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OBJECTIVES: The present study was designed as a large-scale cross-sectional study to cast some light on the magnitude of hepatitis B virus (HBV) infection in Aseer Region, south-western Saudi Arabia, a region reported to be of the highest endemicity. METHODS: During the WHO hepatitis day of 2013, an aggressive health education campaign was launched in all the hospitals and primary health care centres in Aseer Region. Posters were distributed to encourage the local population to visit the health facilities to be tested for HBV. They were interviewed using a structured questionnaire. Detection of hepatitis B surface antigen (HBsAg) was done using a fourth-generation ELISA kits. RESULTS: The present study included 10,234 persons. The study revealed an overall seroprevalence of 5.9% (95% confidence interval [CI] = 5.5-6.4%). A seroprevalence of 0.8% (95% CI = 0.2-2.1%) was found among persons aged less than 15 years, and a seroprevalence of 1.3% (95% CI = 0.4-2.9%) was found among persons aged 15-24 years. On the other hand, among persons aged 25 years and over (who were born before the expanded programme on immunization [EPI]), a seroprevalence of 6.3% (95% CI = 5.8-6.8%) was found. Pockets of unvaccinated individuals were identified. CONCLUSION: The present study has documented the efficacy of vaccination in protecting against HBV infection. It also identified the presence of pockets of unvaccinated persons requiring further investigations. Aggressive health education programmes and 'catch-up' mass vaccination of those aged over 25 years is mandatory.

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PURPOSE: To compare the performance of two indirect enzyme-linked immunosorbent assays (ELISA) detecting Helicobacter pylori (HP)-specific IgG antibodies in serum and saliva with endoscopic observations and histologic findings of biopsies from dyspeptic patients, in an area of high HP prevalence. MATERIALS AND METHODS: Sera, saliva and antral biopsies were obtained from 55 dyspeptic patients. IgG antibodies against HP were assayed in sera and saliva utilizing two indirect ELISAs. Biopsies were processed according to standard procedures in order to detect histological changes and the presence or absence of Helicobacter pylori. Laboratory data thus obtained were compared and statistically analyzed. RESULTS: Forty-two (76.36%) biopsies were positive for HP. The organisms were detected in 4 of 16 (25%) cases with normal endoscopic findings, in all 16 cases of gastritis and in 22 of the 23 (95.6%) cases of duodenal ulcers (DU). Serum and saliva HP-specific IgG antibodies were detected in 4 normal cases with positive biopsies, in 12 and 14 cases of gastritis, respectively, and in all 22 (100%) biopsy positive cases of DU. The sensitivities of the serum and saliva tests were 90.5% and 95%, respectively, while the specificities were 84.5% and 70%, respectively. CONCLUSION: Due to their high sensitivity and specificity in diagnosing HP-associated DU and gastritis, serum and saliva antibody testing seems to offer a valuable alternative to invasive procedures especially in areas of high HP prevalence such as ours; saliva antibody testing is simple and practical especially in children and in difficult patients who resent venipuncture.

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We investigated the etiology of acute sporadic viral hepatitis in southern Saudi Arabia in a series of 132 patients admitted with acute viral hepatitis. Of these cases, 108 (81.8%) were due to acute hepatitis A virus infection, of which 11 (8.3%) patients had been previously exposed to hepatitis E virus, and another 10 (7.6%) were chronic carriers of hepatitis B virus. Three cases (2.3%) were acute hepatitis B virus infection. The overall prevalence of hepatitis E IgG antibodies was found to be 9.1%. The remaining 21 (15.9%) patients were tested for hepatitis E IgM, EBV-VCA IgM and hepatitis C IgG antibodies by sensitive enzyme immunoassays. In none of them could hepatitis E IgM, EBV-VCA IgM or hepatitis C IgG antibodies be demonstrated, and these patients were thus considered as acute non-A, non-B hepatitis. Acute hepatitis C virus infection, however, could not be ruled out from this group. We therefore concluded that the majority of clinically apparent viral hepatitis cases were due to HAV, while HBV accounted for a small proportion of the cases. Clinically apparent HEV infection does not appear to be common in the population studied, since even those with serologic evidence of previous exposure to HEV did not recall a history suggestive of acute viral hepatitis.

