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This work aimed to study the clinical aspects and immune response of pregnant and non-pregnant ewes vaccinated with attenuated MP12 RVF vaccine. Non-pregnant ewes showed slight elevation of body temperature lasted for one day post-vaccination. There were no detectable clinical signs of RVF disease. Pregnant ewes showed no elevation in body temperature, no abortion and delivered healthy lambs (without abnormalities). RVF virus was detected on the 2nd day post-vaccination in 15 out of 18 serum samples using RT- PCR. IgM antibodies were detected on 7 days post-vaccination (DPV) and persisted up to 150 DPV with a titer ranged from 100 – 800. IgG antibodies were detected on 7 DPV reaching the peak on 60 DPV and persisted up to 360 DPV with a titer ranged from 100 – 800. Maternal immunity appeared in newly born lambs after ingestion of colosrum and lasted up to 4 months. It is concluded that MP12 RVF vaccine is safe and potent for vaccination of sheep.

In June, 2003, Egypt's hospital-based electronic disease surveillance system began to record increased cases of acute febrile illness from governorates in the Nile Delta. In response to a request for assistance from the Egyptian Ministry of Health and the World Health Organization (WHO), the U.S. Naval Medical Research Unit No. 3 (NAMRU-3) provided assistance in identifying the cause and extent of this outbreak. Testing of human clinical samples (n=375) from nine governorates in Egypt identified 29 cases of RVF viremia that spanned the period of June to October, and a particular focus of disease in Kafr el Sheikh governorate (7.7% RVF infection rate). Veterinary samples (n=101) collected during this time in Kafr el Sheikh and screened by immunoassay for RVFV-specific IgM identified probable recent infections in cattle (10.4%) and sheep (5%). Entomologic investigations that focused in rural, rice growing villages in the Sidi Salim District of Kafr el Sheikh during August-September, 2003, collected, identified, and tested host-seeking female mosquitoes for the presence of pathogenic viruses. Three isolates of RVF virus (RVFV) were obtained from 297 tested pools of female mosquitoes and all three RVFV isolates came from Cx. antennatus (Becker). While Cx. pipiens has been considered the primary vector of RVF virus in Egypt and is often the most common man-biting species found, Cx. antennatus was the dominant species captured at the 2003 outbreak location in Kafr el Sheikh governorate. This is the first time that Cx. antennatus has been found naturally infected with RVFV in Egypt.

Summary: We conducted a prospective cohort study to determine prevalence and incidence of West Nile virus (WNV) in Egypt. Cohorts were established in Upper (UE), Middle (ME), and Lower (LE) Egypt. Additionally, a cross-sectional serosurvey was performed in the North (NS) and South (SS) Sinai. Cohorts were bled initially and 1 year later. Sera were tested for WNV-IgG by ELISA and positive sera were confirmed by plaque reduction neutralization test (PRNT). Sentinel chicken flocks placed in the above sites were bled monthly for virus isolation and serology. Mosquitoes were collected monthly from the above sites and tested for WNV. Human seroprevalence rates were 35%, 27%, 14%, 1% and 7% in UE, ME, LE, NS and SS, respectively. Seroconversion rates were 18%, 17% and 7% in UE, ME and LE, respectively; 49% of the seroconverters reported undiagnosed febrile illness. Sentinel chickens showed seroconversion in all study sites. WNV was isolated from both sentinel chickens and mosquitoes in cohort sites. This study demonstrates that WNV was actively circulating during the study period in different areas in Egypt and causing febrile illness in a considerable proportion of individuals in the study sites. Keyword: West Nile virus in Egypt

An immunoperoxidase monolayer assay (IPMA) was adapted for the detection of antibodies to six arboviruses: three viruses within the flavivirus group (dengue 2, West Nile (WN) and yellow fever) and three in the phlebovirus group (Rift Valley fever (RVF), sandfly fever Naples and sandfly fever Sicilian). Antibody titers of homologous hyper-immune mouse ascitic fluid (HMAF) measured by IPMA were two to eight-fold less than those determined by ELISA. In tests with heterologous HMAF, cross-reactions frequently observed in ELISA, particularly in the flavivirus group, were absent in all IPMA titrations. With human serum samples tested for antibodies to RVF (n = 52) and WN (n = 90), the sensitivity of IPMA as compared with ELISA was 96 and 91%, respectively, specificity of IPMA was 100%. In addition, the IPMA format has several advantages that make it a useful alternative to ELISA for diagnosing arboviral infections under field conditions.

