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J V Parry

Publications and source records attributed to J V Parry.

At least 73 records · Page 4Linked to original sources
PubMed1995

Trends in female sexual behaviour and sexually transmitted diseases in London, 1982-1992.

OBJECTIVE: To measure changes in female sexual behaviour, including condom use, and their relationship with the incidence of sexually transmitted and other genital diseases in women during the decade 1982-92. DESIGN: A prospective series of cross-sectional surveys of sexual behaviour reported by a standardised self-administered questionnaire in new patients who presented for screening and diagnosis. SETTING: A genitourinary medicine clinic in West London. SUBJECTS: 4089 consecutive newly attending patients who completed sexual behaviour questionnaires during 1982, 1987, 1989 and 1992. MAIN OUTCOME MEASURES: Trends in socio-demographic status, sexual behaviour, condom-use, sexually transmitted diseases and other genital infections diagnosed by routine clinical and laboratory methods. RESULTS: Women reported significantly increasing condom use (from 3.6% to 20.7%) and decreasing oral contraception (from 51.2% to 40.1%), but the proportion who used no contraception (23.6% to 24.7%) and the proportion who had never been pregnant (58.3% to 59.9%) remained similar. Numbers of sexual partners in the preceding year decreased (p < 0.001) and an increasing proportion of women practised oral intercourse (p < 0.001). During the same period, there was a progressive decline (p < 0.001) in the incidence of gonorrhoea, chlamydial infection and trichomoniasis by approximately two-thirds. However, the incidence of vaginal candidosis (p < 0.001), bacterial vaginosis (p < 0.001) and genital warts (p < 0.01) increased. CONCLUSIONS: Increasing use of condoms for vaginal intercourse with both regular and non-regular partners has been associated with a decrease in the incidence of gonorrhoea, chlamydial infection and trichomoniasis. There was also an increase in the practice of fellatio and a change in the spectrum of STD and other genital infections with little net reduction in morbidity. HIV infection showed no evidence of heterosexual spread.

Adolescent↗
PubMed1994

Survey of human immunodeficiency virus infection among pregnant women in England and Wales: 1990-93.

We report on the first four years (1990-93) of a survey within the national HIV prevalence monitoring programme. The survey's objective is to monitor the prevalence of infection with the human immunodeficiency virus (HIV) in pregnant women in London and elsewhere in England. The survey--based in forty centres that offer antenatal care in London, Greater Manchester, West Yorkshire, and adjacent non-metropolitan areas--uses repeated cross sectional serosurveillance for anti-HIV-1 and 2 and the unlinked anonymous test method on blood left over from specimens collected for antenatal screening for immunity to rubella. The seroprevalence of HIV-1 ranged from 0.007% (1 in 14,530) in non-metropolitan areas, to 0.011% (1 in 8790) in metropolitan areas outside London, and 0.23% (1 in 440) in London. Evidence of HIV-2 infection was found in only four specimens, in London (1 in 50,300). The seroprevalence of HIV-1 in London varied more than tenfold between centres, from 0.03% (1 in 3190) to 0.51% (1 in 200). The highest prevalence of infection was in London in women aged between 20 and 30 (0.30%; 1 in 335). The seroprevalence in London centres rose from 0.18% in 1990 (1 in 560) to 0.26% in 1993 (1 in 390) and the rise was significant in all age groups. If voluntary confidential HIV testing (with counselling) among pregnant women in England were to be promoted, its cost effectiveness would be greater if focused on particular centres that provide antenatal care in London.

Adult↗
PubMed1994

Thirteen current anti-HIV-1/HIV-2 enzyme immunoassays: how accurate are they?

The sensitivity and specificity of 13 current anti-HIV-1/HIV-2 screening enzyme immunoassays (EIA) for the detection of anti-HIV in human serum or plasma were investigated by testing against a panel of 454 well-characterised serum or plasma specimens. The panel included specimens confirmed to contain anti-HIV-1 (n = 96), anti-HIV-2 (n = 26), or low levels of anti-HIV (n = 44) as well as specimens collected during HIV-1 seroconversion (n = 73). Specimens from unselected blood donors (n = 80) and samples from patients with a range of pathological conditions (n = 135) were also included. Observed sensitivities ranged from 96.9% (Biochrom, UBI, and Vironostika) to 100% (Biotest, Cambridge Biotech, IAF Biochem, Ortho, and Vidas). For the seroconversion specimens, Biotest, Cambridge Biotech, Ortho, and Vidas were most sensitive. Observed specificities ranged from 89.9% (UBI) to 100% (Biochrom and Ortho). One assay (Ortho HIV 1+2 EIA) achieved maximum sensitivity and specificity, and was one of four assays to detect anti-HIV-1 early in seroconversion. The accuracy of several of the other EIAs was also quite adequate, so additional factors such as convenience and cost can be considered when choosing an assay from the group evaluated.

