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An outbreak of lumpy skin disease (LSD) occurred among cattle and water buffaloes in Egypt in 2006. Polymerase chain reaction (PCR) and the agar gel precipitation test (AGPT) were compared. Eight of ten (80%) tissue specimens from diseased cattle were positive with AGPT while 100% were positive with PCR. Of ten tissue specimens from diseased water buffaloes, 70% were positive with AGPT while 100% were positive with PCR. Ten milk samples were obtained from diseased water buffaloes; PCR detected nucleic acid of LSD virus (LSDV) in 50% while AGPT failed to detect LSDV antigen. Water buffaloes are susceptible to LSDV infection. The clinical signs of LSD were less severe in water buffaloes, but the virus was excreted in their milk. Diagnosis of LSD outbreaks by PCR will facilitate rapid application of control measures. Mass vaccination should be applied in both cattle and water buffaloes in Egypt using an effective specific vaccine against LSD, such as the attenuated Neethling strain vaccine or a recombinant vaccine.

An outbreak of peste des petits ruminants (PPR) was recorded in Kalubia province, Egypt in 2006, affecting a large population of migratory goats and sheep over a huge geographical area. Epidemiological, clinical and laboratory investigations were performed. Diseased animals showed pyrexia, erosive stomatitis, enteritis and bronchopneumonia. Clinical manifestations were more severe in goats. The overall morbidity, cumulative mortality and case fatality rates were 26.1%, 10.5% and 40.2%, respectively, and were significantly higher in young animals. Post-mortem examination showed emaciation, congested mucous membranes, lymphadenopathy, hepatosplenomegaly, haemorrhagic necrosis of the abomasal and intestinal mucosa, pleurisy and lung consolidation. Forty oculonasal swabs and 243 serum samples from diseased animals were tested for PPR antigen and antibodies using immunocapture and competitive enzyme-linked immunosorbent assays (ELISA), respectively. PPR antigen was detected in 30/40 (75%) of the swabs. PPR virus was identified in inoculated Vero cells using immunocapture ELISA and fluorescent antibody technique (FAT); 33/40 (82.5%) and 36/40 (90%) samples were positive, respectively. Of 243 sera, 154 (63.4%) contained PPR antibodies. Circulation of PPR among the migratory sheep and goat flocks was demonstrated. Strict serosurveillance and monitoring of PPR with vaccination of migratory flocks at borders is required for effective control of the disease.

This study describes an epizootic of respiratory tract disease caused by influenza virus infection in a large population of equines in Luxor and Aswan, Upper Egypt, during the winter of 2000. The epizootic started in January and the infection rate reached its peak in February before gradually decreasing until the end of April, 2000. Horses, donkeys and mules of all ages and both sexes were affected. Free movement of the infected equines and direct contact between the animals at markets facilitated the rapid spread of the disease. The cause of the epizootic was established by use of serological testing and the identification of the influenza virus in nasal secretions. Egg inoculation and the haemagglutination test were used to detect the influenza virus. Both haemagglutination inhibition (HI) and agar gel precipitation tests were performed to identify the isolated influenza virus using reference antisera against A/Equi-1 (H7N7) and A/Equi-2 (H3N8). Antibodies against the equine influenza virus were demonstrated in 416 (95.6%) out of 435 collected sera using the HI test. High rectal temperature, inappetence, conjunctivitis, redness of nasal mucosa, a serous to mucopurulent nasal discharge and a harsh dry cough were the most common clinical manifestations. Stress factors, such as using equines for heavy transportation and drawing, precipitated the onset of the disease, intensified the clinical syndrome, delayed recovery and facilitated secondary bacterial infection. The present study suggested that the absence of a vaccination programme against equine influenza was one of the principal causes of the spread of infection during this outbreak. In conclusion, the implementation of a national equine influenza vaccination programme, using an effective updated vaccine, is essential in Egypt.

