Development of an indirect ELISA against Orf virus using two recombinant antigens, partial B2L and F1L

Orf is a highly contagious viral disease affecting goats and sheep. It is caused by Orf virus (ORFV) and has caused severe economic losses to the global goat industry, including in China. In this study, an indirect ELISA method for recombinant proteins based on truncated dominant antigenic epitopes of B2L and F1L genes of ORFV was established. A series of conditions and its performance were comprehensively evaluated. The optimized ELISA reaction conditions were: the optimal coating amount of antigen was 0.25 μg/mL, 5% skim milk powder was closed for 1 h, the optimal dilution of serum was 1:200, the optimal incubation time of the rabbit anti-goat IgG was 1:8000, the optimal color development time of TMB was 15 mins, and the threshold value of negative-positive was 0.358. The method specifically detects anti-ORFV antibodies and does not cross-react with positive sera for other common goat pathogenic bacteria antiserum. ORFV-positive sera were still positive after 1:512 dilution, with intra-batch coefficient of variation (CV) between 7.1% and 9.5% and inter-batch CV between 5.0% and 7.6%; 51% (92/180) of immunized goat serum samples were tested positive and 14.44% (14/63) of non-immunized goat serum samples were positive. The results show that the indirect ELISA antibody assay established in this study has good specificity, sensitivity and reproducibility, and provides a technical tool for clinical ORFV serum antibody detection and epidemiological investigation.

Finger nodules with a papulovesicular hands and feet eruption: a complicated human Orf virus infection

BACKGROUND

Orf virus (ORFV) is the pathogen responsible for Orf, a zoonotic viral infection that can be spread to humans from sheep and goats. Here, we present a case of human Orf complicated by an immune-related reaction, to raise awareness of this under-recognized disease avoiding unnecessary investigations and overtreatment.

CASE REPORT

A 51-year-old woman with no previous medical history presented with a one-week history of three asymptomatic swelling nodules with a grey necrotic center and red outer halo on her index finger. At physical examination there was also a pruritic papulovesicular eruption on her hands and feet. She reported a recent contact with a goat which had a similar nodular lesion in its mouth. A biopsy of the lesions was performed and a diagnosis of Orf complicated by widespread erythema multiforme was made based on the clinical and histopathological features. The lesions spontaneously resolved within the next 2 weeks.

CONCLUSIONS

Orf is not very prevalent in our region, so we performed a biopsy of the lesion to guide us toward a diagnosis. However, we should remember that the diagnosis of ecthyma relies on clinical evaluation and epidemiological criteria.

Orf Nodule with Erythema Multiforme during a Monkeypox Outbreak, France, 2022

A 26-year-old patient in France who worked as a butcher sought care initially for erythema multiforme. Clinical examination revealed a nodule with a crusty center, which upon investigation appeared to be an orf nodule. Diagnosis was confirmed by PCR. The patient was not isolated and had a favorable outcome after basic wound care.

Orf progressiva: giant progressive and destructive infections in the immunocompromised

Orf virus causes a self-limited infection in humans that resolves without scarring within 6-12 weeks. However, lesions in the immunocompromised can be progressive and disfiguring. The lesions frequently recur after treatment. To our knowledge, there are eleven published cases of these infections. We propose the name orf progressiva to call attention to this progressive, treatment-resistant entity. We present a 43-year-old male ranch owner with a history of renal transplantation who contracted an orf infection from his lamb. The infection recurred despite attempts at debridement, but achieved near complete resolution after treatment with imiquimod and valacyclovir. The histologic findings of orf progressiva are identical to the early stages of classic orf infection and are characterized by epithelial hyperplasia, intracytoplasmic eosinophilic inclusions, and an edematous, vascular dermis. There is no standard treatment for orf progressiva. Surgical excision has frequently resulted in rapid reoccurrence. Topical therapies such as imiquimod and cidofovir cream in combination with excision have been successful in some cases. Acyclovir or valacyclovir with imiquimod has been reported to be effective. Two patients achieved cure with imiquimod alone. We summarize these cases to prompt recognition of orf progressiva as a distinct clinical entity that requires treatment.

Feast of Sacrifice and Orf, Milan, Italy, 2015-2018

Orf (ecthyma contagiosum) is an infection of the skin caused by a DNA virus belonging to the genus Parapoxvirus. We recently observed 7 cases of orf in Muslim men living in the metropolitan area of Milan, Italy, who acquired the infection after the Feast of Sacrifice.

