Zagorka Popova | Ss. Cyril & Methodius University in Skopje (original) (raw)

Papers by Zagorka Popova

Macedonian Veterinary Review

Aedes albopictus is an invasive mosquito species spreading throughout Europe and its presence in ... more Aedes albopictus is an invasive mosquito species spreading throughout Europe and its presence in North Macedonia was recorded in 2016. Following the first detection in September 2018, we conducted a two-week mosquito monitoring by ovitraps in order to determine if there were established populations of Aedes albopictus in Skopje, the capital of North Macedonia. Ninety-four Ae. albopictus eggs (0 to 18 eggs per ovitrap per week) were collected from 7 (14%) ovitraps in 3 (30%) municipalities. Thirty-eight eggs (40.4%) successfully hatched and the adult mosquitoes were identified by morphology and PCR. No other potentially invasive species were identified during the monitoring period. Ae. albopictus distribution is expanding and poses a risk for an Aedes-borne disease transmission in North Macedonia. The available data highlight the need for a regular monitoring for tiger mosquitoes to plan adequate control measures.

Acta Veterinaria

Canine monocytic ehrlichiosis (CME) is a widespread, tick-borne, canine disease, caused by an obl... more Canine monocytic ehrlichiosis (CME) is a widespread, tick-borne, canine disease, caused by an obligate intracellular bacterium, Ehrlichia canis. The main vector, a brown-dog tick, Rhipicephalus sanguineus, is widely distributed, especially in areas with tropic, subtropic, or Mediterranean climates (Central and South America, Eastern and Western Asia, Africa, Australia and Southern Europe). The study performed in 2012, by Stefanovska et al., determined a seroprevalence of 18.7% of E. canis among the Macedonian dog population. Up to date, the presence of E. canis, using molecular diagnostic methods, has not been investigated in Macedonia. Therefore, this study aimed to confirm the presence of E. canis, in the pet-dog population on the territory of the city of Skopje, North Macedonia, using a highly sensitive multiplex Real-Time PCR method (qPCR). Whole blood samples from 80 dogs of different breeds and ages, with clinical symptoms of CME and positive serology result for the presence o...

Acta Veterinaria, 2021

Canine monocytic ehrlichiosis (CME) is a widespread, tick-borne, canine disease, caused by an obl... more Canine monocytic ehrlichiosis (CME) is a widespread, tick-borne, canine disease, caused by an obligate intracellular bacterium, Ehrlichia canis. The main vector, a brown-dog tick, Rhipicephalus sanguineus, is widely distributed, especially in areas with tropic, subtropic, or Mediterranean climates (Central and South America, Eastern and Western Asia, Africa, Australia and Southern Europe). The study performed in 2012, by Stefanovska et al., determined a seroprevalence of 18.7% of E. canis among the Macedonian dog population. Up to date, the presence of E. canis, using molecular diagnostic methods, has not been investigated in Macedonia. Therefore, this study aimed to confi rm the presence of E. canis, in the pet-dog population on the territory of the city of Skopje, North Macedonia, using a highly sensitive multiplex Real-Time PCR method (qPCR). Whole blood samples from 80 dogs of different breeds and ages, with clinical symptoms of CME and positive serology result for the presence of antibodies against E.canis, were collected for analyses. Out of 80 dogs, 36 (45%) were found as positive. The present work reports the fi rst molecular detection of E. canis in pet dogs on the territory of the city of Skopje, Macedonia.

Broadening the cross-protection of infectious bronchitis provided by a vaccination regime using t... more Broadening the cross-protection of infectious bronchitis provided by a vaccination regime using three different live infectious bronchitis vaccines

Macedonian Veterinary Review, 2020

Macedonian Veterinary Review, 2015

The study investigated the antimicrobial activity of 13 enterococcal strains (E. faecalis-8, E. f... more The study investigated the antimicrobial activity of 13 enterococcal strains (E. faecalis-8, E. faecium-2, E. hirae-2, E. spp.-1) isolated from our traditional cheeses against pathogen microorganisms. Also, it includes the detection of the following enterocin structural genes: enterocin A, enterocin B, enterocin P, enterocin L50A/B, bacteriocin 31, enterocin AS48, enterocin Q, enterocin EJ97 and cytolysin by using PCR method. All isolates inhibited growth of L. monocytogenes and L.innocua. One isolate had a broader antimicrobial activity. None of the isolates showed inhibitory activity against S. enteritidis, E. coli and Y. enterocolitica. The genes enterocin P, cytolysin and enterocin A were the most frequently detected structural genes among the PCR positive strains. No amplification was obtained in two strains E. faecalis-25 and E. faecalis-86. Three different genes were identified in some strains. With the exclusion of strains possessing a virulence factor, such as cytolysin, producers of more than one enterocins could be of a great technological potential as protective cultures in the cheese industry.