This study reported field outbreaks of bovine viral diarrhoea virus (BVDV) infection, either alone or mixed with bovine herpesvirus-1 (BHV-1) and/or parainfluenza-3 virus (PI-3V) in Egypt during 2000. In Lower Egypt, young calves in three cattle herds in El-Minufiya Province, El-Fayoum Province and in governmental quarantine in El-Behira Province, showed symptoms of enteritis, either alone or accompanied by respiratory manifestations. The affected herds were visited and the diseased animals were clinically examined. Many epidemiological aspects, such as morbidities, mortalities and case fatalities, as well as the abortive rate, were calculated. Ethylenediamine tetra-acetic acid-blood samples, sterile nasal swabs and serum samples were obtained for virological and serological diagnosis. The laboratory investigations revealed that the main cause of calf mortalities in the three herds was infection with BVDV, either alone, as on the El-Minufiya farm, or mixed with PI-3V, as on the El-Fayoum farm, or mixed with both BHV-1 and PI-3V, as in the herd in governmental quarantine in El-Behira Province. A total of nine dead calves from the three herds were submitted for thorough post-mortem examination. Tissue samples from recently dead calves were obtained for immunohistochemical and histopathological studies. The most prominent histopathological findings were massive degeneration, necrosis and erosions of the lining epithelium of the alimentary tract. Most of the lymphoreticular organs were depleted of lymphocytes. In pneumonic cases, bronchopneumonia and atypical interstitial pneumonia were evident. The present study suggested that the immunosuppressive effect of BVDV had predisposed the animals to secondary infection with BHV-1 and PI-3V. This study concluded that concurrent infection with BVDV, BHV-1 and PI-3V should be considered as one of the infectious causes of pneumoenteritis and, subsequently, the high morbidities and mortalities among young calves in Egypt. Preventive and control measures against these infectious agents should therefore be adopted. All animals imported into Egypt should be free from BVDV infection. Control programmes for the detection and removal of BVDV-persistent cattle should be applied in cattle herds all over the country.

In 1989, 220 Holstein Friesian cattle (212 heifers and eight bulls) were imported from Minnesota, USA, to form a closed dairy herd in Arab El-Aoumar, Assiut, Upper Egypt. In November 1996, some abnormal signs such as loss of weight, decreased milk yield, external lymphadenopathy and decreased appetite were observed on this farm. Serological screening by enzyme-linked immunosorbent assay revealed a seroprevalence of antibodies directed against bovine leukaemia virus (BLV) of 37.7% in cattle under 2 years old and of 72.8% in animals more than 2 years old. Diagnosis was confirmed by the detection of BLV proviral DNA using polymerase chain reaction with primers amplifying a fragment of the env gene. Out of 21 tested leucocyte fractions from individual animals, 15 were positive showing a BLV-specific amplicon of 444 base pairs. Analysis of the amplicons for restriction fragment length polymorphisms and DNA sequencing results allowed the isolates to be typed. Since this was the first recorded case of enzootic bovine leukosis in Upper Egypt, strict quarantine measures were adopted and all serologically positive animals in the herd were culled.

An epizootic of Rift Valley fever (RVF) occurred in Egypt between April and August 1997. The signs among infected cattle and sheep were high fever, icterus, bloody diarrhoea and abortion. Aborted sheep foetuses and sera from the affected herds were collected in the Aswan and Assiut Provinces, Upper Egypt, for virological and serological examination. A cytopathic effect was detected in Vero cell cultures 48 h after inoculation with the foetal liver and spleen suspensions. The same suspensions caused paralysis and mortalities two to three days post intracerebral injection in mice. The isolated virus was identified using an agar gel precipitation test (AGPT) and a direct fluorescent antibody technique. Serological examination revealed that all tested sheep (57) and cattle (93) gave positive results to serological tests, using a complement fixation (CF), serum neutralisation (SN) and indirect immunofluorescence assay; while only 48 (84.2%) out of 57 sheep sera and 69 (74.2%) out of 93 cattle sera gave positive results using an AGPT. Titration of the serum samples indicated that SN is more sensitive than CF. Importation of infected ruminants, especially camels from the Sudan, is the principal source of infection. Aswan, the nearest Egyptian province to the Sudan, is the focus of RVF virus infection in Egypt. As a result of high insect populations, the epizootics of RVF have usually occurred during the summer in Egypt. Reoccurrence of epizootics from time to time indicates failure of the applied RVF vaccination programme in Egypt.