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Seventy-nine patients presenting with acute epididymo-orchitis (AEO) were prospectively analyzed in order to study the etiology and pattern of the disease. Bacteriological, serological, biochemical, imaging, and endoscopic studies were undertaken to look for urinary tract infection (UTI), brucellosis, gonorrhea, diabetes mellitus (DM), bladder outflow obstruction (BOO), and other urinary tract pathology (UP). Thirty-nine patients also underwent, on their urethral scrapings, the direct immunofluorescence test with monoclonal antibodies (DIF) for Chlamydia trachomatis. The mean age was 44 +/- 20.4 years (median = 40 years) and 43% of the patients were married. Only one patient had urethritis, which nongonococcal. Thirty-five percent presented with pyrexia and only one had brucellosis. Fifty-three percent had significant pyuria but only 22 patients (285) had bacteriuria and E. coli was the etiological agent in 19/22 patients (86%). Eleven out of 39 patients (28%) were positive for Chlamydia trachomatis. BOO, UP, and DM were encountered in 25%, 12.5% and 10%, respectively, but no obvious cause was detected in 26 (33%) patients. Recurrent AEO, abscess formation and bacteremia occurred in 21.5%, 4%, and 1%, respectively. Recurrent AEO was significantly more common in married patients than in single patients (P<0.05) and BOO was significantly more common in patients above the age of 50 years. It is concluded that an underlying cause of AEO could be identified in only two-thirds of the patients. In the remaining one-third, the etiology continues to be obscure and investigations for viral and fastidious infections may be of help in future studies. Endoscopy and urodynamic studies for BOO can be restricted to the elderly patients to cut down the cost of management of this fairly common emergency.

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A synthetic peptide corresponding to the trypsin cleavage site on the 84 k protein of bovine rotavirus was synthesized (VP4-peptide). This synthetic peptide could be cleaved by trypsin and therefore possessed the enzyme binding site present on the authentic protein. Further proof that this peptide mimicks the authentic trypsin cleavage site was the specific reaction of anti-peptide serum with the 84 k protein. The reaction of anti-peptide serum with infectious virus neutralized infectivity thereby supporting the biological importance of this site. Another interesting characteristic of this peptide was its ability to bind to the nucleocapsid protein resulting in a laddering effect on the nucleocapsid monomer (45 k), dimer (90 k) and trimer (135 k) [Gorzilia et al., J. Gen. Virol. 66, 1889-1900 (1985); Sabara et al., J. Virol. 53, 58-66 (1985); Sabara et al., J. Gen. Virol. 67, 201-212 (1986)]. Definitive proof of binding was provided by the fact that the increments in the ladder corresponded to the molecular weight of the synthetic peptide and that anti-peptide serum specifically reacted with the ladder formations. The laddering of the nucleocapsid could be eliminated by incubation with trypsin thus further supporting the formation of a synthetic peptide-nucleocapsid complex. Due to the ability of the peptide to bind to trypsin and to the nucleocapsid protein its biological activity was investigated. It appeared that increasing concentrations of the peptide reduced the rate of virus plaque formation, thereby suggesting that virus replication was inhibited. These results illustrate two features of this synthetic peptide which warrant further investigation; (1) its capacity to mimic an enzyme cleavage site and, (2) its ability to complex tightly to another protein. In protection-challenge experiments performed using a murine model, animals immunized with VP4-peptide provided protection passively, to neonates suckling on the immune dams, against a virulent rotavirus. The potential applications of this peptide in rotavirus diagnosis, therapy and synthetic peptides based vaccine is discussed.

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Synthetic peptides derived from bovine rotavirus C-486 (BRV) outer capsid (VP7 and VP4) and inner capsid (VP6) proteins were tested to evaluate their ability to prime and induce an anti-rotavirus antibody response. Peptides corresponding to the amino acid residues 232-255 of VP4 (VP4-peptide), 275-295 of VP7 (VP7-peptide) and 40-60 of VP6 (VP6-peptide) of BRV were chemically synthesized. These peptides were coupled to carrier proteins (either keyhole limpet haemocyanin (KLH) or recombinant rotavirus inner capsid protein-VP6 assembled into virus-like particles (VP6-carrier) were used as carrier to link the synthetic peptides under study), and the resulting conjugates were used to immunize rotavirus seronegative mice. An enzyme-linked immunosorbent assay (ELISA) was used to determine anti-peptide and anti-rotavirus antibody titres in serum samples collected after immunization. All peptides were immunogenic in mice and induced the production of anti-peptide antibodies, but with the exception of VP6-peptide they were not able to induce anti-rotavirus antibodies as measured by ELISA. Western blot analysis indicated that antibodies against each peptide were able to react with the respective authentic viral proteins of various rotavirus serotypes. To determine if a peptide-primed animal would respond to native viral proteins, animals were subsequently injected with purified BRV. A rapid and high anti-rotavirus antibody titre, in addition to a rise in anti-peptide antibody titre, was observed in peptide-primed mice. Furthermore, the sera obtained from these mice neutralized the virus under in vitro conditions. The significance of these results in relation to a potential rotavirus synthetic peptide-based vaccine is discussed.