Transboundary and Emerging Diseases, 2020

Bluetongue virus serotype 4 (BTV-4) was confirmed in sheep in North Macedonia in July 2020. The f... more Bluetongue virus serotype 4 (BTV-4) was confirmed in sheep in North Macedonia in July 2020. The full genome of this BTV-4 strain (MKD2020/06) was shown to be most closely related (99.74% nt identity) to the Greek GRE2014/08 and the Hungarian HUN1014 strains, indicating the re-emergence of this BTV serotype in the Balkan region since it was last reported in 2017.

Macedonian Veterinary Review, 2019

Avian avulavirus type 1 (AAvV-1) belongs to the family Paramyxoviridae, genus Avulavirus. Even th... more Avian avulavirus type 1 (AAvV-1) belongs to the family Paramyxoviridae, genus Avulavirus. Even though belonging to a single serotype, there is great genetic variability between these viruses. On the basis of the available complete fusion (F) gene and whole genome sequences and using the genotype classification system, AAvV-1 viruses are divided in two major groups: class I and class II. Class I viruses are predominantly avirulent viruses and majority of the isolations come from waterfowl and domestic poultry from live bird markets in USA and China although isolations from wild birds are reported globally. In our study we used classical, molecular and phylogenetic tools to characterize an AAvV-1 isolated from a mute swan in Macedonia. Based on the complete F gene sequence, we have concluded that the virus designated as AAvV-1/mute swan/Macedonia/546/2012 (KP123431) belongs to the class I of AAvV-1 with an avirulent cleavage site motif 112ERQER*L117. The virus could not be assigned to...

Macedonian Veterinary Review, 2016

Bovine tuberculosis is a chronic infectious disease in cattle caused mainly by Mycobacterium bovi... more Bovine tuberculosis is a chronic infectious disease in cattle caused mainly by Mycobacterium bovis and to a lesser extent by Mycobacterium caprae. The other members of the Mycobacterium tuberculosis complex (MTBC) can also cause the disease in domestic and wild animals and all of them have a zoonotic potential. The main purpose of the study was to determine the presence and distribution of the tuberculous lesions in reactor cattle, and to isolate and identify the causative agents of bovine tuberculosis in the Republic of Macedonia. Lymph nodes and affected organs from 188 reactor cattle slaughtered due to a positive intradermal comparative cervical tuberculin test were analyzed by detection of tuberculous lesions, followed by isolation and molecular identification of the isolated mycobacteria. The isolation was performed on selective media – Lowenstein Jensen with glycerol, Lowenstein Jensen without glycerol and Stonebrink medium supplemented with pyruvate. The molecular identification of the MTBC members was performed by analysis of the Regions of difference (RD1, RD9 and RD4) and detection of single nucleotide polymorphisms in the lepA gene for Mycobacterium caprae. Typical tuberculous lesions were detected in 62 animals (33.0%) and the lesions were most prevalent in the mediastinal lymph nodes (47.5%). The isolated mycobacteria in the MTBC were identified as Mycobacterium bovis and Mycobacterium caprae and were found in both animals with visible lesions (82.2%) and animals without visible lesions (27.7%). The slaughterhouse postmortem examinations and laboratory investigations should be included on regular bases in order to improve the National eradication program.

fi eld gel electrophoresis (PFGE) was also performed as enabling the inspection of epidemiologica... more fi eld gel electrophoresis (PFGE) was also performed as enabling the inspection of epidemiological connections between the obtained isolates. Results and Conclusion: The PFGE analysis showed eight different subtypes of L. monocytogenes. Genotyping did not provide a defi nitive answer on the source of infection. However, the obtained results showed that the silage can be considered as one of the possible, but probably notthe only source of infection for dairy cattle. On the other hand, the farm water couldalso play arole and was possibly contaminated, together with the silage, from the external source (deer) or from the farm source (cattle). As the farm was self-sustaining regarding the herd progeny, the existence of external source of infection is giving a much more plausible explanation. Further investigations of such outbreaks could give additional insightsinto the transmission routes of L. monocytogenes between the environment and ruminants.

