Reovirus infections pose a significant threat to waterfowl health and productivity globally. This review provides a comprehensive update on various aspects of waterfowl reoviruses (WRVs) affecting domestic duck and goose species. We outline the genetic diversity and evolution of circulating strains. The paper details the array of clinical signs and pathologies observed in infected birds. Most advanced laboratory diagnostic methods, including molecular techniques, are reviewed for their role in rapid and accurate detection, forming the cornerstone of effective surveillance programs. Furthermore, we explore the advancements in WRV vaccine development, covering traditional as well as promising novel approaches. The ongoing challenge of managing WRV infections necessitates integrated surveillance-control programs, prioritizing enhanced diagnostic capabilities and the development of more efficacious and broadly protective vaccines to safeguard populations of domestic ducks and geese.

A panel of intestinal samples collected from common pheasants (Phasianus colchicus) between 2008 and 2017 was used for metagenomic investigation using an unbiased enrichment protocol and different bioinformatic pipelines. The number of sequence reads in the metagenomic analysis ranged from 1,419,265 to 17,507,704 with a viral sequence read rate ranging from 0.01% to 59%. When considering the sequence reads of eukaryotic viruses, RNA and DNA viruses were identified in the samples, including but not limited to coronaviruses, reoviruses, parvoviruses, and CRESS DNA viruses (i.e., circular Rep-encoding single-stranded DNA viruses). Partial or nearly complete genome sequences were reconstructed of at least three different parvoviruses (dependoparvovirus, aveparvovirus and chaphamaparvovirus), as well as gyroviruses and diverse CRESS DNA viruses. Generating information of virus diversity will serve as a basis for developing specific diagnostic tools and for structured epidemiological investigations, useful to assess the impact of these novel viruses on animal health.

Reovirus infections in turkeys are associated with arthritis and lameness. Viral genome sequence data are scarce, which makes an accurate description of the viral evolution and epidemiology difficult. In this study, we isolated and characterized turkey reoviruses from Hungary. The isolates were identified in 2016; these isolates were compared with earlier Hungarian turkey reovirus strains and turkey reoviruses isolated in the 2010s in the United States. Gene-wise sequence and phylogenetic analyses identified the cell-receptor binding protein and the main neutralization antigen, σC, to be the most conserved. The most genetically diverse gene was another surface antigen coding gene, μB. This gene was shown to undergo frequent reassortment among chicken and turkey origin reoviruses. Additional reassortment events were found primarily within members of the homologous turkey reovirus clade. Our data showed evidence for low variability among strains isolated from independent outbreaks, a finding that suggests a common source of turkey reoviruses in Hungarian turkey flocks. Given that commercial vaccines are not available, identification of the source of these founder virus strains would permit a more efficient prevention of disease outbreaks before young birds are settled to fattening facilities.

A nem várt események egyik formája az egészségügyi ellátás során végzett téves azonosítás eredményeként előforduló betegcsere, leletcsere. Tapasztalatunk szerint a téves azonosítás és az abból eredő problémák sokkal gyakrabban fordulnak elő, mint amilyen gyakorisággal erről az érintettek jelentést tesznek. A cserék a betegbiztonság szempontjából kiemelt jelentőséggel bírnak a következmények súlyossága miatt, valamint azért, mert egy csere esetén egyszerre akár két beteget is károsodás érhet. Dolgozatunkkal a célunk az volt, hogy a betegcsere és a leletcsere vonatkozásában azonosítsuk a legnagyobb kockázatnak kitett betegcsoportokat, és összegyűjtsük a lehető legtöbb olyan okot, aminek jelentősége lehet a téves azonosításban, valamint azok megelőzési lehetőségeit. A NEVES jelentési rendszer magyar adatbázisába mindössze 3 esetet jelentettek ezen támákban, ez az alacsony esetszám statisztikai elemzést nem tett lehetővé. Hazai gyakorló szakemberek bevonásával szakértői egyeztetéseket folytattunk, áttekintettünk a kapcsolódó legfontosabb szakirodalmakat, és a rendszerezett információk alapján felvázoltuk az oki struktúrát. Meghatároztuk a betegcsere szempontjából kiemelt kockázattal rendelkező csoportokat, összesen 21 ilyen csoportot azonosítottunk. A kutatás eredményeként 10 csoportot alkottunk a betegcseréhez, leletcseréhez vezető általános okokból, ezek a következők: a szabályozás hiányosságai; a munkatársak nem követik a szabályokat; az oktatás hiányosságai; hibás munkafolyamatok; a humánerőforrás problémái; a páciens problémái; a kommunikáció hiányosságai; eszközökkel kapcsolatos problémák; infrastruktúrával kapcsolatos problémák; nem hasznosulnak a korábbi eseményekből szerzett ismeretek/ tapasztalatok. Minden csoporthoz kapcsolódóan ismertetünk megelőzési lehetőségeket az általános ok mögötti gyökérokok függvényében. Kiemelten foglalkozunk a szabályozás témakörével, azon belül is hangsúlyosan az ismeretlen beteg azonosításával, a csere észlelésekor követendő teendőkkel, az adatgyűjtés és a szervezeti kultúra jelentőségével, valamint bemutatunk néhány példát mások működő jógyakorlataiból.

