ABSTRACT
Hepatitis E virus (HEV) genotype 3 is the most prevalent HEV genotype in Europe causing mostly asymptomatic infections in humans, but can also sporadically cause severe acute hepatitis, chronic liver disease, chronic hepatitis in immunocompromised patients and extra-hepatic manifestations. Although much is today known about the swine reservoir, no information is available on the occurrence of HEV from widely distributed deer species in Portugal. Here, we investigated the presence and characterized HEV in free-living deer in Portugal by screening stools from red deer (Cervus elaphus) (n = 95) and fallow deer (Dama dama) (n = 35) for HEV by a broad-spectrum nested RT-PCR, followed by sequencing and phylogenetic analysis. Two red deer females, sampled in central Portugal, showed to be shedding HEV (2.1%; 95% confidence interval: 0.58-7.35). Sequencing and genetic characterization showed that these two deer HEV sequences were 98.96% identical to each other, being both of HEV genotype 3 subgenotype 3e. The increasing numbers and distribution of deer in Portugal and the zoonotic features of the circulating HEV genotype 3 subgenotype 3e highlights the importance of continued surveillance directed to food-borne diseases, especially those involving wild animals and deer in particular.
Subject(s)
Deer , Hepatitis E virus , Hepatitis E , Swine Diseases , Animals , Female , Genotype , Hepatitis E/epidemiology , Hepatitis E/veterinary , Hepatitis E virus/genetics , Humans , Phylogeny , Portugal/epidemiology , SwineABSTRACT
INTRODUCTION: Norovirus outbreaks frequently occur in communities and institutional settings acquiring a particular significance in armed forces where prompt reporting is critical. Here we describe the epidemiological, clinical and laboratorial investigation of a multicentre gastroenteritis outbreak that was detected simultaneously in three Portuguese army units with a common food supplier, Lisbon region, between 5 and 6 December 2017. METHODS: Questionnaires were distributed to all soldiers stationed in the three affected army units, and stool specimens were collected from soldiers with acute gastrointestinal illness. Stool specimens were tested for common enteropathogenic bacteria by standard methods and screened for a panel of enteric viruses using a multiplex real-time PCR assay. Food samples were also collected for microbiological analysis. Positive stool specimens for norovirus were further genotyped. RESULTS: The three simultaneous acute gastroenteritis outbreaks affected a 31 (3.5%) soldiers from a total of 874 stationed at the three units and lasted for 2 days. No secondary cases were reported. Stool specimens (N=11) were negative for all studied enteropathogenic agents but tested positive for norovirus. The recombinant norovirus GII.P16-GII.4 Sydney was identified in all positive samples with 100% identity. CONCLUSIONS: The results are suggestive of a common source of infection plausibly related to the food supplying chain. Although centralisation of food supplying in the army has economic advantages, it may contribute to the multifocal occurrence of outbreaks. A rapid intervention is key in the mitigation of outbreak consequences and in reducing secondary transmission.
Subject(s)
Disease Outbreaks/statistics & numerical data , Military Facilities/statistics & numerical data , Military Personnel/statistics & numerical data , Caliciviridae Infections/epidemiology , Feces/virology , Food Quality , Gastroenteritis/epidemiology , Gastroenteritis/virology , Humans , Norovirus/drug effects , Norovirus/pathogenicity , Portugal/epidemiology , Surveys and QuestionnairesABSTRACT
INTRODUCTION: Norovirus gastroenteritis is one of the most frequent causes of personnel unavailability in military units, being associated with significant morbidity and degradation of their operational effectiveness. The disease is usually mild but can be severe and life-threatening in young and healthy soldiers, who are prone to dehydration due to intensive daily activity. Despite its impact, the full extent of the norovirus gastroenteritis burden in military forces remains unclear. This systematic review aims to evaluate the impact and ascertain clinical and epidemiological features of norovirus outbreaks that have occurred in the military forces. METHODS: The systematic review followed the Preferred Reporting Items for Systemic Reviews and Meta-Analysis (PRISMA) guidelines and used three databases: PubMed, Scopus, and LILACs. Papers published up to 1 September 2019 were included without restrictions if they reported one or more outbreaks in the military forces on active duty, either on national territories or deployed overseas. RESULTS: A total of 343 papers were retrieved from the literature search. After inclusion/exclusion criteria a total of 39 eligible papers were considered. From 1988 (first reported outbreak in the military) to 2018 more than 101 norovirus outbreaks have been reported in the military, accounting for at least 24 332 cases. Secondary transmission was emphasised as the main route of norovirus transmission in the military forces, with eating outside the military setting an important route for the primary cases. CONCLUSIONS: The present review highlights that norovirus gastroenteritis has been a burden to military troops both in combat and on peacekeeping operations. Norovirus disease has been shown to exact a substantial toll on mission readiness and operational effectiveness. It is noteworthy that the impact of norovirus outbreaks among military units is underestimated because the literature review retrieved information from the armed forces from only nine countries.