Evaluation Studies as Topic↗
PubMed1994

Detection of antibody to HIV in saliva: a brief review.

BACKGROUND: The possibility that saliva could be used for HIV screening and diagnosis has been known since 1986. Despite the obvious advantages over venepuncture of ease of collection, safety, compliance and cost, interest in salivary testing has grown relatively slowly. Several studies have demonstrated that salivary anti-HIV testing can be highly accurate, particularly if specimen collection procedure are optimal. OBJECTIVE: To review current knowledge about the detection of anti-HIV in oral fluids, with an emphasis on the identification of optimal procedures. STUDY DESIGN: In the light of existing published data, the factors leading to accurate salivary diagnosis of HIV infection were identified and reviewed. RESULTS: To achieve the best results it is essential to collect oral fluid specimens that are rich in IgG. Most IgG in the oral cavity derives from the crevicular space between the gums and the teeth, and not from salivary glands. Available methods for collecting salivary specimens are discussed. Until these collection methods are fully validated, individual specimens or at least clinical ones found anti-HIV negative should be tested for total IgG before being reported on. There is a lack of proven confirmatory methods for salivary anti-HIV and this problem is reviewed. Salivary anti-HIV testing has been employed mostly for surveillance, but life insurance applicants are increasingly screened in this way and clinical applications are under active consideration. With appropriate safeguards, diagnostic and pre-blood donation salivary testing could be introduced shortly. The necessary technology is also available to develop rapid single-use salivary tests. This would bring anti-HIV testing closer to the patient. CONCLUSIONS: Salivary tests for anti-HIV offer advantages of convenience, economy and safety, and are more acceptable to subjects than blood tests. Further evaluation of the collection devices and assays, the introduction of safeguards against inadequate sampling and the development of suitable confirmatory assays are required. When these deficiencies have been met, salivary tests may supersede tests on serum for HIV and also other infections.

Journal Article↗
PubMed1994

Detection of anti-HIV in saliva and urine at the time of seroconversion.

To determine whether there is a delay between the appearance of anti-HIV in serum/plasma and its detection in saliva and urine, salivary and urine specimens were collected from nine individuals who, on the basis of increasing IgG anti-HIV reactivity, Western blot band patterns and presence of strong IgM anti-HIV reactivity in their serum specimens, were believed to have recently become anti-HIV-positive. Serum from 8 of these patients and 3 commercial panels of plasma specimens collected during seroconversion were diluted to mimic the low immunoglobulin concentrations present in saliva and urine and tested in Wellcozyme HIV 1 + 2 GACELISA and four commercial EIAs intended for testing serum specimens. The 9 pairs of saliva and urine specimens were collected between 4 and 43 days (median 24 days) after the first evidence of seroconversion. All were reactive by Wellcozyme HIV 1 + 2 GACELISA and gave optical density/cut off (OD/CO) ratios in the range 3.8 to 9.8 (median 5.2) for dribbled saliva and 2.4 to 10.1 (median 6.3) for urine. Salivary specimens taken with commercial collection devices gave OD/CO ratios in the range 1.6 to 10.6 (median 5.9). In the serum/plasma specimens Wellcozyme HIV 1 + 2 GACELISA detected anti-HIV at higher dilutions than the other assays, often with a 100-fold or more difference. Saliva and urine specimens were all strongly reactive by Wellcozyme HIV 1 + 2 GACELISA. We therefore predict that it would first detect anti-HIV in salivary and urine specimens at about the same time as it becomes detectable in serum/plasma but that other commercial EIAs would not.

Journal Article↗
PubMed1994

Risk behaviour and HIV prevalence in international travellers.