Reovirus infections in reptiles are frequently detected and associated with various clinical diseases; yet, our knowledge about their genetic diversity and evolutionary relationships remains limited. In this study, we characterize at the genomic level five reptile origin orthoreovirus strains isolated from exotic snakes and lizards in Hungary and Germany. The genomic organization of the study strains was similar to that of the representative strains of reptile origin reoviruses belonging to species Reptilian orthoreovirus and Testudine orthoreovirus . Additionally, all five study strains clustered with the bush viper origin reference Reptilian orthoreovirus strain, 47/02. The nucleotide sequence divergence among strains fell from 56.64 to 99.36%. Based on genome segment constellations two well separated groups were observed, which may represent two genetic lineages of reptilian orthoreoviruses we tentatively referred here as genogroups, classifying two squamata origin strains with available whole genome sequences into genogroup I (GGI) and four strains into genogroup II (GGII). The representative GGI and GGII Reptilian orthoreovirus strains are characterized by moderate-to-high nucleotide and amino acid similarities within genogroups (range, 69.45 to 99.36% and 74.64 to 100.00%), whereas lower nucleotide and amino acid similarities (range, 56.64 to 77.24% and 54.53 to 93.85%) and different structures of the bicistronic S1 segment were found between genogroups. Further studies are needed to explore the genomic diversity among reptilian reoviruses of squamata origin; this would be critical to establish a robust classification system for these viruses and to see if interaction among members of distinct lineages may result in viable progenies with novel genetic features.

The concern that the vaccines currently used against Avian orthoreovirus (ARV) infections are less efficient in the field justifies the need for the close monitoring of circulating ARV strains. In this study, we collected necropsy samples from various chicken breeds and tested for ARV by virus isolation, RT-PCR assay and sequence analysis. ARVs were isolated from birds showing runting-stunting syndrome, uneven growth, lameness or increased mortality, with relative detection rates of 38%, 35%, 6% and 25%, respectively. Partial σC gene sequences were determined for nearly 90% of ARV isolates. The isolates could be classified into one of the major genetic clusters. Interestingly, cluster 2 and cluster 5 were isolated from vaccinated broiler breeders, while clusters 1 to 4 were isolated from unvaccinated broilers. The isolates shared less than 75% amino acid identities with the vaccine strains (range, 44.3-74.6%). This study reaffirms the global distribution of the major genetic clusters of ARVs in chicken. The diversity of ARV strains isolated from unvaccinated broilers was greater than those detected from vaccinated animals, however, the relative importance of passive and active immunity on the selection of novel strains in different chicken breeds needs to be better understood.