Human Infection with Orf Virus and Description of Its Whole Genome, France, 2017

Zoonotic transmission of parapoxvirus from animals to humans has been reported; clinical manifestations are skin lesions on the fingers and hands after contact with infected animals. We report a human infection clinically suspected as being ecthyma contagiosum. The patient, a 65-year-old woman, had 3 nodules on her hands. She reported contact with a sheep during the Aïd-el-Fitr festival in France during 2017. We isolated the parapoxvirus orf virus from these nodules by using a nonconventional cell and sequenced the orf genome. We identified a novel orf virus genome and compared it with genomes of other orf viruses. More research is needed on the genus Parapoxvirus to understand worldwide distribution of and infection by orf virus, especially transmission between goats and sheep.

Human Orf: An Under-recognized Entity

Dear Editor, Orf, also called contagious ecthyma, contagious pustular dermatitis, sore mouth, or scabby mouth, is a highly contagious zoonotic disease which is caused by a double-stranded DNA virus, ORFV (Parapoxvirus genus of the family Poxviridae) (1). The infection is endemic to sheep and goats, and humans are infected either through direct transmission from active lesions on infected animals or through contact with fomites (2). Orf is an occupational hazard and the population at risk includes shepherds, butchers, farmers, wool shearers, and veterinarians (2,3). Professionals rarely seek medical attention as they are aware of its benign nature (4). A 59-year-old woman presented with two painful plaques involving the dorsal aspect of her right thumb and the first interdigital space of the left hand. On examination, targetoid appearance with a central umbilication surrounded by a violaceous bullous halo was observed (Figure 1). The patient had been raising goats on her farm that recently presented udder and perioral crusted lesions. She did not wear gloves while performing this task. A skin biopsy was performed and showed elongation of the rete ridges, edematous papillary dermis, and eosinophilic intracytoplasmic inclusions in vacuolated cells (Figure 2). A diagnosis of human orf was established and the patient was started on a topical antiseptic solution to prevent secondary infection. The lesions healed without scarring after 6 weeks. Orf is characterized by one or multiple nodules on the hands and fingers, but also on the feet, legs, neck, and face. After an incubation period of 3-7 days, the lesions evolve through six clinical stages (2-4): (1) maculopapular stage (days 1-7), with erythematous macules or papules; (2) target stage (days 7-14), with necrotic center and red outer halo; (3) acute stage (days 14-21), in which the nodule begins to weep; (4) regenerative stage (days 21-28), in which the nodule becomes dry; (5) papilloma stage (days 28-35), where the lesion become papilloma-like and forms a dry crust; (6) regression stage (after 35 days). The lesions may be accompanied by lymphangitis, lymphadenopathy, malaise, fever, erysipelas, and occasionally erythema multiforme and bullous pemphigoid (3). Orf is usually a clinical diagnosis (2-4). The characteristic clinical appearance and location of the lesions along with the history of contact with infected animals is sufficient to establish a diagnosis. The differential diagnosis includes milker's nodule, cutaneous anthrax, neutrophilic dermatosis, atypical mycobacterial infection, cutaneous leishmaniasis, pyogenic granuloma, keratoacanthoma, and fungal infection (4,5). Further investigations are performed only when the diagnosis is in doubt and include electron microscopy, virology, enzyme-linked immunosorbent assay, or PCR-based approaches (4). The histological findings depend on the stage of the lesion and include eosinophilic inclusion bodies, epidermal necrosis, vacuolated keratinocytes, a dense mixed dermal infiltrate, and delicate finger-like projections in the epidermis (6).There is no specific treatment since the disease resolves spontaneously within 6-8 weeks, but successful application of cryotherapy, topical imiquimod, and cidofovir has been reported without supporting evidence (4). Surgical debridement should be avoided because it prolonged the recovery period (5). For prevention, wearing nonporous gloves, washing after handling, and isolation of infected animals is effective (2,4). In the present case, the diagnosis of orf was established in a straightforward manner after a good clinical examination and occupational history, allowing us to reassure the patient on its benign nature. The knowledge of this diagnosis prevents multiple complementary investigations (blood tests, histopathology, skin cultures, PCR detection, and electron microscopy) and unnecessary overtreatment. Although a rare entity, the predominant hand involvement in professionals can have significant morbidity that reflects on their productivity and quality of life. This reinforces the need for using appropriate measures to prevent animal-to-human transmission.

