Birefringent filamentous organelle in BHK-21 cells and its possible role in cell spreading and motility.

A birefringent structure consisting of a mass of filaments, 100 to 125 angstroms in diameter, appears at certain times during the spreading of a BHK-21 cell in culture. It is involved in the formation of the birefringent streak found in fully spread cells. The structure may be in part responsible for various aspects of cell motility.

An enzyme-linked immunosorbent assay for antibodies to the envelope glycoproteins of divergent strains of HIV-1.

We have developed an enzyme-linked immunosorbent assay (ELISA) specific for antibodies to the envelope glycoproteins gp120 and gp160 of HIV-1. An antibody to a conserved epitope on gp120 is adsorbed to a solid phase and used to capture gp120 and/or gp160 from solution. This may be purified recombinant protein or in simple, non-denaturing detergent extracts of different strains of HIV-1. Human serum antibodies bound to the captured antigen are subsequently detected with an anti-human antibody conjugated to alkaline phosphatase, and the AMPAK ELISA amplification system (Novo BioLabs, Cambridge, UK). With this procedure, antibodies can be detected that recognize gp120 from a wide range of divergent HIV-1 strains. The ELISA is sufficiently sensitive to detect env antibodies in sera from HIV-positive individuals at dilutions of 1:300,000. No repeatable false-positives were detected in a screen of 250 normal serum samples. Env antibodies were detected in all 37 strongly HIV-positive sera tested, and in four sera that were borderline or weakly positive in commercial ELISA. However, 55 sera positive in commercial ELISA but unconfirmable by Western blot ('ambiguously' positive) did not contain detectable env antibodies.

Genome analysis of human rotaviruses by oligonucleotide mapping of isolated RNA segments.

The genomes of adult diarrhoea rotaviruses isolated in different parts of China during winter outbreaks in 1983 and 1984 were compared by segmental oligonucleotide (ON) mapping. The RNA profiles of most of the isolates were indistinguishable but it was found that some corresponding RNA segments had identical or very closely related ON maps whereas others differed considerably. This finding can be taken to suggest that the strains compared may be genetically related by a natural reassortment event. The genomes of cocirculating group A rotaviruses isolated in Scotland during winter outbreaks in 1981/82 were also compared. The ON maps of corresponding RNA segment differed extensively irrespective of whether or not the segments comigrated on gels.

Immunodominant epitopes of HIV-1 p17 and p24.

Immunodominant antibody-binding sites were mapped using overlapping synthetic peptides of the structural proteins p17 and p24 of human immunodeficiency virus type 1 (HIV-1). Using sera from HIV-1-infected individuals at a variety of disease states, three major epitopes were identified within p17 and one within p24. Antibodies which recognized these epitopes were present in all risk groups throughout all stages of HIV infection, regardless of the presence of high levels of serum p24 antigen.

Serological markers of hepatitis B in patients with alcoholic liver disease: a multi-centre survey.

In a study of 195 patients derived from five centres in northern Britain and with histologically confirmed alcoholic liver disease we have found an increased prevalence of serological markers of hepatitis B. This increased prevalence was found in each of the five centres; the overall frequency ranged from 11% sero-positivity in fatty liver, 12% in alcoholic hepatitis and 27% in cirrhosis.

An assessment of the sensitivity of three methods for the detection of rotavirus.

A comparison was made of the sensitivity of a current commercial ELISA for detecting rotavirus in faecal specimens with the more complex, technically demanding systems of electron microscopy and polyacrylamide gel electrophoresis. Even after modification, the ELISA failed to detect 22% of specimens with particles identifiable by electron microscopy. Polyacrylamide gel electrophoresis failed to identify 2 out of 50 specimens with particles present but did distinguish 2 group C rotaviruses.

Evidence of past delta co-infection with acute hepatitis B in intravenous drug abusers in the west of Scotland.