A betegek eltűnése balesethez vezethet, elesés, sérülés, eltévedés lehet a következménye, ami akár a betegéletét is veszélyeztetheti. Ezért az ilyen események megelőzése fontos megoldandó probléma és kihívás.Az időskori demenciában szenvedő, valamint a pszichiátriai betegek alkotják a betegeltűnések által érintettkét legnagyobb betegcsoportot, közleményünkben velük foglalkozunk. A betegek eltűnésének a demenciában jellemző formáját elkóborlásnak nevezi a szakirodalom.Élesen megkülönböztethető azoktól az esetektől, amikor a pszichiátriai betegek határozott célt követve, sok esetben tiszta tudatállapotban, önkényesen távoznak az ellátó intézményből. Az elkóborlást és az önkényes távozást jelen dolgozatban együttesen a betegeltűnés fogalmával jelöljük.Dolgozatunk célja, hogy az országos NEVES (Nem Várt események) jelentési rendszerbe érkezett adatokelemzéséből kiindulva bemutassuk a fekvőbeteg-ellátásban részesülő betegek eltűnésének, azaz elkóborlásának vagy önkényes távozásának általános okait és az azok megelőzése érdekében hozható intézkedéseket.A jelentett adatok önkéntes és anonim adatszolgáltatás keretében kerültek be az országos adatbázisba, atanulmány elkészítéséhez 133 felnőtt eltűnésének adatait dolgoztuk fel. Az oki kutatás eredményeként 10 csoportot alkottunk az eltűnéshez vezető általános okokból, ezek a következők: a szabályozás hiányosságai; a munkatársak nem követik a szabályokat; kockázatfelmérés hiánya; nem megfelelő kockázatfelmérés; prevenciós eszközök/eljárások alkalmazásának hiánya; nem megfelelő prevenciós módszer alkalmazása; a portaszolgálat nem megfelelő működése; nem megfelelő ellátási környezet; kommunikáció hiányosságai; nem hasznosulnak a korábbi eseményekből szerzett ismeretek/ tapasztalatok.Közleményünkben bemutatjuk, hogy az egyes okok esetében milyen konkrét intézkedések segíthetik a probléma megoldását.

IntroductionAvian reoviruses (ARV), an important pathogen of poultry, have received increasing interest lately due to their widespread occurrence, recognized genetic diversity, and association to defined disease conditions or being present as co-infecting agents. The efficient control measures require the characterization of the available virus strains.MethodsThe present study describes an ARV collection comprising over 200 isolates from diagnostic samples collected over a decade from 34 countries worldwide. One hundred and thirty-six ARV isolates were characterized based on σC sequences.Results and discussionThe samples represented not only arthritis/tenosynovitis and runting-stunting syndrome, but also respiratory symptoms, egg production problems, and undefined disease conditions accompanied with increased mortality, and were obtained from broiler, layer or breeder flocks. In 31 percent of the cases other viral or bacterial agents were demonstrated besides ARV. The most frequent co-infectious agent was infectious bronchitis virus followed by infectious bursal disease virus and adenoviruses. All isolates could be classified in one of the major genetic clusters, although we observed marked discrepancies in the genotyping systems currently in use, a finding that made genotype assignment challenging. Reovirus related clinical symptoms could not be unequivocally connected to any particular virus strains belonging to a specific genetic group, suggesting the lack of strict association between disease forms of ARV infection and the investigated genetic features of ARV strains. Also, large genetic differences were seen between field and vaccine strains. The presented findings reinforce the need to establish a uniform, widely accepted molecular classification scheme for ARV and further, highlight the need for ARV strain identification to support more efficient control measures.

IME – AZ EGÉSZSÉGÜGYI VEZETŐK SZAKLAPJA – TUDOMÁNYOS FOLYÓIRAT XXI. ÉVFOLYAM 2022/4. SZÁM Az egészségügyi ellátás során bekövetkező betegesések megelőzése mind a betegellátás biztonságának javítása, mind pedig az egészségügyi szolgáltatók költségeinek csökkentése szempontjából fontos fejlesztési lehetőség. Dolgozatunk célja, hogy bemutassuk a NEVES jelentési rendszerbe érkezett adatok elemzésére alapozott kutatási eredményeket, amelyek rávilágítanak az egészségügyi szolgáltatóknál bekövetkezett betegesések általános okaira és azok megelőzési lehetőségeire. A NEVES jelentési rendszer indulása óta az adatfeldolgozás megkezdéségig 15 077 betegesési esemény adatait jelentették magyar egészségügyi szolgáltatók anonim, önkéntes módon. Ezeket az adatokat statisztikailag elemeztük, és minőségfejlesztési technikákat is alkalmazva kerestük a bekövetkezésükben szerepet játszó okokat. A vonatkozó szakirodalmak áttekintésével és a szakértői egyeztetésekkel szerzett további ismereteinket is felhasználva rendszereztük a kutatás során azonosított okokat és a megelőzési lehetőségeket. Az okokat 12 fő csoportba soroltuk, amelyek közül kiemelendők a kockázatfelmérés hiánya, a prevenciós intézkedések elmaradása, a kommunikáció hiányosságai és az infrastrukturális problémák. Fontos felhívni a figyelmet arra, hogy ezeket az okokat rendszerben érdemes kezelni. Az eredményes megelőzés érdekében az adott intézményi környezetben minden lehetséges okot fel kell tárni, és minél több ok megszüntetésére törekedve komplex intézkedéseket hozni. Dolgozatunkban felvázoljuk, hogy a be tegesések bekövetkezését előidéző okok azonosításakor milyen konkrét intézkedések segíthetik a megoldást.