Meningitis occurs throughout Egypt and is largely attributed to bacterial pathogens, but there is little information on fungal etiologies of meningitis. We, therefore, investigated fungal infections among Egyptian patients with acute and subacute meningitis who tested negative for bacterial and viral agents. A total of 1000 cerebrospinal fluid (CSF) samples collected from nine governorates of Egypt during 1998-2002 were initially stained with Gram's, India ink, and lacto-phenol cotton-blue stains, and examined under light microscope to detect fungal elements. All CSF samples were cultured on brain heart infusion, Wickerham and Staib agar media for fungus isolation. CSF with suspected Cryptococcus neoformans infections were also tested by latex agglutination test for antigen detection. Species identification of selected isolates was carried out at the Mycotic Diseases Branch, CDC, Atlanta, Georgia, USA. Fungal agents were detected microscopically and by culture in 17 of 1000 (1.7%) CSF samples tested. Ten of 17 were identified as C. neoformans var grubii (serotype A), 4 as Candida albicans, and one each of Aspergillus candidus, Rhodotorula mucilaginosa (rubra) and Nocardia spp (actinomycetes). Out of the 17 cases with fungal CSF infection, 8 died (Cryptococcus-3, Candida-2, Aspergillus, Rhodotorula and Nocardia) and 2 suffered neurological sequelae. Of the 10 cryptococcal meningitis patients, 4 were HIV positive and one was diagnosed with lymphoma. To our knowledge, this is the first study on isolation of fungi other than Cryptococcus from CSF of Egyptian patients with acute/subacute meningitis. Consideration must now be given to cryptococcosis and candidiasis as potential etiologies of meningitis in Egypt.

SummaryObjectivesThis study was conducted to identify the potential risk factors for human brucellosis infection in Samarqand, Uzbekistan.MethodsClinically identified cases admitted to different hospitals during 2004–2006 (N=144), and age-, sex- and residence-matched control patients (N=288) with other unrelated conditions, were included in this study. Structured questionnaires were completed and consent forms signed. Patients and controls were tested on site for Brucella infection by standard tube agglutination test and culture. Statistical analyses were performed with Stata software for univariate and multivariate analysis.ResultsAmong the 144 patients with confirmed brucellosis, 137 (95.1%) owned farm animals, 135 (93.8%) were from rural areas, and 119 (82.6%) were enrolled during the animal breeding season. Multivariate analysis indicated that brucellosis was highly associated with contact with aborted animals (adjusted matched odds ratio (AMOR) 87.19, 95% confidence interval (CI) 9.36–911.85; p

Three hundred eighteen European cows and 115 buffaloes were vaccinated with locally prepared Smithburn vaccine, of which, 100 cows and 20 buffaloes were pregnant. Twenty-eight cows aborted within 72 days post-vaccination, buffaloes did not abort. Blood samples collected 77 days post-vaccination from aborted cows, 17 pregnant cows, 5 pregnant buffaloes, and 32 non-pregnant cows. Sera were tested by ELISA for anti-RVF IgM and IgG. All aborted cows were strongly positive for IgG. Five of 17 cows and two of five buffaloes that did not abort were IgG positive. The percentage of IgM positives in aborted cows was 25% and 0% in non-aborted cows. The percentage of IgG positives in pregnant non-aborted cows was lower than in non-pregnant cows. The percentage of IgG positives of non-pregnant cows was lower than pregnant aborted cows. Virus was isolated from one aborted fetus. The nucleotide sequence of fetus virus was compared to Smithburn of Onderstepoort, local Smithburn and virus isolates from 1993 to 1994 and 1977 RVF outbreaks. The nucleotide sequences of Onderstepoort and Egyptian Smithburn vaccines were almost identical. The sequences of 1993-1994 isolates were identical to 1977 outbreak virus. Virus from the fetus had two mutations; it is apparently a variant that is genetically distant from local Smithburn and Onderstepoort vaccines. Fetus virus was genetically distant from virus of 1993/1994 and 1977 outbreaks. In conclusion, antibody response to vaccination with local Smithburn had occurred in some, but not all the cows and buffaloes. Virus isolation from the fetus suggests in utero transmission of used vaccine virus, which resulted in high abortions in European cows.

