Gerald Corbitt

Low HIV and high STD among commercial sex workers in a brothel in Bangladesh : scope for prevention of larger epidemic

Summary: The present study documents the first systematic assessment of a brothel in Bangladesh in terms of sexually transmitted disease (STD) and human immunodeficiency virus (HIV). A cross sectional study was undertaken on brothel-based commercial sex workers (CSWs) selected systematic random sampling to assess the prevalence of STDs and HIV among CSWs in a brothel setting. Two hundred and ninety-six CSWs were selected from a brothel with a population of 593 women. Following informed consent, endocervical and blood samples were obtained for the diagnosis of genital chlamydia, gonorrhoea, HIV and syphilis respectively. In addition, another 170 consecutive blood samples were collected from the total CSW population for HIV tests. All blood samples for HIV testing were made anonymous by removing patient identifiers before testing. Endocervical specimens were tested by polymerase chain reaction (PCR) for the diagnosis of genital chlamydia and gonorrhoea. Syphilis and HIV infections were diagnosed by serology. One hundred and sixty-nine (57.1%) of the women were Treponema pallidum haemagglutination (TPHA)-positive, 20 (6.8%) of the women were Venereal Disease Research Laboratory (VDRL)-positive at a greater than 1:8 dilution. Eighty-two (28%) of the women were found to be infected either by gonorrhoea or chlamydia. No HIV antibody was found in any of the 466 blood samples. A high prevalence of STDs and low prevalence of HIV in the CSWs in Bangladesh suggest potential for the rapid spread of HIV once it is introduced in this high-risk population. The opportunity to control STD and HIV infection in this population should not be missed, in order to prevent a large epidemic in the future.

Detection of male genital infection with Chlamydia trachomatis and Neisseria gonorrhoeae using an automated multiplex PCR system (Cobas Amplicor).

Summary: We evaluated Cobas AmplicorTM, a highly automated polymerase chain reaction (PCR) system, to test first-void urine (FVU) and urethral swab specimens for Chlamydia trachomatis and Neisseria gonorrhoeae in men attending a sexually transmitted infection (STI) clinic. Results were compared against an inhouse radioimmune dot blot (DB) test for C. trachomatis and selective culture for N. gonorrhoeae . Three hundred and ninety sets of specimens were obtained from 378 consecutive new and returned-new patients. Gonorrhoea prevalence was 9.49%, with no significant difference in sensitivity or specificity between culture and PCR. Chlamydia prevalence was 15.4%, with sensitivities of: DB 55%, PCR of FVU 86.7%, urethral swab PCR 90%. The specificity of PCR on FVU and urethral swabs was 100%. We have shown that Cobas AmplicorTM PCR is highly sensitive and specific in the diagnosis of chlamydia and gonorrhoea in men attending an STI clinic. Further economic and scientific studies are needed to determine the costeffectiveness of this technique for screening in primary care settings.

Fatal disseminated adenovirus type 2 infection following bone marrow transplantation for Hurler's syndrome: A primary infection

A 5-month-old girl given an allogeneic bone marrow transplant for Hurlers syndrome succumbed to fatal pneumonia 5 weeks after the transplant. Adenovirus type 2 was isolated from her urine before she died. Immunoperoxidase and electron microscopical studies of liver and lungs post mortem confirmed a disseminated adenovirus infection. The serological findings and the patients young age suggested that the infection was a primary one. The importance of considering exogenous sources of adenovirus infection in bone marrow transplant recipients is discussed.

Detection of hepatitis C virus RNA in serum, by combining reverse transcription and polymerase chain reaction in one tube.

Reverse transcription of viral RNA into cDNA and its subsequent amplification by polymerase chain reaction (PCR) are generally carried out as two separate reactions. Here we describe a novel method for the detection of HCV RNA in serum combining both steps in one reaction tube using a wax interface to separate the two sets of reactants during initial cDNA synthesis. This enabled optimisation of both reactions, simplified the test and thereby reduced the risk of cross-contamination.

Computer network for a diagnostic virology laboratory.

Abstract A data base for a large diagnostic virology laboratory is described. The system uses a network of personal computers. It allows the entry, long-term storage, and subsequent retrieval of specimen and patient records (comprising personal identifiers and specimen and result information), and hard-copy results reporting. Sited entirely within the laboratory, the network is not connected to a modem. Within the laboratory there is restricted access to human immunodeficiency virus test results to guarantee patient confidentiality. Retention of a hard-copy of specimen request cards ensures the availability of the original clinical information. The data base is copied on a second file server to facilitate searches, and daily streaming onto magnetic tape provides system protection in the event of hard disc failure. Matching of old and new patient records is done by surname, date of birth, and sex, and therefore duplicate records accumulate when patient names are misspelt on specimen request forms. The system requires further development to speed searches of the data base and to achieve automatic generation of laboratory worksheets. Future goals are the replacement of hard-copy records of clinical information and hard-copy reporting with on-line access to hospital data bases and on-line requesting by and reporting to the clinician.

EFFECT OF SWITCHING FROM FIRST- TO SECOND-GENERATION ENZYME-LINKED IMMUNOSORBENT ASSAYS ON SCREENING FOR HUMAN IMMUNODEFICIENCY VIRUS ANTIBODY

Abstract When a commercial antiglobulin or competitive enzyme-linked immunosorbent assay (ELISA) was used for initial human immunodeficiency virus (HIV) antibody screening, switching from a first-generation test (antigen prepared from HIV-infected human cells) to a second-generation test (antigen prepared by recombinant DNA technology) reduced but did not abolish false-positive reactivity. This conclusion applied if specimens were obtained either from a low (attenders at a voluntary walk-in clinic) or very-low prevalence population (attenders at an in-vitro fertilisation unit). Even when the specimen was reactive in second-generation screening ELISAs of both antiglobulin or competitive format, confirmatory testing was still essential. Same-day reporting of HIV antibody test results should therefore only be done circumspectly.

Prolonged excretion of herpesvirus varicellae in a child with acute lymphoblastic leukaemia

An eight-year-old girl with acute lymphoblastic leukaemia (ALL) in remission presented with varicella. Zoster immune globulin was not given, but treatment with acyclovir was commenced the day after presentation and continued for five days. Many of the original vesicles ulcerated and persisted for periods in excess of three months, finally leaving residual scarring. Further new vesicles appeared at 80 days and 109 days, and virus was again visualised by electron microscopy. Seroconversion was not demonstrated, although the child has in the past responded serologically to other viruses. A series of other infections afflicting the child at about the same time is documented and the possible implications are discussed.