A novel gyrovirus was detected in an intestinal specimen of a common pheasant that died due to poult enteritis and mortality syndrome. The genome of the pheasant-associated gyrovirus (PAGyV) is 2353 nucleotides (nt) long and contains putative genes for the VP1, VP2, and VP3 proteins in an arrangement that is typical for gyroviruses. Gyrovirus-specific motifs were identified in both the coding region and the intergenic region of the PAGyV genome. The VP1 of PAGyV shares up to 67.6% pairwise nt sequence identity with reference sequences and forms a distinct branch in the phylogenetic tree. Thus, according to the recently described species demarcation criteria, PAGyV belongs to a novel species in the genus Gyrovirus, family Anelloviridae, for which we propose the name "Gyrovirus phaco 1".

Boid inclusion body disease (BIBD) is a severe and transmissible disease of snakes worldwide. Reptarenaviruses have been identified as the aetiological agents of BIBD. We determined the almost complete genome sequence of an arenavirus detected in a female red-tailed boa that had succumbed in a private collection in Hungary. We used a combination of next generation sequencing and Sanger sequencing methods. Based on the analysis of the obtained sequence data, the virus, tentatively named Coldvalley virus, seemed to belong to the Reptarenavirus genus of the Arenaviridae family. This classification was confirmed by the genome structure (bisegmented single-stranded RNA) characteristic of the genera Mammarenavirus and Reptarenavirus. The pairwise comparison of the nucleotide and amino acid sequences, as well as the topology of the maximum likelihood phylogenetic trees, suggested that the newly-characterised Coldvalley virus can be classified into the species Rotterdam reptarenavirus.

BACKGROUNDLateral flow immunoassays (LFIA) have shown their usefulness for detecting CTX-M- and carbapenemase-producing Enterobacterales (CPEs) in bacterial cultures. Here, we have developed and validated the BL-DetecTool to detect CTX-M enzymes and carbapenemases directly from clinical samples.METHODSThe BL-DetecTool is an LFIA that integrates an easy sample preparation device named SPID (Sampling, Processing, Incubation and Detection). It was evaluated in three University hospitals on urine, blood culture (BC) and rectal swab (RS) specimens either of clinical origin or on spiked samples. RS evaluation was done directly and after a 24 h enrichment step.RESULTSThe CTX-M BL-DetecTool was tested on 485 samples (154 BC, 150 urines, and 181 RS) and revealed a sensitivity and specificity of 97.04% (95% CI 92.59%-99.19%) and 99.43% (95% CI 97.95%-99.93%), respectively. Similarly, the Carba5 BL-DetecTool was tested on 382 samples (145 BC, 116 urines, and 121 RS) and revealed a sensitivity and specificity of 95.3% (95% CI 89.43%-98.47%) and 100% (95% CI 98.67%-100%), respectively. While with the Carba5 BL-DetecTool five false negatives were observed, mostly in RS samples, with the CTX-M BL-DetecTool, in addition to four false-negatives, two false-positives were also observed. Direct testing of RS samples revealed a sensitivity of 78% and 86% for CTX-M and carbapenemase detection, respectively.CONCLUSIONSBL-DetecTool showed excellent biological performance, was easy-to-use, rapid, and could be implemented in any microbiology laboratory around the world, without additional equipment, no need for electricity, nor trained personnel. It offers an attractive alternative to costly molecular methods.

Background: Upper respiratory infections caused by Mycoplasma agassizii have long been known in reptiles, primarily in tortoises. A much smaller number of mycoplasmosis cases have so far been identified in snakes, none of which were caused by M. agassizii. Objectives: In our case, the possibility of mycoplasmosis arose during the pathological/diagnostic testing, which also included a more detailed exploratory microbiological investigation. Materials and methods: The spec men examined, came from a private breeding operation, where snakes were kept in drawer racks, consisting of suitably ventilated boxes measuring 45 x 65 x 20 cm, kept at 27-28 degrees C by day, and 20-21 degrees C at night. The specimen brought to our department for diagnostic tests was a female ball python (Python regius) weighing 1545 g. The snake laid a clutch of egos, typical of the species a month before the examination and started showing respiratory symptoms a few days thereafter. Three weeks later, the animal suddenly died 3 vithout any previous worsening of the symptoms. After the post-mortem examination, we performed histo ogical tests, Mycoplasma culture tests, and PCR tests on samples from various organs. Findings and discussion: Mycoplasma agassizii-like agent were found in the upper and lower respiratory tract, with gravidity and egg-laying increasing susceptibility. The mucous accumulating in the trachea and the lungs, as result of inflammatory processes, caused the suffocation of the animal. In addition to multifocal epithelial proliferation in the lungs, inflammatory cell infiltration was also observed in the trachea. After sequencing, we uploaded the nucleotide sequence of the PCR product of the isolated M. ogassizii-like bacteria to GenBank under reference number MW380903.