OBJECTIVE: To assess risk factors for infection and to determine HIV prevalence in a sample of international travellers. DESIGN: A cross-sectional survey of new patients attending a hospital outpatient clinic, and self-completion of an anonymous questionnaire on sexual behaviour prior to and during travel. Urine samples were tested for the presence of antibodies to HIV. SETTING: The Hospital for Tropical Diseases, London, UK. SUBJECTS: All new patients over a 6-month period. RESULTS: Of 782 people approached, 757 (97%) agreed to participate: 141 (18.6%) had had new sexual partners during their most recent trip abroad. Almost two-thirds of those having sex abroad did not use condoms on every occasion with a new partner, and 5.7% contracted a sexually transmitted disease (STD) during their most recent trip; 26% of men from World Health Organization Pattern I countries who had new sexual partners abroad paid for sex. Sixteen out of 731 (2.2%) participants were HIV-antibody-positive. HIV positivity was associated with being born in east, central or southern Africa, having symptoms of an STD since arriving in the United Kingdom and being treated for an STD since arrival. CONCLUSION: The rates of unsafe sex and payment for sex abroad reported by these international travellers indicate the potential for contracting and transmitting STD, including HIV, in both their foreign and domestic sexual partnerships. With the increasing HIV incidence in Asia (the most common destination for UK travellers after sub-Saharan Africa), the number of cases of HIV contracted abroad may rise in the future.

Adult↗
PubMed1993

Simple haemadherence test for the detection of class-specific immunoglobulins to hepatitis A virus.

The ability of hepatitis A virus (HAV) to agglutinate human erythrocytes was used to develop IgM and IgG antibody capture haemadherence tests (MACHAT and GACHAT). Haemadherence was dependent on the pH of the red cell suspension and was best in the pH range 5.4 to 5.8. The tests were applied to serum, urine, and saliva specimens from individuals susceptible to, or with recent or past infection with HAV. Haemadherence test reactivities were compared with results obtained with IgM and IgG antibody capture radioimmunoassay (MACRIA and GACRIA) and competitive radioimmunoassay (COMPRIA). For 339 serum specimens examined, the sensitivity and specificity of MACHAT were 98.2% and 99.6%, respectively, and of GACHAT 99.1% and 100.0%. For 303 urine specimens, the sensitivity and specificity of MACHAT were 99.1% and 100.0%, and of GACHAT 100% for both. On initial testing, accuracy on saliva specimens was considerably less. For 2,819 saliva specimens, the sensitivity and specificity of MACHAT were 85.7% and 97.2% and of GACHAT 90.4% and 94.7%. The haemadherence test is a simple, inexpensive method which is satisfactory for use on serum and urine specimens. MACHAT and GACHAT can be used for epidemiological investigations, e.g., hepatitis A outbreaks and, in conjunction with a confirmatory test, for clinical diagnostic testing.

Hemagglutination Tests↗
PubMed1993

Detection of measles, mumps, and rubella antibodies in saliva using antibody capture radioimmunoassay.

Antibody capture radioimmunoassays were developed for detecting virus specific IgM (MACRIA) and IgG (GACRIA) to measles, mumps, and rubella and used to investigate saliva as an alternative specimen to serum for diagnosis. Saliva was collected from 63 patients with measles, 19 with mumps, and 150 with rubella, which were all clinically diagnosed and serologically confirmed. Virus specific IgM was detected in 92% of measles, 75% of mumps, and 100% of rubella saliva samples collected during the first week of illness. Between 1 and 5 weeks after onset virus specific IgM was detected in 100% of saliva specimens. After the 5th week the proportion of reactive specimens declined. The specificity of the MACRIA tests was established by testing saliva samples collected from blood donors for measles (88), mumps (88), and rubella IgM (91). All of the saliva specimens tested for measles and rubella specific IgM were unreactive, 1/88 specimens tested for mumps specific IgM contained significant reactivity. Saliva specimens collected from acute cases of MMR were tested in all 3 MACRIAs. A small proportion of saliva samples contained detectable IgM of more than one virus infection. Rubella and measles specific IgG was detected in the saliva of all cases from the 4th or 5th day of illness, respectively. Detection of mumps specific IgG was less successful. We have demonstrated that virus specific IgM can be reliably detected in saliva samples collected from acute cases of measles, mumps, and rubella and identified 1-5 weeks after onset of illness as the optimum time for collection of samples.

Adolescent↗
PubMed1993

Novel assay for the detection of immunoglobulin G antihuman immunodeficiency virus in untreated saliva and urine.