Subject(s)
Caliciviridae Infections/complications , Disease Outbreaks/prevention & control , Military Medicine/methods , Caliciviridae Infections/epidemiology , Caliciviridae Infections/transmission , Humans , Military Medicine/trends , Military Personnel , Norovirus/drug effects , Norovirus/pathogenicityABSTRACT
Crenosoma striatum is a host-specifi c metastrongiloid nematode causing respiratory tract disease in hedgehogs (Erinaceus europaeus). Since few studies have reported C. striatum in hedgehogs and little genetic data is available concerning this lungworm, this study aimed to determine the occurrence of C. striatum in a population sample of hedgehogs from Portugal, additionally providing morphological, histological and molecular data. From 2017 to 2018 a survey of infection was carried out in 11 necropsied hedgehogs. Worms were extracted from fresh lung tissues and microscopically evaluated. Molecular characterization of partial mitochondrial (12S rRNA) and nuclear (18S rRNA) genes was performed. The presence of lungworms in pulmonary tissues of five hedgehogs (45.5%) was detected. Morphological and histopathological analyses evidenced adult forms of nematodes consistent with C. striatum. Molecular characterization of 18S rRNA genes confirmed the classifi cation as C. striatum. Also, novel genetic data characterizing the mitochondrial (12S rRNA) gene of C. striatum is presented. This is the first report of C. striatum infection in hedgehogs of Portugal. The findings here reported provide new insights regarding the geographic distribution and the molecular identification of this lungworm species.
ABSTRACT
INTRODUCTION: Gastrointestinal infections are among the most common foodborne and waterborne diseases in military populations, with direct implications in operational efficiency and force readiness. Through the surveillance system of reportable acute gastrointestinal illness in the Portuguese Army, four norovirus outbreaks were identified between October 2015 and October 2017 in mainland Portugal and the Azores archipelago. The present study documents the epidemiological, clinical and laboratory investigations of these norovirus outbreaks. METHODS: Cases were investigated and epidemiological questionnaires were distributed to all soldiers in each military setting where the outbreaks occurred. Stool samples from soldiers with acute gastroenteritis illness were collected and screened for common enteropathogenic agents. Food and water samples served on the settings were also collected for microbiological investigation. Norovirus-positive samples were further characterised by sequence analysis using a public automated genotyping tool. RESULTS: The four outbreaks affected a total of 99 soldiers among the 618 stationed on base units and in a military exercise. A total of 27 soldiers provided a stool sample, of which 20 were positive for norovirus by real-time PCR. Phylogenetic analysis showed that the noroviruses involved were all genogroup II, namely GII.17, GII.Pe-GII.4 Sydney 2012, GII.P2-GII.2 and GII.P16-GII.2. Of note, 30 soldiers had to receive treatment at the military hospital due to severity of symptoms. CONCLUSION: In this short, two-year surveillance period, a total of four norovirus gastroenteritis outbreaks were detected in the Portuguese Army which caused a considerable morbidity, showing once again the impact of norovirus on Army effectiveness and force readiness.
Subject(s)
Caliciviridae Infections/epidemiology , Gastroenteritis/virology , Military Personnel/statistics & numerical data , Norovirus , Disease Outbreaks , Feces/virology , Gastroenteritis/epidemiology , Genotype , Humans , Norovirus/genetics , Population Surveillance , Portugal/epidemiologyABSTRACT
A few years after the initial 2011 large scale Schmallenberg virus (SBV) epidemic that affected Europe, a subsequent decrease in new SBV infections was observed presumably associated with natural substitution of previously exposed animals. In the present work, a 2-year prospective serosurvey was performed to evaluate SBV circulation in a population of sheep living at high altitude in the central region of Portugal and with restricted movement. Blood from a representative sample of 168 autochthonous sheep was collected in 2015 and again in 2016, and tested for the presence of anti-SBV IgG by ELISA. Of the 2015 sample collection, seven animals tested positive for anti-SBV IgG, corresponding to a seroprevalence of 4.2% while of the 2016 sample collection, 10 presented SBV antibodies, showing a seroprevalence of 6.0% (p = 0.619). Results show that SBV is endemic in sheep of central Portugal, even in herds at high altitude locations. When comparing anti-SBV seroprevalences of 2015/2016 found in this study, to one detected in 2014 in the same region, a steep decrease could be observed (p < 0.001). This is in accordance with what has been documented in Western European countries, where a decrease in the number of SBV-infected sheep has been found, a fact which may pose a new threat for SBV re-emergence.