Az egészségügyi ellátás során bekövetkező betegesések megelőzése mind a betegellátás biztonságának javítása, mind pedig az egészségügyi szolgáltatók költségeinek csökkentése szempontjából fontos fejlesztési lehetőség. Dolgozatunk célja, hogy bemutassuk a NEVES jelentési rendszerbe érkezett adatok elemzésére alapozott kutatási eredményeket, amelyek rávilágítanak az egészségügyi szolgáltatóknál bekövetkezett betegesések általános okaira és azok megelőzési lehetőségeire. A NEVES jelentési rendszer indulása óta az adatfeldolgozás megkezdéségig 15.077 betegesési esemény adatait jelentették magyar egészségügyi szolgáltatók anonim, önkéntes módon. Ezeket az adatokat statisztikailag elemeztük, és minőségfejlesztési technikákat is alkalmazva kerestük a bekövetkezésükben szerepet játszó okokat. A vonatkozó szakirodalmak áttekintésével és a szakértői egyeztetésekkel szerzett további ismereteinket is felhasználva rendszereztük a kutatás során azonosított okokat és a megelőzési lehetőségeket. Az okokat 12 fő csoportba soroltuk, amelyek közül kiemelendők a kockázatfelmérés hiánya, a prevenciós intézkedések elmaradása, a kommunikáció hiányosságai és az infrastrukturális problémák. Fontos felhívni a figyelmet arra, hogy ezeket az okokat rendszerben érdemes kezelni. Az eredményes megelőzés érdekében az adott intézményi környezetben minden lehetséges okot fel kell tárni, és minél több ok megszüntetésére törekedve komplex intézkedéseket hozni. Dolgozatunkban felvázoljuk, hogy a betegesések bekövetkezését előidéző okok azonosításakor milyen konkrét intézkedések segíthetik a megoldást.

Avian reoviruses are well-known pathogens seriously affecting the productivity of poultry industry. Game birds represent a small segment of the agricultural sector and much remained to be learnt about factors affecting productivity. Here we show that reovirus infections might occur in pheasants and demonstrate that reoviruses of pheasants are of diverse origin. The complete or coding-complete genomic sequences of two Hungarian reovirus strains, D1996/2/1 and Reo/HUN/Pheasant/216/2015, have been determined in this study. The strain D1996/2/1 was isolated in 2012 from birds with gizzard erosion, whereas the other strain was isolated in 2015 from diarrheic pheasant poults. Phylogenetic analyses showed that none of the Hungarian isolates shared common origin with a pheasant reovirus detected recently in the United States. Additionally, we found that Reo/HUN/Pheasant/216/2015 is a multi-reassortant reovirus within the species Avian orthoreovirus that shared genetic relationship with turkey reoviruses (σC), partridge reoviruses (λA, σB), and chicken reoviruses (λB, λC, μA, σA, and σNS), in the respective gene phylogenies, whereas two genes (μB and μNS) did not reveal any possible common ancestors. The other isolate, D1996/2/1, was found to be distantly related to previously described reoviruses raising the possibility that it might represent a novel orthoreovirus species or a new genogroup within the newly accepted species, Neoavian orthoreovirus. The genetic diversity among pheasant reoviruses could raise challenges for virus classification as well as for development of molecular diagnostic tools and vaccine based prevention and control measures.

