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D J Jeffries

Publications and source records attributed to D J Jeffries.

At least 19 recordsLinked to original sources
PubMed1991

Viral transmission and fibreoptic endoscopy.

Fibreoptic endoscopes have been responsible for outbreaks of infection with bacteria although viral transmission has been reported only once. The emergence of human immunodeficiency virus (HIV) has prompted a review of infection control practices in endoscopy units because of the theoretical possibility that HIV might be transmitted at endoscopy. Recent studies have shown that bronchoscopes and gastroscopes used on AIDS patients become contaminated with HIV genetic material although cleaning equipment in detergent removes all traces of the virus. Thorough precleaning has been shown to eliminate even high titres of HIV from endoscopes and 2% alkaline glutaraldehyde has been found to inactivate the virus rapidly even if the virus is dried in serum to a surface. These findings support the British Society of Gastroenterology recommendations for the cleaning and disinfection of endoscopic equipment and demonstrate that a uniform policy of infection control is practicable in endoscopy units.

DNA, Viral↗
PubMed1991

Recovery of the human immunodeficiency virus from fibreoptic bronchoscopes.

Ten bronchoscopes that had been used on patients with the acquired immunodeficiency syndrome were sampled to determine the nature and extent of microbial contamination. Samples were taken by irrigating the suction biopsy channel with modified viral transport medium and by swabbing the insertion tube. Sampling was repeated after they had been cleaned in detergent and after two minutes' disinfection in 2% alkaline glutaraldehyde. Before being cleaned the seven bronchoscopes tested by polymerase chain reaction were contaminated with the human immunodeficiency virus, though infectivity and antigen assays gave negative results. Other organisms identified were hepatitis B virus (1), commensal bacteria (9), and Pneumocystis carinii (4). Mean bacterial contamination was 2.27 log colony forming organisms per millilitre. Cleaning the bronchoscope before disinfection removed all detectable contaminants with a reduction in bacterial growth of up to 8 log colony forming units/ml.

Bronchoscopes↗
PubMed1991

Intra-uterine and neonatal herpes simplex virus infection.

Herpes simplex viruses type 1 (buccal) and type 2 (genital) present a serious threat to neonates. Infection may occur in utero, by transplacental or ascending infection, by exposure to genital lesions during delivery, or postnatally from relatives or attendants. Antiviral drugs, vidarabine and acyclovir are of equal efficacy and toxicity when used in infants with herpes simplex infections. Transplacental infection during early pregnancy is a very rare cause of congenital abnormality but there have been no recommendations for intervention. Most neonatal infections are acquired from the mother during delivery. Antepartum screening for virus excretion is of no value in predicting exposure at delivery and should not be performed. Caesarean section should be reserved for women who have active lesions at delivery. Even if active lesions are present, in women with a history of recurrent herpes, the risks to the infant are low. Prophylactic acyclovir during pregnancy cannot be recommended until evidence of safety and efficacy has been obtained from controlled trials. Staff should be alert to the dangers of postnatal infection and measures should be taken to exclude, or reduce virus excretion from, staff members or visitors who have orolabial or cutaneous herpes lesions.

Female↗
PubMed1990

HIV and AIDS.

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Acquired Immunodeficiency Syndrome↗
PubMed1990

Synthesis and anti-HIV evaluation of some phosphoramidate derivatives of AZT: studies on the effect of chain elongation on biological activity.

A series of phosphoramidate derivatives of the anti-HIV drug AZT has been prepared as membrane soluble pro-drugs of the bio-active nucleotide forms and evaluated in vitro against HIV-1. Terminal substituted alkyl amines have a pronounced anti-HIV effect: this effect declines upon increasing the length of the methylene spacer. The results are consistent with a mechanism of action involving intracellular cleavage of the phosphoramidate bond, and release of the nucleotide, or a derivative thereof. Full spectroscopic data are included on the products and their phosphorochloridate precursors.

