volume. A total of 67 tomato samples, 52 symptomatic and 15 asymptomatic, were collected from four different provinces. A total of thirteen CaPsol strains were identified using molecular techniques from tomato samples. The tuf/stamp/vmp1 genes molecular markers were used to perform molecular and genetic diversity characterizations of these strains. The tuf-b1 genotype and five different stamp genotypes genetically closely related to Eastern European strains were determined in all strains. In addition, these strains showed more than 99% nucleotide sequence similarity with 4 different vmp1 genotypes: V2-TA, V14, V4, and V15. Advanced bioinformatics analyses were performed with stamp (N = 290) and vmp1 (N = 207) strains obtained from this study and GenBank. These analyses showed that the strains for both gene regions descended from two molecular evolutionary ancestors. In order to calculate the genetic distance relationships according to the stamp and vmp1 gene regions, a hierarchical classification was done as geographical and host populations. While these analyses demonstrate the close genetic relationship between Turkish and Eastern European populations, they strongly confirm the importance of the epidemiological cycle between weed, perennial, and insect vectors. Then, molecular variance analyses (AMOVA) were performed on these classified populations. The results indicated high variation for both gene regions but showed that each strain contributed greatly to the CaPsol genetic diversity. Thus, for the first time, multilocus sequence patterns of CaPsol strains obtained from western Turkey were extracted. Extensive genetic analyses have strongly demonstrated the importance of horizontal transmission in the control and epidemiological cycle of CaPsol.

Host–pathogen associations revealed by genotyping of European strains of Anaplasma phagocytophilum to describe natural endemic cycles

BackgroundThe zoonotic intracellular alpha-proteobacterium Anaplasma phagocytophilum is a tick-transmitted pathogen. The associations between vertebrate reservoirs and vectors are described as wide-ranging, and it was previously shown that the pathogenicity of A. phagocytophilum differs depending on the combination of pathogen variant and infected host species. This leads to the question of whether there are variations in particular gene loci associated with different virulence. Therefore, this study aims at clarifying existing host-variant combinations and detecting possible reservoir hosts. To understand these interactions, a complex toolset for molecular epidemiology, phylogeny and network theory was applied.MethodsSequences of up to four gene loci (msp4, msp2, groEL and 16S rRNA) were evaluated for different isolates from variable host species, including, for example, dogs, cattle and deer. Variant typing was conducted for each gene locus individually, and combinations of different gene loci were analysed to gain more detailed information about the genetic plasticity of A. phagocytophilum. Results were displayed as minimum spanning nets and correlation nets.ResultsThe highest diversity of variants for all gene loci was observed in roe deer. In cattle, a reduced number of variants for 16S rRNA [only 16S-20(W) and 16S-22(Y)] but multiple variants of msp4 and groEL were found. For dogs, two msp4 variants [m4-20 and m4-2(B/C)] were found to be linked to different variants of the other three gene loci, creating two main combinations of gene loci variants. Cattle are placed centrally in the minimum spanning net analyses, indicating a crucial role in the transmission cycles by possibly bridging the vector-wildlife cycle to infections of humans and domestic animals. The minimum spanning nets confirmed previously described epidemiological cycles of the bacterium in Europe, showing separation of variants originating from wildlife animals only and a set of variants shared by wild and domestic animals.ConclusionsIn this comprehensive study of 1280 sequences, we found a high number of gene variants only occurring in specific hosts. Additionally, different hosts show unique but also shared variant combinations. The use of our four gene loci expand the knowledge of host–pathogen interactions and may be a starting point to predict future spread and infection risks of A. phagocytophilum in Europe.Graphical abstract

Leptospirosis: toward a better understanding of the environmental lifestyle of Leptospira

Leptospira is a complex bacterial genus which biodiversity has long been overlooked. In the recent years however, environmental studies have contributed to shed light on its original and current environmental habitat. Although very fragile bacteria in laboratories, Leptospira have been shown to successfully occupy a range of soil and freshwater habitats. Recent work has strongly suggested that biofilm formation, a multicellular lifestyle regulated by the second messenger c-di-GMP, might be one strategy developed to overcome the multiple challenges of environmental survival. Within the genus, a minority of pathogenic species have developed the ability to infect mammals and be responsible for leptospirosis. However, most of them have retained their environmental survival capacity, which is required to fulfill their epidemiological cycle. Indeed, susceptible hosts, such as human, suffer from various symptoms, while reservoir hosts stay asymptomatic and release bacteria in the environment. In this review, we discuss how c-di-GMP might be a central regulator allowing pathogenic Leptospira to fulfill this complex life cycle. We conclude by identifying knowledge gaps and propose some hypotheses that should be researched to gain a holistic vision of Leptospira biology.

An unusual identification of Rickettsia parkeri in synanthropic rodents and domiciliated dogs of a rural community from Yucatán, Mexico.