The isolation was successful in all fi ve outbreaks resulting in typical colonial morphology for ... more The isolation was successful in all fi ve outbreaks resulting in typical colonial morphology for Listeria. The biochemical identifi cation successfully identifi ed Listeria monocytogenes and Listeria ivanovii subsp. ivanovii and the PCR successfully detected L. monocytogenes. Listeria ivanovii subsp. ivanovii was identifi ed as the causative agent of abortion in sheep and Listeria monocytogenes as causative agent of meningoencephalitis and mortality in sheep and abortions and mortality in goats. Conclusion: This study shows that L. monocytogenes and L. ivanovii subsp. ivanovii are the causative agents of listeriosis in small ruminants in R. Macedonia. The implemented diagnostic protocols successfully identifi ed the two pathogenic species of Listeria. Additional investigations should be made in order to identify the strains circulating in R. Macedonia and their possible connection.

Partial sequencing reveals the existence of one BTV-4 strain on whole territory of Macedonia duri... more Partial sequencing reveals the existence of one BTV-4 strain on whole territory of Macedonia during 2014 outbreak

Zagorka Popova*1, Kiril Krstevski1, Igor Dzadzovski1, Aleksandar Janevski1, Dine Mitrov1, Slavcho Mrenoshki1, Iskra Cvetkovikj1, Aleksandar Dodovski1

1 Veterinary Institute, Faculty of Veterinary Medicine, University “Ss. Cyril and Methodius” Skopje, Macedonia

Abstract
Introduction: Bluetongue (BT) is non-contagious, insect-borne, disease of ruminants caused by bluetongue virus (BTV). BTV is transmitted between susceptible animals by some species of Culicoides midges. The disease has major international significance and economic impact. Since 1998 BTV become frequently present in different parts of European continent, causing few wide epidemics. First occurrence of bluetongue in Macedonia was recorded in 2001, with clinical cases in sheep throughout the country. BT reoccurred in July 2014 when whole country was a part of the big BT epidemics in the Balkans. Out of 26 officially recognized BTV serotypes, only serotype 9 and serotype 4 have been confirmed in Macedonia.
The purpose of this research was to clarify and better understand the molecular epidemiology of the disease and the possible presence of different BTV serotypes on the territory of Macedonia.
Materials and methods: EDTA treated blood from sheep with clinical signs was used for detection of BTV RNA using Pan BTV real time RT PCR (Touissaint et al. (2007). Total RNA was isolated with QIAmp Viral RNA Mini Kit (Qiagen) according to manufacturer’s instruction. Positive samples were further tested with serotype 4 - specific conventional RT-PCR which targets segment-2 of the viral RNA. Reverse transcription and PCR step were performed with Qiagen One Step RT PCR kit. A selection of 24 BTV-4 positive samples from 20 municipalities was sequenced using Big Dye Terminator v.3.1 Cycle Sequencing kit (Applied Biosystems). Raw sequence data was edited in BioEdit and sequences alignment was performed in MEGA 6.
Results: Nucleotide similarity analysis, querying nucleotide data available in GenBank, confirmed that all nucleotide sequences are part of BTV-4 genome and showed 100% similarity with BTV -4 strain (KP268815) isolated in Hungary in 2014. Twenty two nucleotide sequences were identical and only two sequences had the same nucleotide mutation (A-G) at position 631.
Conclusion: Macedonia experienced severe BTV outbreak during 2014 which had great direct and indirect economic impact, especially in sheep production. The epidemics in 2014 present a first, officially recorded, introduction of BTV-4 in Macedonia, which spread across the whole country within one month. Based on nucleotide data from partial sequencing of Segment 2, we have concluded that the same BTV-4 strain is present all over the country. This implied that the outbreaks had same origin and were appearing as a result of the infection spreading wave.