Surveillance for influenza A viruses in wild birds has increased substantially as part of efforts to control the global movement of highly pathogenic avian influenza A (H5N1) virus. Studies conducted in Egypt from 2003 to 2007 to monitor birds for H5N1 identified multiple subtypes of low pathogenicity avian influenza A viruses isolated primarily from migratory waterfowl collected in the Nile Delta. Phylogenetic analysis of 28 viral genomes was performed to estimate their nearest ancestors and identify possible reassortants. Migratory flyway patterns were included in the analysis to assess gene flow between overlapping flyways. Overall, the viruses were most closely related to Eurasian, African and/or Central Asian lineage low pathogenicity viruses and belonged to 15 different subtypes. A subset of the internal genes seemed to originate from specific flyways (Black Sea-Mediterranean, East African-West Asian). The remaining genes were derived from a mixture of viruses broadly distributed across as many as 4 different flyways suggesting the importance of the Nile Delta for virus dispersal. Molecular clock date estimates suggested that the time to the nearest common ancestor of all viruses analyzed ranged from 5 to 10 years, indicating frequent genetic exchange with viruses sampled elsewhere. The intersection of multiple migratory bird flyways and the resulting diversity of influenza virus gene lineages in the Nile Delta create conditions favoring reassortment, as evident from the gene constellations identified by this study. In conclusion, we present for the first time a comprehensive phylogenetic analysis of full genome sequences from low pathogenic avian influenza viruses circulating in Egypt, underscoring the significance of the region for viral reassortment and the potential emergence of novel avian influenza A viruses, as well as representing a highly diverse influenza A virus gene pool that merits continued monitoring.

From October 1991 to February 1992, an outbreak of acute fever (in which thick blood films were negative for malaria) spread rapidly in the city of Djibouti, Djibouti Republic, affecting all age groups and both nationals and foreigners. The estimated number of cases was 12,000. The clinical features were consistent with a non-haemorrhagic dengue-like illness. Serum samples from 91 patients were analysed serologically for flavivirus infection (dengue 1-4, West Nile, yellow fever, Zika, Banzi, and Uganda-S), and virus isolation was attempted. Twelve strains of dengue 2 virus were isolated. Dengue infection was confirmed by a 4-fold or greater rise in immunoglobulin (Ig) G antibody in paired serum specimens, the presence of IgM antibody, or isolation of the virus. Overall, 46 of the suspected cases (51%) were confirmed virologically or had serological evidence of a recent flavivirus infection. Statistical analysis showed that the presence of a rash was the best predictor of flavivirus seropositivity. In November 1992, Aedes aegypti was widespread and abundant in several districts of Djibouti city. A serological study of serum samples collected from Djiboutian military personnel 5 months before the epidemic showed that only 15/177 (8.5%) had flavivirus antibodies. These findings, together with a negative serosurvey for dengue serotypes 1-4 and yellow fever virus performed in 1987, support the conclusion that dengue 2 virus has only recently been introduced to Djibouti.