Rickettsia parkeri belongs to the spotted fever group (SFG) of the Rickettsia genus. This bacterium causes mild rickettsiosis in humans and is mainly transmitted by Amblyomma ticks. Its medical importance is emerging in the Americas, including Mexico. Synanthropic rodents and domiciled dogs participate as accidental hosts in epidemiological cycles of Rickettsia of the SFG. The aim is to report the presence of R. parkeri in synanthropic rodents and domiciled dogs from a rural community of Yucatán, Mexico. Rodents were captured, and plasma samples were taken from dogs in 48 households from Ucú, Yucatán, Mexico. A spleen sample (rodents) and plasma (dogs) were used in the propagation of Rickettsiaon Vero cells. These infected cells were used in the extraction of genomic DNA. Rickettsia DNA was identified using a semi-nested PCR (snPCR); some products were sent for sequencing. The recovered sequences were analysed with bioinformatics programs, and a phylogenetic tree was built to determine the Rickettsia species. One hundred animals were sampled: 36 synanthropic rodents and 64 dogs. The snPCR evidenced the presence of Rickettsia DNA in 10 rodents (10/36, 27.8%) and 18 dogs (18/64, 28.1%), which represents a global frequency of 28% (28/100) in this study. The bioinformatics analysis yielded homology to R. parkeri and was demonstrated in the phylogenetic tree. The first evidence of the presence of R. parkeri in synanthropic rodents (Mus musculus) from Mexico is presented; likewise, the participation of domestic dogs in the transmission cycle of this bacterium with potential importance in public health is confirmed.

Sero-prevalence and factors associated with anti-Brucella antibodies in slaughter livestock in Uganda.

Brucellosis is endemic in Uganda and is a major cause of production losses in livestock. Early detection and quantification of the disease is vital for its control and eradication. The aim of this study was to assess the sero-prevalence and factors associated with anti-Brucella antibodies in slaughtered livestock. Sera from 886 cattle, 925 small ruminants, and 900 pigs were collected from regional abattoirs in Northern, Eastern and Central Uganda. To estimate sero-prevalence, sera were serially tested using a combination of the Rose Bengal Test (RBT) and Native Hapten (NH) immunoprecipitation test. True sero-prevalence was estimated using the Rogan-Gladden estimator considering the sensitivity and specificity of the NH immunoprecipitation test. Multivariable logistic regression was used to assess factors associated with seropositivity for anti-Brucella antibodies. Small ruminants showed the highest seroprevalence (6.7%, 95% CI = 4.2-7.1) followed by cattle (3.8%, 95% CI = 2.4-4.9) and pigs (2.8%, 95% CI = 1.1-2.9). Seropositivity for anti-Brucella antibodies was associated with region of origin (OR = 4.6,95%CI=1.49-17.75, p = 0.013) for cattle; sex (OR = 2.90, 95% C = 1.5-6.34, p = 0.004), age (OR=4.04, 95% CI = 1.07-8.52, p = 0.006) and species (OR = 2.53, 95% CI = 1.08-6.98, p = 0.048) for small ruminants; and finally sex for pigs (OR = 2.88, 95% CI = 1.07-8.52, p = 0.041). Progressive control interventions must include both cattle and small ruminants since they play a bigger role in the maintenance and dissemination of Brucella. The interventions should adopt a risk-based approach with regions at higher risk being given top priority. Bacteriological and molecular studies should be undertaken to clarify the role of pigs and the goat-cattle cross infections in the epidemiological cycle of brucellosis in Uganda.

The first identification of Tula orthohantavirus in forest dormice (Rodentia: Gliridae) from Iran

Abstract Orthohantaviruses are a group of zoonotic pathogens that can cause severe and potentially fatal syndromes in humans. Although orthohantaviruses have been documented in Iran, little is known about their potential reservoirs in the country. The present study constitutes the first attempt to detect orthohantavirus infections in rodents in Iran. Sampling was performed in the East Azerbaijan province, during October 2017 and June 2018. To detect orthohantavirus infection, we performed a Pan-hantavirus nested reverse transcription-polymerase chain reaction targeting the large segment of the viral genome using consensus primers on lung tissue samples. We identified Tula orthohantavirus for the first time in Iran and from Dryomys nitedula sensu lato (s.l.) (Gliridae), a non-muroid host. There are two possible interpretations for this finding: an interspecies spillover or the presence of a broader primary host/reservoir list. However, at present, we do not advocate for either interpretation, but instead, argue for further accumulation of relevant data. Phylogenetic analysis revealed a close relationship between the Tula orthohantavirus identified in this study and those detected in Turkey. Nevertheless, comprehensive field studies, as well as full-length sequence analyses, are required to gain a better understanding of the potential reservoirs, ecology, and epidemiological cycle of the virus in Iran.

Molecular detection and characterization of Anaplasma spp. in cattle and sable antelope from Lusaka and North-Western provinces of Zambia

Rickettsiales of the genus Anaplasma are globally distributed tick-borne pathogens of animals and humans with complex epidemiological cycles. Anaplasmosis is an important livestock disease in Zambia but its epidemiological information is inadequate. This study aimed to detect and characterize the species of Anaplasma present in domestic and wild ruminants in Zambia with a focus on the infection risk posed by the translocation of sable antelope (Hippotragus niger) from North-Western Province to Lusaka Province. Archived DNA samples (n=100) extracted from whole blood (sable n=47, cattle n=53) were screened for Anaplasmataceae using 16S rRNA partial gene amplification followed by species confirmation using phylogenetic analysis. Out of the 100 samples, Anaplasma species were detected in 7% (4/57) of the cattle and 24% (10/43) of the sable antelope samples. Of the 14 positive samples, five were determined to be A. marginale (four from cattle and one from sable), seven were A. ovis (sable) and two were A. platys (sable). Phylogenetic analysis of the 16S rRNA partial gene sequences revealed genetic proximity between A. ovis and A. marginale, regardless of host. The detection of Anaplasma in wildlife in Zambia shows the risk of transmission of Anaplasma species associated with wildlife translocation.