Conference Presentations by Zagorka Popova

Preliminary testing of commercial flocks using molecular and phylogenetic analysis revealed prese... more Preliminary testing of commercial flocks using molecular and phylogenetic analysis revealed presence of genotypes QX and 4/91 in poultry farms with clinical signs and in poultry farms without clinical signs. Poultry farms are performing different vaccination programs without the knowledge of the genotype of the circulating strains. The purpose of this study was to detect presence of IBV in commercial flocks in Macedonia by molecular methods and to genotype the detected strains thus to establish a map of circulating genotypes in the country.

Avian infectious bronchitis (IB) is an acute and highly contagious disease caused by the avian in... more Avian infectious bronchitis (IB) is an acute and highly contagious disease caused by the avian infectious bronchitis virus (IBV). IBV is a gammacoronavirus of the family Coronaviridae causing respiratory disease in chickens of all ages and loss of production and egg quality in laying hens. The major problem in the control of IB is the ability of the virus to generate antigenic variants, due to mutation or sometimes recombination of the S1 spike gene. The S1 spike protein, located on the surface of the viral membrane is responsible for virus binding and entry into host cells. A molecular survey performed in commercial layer flocks revealed presence and circulation of the following genotypes GI-13 (4/91), GI-21 (Italy-02), GI-19 (QX), GI-1 (Mass) and GI-12 (D274). The purpose of this study was to check if there is occurrence of recombination between the IBV genotypes present in Macedonia. For this study we used full sequences of the S1 gene from previously characterized samples, collected during the molecular survey performed throughout the country. The alignment was performed with slow iterative refinement method (FFT-NS-i) in Mafft v.7.0. For the recombination analysis we used RDP4 v.4.80. The sequences suspected to be recombinant were divided in two parts according to the results from the recombination analysis and two maximum likelihood trees were performed in PhyML v 3.0 for confirmation. Two of the isolates were suspected for recombination but only one isolate was confirmed. The recombination occurred between GI-1 (Mass) and GI-13 (4/91) genotypes. Both genotypes are used as vaccines in the country. Moreover, this recombinant virus was isolated in the area where all five genotypes were present. Because of the ability of this virus for mutation and recombination in field conditions new recombinant strains emerge. Sometimes they disappear but sometimes they lead to new genotypes or strains with new features. Therefore, in situation when grouping on the phylogenetic tree of the particular virus is not clear recombination analysis should be performed. To maximize the protection against this disease it is necessary to know which genotypes are circulating in a specific area and in a specific time period. Thus, a proper vaccination program can be developed.

Macedonian Veterinary Review

Acta Veterinaria

Acta Veterinaria, 2021

Canine monocytic ehrlichiosis (CME) is a widespread, tick-borne, canine disease, caused by an obl... more Canine monocytic ehrlichiosis (CME) is a widespread, tick-borne, canine disease, caused by an obligate intracellular bacterium, Ehrlichia canis. The main vector, a brown-dog tick, Rhipicephalus sanguineus, is widely distributed, especially in areas with tropic, subtropic, or Mediterranean climates (Central and South America, Eastern and Western Asia, Africa, Australia and Southern Europe). The study performed in 2012, by Stefanovska et al., determined a seroprevalence of 18.7% of E. canis among the Macedonian dog population. Up to date, the presence of E. canis, using molecular diagnostic methods, has not been investigated in Macedonia. Therefore, this study aimed to confi rm the presence of E. canis, in the pet-dog population on the territory of the city of Skopje, North Macedonia, using a highly sensitive multiplex Real-Time PCR method (qPCR). Whole blood samples from 80 dogs of different breeds and ages, with clinical symptoms of CME and positive serology result for the presence of antibodies against E.canis, were collected for analyses. Out of 80 dogs, 36 (45%) were found as positive. The present work reports the fi rst molecular detection of E. canis in pet dogs on the territory of the city of Skopje, Macedonia.

Macedonian Veterinary Review, 2020

Macedonian Veterinary Review, 2015

Transboundary and Emerging Diseases, 2020

Macedonian Veterinary Review, 2019

Macedonian Veterinary Review, 2016

Zagorka Popova*1, Kiril Krstevski1, Igor Dzadzovski1, Aleksandar Janevski1, Dine Mitrov1, Slavcho Mrenoshki1, Iskra Cvetkovikj1, Aleksandar Dodovski1

1 Veterinary Institute, Faculty of Veterinary Medicine, University “Ss. Cyril and Methodius” Skopje, Macedonia