A competitive enzyme immunoassay (CEIA) was established and compared with other serological techniques for detecting Coxiella burnetii antibody in camels, goats, and sheep. This technique was evaluated because a conjugated anti-camel immunoglobulin was not available to serve as a direct signal for the demonstration of antigen-antibody reaction. A C. burnetii antibody-positive human serum and a peroxidase-conjugated anti-human immunoglobulin G were used as an indicator system competing against antibody in animal serum or as an indicator of the absence of antibody. Sera were considered antibody positive when the A414 of the test sera plus the competing positive antibody was less than or equal to 50% of the A414 of the negative-control serum plus the competing antibody. Antibody to C. burnetii was repeatedly demonstrated in 66% of camel serum samples (n = 200) by the CEIA. Among 48 camel serum samples, 71% were positive for antibody by CEIA versus 65% by EIA using peroxidase-labeled protein A. The CEIA detected C. burnetii antibody in 63% of sheep serum samples (n = 40) and in 50% of goat serum samples (n = 96), while the indirect fluorescent-antibody technique detected antibody in 38% of sheep and 34% of goat serum samples and the EIA detected antibody in 50% of sheep and 35% of goat serum samples. These data indicate that the CEIA is a reliable and sensitive technique for demonstrating C. burnetii antibody in camels, sheep, and goats.

Summary: Dengue fever (DF)/dengue hemorrhagic fever (DHF) has emerged as a global public health problem with countries in Asia and the Pacific sharing more than 70% of the disease burden. In 2004–2005 a total of 312 cases admitted to Pediatric and Sea Port Hospitals in Port Sudan were clinically diagnosed as DHF. The mortality rate recorded was 3.8% (n = 12). Of the cases 73.4% were patients 5–15 years of age. A total of 91.2% of cases were admitted during May and June 2005 with 49.4% residing in the eastern region of Port Sudan. Dengue shock syndrome was observed in 37 of 312 (11.9%). All patients had thrombocytopenia with platelets count ranged from

Epidemics of a malaria-like illness affected several thousand residents of the Dam Camp, a refugee camp near Hargeysa in Somalia, during 1985, 1986, and 1987. The disease was characterized by fever, chills, sweats, headache, back and joint pains for as long as 10 days in some patients. Blood smears from acutely ill patients were negative for malaria. Of 28 acute and 10 convalescent sera tested by the indirect fluorescent antibody (IFA) and by the hemagglutination inhibition (HI) tests, all were negative for antibody to Rift Valley fever, Crimean-Congo hemorrhagic fever, Sindbis, Chikungunya, yellow fever, and Zika viruses. However, antibody reactive to dengue 2 virus was detected by the IFA test in 39% (15/38), and 11 of 29 (38%) of the same sera were antibody positive by the HI test. Also, IgG antibody reactive to dengue 2 was demonstrated in 60% (17/28) of the same sera by the enzyme immunoassay (EIA), and 14% (4/28) were positive for IgM antibody. Of ten patients for which acute and convalescent sera were available, two developed four fold or greater rises in antibody titer evidencing infection. These data suggested that dengue virus may have been the cause of the epidemic among the Dam Camp refugees.

Nineteen street rabies virus strains, isolated in Egypt from humans (two), dogs (nine), cats (two), farm animals (two), gerbils (three), and a jackal were antigenically analyzed. The Pasteur strain used for the preparation of human rabies vaccine, the Flury high and low egg passage stains (HEP, LEP) used for animal vaccines, and the challenge virus standard (CVS) strain were also assayed. All were examined by the indirect fluorescent antibody test, using a panel of 20 monoclonal antibodies against the nucleocapsid of rabies and rabies-related viruses. The rabies isolates demonstrated patterns of reactivity with the antinucleocapsid panel different from those of the Pasteur, HEP, and CVS strains. Representative human, dog, and rodent isolates were analyzed by neutralization tests in mice, with a second panel of 19 monoclonal antibodies against rabies and Mokola envelope glycoproteins. With this panel, the isolates demonstrated patterns of reactivity different from the vaccine strains. These data indicate antigenic variation between wild virus and vaccine strains.