Orf Virus Infection in Humans: A Review With a Focus on Advances in Diagnosis and Treatment

Ecthyma contagiosum, also called contagious pustular dermatosis, is a zoonotic disease caused by the orf virus (OrfV). As a member of the poxviridae family and parapoxvirus genus, this dermatotropic virus has developed an array of mechanisms by which to evade the host immune system in both humans and animals. The ubiquitousness of this pathogen in sheep, goats, and deer has led to the development of orf in diverse areas around the world. Human disease occurs via direct contact with infected animals or fomites. Rarely, human-to-human transmission has been reported. The disease progresses through six clinically distinct dermatologic stages and lesions usually heal in three to six weeks without scarring. Farmers, veterinarians, and hunters represent high-risk groups, as their repeated contact with livestock and wild animals predisposes them to infection. With an increasing number of cattle, livestock, and wild animals being kept as pets, human orf may become more prevalent in the future. Taken with the lack of a widely accepted and successful antiviral treatment regimen, this demonstrates the importance of conducting additional research to further elucidate the pathogenic effects of the OrfV in humans. J Drugs Dermatol. 2017;16(7):684-689.

Human Orf (Ecthyma Contagiosum)

Orf is a viral cutaneous infection typically seen on the hands of people involved in sheep and goat farming. We report 31 cases of orf and consider its pathology, characteristic appearance, diagnosis, treatment and complications.

[Preparation,Identification,and Application of Monoclonal Antibody against Orf Virus 118 Protein]

This study was designed to prepare a monoclonal antibody against Orf virus 118 protein and explore the biological properties of ORFV118 using this antibody. We constructed a recombinant plasmid pET33b-ORFV118 that contained a full-length ORFV118 gene. The plasmid was transformed into E.coli BL21,and the expression of ORFV118 was induced by isopropyl-β-d-thiogalactoside (IPTG).Prokaryotic ORFV118 was purified via Ni-NTA affinity chromatography and was subsequently used as an antigen to immunize mice. An anti-ORFV118 antibody was prepared using hybridoma technology. The titer and specificity of this antibody were tested by an indirect ELISA and Western blot/immunohistochemistry, respectively. We successfully obtained three antibody-secreting hybridomas,1A2,3B5,and 5D10.The titers of the three hybridomas were 1:10000,1:6400,and 1:8000.The monoclonal antibody (mAb),1A2 and the highest titer was selected for further research. The mAb 1A2,an IgG1 type antibody was bonded to its immunizing antigen, both the eukaryotic and natural ORFV118 with high specificity. The immunohistochemical analysis showed that the focal specific staining was restricted to the epidermal layer and subcutaneous tissue, which conformed to the characteristics of an ORFV infection. The mAb 1A2 recognized ORFV118with high specificity. Further study of mAb 1A2 will facilitate our understanding of ORFV118 and provide potentially novel methods for the diagnosis, prevention, and treatment of Orf.

Orf with unusual features

We describe a case of Orf in an immunocompetent man with no history of direct contact with farm animals. The patient presented with numerous large lesions on hands and feet including a lesion in the subungual area. Later on multiple lesions with more bizarre morphology developed on the trunk. The diagnosis was suspected on clinical appearance of the lesion and confirmed later by histopathology. We consider contact with contaminated soil as the possible source of infection as virus can survive in pastures. Awareness of unusual clinical patterns of known entities is important to avoid unnecessary interventions.

Swan-Neck Deformity and Paresthesia Following Giant Orf

Orf is a zoonotic infection caused by a parapoxvirus that primarily infects sheep and goats. Human orf infection can take place when abraded skin comes into contact with infected animals. It occurs most commonly on the index finger. The characteristic lesion resembles a tumor and resolves spontaneously, usually without any complications. However, rare complications such as lymphangitis, adenitis, erythema multiforme, erysipelas, papulovesicular eruption, Pseudomonas aeruginosa infection, and bullous pemphigoid have been reported. Herein, we report a case of giant orf causing swan-neck deformity and paresthesia. These complications have not been previously reported in the literature.