Subject(s)
Antibodies, Viral/blood , Bunyaviridae Infections/veterinary , Orthobunyavirus/immunology , Sheep Diseases/virology , Altitude , Animals , Bunyaviridae Infections/immunology , Bunyaviridae Infections/virology , Enzyme-Linked Immunosorbent Assay/veterinary , Immunoglobulin G/blood , Portugal , Prospective Studies , Seroepidemiologic Studies , Sheep , Sheep Diseases/immunologyABSTRACT
This study evaluated the impact of maternal vaccination against rubella on the levels of specific rubella IgG (rIgG) in 198 newborn cord sera samples. Detailed maternal vaccination data were available. Specific rIgG was measured using a commercial enzyme immunoassay. Most mothers (78.8%) had been vaccinated against rubella at least once in their lives. In 15 (7.6%) cord sera samples, the concentration of specific rIgG was below 11 IU/ml, which was classified as seronegative. Statistical analysis using multiple logistic regression (n = 198) showed that newborns of mothers born between 1986 and 1995, and those born to unvaccinated mothers, were more likely to be seronegative (odds ratio (ORs) 5.2 and 4.9, respectively, adjusted for sex and gestational age). For vaccinated mothers (n = 156), those born between 1986 and 1995 were more likely to have seronegative newborns (OR 11.5 adjusting for sex, gestational age and time since last vaccination). Mothers of the 15 (7.6%) seronegative newborns might have been susceptible to rubella during pregnancy. Checking the vaccination status therefore recommended.
Subject(s)
Antibodies, Viral/blood , Fetal Blood/chemistry , Immunoglobulin G/blood , Rubella Vaccine/immunology , Rubella/immunology , Rubella/prevention & control , Vaccination/statistics & numerical data , Adolescent , Adult , Age Factors , Female , Humans , Immunoenzyme Techniques , Male , Maternal Age , Middle Aged , Mothers/statistics & numerical data , Portugal , Rubella/virology , Young AdultABSTRACT
The concept of zoonotic hepatitis E in industrialized countries has emerged with the discovery of swine strains of hepatitis E virus (HEV) genotype 3, closely related to human HEV. Different routes of zoonotic HEV transmission have been recognized, including contact with infected pigs. Workers occupationally exposed to swine (WOES) have been considered a risk group for HEV infection, but contradictory results have been reported. In the present study, we searched for anti-HEV IgG in WOES (butchers, slaughterhouse workers, veterinarians and pig farmers; n = 114) and in the general population (n = 804) in order to investigate the potential occupational risk of zoonotic HEV infection in this work group. A significantly higher (p = 0.008) anti-HEV IgG seroprevalence was found in WOES (30.7 %) when compared with the general population (19.9 %). Multivariate analysis showed that having professions with exposure to pigs for more than 16.5 years was a risk factor for being positive for anti-HEV IgG (aOR of 5.4, 95 % CI 1.9-15.6, p = 0.002). To our knowledge, this is the first study on the prevalence of anti-HEV IgG in WOES in Portugal, also showing increased probability for infection in this group.
Subject(s)
Animal Husbandry , Hepatitis Antibodies/blood , Hepatitis E virus/immunology , Hepatitis E/epidemiology , Occupational Exposure , Adult , Aged , Aged, 80 and over , Animals , Female , Humans , Immunoglobulin G/blood , Male , Middle Aged , Portugal , Seroepidemiologic Studies , Swine , Young AdultABSTRACT
In Portugal, the recommended age for the second dose of MMR (MMR2) was changed from 10-13 years to 5-6 years for those born in 1994 and afterwards. This study aimed to assess if MMR schedule and time elapsed from the last dose are associated with the concentration of rubella and mumps IgG antibodies. Three Portuguese birth cohorts (convenience samples) were selected for this study (66, 59 and 41 participants born respectively in 1990-1993, 1994-1995 and 2001-2003). Geometric mean concentrations (GMC) for mumps IgG were respectively 36, 30 and 38 RU/ml (P = 0·236) and for rubella IgG were 18, 20 and 17 IU/ml (P = 0·641). For both specific antibodies, no differences were observed with time since MMR2. Receiving MMR2 at 5-6 or 10-13 years was not associated with concentration of both antibodies. The GMC of rubella IgG was lower in males (P = 0·029). Taking into account previous evidence and the logistics needed to change vaccination schedules, it seems reasonable that sustaining very high coverage with two doses of MMR is currently the most pragmatic way to control mumps and rubella rather than any changes to the schedule.