Two hundred sera from asymptomatic hepatitis B surface antigen (HBsAg) negative intravenous drugs abusers (IVDAs) were tested for delta antibody and antiHBc to determine the number of delta co-infections occurring with acute hepatitis B infection in this group. Of the 200 sera, 15 were positive for antidelta and 143 for antiHBc, giving a delta co-infection rate of 10.5%. Laboratory records were consulted to ascertain which IVDAs had acute hepatitis B. Of 29 patients who submitted serum when HBsAg-positive, 10 are currently antidelta-positive. There was no evidence of loss of delta antibody after resolution of acute co-infection. The majority of those with delta co-infection had sought medical attention (10 of 15), whereas only a minority (19 of 128) with only hepatitis B did so. These results suggest that delta co-infection more often results in significant clinical illness than acute hepatitis B alone.

A cumulative review of studies on travellers, their experience of illness and the implications of these findings.

A cumulative review of illness experienced by 13,816 travellers returning to Scotland since 1977, shows an overall attack rate of 36%. Alimentary complaints predominated; 18% of travellers had these alone and a further 10% had other symptoms as well as their gastro-intestinal disorder. Higher attack rates were noted in those taking package holidays. Inexperience of travel, smoking, more southerly travel and younger age (particularly those between 20- and 29-years-old) were other contributing factors. A similar pattern emerged from a I year study of hospital in-patients with travel related admissions. Serological studies of 470 travellers showed that 20% had incomplete immunity to poliomyelitis; 25% of those tested (312 travellers) had serological evidence of typhoid immunisation, I.9% (of 760 travellers) had antibodies to Legionella pneumophila, 64% (5II travellers tested) had antibodies to hepatitis A, 87% (288 tested) had adequate levels of tetanus antitoxin but only 40% of the 225 travellers tested had adequate levels of diphtheria antitoxin. Amongst a subgroup of 645 travellers the travel agent was the most frequently consulted source of pre-travel health advice. This carries particular significance for the dissemination of relevant advice in view of the inadequacies found from study of the health information in travel brochures. These findings, viewed against the perspective of the continuing growth in international travel, means that travellers, the medical profession, the travel trade, health educators, global health agencies and health authorities in those countries accepting and encouraging tourists, will be required to recognise the health implications of further tourism development if this problem of illness associated with travel is to be brought under control.

HIV testing among injecting drug users in Glasgow.

The use of saliva rather than blood for epidemiological studies of HIV prevalence, especially among injecting drug users, has several practical advantages. In a cross-sectional, behavioural and prevalence study among drug users in Glasgow during 1990, salivary samples were therefore obtained by the use of salivettes. Such samples were requested for anonymous anti-HIV testing from 498 persons in locations varying from residential rehabilitation centres to the open streets. Of this number, 35 refused to give a sample, resulting in a compliance rate of 93%. Of the 463 salivettes received by the laboratory, eight were found to be dry. Of the remaining 455 specimens, eight were found to be positive for HIV-1 antibody by means of an IgG antibody capture ELISA, so giving a prevalence rate of 1.8%. The results of testing saliva and blood spot samples collected at the same time on filter paper from 98 persons for HIV-1 antibody were 100% concordant. The study confirms the experience of others that specimens of saliva are easy to collect under variable conditions by non-medical staff and demonstrates that the salivette can provide an HIV antibody test result the same as that obtained from a blood spot. The prevalence of HIV antibody determined in this study is similar to that of other studies taking place in the city during the same period of time.

Distribution of HIV and acute hepatitis B infection among drug injectors in Glasgow.

This study compared the distributions of known human immunodeficiency virus (HIV) and acute hepatitis B virus (HBV) infection among drug injectors in Glasgow over a 3.5 year period. Data were obtained from all relevant laboratory request forms submitted to Glasgow's 3 virology laboratories during the period 1 January 1986 to 30 June 1989. The overall prevalence of HIV among those tested was 3.7% (66/1786). There were 125 cases of acute HBV infection. The male:female ratios for HIV and acute HBV were 1:1 and 2:1, respectively. Thirty-four per cent of persons with HIV were aged under 21 years compared with 53% with acute HBV. Three out of 10 areas of the city accounted for 92% of HIV infection but only 66% of acute HBV infection. HIV infection was not detected among drug injectors in 4 areas of the city but at least 2 cases of acute HBV infection were recorded in all 10 areas. The geographical and age distribution of acute HBV infection in Glasgow suggests that the potential for future spread of HIV among drug injectors remains considerable.