ORF virus infection in a hunter in Western Austria, presumably transmitted by game

A variety of animals host parapoxviruses. Orf virus is prevalent in sheep and goats in the Tyrol region of Austria and Northern Italy. Zoonotic infections in humans mostly occur after occupational exposure. We report here a case of a hunter with a typical Orf lesion (contagious ecthyma) on the finger, with no history of direct contact with domestic animals. Three weeks previously he had been hunting chamois (Rupicapra rupicapra) and cut his finger while handling a carcass. Parapoxvirus infection was confirmed by electron microscopy and PCR, and the species was identified by DNA sequencing. The sequence was highly homologous with prevalent sheep Orf virus and rather distant from parapoxviruses found in red deer in Northern Italy. As this case indicated that the infection was acquired via game, we performed spot testing in the suspected area and detected several seropositive animals. This is a strong indication that Orf virus has been introduced into chamois in Western Austria. This probably occurred via roaming domestic sheep sharing the high alpine areas during the summer months.

[A 61-year-old woman with an infected little finger]

A 61-year-old woman was seen at the Emergency Department with a progressive infection of the little finger. A solid hemorrhagic bulla was seen with 2 central ulcers and the diagnosis 'ecthyma contagiosum' was made. This is a self-limiting infection caused by a parapoxvirus in sheep and can be transmitted to humans through direct contact with infected animals.

A case of orf (ecthyma contagiosum) with multiple lesions

Orf, also known as ecthyma contagiosum or contagious pustular dermatitis, is a viral zoonotic disease resulting from the direct or indirect contact of damaged skin with infected animals. The causative microorganism is the orf virus, an epitheliotropic DNA virus from the Parapoxvirus group, which generally infects sheep, goats, and various other domestic and wild ovine animals. A male patient presented to our outpatient clinic with multiple nodular lesions on his right wrist after incurring an injury during ovine slaughter. Diagnoses other than ecthyma contagiosum were eliminated by punch biopsy. Orf generally manifests as solitary lesions on hands and fingers, but it may rarely present as multiple nodular lesions. Here we present the case of a 42-year-old man diagnosed with orf based on clinical and histopathological findings.

Multiple finger nodules and an erythematous rash - a case study

A previously well male, 18 years of age, from a rural community, presented with three painful, itchy nodules on the fingers of his left hand, which had been present for 1 week. He had been prescribed amoxicillin clavulanate but presented again when there was no improvement after 4 days of taking antibiotics. Examination revealed three erythematous and umbilicated nodules without any halo, but with a central depression with exudate (Figure 1a). No specific treatment was instituted at this visit. One week later the patient re-presented with new erythematous lesions on the palms and dorsum of his hands. The original three lesions had improved and were drier than previously (Figure 1b, c). The new lesions disappeared after 2 weeks and the original lesions after 4 weeks, without any other treatment.

Centers for Disease Control and Prevention (CDC). Human Orf virus infection from household exposures - United States, 2009-2011

Orf, also known as contagious ecthyma, is a zoonotic infection caused by a dermatotropic parapoxvirus that commonly infects sheep and goats; it is transmitted to humans through contact with an infected animal or fomites. In humans, orf manifests as an ulcerative skin lesion sometimes resembling bacterial infection or neoplasm. Human infection typically is associated with occupational animal contact and has been reported in children after visiting petting zoos and livestock fairs. Cases lacking these exposure histories might be misdiagnosed, leading to unnecessary treatment of orf lesions, which do not usually require any specific treatment. This report describes four cases of human orf associated with household meat processing or animal slaughter, highlighting the importance of nontraditional risk factors. Orf should be included in the differential diagnosis of patients with clinically compatible skin lesions and a history of household meat processing or animal slaughter. Persons and communities with these exposure risks also should receive counseling regarding the use of nonpermeable gloves and hand hygiene to prevent infection.

Investigation and analysis of a human orf outbreak among people living on the same farm

Human orf is a viral zoonotic infection caused by Parapoxvirus. The skin lesions of human orf can be misdiagnosed as cutaneous anthrax leading to overtreatment and also fear. This study was conducted to analyze an outbreak which led to deaths among kids and lambs in the same flock, and skin lesions in some persons who were living on the same farm that were initially diagnosed as cutaneous anthrax by a practitioner. Eight patients with skin lesions and eleven persons who had no skin lesion were considered as patients and control groups, respectively. The cultures obtained from the lesions of all patients were negative for Bacillus anthracis. The diagnosis of skin lesions was done by clinical findings, histopathological examination and PCR as human orf. To be under 20 years of age, direct contact with the animals, and contact with flayed skin of sick animals were the risk factors for human orf (Odds Ratio 7.5; 95% Confidence Interval 1.02-54.54, OR 12.25; 95% CI:1.3-100.9, OR 16.67; 95% CI:1.65-148.20, respectively). Orf should be kept in mind in the differential diagnosis of skin lesions resembling anthrax. For control and prevention of orf, transmission routes should be known; good hand hygiene and other personal protective measures have to be implemented.