Subject(s)
Immunization Schedule , Immunogenicity, Vaccine , Measles-Mumps-Rubella Vaccine/administration & dosage , Mumps virus/immunology , Rubella virus/immunology , Adolescent , Antibodies, Viral/blood , Child , Child, Preschool , Cohort Studies , Humans , Mumps/prevention & control , Mumps/virology , Portugal , Rubella/prevention & control , Rubella/virologyABSTRACT
Hepatitis E virus (HEV) is a zoonotic agent today considered a major Public Health issue in industrialized countries. HEV strains belonging to zoonotic genotype 3 are widely present in swine, being today considered important reservoirs for human disease. Unlike in swine, only scarce data are available on the circulation of HEV in wild boar. This study describes the detection and molecular characterization of HEV in livers from sylvatic wild boar hunted in Portugal and destined for consumption. Additionally, the detection of HEV in stools of a confined wild boar population also destined for consumption is also described. A total of 80 liver samples collected during the hunting season of 2011/2012 and 40 stools collected in February 2012 from a wild boar breeding farm in Portugal were tested by a nested broad-spectrum RT-PCR assay targeting open reading frame (ORF) 1. Twenty livers (25.0%) and 4 stools (10%) were positive for HEV. Phylogenetic analysis showed that all strains clustered with sequences classified as HEV genotype 3 subgenotype e. To our knowledge, this is the first report documenting the occurrence and molecular analysis of HEV in sylvatic and captive wild boar destined for human consumption in Portugal. This report demonstrates for the first time the circulation of HEV in wildlife reservoirs of Portugal adding knowledge to the epidemiology of HEV in wild boar populations.
Subject(s)
Hepatitis E virus/genetics , Hepatitis E virus/isolation & purification , Hepatitis E/epidemiology , Swine Diseases/epidemiology , Animals , Animals, Wild/virology , Feces/virology , Genotype , Liver/virology , Phylogeny , Portugal/epidemiology , Swine/virology , Swine Diseases/virologyABSTRACT
Despite the growing importance of hepatitis E virus (HEV) in industrialized countries, minimal attention has been given to autochthonous HEV infection in children. The present study screened archived sera (N = 71) from a Portuguese pediatric cohort collected in 1992-1995 for the presence of antibodies against HEV, using enzyme immunoassays and immunodot. Anti-HEV IgG was detected in two children and anti-HEV IgM in one, suggesting an acute HEV infection. This shows that HEV was circulating in the paediatric population of Portugal in the early 1990s.
Subject(s)
Hepatitis E/epidemiology , Adolescent , Child , Child, Preschool , Cohort Studies , Enzyme-Linked Immunosorbent Assay , Female , Hepatitis Antibodies/blood , Hepatitis E virus/immunology , Humans , Immunoblotting , Immunoglobulin G/blood , Immunoglobulin M/blood , Infant , Male , Portugal/epidemiology , Seroepidemiologic StudiesABSTRACT
An outbreak of porcine epidemic diarrhea virus (PEDV) in the South of Portugal in January 2015 and the spread of PEDV northwards in the territory are described. Comparative analysis of the amplified sequences showed a very high (99.0%) identity with the PEDV variant most recently reported in the United States and also show complete (100%) identity to the strains recently reported in Germany, supporting the hypothesis that a unique strain is currently circulating in Europe. The origin of this PEDV variant still needs to be elucidated and further studies in the remaining European countries may contribute to the knowledge.
Subject(s)
Coronavirus Infections/veterinary , Disease Outbreaks/veterinary , Porcine epidemic diarrhea virus/isolation & purification , Swine Diseases/virology , Animals , Coronavirus Infections/epidemiology , Coronavirus Infections/virology , Molecular Sequence Data , Portugal/epidemiology , Swine , Swine Diseases/epidemiology , United StatesABSTRACT
This report presents the results of the national surveillance system of diarrhea etiology of the National Institute of Health of Portugal concerning norovirus (NoV) during a two-year period, May 2011-2013. Of the total 580 stool samples collected from patients hospitalized for acute diarrhea in 13 Hospitals of Portugal, 67 (11.6%) tested positive for NoV. From May 2011 to March 2012 the GII.4 variant New Orleans 2009 was the most predominant strain having been replaced by the new GII.4 variant Sydney 2012 since then till the end of the survey. To our knowledge this is the first study showing the circulation of GII.4 as the norovirus strain most commonly associated to gastroenteritis and the first to report the replacement of GII.4 New Orleans by GII.4 Sydney 2012 variant in Portugal.