Epidemiological evidence and laboratory studies indicate that human immunodeficiency virus type 1 (HIV 1) is rarely, if ever, transmitted in saliva or urine. In that both specimens are easy to collect, each may be a useful alternative to serum specimens for anti-HIV screening. A rapid, simple, and robust IgG-capture enzyme-linked immunosorbent assay (GACELISA) suitable for the detection of anti-HIV 1 and 2 in saliva and urine was developed. Following optimisation of the assay, 177 salivary and 568 urine specimens collected from individuals of known serostatus were investigated. The assay was 100% sensitive on 50 salivary (median OD/CO = 8.9) and 126 urinary (median OD/CO = 8.6) specimens collected from anti-HIV-positive patients. The specificity was 100% on 127 salivary specimens (median OD/CO = 0.37) and 422 urinary specimens (median OD/CO = 0.39) collected from anti-HIV-negative individuals. These findings demonstrate that GACELISA HIV 1 + 2 tests on saliva or on urine are an accurate alternative to a conventional anti-HIV test of blood. This assay is satisfactory for surveillance purposes and, with appropriate precautions, could be used clinically.

Enzyme-Linked Immunosorbent Assay↗
PubMed1993

Anti-HIV testing by automated systems.

The accuracy and ease of use of three automated test systems (Behring Opus, Boehringer Mannheim ES300 and bioMerieux Vidas) and their associated assays (Opus HIV 1 + 2, Enzymun-Test Anti-HIV 1 + 2 and Vidas HIV 1 + 2) for the detection of anti HIV-1 and anti HIV-2 in human serum and plasma were investigated by testing them against a panel of 364 well-characterised specimens. The panel included specimens confirmed to contain anti HIV-1 (n = 65) and anti HIV-2 (n = 25), specimens collected during HIV-1 seroconversion (n = 40), specimens (n = 116) which had given spurious reactions in a variety of anti-HIV screening assays, specimens from patients infected with anti HTLV-I (n = 18) and specimens from unselected blood donors (n = 100). Excluding the seroconversion specimens, all three assays were 100% sensitive. Observed specificities ranged from 98.3% to 99.6%. For the seroconversion specimens the Vidas HIV 1 + 2 was the most sensitive overall. All three assays were as sensitive and specific as most of the conventional anti-HIV enzyme immunoassays currently available. The Opus and Vidas systems would be convenient for clinical laboratories handling small to medium numbers of specimens per day. The Boehringer Mannheim ES300 is designed for larger scale use and required more familiarisation.

Journal Article↗
PubMed1993

Avoiding false positive HIV results on life assurance proposers: the necessity for follow-up.

The serological reaction to HIV infection is almost invariably a dynamic progression towards strong reactivity to a wide range of viral antigens. Serological diagnosis should therefore be based either on the presence of this wide range in a single specimen or on the demonstration of increasing activity between two specimens collected at an interval of two or more weeks and tested in parallel. When a specimen is reactive a second should in any case be collected to check the identity of the first. These precepts are sometimes being ignored, especially in non-clinical testing, e.g., for purpose of life assurance. Two recent cases in which there were false but unchanging enzyme immunoassay and Western blot reactions that might have been interpreted as positive illustrate the potential for error.

Journal Article↗
PubMed1993

Are seroepidemiological surveys for human immunodeficiency virus infection based on tests on pools of serum specimens accurate and cost-effective?

Serum specimens (n = 17668) from UK antenatal patients in the Thames Regions were tested by Wellcozyme HIV 1/2 EIA singly and in pools of 6, 12 and 24: 35 (0.2%, 1 in 505) were confirmed as anti-HIV positive. The pools of 12 were also tested for anti-HIV 1/2 by IAF Biochem, Behring and Diagnostics Pasteur EIAs. All 35 positive specimens were easily detectable after pooling in groups of 12. The false positive rate for Wellcozyme was nearly halved compared with individual testing (1 in 309 false positive compared with 1 in 174). For the other assays false positive rates on pools of 12 were: IAF Biochem 1 in 193, Behring 1 in 140, Diagnostics Pasteur 1 in 1547. Twenty-two known anti-HIV 2-positive sera were detected by all four EIAs when diluted as in pools of 6 and 12, but by only three EIAs in pools of 24 and 48. Pooling in groups of 6 did not seem to delay detection of HIV 1 seroconversion, but pooling in groups of 12, 24 and 48 might delay it by 1, 2 and 3 weeks respectively. For this study the effect of pooling in groups of 12 would have been a reagent saving of 87-91% and a labour saving of about 50%. Because of the low HIV incidence and rarity of specimens collected around seroconversion in UK, little, if any, loss of sensitivity would result from it. Pooling in groups of 12 has therefore been chosen for the screening of anonymous antenatal specimens in the UK.