Avian reoviruses (ARVs) cause serious losses to the poultry industry worldwide. The authors provide a summary about the latest scientific results and research highlights of chicken reoviruses. Avian reovirus can either cause tenosynovitis/ viral arthritis or can join the complex aetiology of a viral enteritis/malabsorption syndrome/runting-stunting syndrome in broiler breeders or in broilers. During the past decade increasing number of tenosynovitis/viral arthrits cases were reported from vaccinated poultry flocks worldwide. Although commercial reovirus vaccines were used with success in the past thirty years, the newly emerging variants of avian reoviruses may escape immunity induced by current vaccine. To prove this hypothesis researchers started to analyse several new variants. The QC protein of the virus is responsible for cell attachment and virus neutralization, therefore this protein is key for developing protective immunity in the host. Researchers began to sequence the oC protein coding gene of new virus isolates and as a result new genotypic clusters have been identified and formed. Most importantly, it was found that emerging new variants shared low genetic similarity with vaccine strains. Considering the possible link between low genetic similarity and low protection level, practitioners turned to custom autogenous vaccines. Selecting the most appropriate strain(s) from diseased cases and use in custom vaccine may lead to induce immunity more specific to the emerging variants. Varying results with custom vaccines and the continuous evolution of ARV pose challenges to current vaccination schemes and prompt the market to seek new vaccination strategies.

A cikkben egy új, innovatív gyorstesztet mutatunk be, mellyel közvetlenül a beteg mintájából ki lehet mutatni a legjelentősebb antibakteriális rezisztenciamechanizmusokat. A francia NG Biotech cég által kifejlesztett eszközt – az Európai Innovációs és Technológiai Intézet (European Institute of Innovation and Technology – EIT Health) által finanszírozott, és Magyarországon a Semmelweis Egyetem, illetve a Dél-Pesti Centrumkórház részvételével zajló – AMR DetecTool projekt keretei között vizsgáljuk és összehasonlítjuk a jelenleg használt standard módszerekkel.

The aim of this review is to summarize the most recent knowledge about reoviruses causing infection and disease in waterfowls. Orthoreoviruses are ubiquitous in ducks and geese. Infection with reovirus can be associated with diseases of the locomotor system, the liver and the immune organs. Waterfowl reoviruses (WRVs) are members of the Avian orthoreovirus species (genus Orthoreovirus), and based on their genetic and biological properties these viruses are grouped into classical and novel type WRVs. Besides these two groups there is a newly emerging genetic clade of WRV, represented by only a few isolates so far. Reovirus infection in waterfowls affects mainly young animals resulting in increased mortality, reduced weight gains and uneven growth rates, and as a consequence WRVs have a significant role in the economic losses of the goose and duck industry. The most common clinical manifestations of the disease are general malaise, diarrhoea and locomotor disorders. Due to the immunosuppressive effect of reoviruses secondary bacterial infections, causing increased mortality, can also occur in diseased birds. The typical hystopathological findings of reovirus infections include lesions in the spleen and the liver, arthritis, fibrinous inflammation of serous membranes and depletion of lymphocytes in the bursa Fabricii. A preliminary diagnosis of reovirus infections can be made on the basis of clinical signs and pathologic lesions, nevertheless subsequent isolation and genetic characterization of the virus is also required. Since there is no commercially available vaccine against WRVs in waterfowl, adequate housing and hygienic conditions are the primary measures to control reovirus infection in waterfowls.

Complete genomic sequences of two orthoreovirus strains, D2533/4/1-10 and D2533/6/1-10, isolated from Pekin ducklings in Germany have been determined. Pairwise sequence comparisons and phylogenetic analyses indicated that strain D2533/4/1-10 might have acquired its genomic segments from three different origins, from classical and novel waterfowl reoviruses, and a yet unknown orthoreovirus strain. D2533/6/1-10 proved to be only distantly related to previously described orthoreoviruses. Reassortment, host species transmission events, and successful adaptation of novel variants may signify a challenge for animal health and maintenance of economic production.

Due to the European measles epidemic and the increased number of imported cases, it can be theorised that the risk of exposure among Hungarian healthcare workers (HCWs) has increased. In 2017, the increased measles circulation in the region led to the emergence of smaller local and hospital epidemics. Therefore, our objective was to determine the herd immunity in the high-risk group of HCWs. A hospital-based study of detecting anti-measles IgG activity was performed in 2017 and included 2167 employees of the Military Medical Centre (Hungary). The screening of HCWs presented a good general seropositivity (90.6%). The highest seroprevalence value (99.1%) was found in the age group of 60 years or older. The lowest number of seropositive individuals was seen in the 41-45 years (86.2%) age group, indicating a significant herd immunity gap between groups. Regarding the Hungarian data, there might be gaps in the seroprevalence of the analysed HCWs, implying that susceptible HCWs may generate healthcare-associated infections. This study suggests that despite the extensive vaccination and high vaccine coverage, it is still important to monitor the level of protective antibodies in HCWs, or in a representative group of the whole population of Hungary, and possibly in other countries as well.