Subject(s)
Caliciviridae Infections/epidemiology , Caliciviridae Infections/virology , Diarrhea/epidemiology , Diarrhea/virology , Genetic Variation , Norovirus/genetics , Population Surveillance , Caliciviridae Infections/history , Diarrhea/history , Genotype , History, 21st Century , Hospitalization , Humans , Norovirus/classification , Norovirus/isolation & purification , Portugal/epidemiologyABSTRACT
The discovery of autochthonous hepatitis E in industrialized countries associated to genotype 3 has changed substantially the understanding about hepatitis E virus (HEV) circulation. In these countries transmission has been associated to the consumption and direct contact to swine, a well-known reservoir for HEV. More animal reservoirs for HEV might exist since antibodies to HEV have been detected in other animal species, such as dogs and cats. Given the intimate contact between these pets and humans, the potential zoonotic HEV transmission from dogs and cats deserves to be explored. To address this issue, 493 sera from pet veterinarians (373) and matched general population (120) were tested for the presence of anti-HEV IgG using a commercial ELISA. Antibodies to HEV were found in 9.9% veterinarians and 13.3% general population. No statistically significant difference was found between these two groups showing that pet veterinarians have no increased risk to hepatitis E compared to the general population.
Subject(s)
Hepatitis E/epidemiology , Occupational Exposure , Pets , Veterinarians , Adult , Animals , Cats , Dogs , Enzyme-Linked Immunosorbent Assay , Female , Hepatitis Antibodies/blood , Humans , Immunoglobulin G/blood , Male , Middle Aged , Risk Assessment , Seroepidemiologic Studies , Young AdultABSTRACT
Autochthonous hepatitis E virus (HEV) infection has been increasingly reported in Europe and the United States, mostly arising from genotype 3 and less frequently genotype 4. We report here on a patient with HEV genotype 3a infection complicated by Guillain-Barré syndrome in Portugal in December 2012. We draw attention to the diagnosis of autochthonous HEV infection and to its rare, but important, neurological complications.
Subject(s)
Guillain-Barre Syndrome/complications , Hepatitis E virus/isolation & purification , Hepatitis E/complications , Adult , Female , Guillain-Barre Syndrome/diagnosis , Hepatitis E/diagnosis , Hepatitis E virus/genetics , Humans , Polymerase Chain Reaction , Portugal , RNA, Viral/blood , Treatment OutcomeABSTRACT
The high mortality of pregnant women is one of the main features of hepatitis E virus (HEV) infection in endemic countries. With the emergence of genotype 3 HEV in industrialized countries, attention should be given to pregnant women from these regions since the effect of genotype 3 HEV in pregnancy is not yet known. In this study, archived sera dating from 1993 from mothers with no history of traveling to HEV endemic countries and their newborns were tested for anti-HEV IgG antibodies. Four of the 12 maternal sera were positive for IgG anti-HEV, indicating exposure to this virus. Their newborns were also positive, showing higher anti-HEV IgG levels. Overall, these findings demonstrate not only an efficient transplacental transport of anti-HEV IgG, but also circulation of autochthonous HEV in Portugal in the early 1990s.
Subject(s)
Hepatitis Antibodies/blood , Hepatitis E virus/immunology , Hepatitis E/epidemiology , Hepatitis E/transmission , Infectious Disease Transmission, Vertical , Adolescent , Adult , Female , Humans , Immunoglobulin G/blood , Infant, Newborn , Mothers , Portugal/epidemiology , Pregnancy , Young AdultABSTRACT
This study evaluated the in vitro interaction between ciprofloxacin (CIP) and classical antifungals against Histoplasma capsulatum var. capsulatum in mycelial (n = 16) and yeast-like forms (n = 9) and Coccidioides posadasii in mycelial form (n = 16). This research was conducted through broth microdilution and macrodilution, according to Clinical Laboratory Standards Institute. Inocula were prepared to obtain from 0.5 × 10(3) to 2.5 × 10(4) cfu ml(-1) for H. capsulatum and from 10(3) to 5 × 10(3) cfu ml(-1) for C. posadasii. Initially, minimum inhibitory concentration (MIC) for each drug alone was determined. Then, these MICs were used as the highest concentration for each drug during combination assays. The procedures were performed in duplicate. For all combination assays, MICs were defined as the lowest concentration capable of inhibiting 80% of visible fungal growth, when compared to the drug-free control. Drug interaction was evaluated by paired sample t-Student test. The obtained data showed a significant MIC reduction for most tested combinations of CIP with antifungals, except for that of CIP and voriconazole against yeast-like H. capsulatum. This study brings potential alternatives for the treatment of histoplasmosis and coccidioidomycosis, raising the possibility of using CIP as an adjuvant antifungal therapy, providing perspectives to delineate in vivo studies.