Hepatitis C virus in saliva of haemophiliac patients attending an oral surgery unit.

This study determined the frequency with which hepatitis C virus (HCV) could be detected in the saliva of 21 HCV-seropositive haemophiliac patients attending an Oral Surgery Unit. All sera were positive for HCV RNA by the polymerase chain reaction (PCR). Six of the patients were also HIV antibody positive. Saliva was collected both by spitting into a Universal container (whole saliva), and by means of Salivettes. Following RNA extraction from saliva specimens and synthesis of cDNA, nested PCR was performed. Amplified DNA was detected by agarose gel electrophoresis and ethidium bromide staining. Overall, HCV was detected in saliva from 10 of the subjects (8 HIV seronegative and 2 HIV seropositive) but there was not complete concordance between the Salivette specimens and normal whole saliva. Analysis of pellet and supernate fractions from whole saliva produced similar discrepancies. Repeat runs of PCR for HCV following freezing and thawing of the initially positive saliva specimens were unsuccessful. It was concluded that HCV is present in the saliva of some haemophiliac patients. However, careful optimisation of sample handling and storage methods and of PCR technique are required before the true prevalence of HCV shedding in saliva can be determined.

Outbreak of HIV infection in a Scottish prison.

OBJECTIVE--To investigate the possible spread of HIV infection and its route of transmission among prison inmates. DESIGN--In response to an outbreak of acute clinical hepatitis B and two seroconversions to HIV infection, counselling and testing for HIV were offered to all inmates over a two week period in July 1993. Information was sought about drug injecting, sexual behaviour, and previous HIV testing. SETTING--HM Prison Glenochil in Scotland. SUBJECTS--Adult male prisoners. MAIN OUTCOME MEASURES--Uptake of HIV counselling and testing; occurrence and mode of HIV transmission within the prison. RESULTS--Of a total 378 inmates, 227 (60%) were counselled and 162 (43%) tested for HIV. Twelve (7%) of those tested were positive for antibody to HIV. One third (76) of those counselled had injected drugs at some time, of whom 33 (43%) had injected in Glenochil; all 12 seropositive men belonged to this latter group. Thirty two of these 33 had shared needles and syringes in the prison. A further two inmates who injected in the prison were diagnosed as positive for HIV two months previously. Evidence based on sequential results and time of entry into prison indicated that eight transmissions definitely occurred within prison in the first half of 1993. CONCLUSION--This is the first report of an outbreak of HIV infection occurring within a prison. Restricted access to injecting equipment resulted in random sharing and placed injectors at high risk of becoming infected with HIV. Measures to prevent further spread of infection among prison injectors are urgently required.

Hepatitis A in Scotland--is it a continuing problem?

The prevalence of anti-HAV in blood donors in West Scotland and in children admitted to a Glasgow hospital was determined. By the age of five years, 16% of the children had antibody and at 15 years, 30%. In adults, prevalence continued to rise with age, with 78% of those over 40 years showing evidence of past infection. Cases of acute hepatitis A in West Scotland have declined since 1983. At present the peak age group for infection is 25-34 years whereas in the early 80s the peak group was five to 14 years.

Acute hepatitis A infection in West Scotland.

In 1979, 43 cases of acute hepatitis A infection were diagnosed by the presence of hepatitis A specific IgM antibodies in acute phase sera. The majority (34) were in patients under 30 years with 13 in children under 10 years: 23 were males. Few cases occurred in the winter months, most in autumn, with a peak in September. A total of 17 cases had a history of recent travel abroad, and six of contact with a case of jaundice/hepatitis. There were 11 cases in members of the immigrant community.

Hepatitis B in adolescence and middle-age.

In 1983 304 serum samples, and in 1984 432 serum samples submitted to the Hepatitis Reference Laboratory, Ruchill Hospital, Glasgow were found to be positive for HBsAg by radio-immunoassay. Of these, 37 in 1983 and 50 in 1984 were from persons less than 18 years, while 38 and 46 respectively were from persons greater than 39 years. This increase from 1983 to 1984 was due to more acute infections among males. In males less than 18 years, infections were related to drug abuse, whereas in men greater than 39 years sexual transmission appeared to be the main source. Women greater than 39 years may be at increased risk of infection from other members of the household. A finding of HBsAg in a person greater than 39 years is likely to be from an acute infection as from a carrier.