[A woman with skin lesions on her hand]

A Moroccan woman was seen with a blister on her left thumb and a rash on the palm of the left hand. She did not recall burning herself, but prepared sheep meat regularly. It appeared the skin lesions were caused by orf (ecthyma contagiosum).

[The "Orf" virus: focus and review of the literature]

Orf is an infection often unknown to practicians throughout the world. The first known cases were registered at the end of the 19th century. The virus affects ovines and caprins and is characterized by cutaneous and/or mucosae lesions. It is strongly resistant and the survival time is important in the outside environment. The morbidity of Orf is far higher than its mortality. The virus is transmitted by direct and indirect contact among humans, who became vectors themselves. Those subjects that are in contact with the animals in question due to professional reasons are at risk in particular. The same goes for attendants and participants of religious feasts. The preferred localization of lesions in humans is the hands. The diagnostic is easily set by the anamnesis and the clinical characteristics of the lesions except when it happens to be a particular form. The complications are nearly exclusively related to the unawareness of the virus in form of inappropriate medical acts. The evolution is spontaneous and the unique treatment is the prophylaxis of bacterial infection as well as a constant surveillance.

Orf: contagious pustular dermatitis

Orf is a common viral infection in sheep. It spreads to humans by direct contact. It is self-limiting, treatment having no beneficial effect. Misdiagnosis by those unfamiliar with its characteristic features is common, and may result in unnecessary treatment with antibiotics or surgery. We present a series of five cases of Orf in children of farmers in the west of Ireland, seen over a 10 year period.

[Orf of the hand]

INTRODUCTION

The orf is a zoonotic infection which can be transmitted to humans.

OBJECTIVE

The aim of our report is to describe this often misdiagnosed viral infection in a man with an orf of the hand appearing after the feast of the sacrifice.

CASE REPORT

A 40-year-old man with no past medical history, presented with a nodular lesion on the fifth right finger evolving for 3 weeks which had appeared 2 weeks after the feast of the sacrifice. Histology showed a vacuolar degeneration of keratinocytes probably of viral origin. Both histological aspect and the contact with sheep, led to the diagnosis of hand orf. Three weeks later the lesion had spontaneously resolved.

CONCLUSION

Orf is an infectious mucocutaneous disease due to a parapoxvirus. It is more frequent in professionally exposed persons (veterinary, butchers...). But, in our country, the frequency of the orf increases after the feast of the sacrifice and remains undiagnosed because patients do not consult. The diagnosis may be confirmed by electron microscopy, conventional histopathology or by isolation of the virus by PCR. Information on the benign character of the disease and reassurance of the infected patient are very important because lesion usually resolves spontaneously.

ORF virus infection in children: clinical characteristics, transmission, diagnostic methods, and future therapeutics

Orf virus leads to self-limited, subacute cutaneous infections in children who have occupational or recreational contact with infected small ruminants. Breaches in the integument and contact with animals recently vaccinated for orf may be important risk factors in transmission. Common childhood behaviors are likely important factors in the provocation of significant contact (ie, bites) or in unusual lesion location (eg, facial lesions). Clinician recognition is important in distinguishing orf infection from life-threatening cutaneous zoonoses. Recently developed molecular techniques provide diagnostic precision and newer topical therapeutics may hasten healing.

Phylogenetic correlation of Greek and Italian orf virus isolates based on VIR gene

Thirteen orf virus isolates obtained during the time period between 1995 and 2004 from crusted scab lesions of nine sheep and four goats from different geographical areas of Greece and Italy with suspected contagious ecthyma infection were analyzed. DNA of all isolates was successfully amplified by PCR with the primers 045F-045R and identified them as parapox virus. Partial DNA sequence of orf virus interferon resistant (VIR) gene, phylogenetic analysis of the available isolates and amino acid comparison of the interferon resistance protein encoded by this genomic region was carried out. According to the results of the present report a precise characterisation of the genomic region studied might provide evidence for the genetic variation and movement of the circulating orf virus strains.