Subject(s)
Antifungal Agents/pharmacology , Ciprofloxacin/pharmacology , Coccidioides/drug effects , Histoplasma/drug effects , Caspofungin , Coccidioides/growth & development , Drug Evaluation, Preclinical , Drug Synergism , Echinocandins/pharmacology , Histoplasma/growth & development , Lipopeptides , Microbial Sensitivity Tests , Mycelium/drug effects , Pyrimidines/pharmacology , Triazoles/pharmacology , VoriconazoleABSTRACT
The effects of the protease inhibitors saquinavir, darunavir, ritonavir, and indinavir on growth inhibition, protease and phospholipase activities, as well as capsule thickness of Cryptococcus neoformans were investigated. Viral protease inhibitors did not reduce fungal growth when tested in concentrations ranging from 0.001 to 1.000 mg/L. A tendency toward increasing phospholipase activity was observed with the highest tested drug concentration in a strain-specific pattern. However, these drugs reduced protease activity as well as capsule production. Our results confirm a previous finding that antiretroviral drugs affect the production of important virulence factors of C. neoformans.
Subject(s)
Anti-Retroviral Agents/pharmacology , Cryptococcus neoformans/drug effects , Gene Expression Regulation, Fungal/drug effects , Protease Inhibitors/pharmacology , Cryptococcus neoformans/enzymology , Cryptococcus neoformans/pathogenicity , Indinavir/pharmacology , Ritonavir/pharmacology , Saquinavir/pharmacology , Virulence Factors/geneticsABSTRACT
This study represents the primary hepatitis E virus (HEV) surveillance in domestic pigs in Portugal, five pig farms were investigated in 5 different Portuguese regions, ten faecal samples were collected at four different stages of the production. All faecal samples were tested for hepatitis E virus by real-time RT-PCR. At least one sample from each farms of all age groups tested positive for HEV. The prevalence in the pig herds varied from 10% to 30% and the mean prevalence was 32% in weaners, 20% in growers, 32% in fatteners and 4% in adult dry sows. Phylogenetic analysis of the detected HEV sequences indicated that the circulating virus strains belong under the genotype 3.
Subject(s)
Hepatitis E virus/isolation & purification , Hepatitis E/veterinary , Swine Diseases/epidemiology , Age Distribution , Animals , Feces/virology , Female , Genotype , Hepatitis E/epidemiology , Hepatitis E/genetics , Hepatitis E/virology , Hepatitis E virus/classification , Hepatitis E virus/genetics , Male , Phylogeny , Portugal/epidemiology , Prevalence , RNA, Viral/genetics , RNA, Viral/isolation & purification , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNA , Sus scrofa , Swine , Swine Diseases/genetics , Swine Diseases/virology , ZoonosesABSTRACT
A slow growing skin tumour was identified on the head of a 6-year-old male Serra da Estrela black sheep. The animal had no previous history of exposure to ultraviolet radiation or illness. The tumour consisted of an irregular mass subdivided into two polypoid regions and there were small alternating pigmented and non-pigmented areas in the surrounding epidermis. Microscopical and immunohistochemical features were consistent with a melanocytic tumour of the melanocytoma type, without signs of vascular or perineural invasion. The tumour cells contained pigment stained by the Masson Fontana reaction, expressed S100 protein and vimentin and displayed a low proliferative rate (Ki67 labelling <1%). No metastases were found at the time of gross necropsy examination. Analyses of the homologous regions of the hot spot mutational exons of BRAF and NRAS (the genes that are most often mutated in human melanocytic tumours) did not reveal alterations, but there were silent polymorphic variations in these genes. No such variation was observed in the GNAQ gene sequence that is mutated in human melanocytomas.