Acute hepatitis a in West Scotland in 1981. A change in pattern.

In 1981, 151 cases of laboratory confirmed Hepatitis A infection were diagnosed in West Scotland, an increase of more than three-fold over both 1979 and 1980. The majority (54%) were in children under 15 years of age, case numbers then declining with age, apart from a rise in numbers in the 21-30 age group. Almost all children infected were Scottish children. Significant numbers were associated with contact with a known case (25%) or travel abroad (16%). Few cases were diagnosed in the first five months of the year. This upsurge in laboratory-diagnosed cases was associated with an increase in notifications of viral hepatitis to the Registrar General for Scotland for the first time in 10 years.

Prevalence of maternal HIV infection in Scotland based on unlinked anonymous testing of newborn babies. Update.

In January 1990, unlinked anonymous testing of Guthrie cards for HIV antibody commenced in Scotland. Ethics Committee approval allowed testing of 99.6% of Scottish births. Twenty-one mothers spontaneously refused to allow testing of their baby's blood. Samples were coded by district postcodes. For 1990 through 1991, eluates of 132,531 dried blood spots were initially tested for HIV-1 antibody with the Fujirebio technique. Of the 49 positive samples 38 were confirmed to be positive by enzyme-linked immunosorbent assay and western blot (seroprevalence 0.3 per 1000). Thirty-five of 38 samples came from large metropolitan areas in Scotland. Prevalences were 2.0 per 1000 for Edinburgh city, 0.7 per 1000 for Dundee and Aberdeen, 0.15 per 1000 for Glasgow and 0.05 per thousand for all other areas in Scotland. Recent spread of HIV infection to Aberdeen may have occurred. These figures do not support an overall increase of HIV infection in childbearing women in Scotland.

Liver dysfunction in haemophilia.

Liver function was studied in 139 of 291 haemophiliacs known to a single Regional Haemophilia Centre including patients with classical haemophilia, Christmas disease and von Willebrand's disease. In 57 patients, six-monthly liver function tests over a five year period were also available. Thirty-nine of the 139 patients had had jaundice or hepatitis and 56 had a positive test for HBsAb in the blood although few of these had had an identifiable clinical illness. Fifty-eight haemophiliacs had elevated serum aminotransferases at the time of study, but the five year review revealed only six patients who had had persistently abnormal results, although none had clinically evident liver disease. Liver dysfunction was unrelated to a history of hepatitis, to a positive HBsAb test, or to age, type of haemophilia, factor level or frequency of factor replacement treatment. Abnormalities of liver function in haemophilia appear to be unrelated to past or present hepatitis B infection in most cases and may not be related to any single transmitted infectious agent.

Spread of maternal HIV infection in Scotland from 1990 to 1992.

In Scotland since January 1990, unlinked anonymous testing of Guthrie cards has documented maternal HIV-1 antibody in neonatal blood. District postcode and quarter year of birth determined prevalence and spread of infection. The Fujirebio particle agglutination assay screened for HIV-1 antibody, with confirmation by ELISA and full western blotting. Births to known HIV infected women were reported to the Royal College of Obstetricians and Gynaecologists. 0.3/1000 childbearing women were infected with HIV-1 with no significant increase from 1990 to 1992. Spread of infection from 11 to 26 districts has occurred. In 1990, 74%(14/19) of HIV positive deliveries were known to obstetricians falling to 33%(7/21) in 1992. Spread of HIV-1 infection has occurred to mothers who live outside closely defined areas and who do not belong to recognised high risk groups. In Scotland, two thirds of mothers and their infants will not receive early prophylactic care for their HIV disease.

Occupational infection with hepatitis C virus in the healthcare setting.

Our understanding of the types of hepatitis described previously as non-A, non-B hepatitis has been revolutionized by the discovery of two new viruses, hepatitis C virus (HCV) and hepatitis E virus. HCV is transmitted parenterally, and poses a potential occupational hazard to health care workers, including dental staff. No vaccine is currently available, and it is important that an assessment of infection risk is made available to clinicians.