Journal Article↗
PubMed1993

Risk behaviour, anti-HIV and anti-hepatitis B core prevalence in clinic and non-clinic samples of gay men in England, 1991-1992.

OBJECTIVE: To describe the sexual risk behaviour of and HIV and hepatitis B antibody prevalence in gay men in England. DESIGN: Cross-sectional. RESPONDENTS: Gay men recruited from community settings (bars, clubs, gay organizations) and genito-urinary clinics in London, Manchester, the Midlands and Bristol; men who participated in an earlier study. METHODS: Interview including demographic information, sexual behaviour, partner type and health service use. Subjects donated saliva, which was screened for antibodies to HIV-1 by immunoglobulin G (IgG) antibody capture enzyme-linked immunosorbent assay (GACELISA) and to hepatitis B core (HBc) antigen by IgG antibody capture radioimmunoassay (GACRIA). RESULTS: Ninety-four out of 580 (16.2%) men were HIV-antibody-positive; 6.2% of men aged < or = 25 years were positive versus 19.5% of men aged > or = 26 years. HIV-antibody prevalence was highest in London (21.1%), and twice that previously reported outside London (10.5%). Ninety-four out of 568 (16.5%) men were HBc-antibody-positive; 6.9% of men aged < or = 25 years were positive versus 19.7% of men aged > or = 26 years. Anti-HBc prevalence was highest in London (19.8 versus 12.7% outside London). Manual workers were more likely to be anti-HBc-positive, as were men who reported recent high-risk intercourse. Sexually transmitted diseases associated with frequent partner change (gonorrhoea, non-specific urethritis) were reported. CONCLUSION: The HIV epidemic in gay men in England continues, particularly outside London, where prevalence was double that of previous studies. We found relatively high rates of infection in young men whose main sexual experience has been in a time of unprecedented awareness of AIDS. Our data on hepatitis B suggests that further pro-active immunization programmes are urgently required. These findings add to concerns about provision of interventions targeting gay men.

Adult↗
PubMed1993

HIV infection in injecting drug users attending centres in England and Wales, 1990-1991.

OBJECTIVE: To monitor trends in HIV infection and associated risk behaviours in injecting drug users (IDU) in England and Wales. DESIGN: Ongoing voluntary unlinked anonymous cross-sectional survey. METHOD: IDU attending centres in 1990 and 1991 were invited to complete a brief questionnaire requesting demographic and behavioural information, and to provide a saliva sample to be tested for antibodies to HIV and to the core antigen of hepatitis B virus (HBV). RESULTS: In 1990, 1.2% (19 out of 1543) of samples from 33 centres, and in 1991 1.8% (25 out of 1417) of samples from 37 centres contained antibody to HIV. Antibody t9 HBV core-antigen was found in 33 and 31% of IDU in 1990 and 1991, respectively. The prevalence of HIV infection in IDU attending centres in London (4.2%) was higher than in those attending centres elsewhere (0.8%). The prevalence of HIV infection in 1991 varied between individual centres from 0 to 10.6%, and at many centres outside London no IDU were infected with HIV. In the same year the prevalence of past infection with HBV varied from 14 to 54%, and IDU who had evidence of HBV infection were found among attenders in nearly all centres. The prevalences of sharing injecting equipment and risky sexual behaviour were high at many centres. The prevalence of HIV infection was higher in IDU who had started to inject in 1985 or earlier, than in those who started injecting later. In each year, approximately half the IDU surveyed reported having had a voluntary confidential HIV-antibody test, and the prevalence of HIV infection was five times higher in those tested than in those who had not been tested. CONCLUSIONS: HIV prevalence in IDU attending centres in England and Wales was low in 1990-1991. There is some indication that IDU have modified their injecting or sexual behaviour, but even at existing reduced levels of risk behaviour, transmission can occur in HIV is introduced into previously unexposed groups.

Adolescent↗