Centers for Disease Control and Prevention (CDC). Orf virus infection in humans--New York, Illinois, California, and Tennessee, 2004-2005

Orf virus is a zoonotic parapoxvirus endemic to most countries in the world and is principally associated with small ruminants (e.g., sheep and goats). Human orf infections appear as ulcerative skin lesions after contact with an infected animal or contaminated fomite. This report summarizes the epidemiologic and laboratory investigations of four sporadic cases of human orf infection, emphasizing the temporal association between human lesions and skin trauma or recent flock vaccination with live orf vaccine. This zoonotic infection shares clinical manifestations and exposure risks with other, potentially life-threatening zoonoses (e.g., cutaneous anthrax) and is likely under-recognized because of a lack of clinical suspicion and widely available diagnostics. Barrier precautions and proper hand hygiene are recommended for the prevention of orf virus infection in humans.

Laboratory diagnosis of contagious ecthyma: comparison of different PCR protocols with virus isolation in cell culture

A new polymerase chain reaction (PCR) assay for rapid diagnosis of contagious ecthyma was designed and applied to 21 clinical samples from Greece. This assay, which detects a highly conserved gene from the parapox genome, was evaluated for its sensitivity and specificity in order to be considered as a useful diagnostic tool. A comparative study with two published PCR protocols one using primers PPP1-PPP3, PPP1-PPP4 which targets putative virion envelope gene B2L and the other using VIR1-VIR2 primers which amplifies ORF virus interferon resistant (VIR) gene, as well as cell culture virus neutralization assay was carried out. All samples tested were amplified successfully with the PCR protocol established in the laboratory. The combination of primers PPP1-PPP3 and PPP1-PPP4 in a semi-nested PCR gave a positive result in 20 of 21 samples while primers VIR1-VIR2 failed to amplify successfully 7 of 21 samples. The diagnostic value of parapox viral DNA amplification was also compared with the results of virus isolation by cell culture and was positive in three samples that the virus isolation was obtained.

Diagnosis of orf virus infection in humans by the polymerase chain reaction

The orf virus is the causal agent of contagious ecthyma in goats and sheep. The infection can be transmitted to humans and represents a typical example of occupational zoonosis. In Italy, the incidence of human infection remains uncertain because the disease is rarely reported or diagnosed. In this paper, we report a case of human orf virus infection and the laboratory methods of diagnosis. We demonstrated a genomic identity between the conserved and the variable regions of the genome of the viral strains isolated from the human patient and from the infected sheep confirming that there is no specific clone infecting humans rather than animals.

[Three patients with orf (ecthyma contagiosum)]

Orf was diagnosed in three patients: a 16-year-old Moroccan girl who had cut her finger in a butcher's shop, a 47-year-old Dutch woman who had allowed a lamb to suck on her finger on a children's farm, and a 50-year-old Dutch farm woman. Orf or ecthyma contagiosum is a well-known viral disease among sheep and goats. Transmission to humans as a zoonosis is rare but can take place via direct contact with infected animals or animal products. The clinical picture is usually characterized by a solitary lesion that develops on the dorsal side of the fingers or hands. This viral condition produces little or no systemic complaints and the lesions usually regress spontaneously without scar formation within 6 weeks (range 4-9 weeks). The correct diagnosis can usually be made on clinical grounds. The diagnosis may be confirmed by demonstration of the virus by electron microscopy or the polymerase chain reaction in fluid obtained from the skin lesions or by conventional histopathology. Early clinical recognition and knowledge of this benign, self-limiting viral condition is vital to avoid unnecessary surgical intervention. Proper information and reassurance of the infected patient are very important. All three patients recovered.

[Ecthyma contagiosum (Orf) as an uncommon differential diagnosis of infections of the hand]

Orf of the hand is considered as an uncommon viral infection which is usually acquired through contact with infected sheep and goats. Indirect infections through contaminated knives or meat have been reported. Many authors feel that the disorder is more common than reported because the disease is often misdiagnosed and the course is usually self-limiting with spontaneous healing within several weeks. Diagnosis is mainly made by patient's history and clinical course. It is important to know the benign nature of human orf, since complications seem to be caused by overtreatment.

A severe case of contagious ecthyma in Tswana goats

The first severe case of caprine contagious ecthyma (parapox) in Tswana goats is described from Botswana. Affected animals were indigenous adult Tswana goats. The case involved a flock of 12 goats of which 4 (33.3%) were very severely affected but none died. The lesions were confined to the head and included swollen lips, swollen submandibular lymph nodes, gingivitis, glossitis, ulceration on lip and gum mucosae and scab formation on ulcerated areas. No lesions were found on other parts of the body. This case was clinically indistinguishable from bluetongue.