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Ohio HeLa cells in multichamber slides were inoculated with nasal samples from patients presenting with common cold symptoms and incubated at 33 degrees C with gentle shaking for 48 hours. The cultures were fixed with cold acetone, and viral antigens were detected by immunofluorescence using an antirhinovirus type 2 (HRV-2) polyclonal serum. Of 158 samples, 58 (36.7%) and 57 (36%) were positive for HRV by virus isolation (confirmed by acid lability test) and by culture-amplified immunofluorescent (CAIF) test, respectively. The correlation between the two tests was highly significant (P = 0.0001). Nasal washings or nasal/throat swabs were equally suitable for detecting virus by isolation but not by CAIF. On the other hand, nasal washings were better than nasal/throat swabs for detecting HRV by CAIF. In an ELISA system, the polyclonal anti-HRV-2 serum recognized a rhinovirus antigen expressed in situ within 48 hr postinfection by all the 11 HRV serotypes investigated. However, 60 hr postinfection, the anti-HRV-2 serum recognized only homologous and closely related HRV antigens. These results suggest that a rhinovirus "common" antigen may be expressed some 48 hr after infection of Ohio HeLa cells with rhinoviruses. The CAIF test provides a sensitive, rapid and reliable procedure to detect wild-type rhinovirus infection as well as a clear alternative to detection by isolation.

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IgM antibodies specific for cytomegalovirus (CMV) were demonstrated in 15 (2.6%) of 575 umbilical cord sera obtained from newborns in Kuwait. Some 93% and 50% of these CMV-IgM positive cord sera displayed markedly raised (more than normal mean +2 S.D.) content of total IgM and IgA respectively. In contrast, only 0.2 and 1.8% of the CMV-IgM negative cord sera had elevated total IgM and IgA, respectively. Rheumatoid factor (RF) was demonstrable, at concentrations of 30 IU/ml or more, in 67% of the CMV-IgM positive as compared with 3.2% of the CMV-IgM negative sera whereas interferon alpha was found in the serum of only one of these infants. These results indicate that raised total immunoglobulin, in particular IgM, concentrations and the detection of RF in cord blood are useful non-specific markers for the identification of congenital CMV infection.

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A hybridization assay using a biotinylated DNA probe was compared to both ELISA and direct isolation methods for detecting human cytomegalovirus (HCMV). The biotin labeled HCMV AD 169 HindIII-O-DNA fragment was used in a dot-blot assay to screen for the presence of HCMV in 186 urine specimens obtained from kidney transplant patients. The biotinylated HCMV HindIII-O probe could detect 3 log10 TCID50 units of HCMV. Urine specimens were also examined for the presence of HCMV by either ELISA or direct isolation of virus in tissue culture. The HindIII-O fragment detected 12 of 20 culture positive samples (sensitivity, 60%). There were 5 samples which were probe positive and cell culture negative (specificity, 97%). The ELISA assay also detected 12 of 20 culture positive samples (sensitivity, 60%). Eight samples were ELISA positive, cell culture negative (specificity, 95%). Seven specimens were positive by all three criteria. Five specimens which were both ELISA positive and probe positive were cell culture negative. The ELISA positive, probe positive, culture negative specimens originated from patients who gave a culture positive specimen within 10 days of the original sample. The combination of probe and ELISA assays detected 16 of the 20 culture positive specimens (sensitivity, 80%). The combined use of biotinylated DNA probes and ELISA allows the detection of HCMV in urine specimens with good sensitivity and specificity.

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The present study describes, for the first time, the clinical and the ultrastructural findings of a rare case presented with concurrent conjunctival infection of Rhinosporidium seeberi and a papovavirus. In contradistinction to previous reports, the present case lacked the characteristic granulomatous inflammatory reaction of rhinosporidiosis. This finding, together with the frequent recurrence of the lesion, led us to postulate the presence of a Local Acquired Immune Deficiency State (LAIDS). This Local AIDS may be caused by an immunosuppression mechanism which is probably mediated by papovavirus.

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Some factors influencing the detection of human cytomegalovirus (HCMV) in urine were investigated employing 2 enzyme-linked immunosorbent assays (ELISAs); one utilised anti-CMV DNA polymerase while the other anti-CMV mouse monoclonals as the detecting antibodies. The use of anti-CMV DNA polymerase was found to be superior in detecting HCMV in both urine and tissue culture fluids than anti-CMV monoclonals. Furthermore, alkaline phosphatase conjugates produced much lower background than did peroxidase conjugates. In reconstruction experiments, the extremes of pH in the urine clearly had an adverse effect on the detection rate of extracellular virus. pH correction of urines to neutrality improved the detection rate considerably. On the other hand, pH correction had little effect on the detection rate of intracellular HCMV in urine, although it was improved when specimens were subjected to repeated cycles of freeze-thawing, ultrasonication, and storage at 4 degrees C. It was concluded that, in addition to the factors investigated which all appear to affect virus detection rate, there may well be additional factors that interfere with CMV detection in the urine by ELISA particularly with intracellular virus.