Cells, Cultured↗
PubMed1990

Detection of HIV-1 in human lung macrophages using the polymerase chain reaction.

We have used the polymerase chain reaction to investigate HIV-1 infection of lung macrophages from 44 AIDS patients with pneumonia. Proviral HIV-1 DNA was detected in the lung macrophages of 47% (21 of 44) of patients tested; 32% (seven of 21) of the patients had Pneumocystis carinii pneumonia (PCP), and 56% (11 of 21) had pneumonia caused by other aetiological agents. Matched peripheral blood specimens were obtained from 22 patients in this study, and HIV-1-specific DNA was detected in 100% (22 out of 22) of non-adherent white cell preparations tested. HIV was detected in blood monocytes of 11 out of 22 patients (50%), and a virus signal was also found in the lung macrophages of eight of these patients. Our results indicate that PCP does not predispose lung macrophages to HIV-1, nor does HIV-1 infection of lung macrophages increase the probability of contracting PCP.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Elimination of high titre HIV from fibreoptic endoscopes.

Concern about contamination of fibreoptic endoscopes with human immunodeficiency virus (HIV) has generated a variety of disruptive and possibly unnecessary infection control practices in endoscopy units. Current recommendations on the cleaning and disinfection of endoscopes have been formulated without applied experimental evidence of the effective removal of HIV from endoscopes. To study the kinetics of elimination of HIV from endoscope surfaces, we artificially contaminated the suction-biopsy channels of five Olympus GIF XQ20 endoscopes with high titre HIV in serum. The air and water channels of two instruments were similarly contaminated. Contamination was measured by irrigating channels with viral culture medium and collecting 3 ml at the distal end for antigen immunoassay. Endoscopes were then cleaned manually in neutral detergent according to the manufacturer's recommendations and disinfected in 2% alkaline glutaraldehyde (Cidex, Surgikos) for two, four, and ten minutes. Contamination with HIV antigens was measured before and after cleaning and after each period of disinfection. Initial contamination comprised 4.8 x 10(4) to 3.5 x 10(6) pg HIV antigen/ml. Cleaning in detergent achieved a reduction to 165 pg/ml (99.93%) on one endoscope and to undetectable levels (100%) on four. After two minutes in alkaline glutaraldehyde all samples were negative and remained negative after the longer disinfection times. Air and water channels, where contaminated, were tested after 10 minutes' disinfection and were negative. These findings underline the importance of cleaning in removing HIV from endoscope and indicate that the use of dedicated equipment and long disinfection times are unnecessary.

Acquired Immunodeficiency Syndrome↗
PubMed1990

An update on HIV-testing at a London sexually transmitted diseases clinic: long-term impact of the AIDS media campaigns.

Trends in the number of tests for HIV-1 antibody at a London sexually transmitted diseases clinic showed substantial changes between September 1985 and June 1988. From an average of 100 tests per month between September 1985 and August 1986, the average increased to 365 tests per month for September 1986 to August 1987. This levelled off at 243 tests per month between September 1987 and June 1988. The average number of positive tests per month between September 1985 and June 1988 remained constant, though the number of seropositive tests in females increased. Male and female populations displayed similar temporal patterns. The greatest increase was seen in the tests generated by heterosexual males and females with no other risk factors. This group generated 42% of the 8012 tests performed during the study period. The Clinic's catchment area predominantly included London and surrounding areas and temporal patterns were similar for residents from each of the Thames Regions. The temporal patterns observed coincided with periods of increased media attention on HIV infection/AIDS and involved campaigns by the popular press, television, Department of Health Education Authority. The increase in tests during the time of maximum media exposure, the subsequent plateau at a level substantially higher compared with the period preceding the media campaigns and the large increase in heterosexual males and females tested, all suggest that the campaigns have contributed to increasing awareness of HIV infection/AIDS as a major contemporary public health problem.

AIDS Serodiagnosis↗