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One thousand five hundred and fifty-four Arab women were screened at delivery for the presence of hepatitis B virus (HBV) antigenaemia in their sera. Forty-five or 2.9% were found to be positive. Only three of 41 (7.3%) of these hepatitis B surface antigen-positive (HbsAg) mothers were found to be positive for the presence of hepatitis B e antigen (HBeAg), 27 (65.8%) had anti-HBe and the remaining 11 (26.8%) had neither HBeAg nor its corresponding antibody. These results, therefore, predicted a low rate of transmission of virus from mother to newborn. Follow-up for 4-13 months after delivery on 14 of these HBsAG-positive mothers and their infants indicated that in only one infant born to an HBeAg-positive mother did HBV antigenaemia develop. Another infant died from undetermined causes. Therefore, HBV perinatal transmission among Arabs, unlike that among populations in Southeast Asia, does not appear to contribute in an important way to the pool of carriers in this population.

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Three-hundred and sixty-three stool specimens from patients with diarrhoea were examined for rotaviruses to compare the sensitivity of the pseudoreplica technique (PSD-EM) to that of high-speed centrifugation EM (HSC-EM) in relation to a commercially available (Rotazyme, Abbott) enzyme-linked immunosorbent assay (ELISA). In ELISA-positive cases, both methods were of equal sensitivity. However, in borderline (+/-) and ELISA-negative specimens, PSD-EM detected 31 of 48 (64.6%) and 18 of 229 (8%) positive specimens respectively, compared to only 22 of 48 (45.8%) and one of 229 (0.4%) positives detected by HSC-EM. PSD-EM detected a significantly higher number of positives compared to HSC-EM (p less than 0.05). In view of its simplicity, sensitivity and the fact that a relatively large number of specimens could be processed compared to HSC-EM, we consider that PSD-EM is a much better procedure for routine screening and diagnosis of viral gastroenteritis than HSC-EM.

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From two major hospitals in Kuwait 502 sera were randomly selected from patients during the period December 1979 to October 1982. Serological investigations demonstrated Flavivirus activity in the area and antibody to Congo/Crimean haemorrhagic fever virus was found in 4% of the samples. Clinical data indicate that some cases may have been due to recent Congo/Crimean virus infection.

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Yellow fever, dengue (types 1, 2 and 4), Chikungunya, Rift Valley fever, Ebola, Marburg, and Lassa viruses were inoculated into susceptible cell cultures and daily investigated by indirect immunofluorescence (IFA) and electron microscopy (EM) with a view to achieve an early detection-identification of these agents. Compared to the other cell lines tested (Vero, BHK-21 and Aedes albopictus), CV-1 cells were found to be more sensitive. Viral antigens were detected by IFA from a few hours post inoculation (CHIK and RVF) to a maximum of 3 days (YF and EBO). For most of the viruses studied, the cytopathic effect (CPE) commenced 2-3 days after the detection of viral antigens. Virus particles were detected by EM only in the case of EBO, MBG and LAS, before any CPE was observed in cell cultures.

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Bangui, Bobaya, Kowanyama, Upolu and Zinga are enveloped spherical RNA viruses sensitive to ether and acid pH; morphologically resembling Bunyaviridae, their diameters range from 90 to 100 nm and their bouyant density is 1.17 to 1.18 g/ml in sucrose. St. Floris, a bunya-like virus, serologically related to Rift Valley Fever, has a diameter ranging from 90 to 110 nm. Triniti, Zingilamo, IPYM 120 and virus strain AnB4268 are enveloped spherical RNA viruses sensitive to ether and acid pH, have diameters of 65, 55, 55 and 60 nm and bouyant densities of 1.18, 1.24, 1.20 and 1.18 g/ml in sucrose, respectively; morphologically they resemble Togaviridae. Salanga is a poxvirus measuring 190 X 225 nm. Virus strain AnY1444 is a spherical, non-enveloped RNA virus measuring 85 nm, morphologically resembling Reoviridiae; it is restraint to both ether and acid pH and shows two-peak densities of 1.32 and 1.36 g/ml in caesium chloride. Bangoran, Keuraliba and Yata resemble Rhabdoviridae measuring 60 X 175, 65 X 195 and 60 X 185 nm, respectively.

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