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Biomedical subjects

G Rutherford

Publications and source records attributed to G Rutherford.

18 recordsLinked to original sources
PubMed2004

Population-based interventions for reducing sexually transmitted infections, including HIV infection.

BACKGROUND: Sexually transmitted infections (STI) are common in developing countries. The World Health Organisation (WHO) estimates that in 1999, 340 million new cases of syphilis, gonorrhoea, chlamydial infection and trichomoniasis occurred. Human immunodeficiency virus (HIV) infection is also common in developing countries. UNAIDS estimates that over 95% of the 40 million people infected with HIV by December 1999 live in developing countries (UNAIDS 2003). The STI and HIV epidemics are interdependent. Similar behaviours, such as frequent unprotected intercourse with different partners, place people at high risk of both infections, and there is clear evidence that conventional STIs increase the likelihood of HIV transmission. Several studies have demonstrated a strong association between both ulcerative and non-ulcerative STIs and HIV infection (Cameron 1989, Laga 1993). There is biological evidence, too, that the presence of an STI increases shedding of HIV, and that STI treatment reduces HIV shedding (Cohen 1997, Robinson 1997). Therefore, STI control may have the potential to contribute substantially to HIV prevention. OBJECTIVES: To determine the impact of population-based STI interventions on the frequency of HIV infection, frequency of STIs and quality of STI management. SEARCH STRATEGY: The following electronic databases were searched for relevant randomised trials or reviews:1) MEDLINE for the years 1966 to 2003 using the search terms "sexually transmitted diseases" and "human immunodeficiency virus infection"2) The Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effectiveness and the Cochrane Clinical Trials Register, in the most recent issue of the Cochrane Library3) The specialist registry of trials maintained by the Cochrane Infectious Diseases Group.4) EMBASE The abstracts of relevant conferences were searched, and reference lists of all review articles and primary studies were scanned. Finally, authors of included trials and other experts in the field were contacted as appropriate. SELECTION CRITERIA: Randomised controlled trials in which the unit of randomisation is either a community or a treatment facility. Studies where individuals are randomised were excluded. DATA COLLECTION AND ANALYSIS: Two reviewers independently applied the inclusion criteria to potential studies, with any disagreements resolved by discussion. Trials were examined for completeness of reporting. The methodological quality of each trial was assessed by the same two reviewers, with details recorded of randomisation method, blinding, use of intention-to-treat analysis and the number of patients lost to follow-up, using standard guidelines of the Cochrane Infectious Diseases Group. MAIN RESULTS: Five trials were included. Frequency of HIV infection: In Rakai, after 3 rounds of treatment of all community members for STIs, the rate ratio of incident HIV infection was 0.97 (95%CI 0.81 to 1.16), indicating no effect of the intervention. In Mwanza, the incidence of HIV infection in the intervention groups (strengthened syndromic management of STIs in primary care clinics) was 1.2% compared with 1.9% in the control groups (OR=0.58, 95% CI 0.42-0.70), corresponding to a 38% reduction (95%CI 15% to 55%) in HIV incidence in the intervention group. In the newest trial by Kamali et al, the rate ratio of behavioral intervention & STI management compared to control on HIV incidence was 1.00 (0.63-1.58, p=.98). These are consistent with Rakai data showing no effect of intervention. Frequency of STIs: In both Mwanza and Rakai, there was no significant reduction in gonorrhoea, chlamydia, urethritis, or reported STI symptoms among intervention communities. The prevalence ratio of syphilis between intervention and control groups in Rakai was 0.8 (95%CI 0.71-0.89), of trichmoniasis was 0.59 (0.38-0.91), and of bacterial vaginosis was 0.87 (0.74-1.02). In Mwanza, the prevalence of serologically diagnosed syphilis in the intervention community was 5% compared with 7% in the control community at the end of the trial (adjusted re7% in the control community at the end of the trial (adjusted relative risk 0.71 (95%CI 0.54-0.93). In Kamali et al, there was a significant decrease in gonorrhoea and active syphilis cases. Rate ratio for gonorrhoea was 0.29(0.12-0.71, p=0.016), active syphilis was 0.53(0.33-0.84,p=0.016). There was a trend towards significance with intervention on the use of condoms with the last casual partner; the rate ratio was 1.27(1.02-1.56,p=0.036). Quality of treatment: In Lima, following training of pharmacy assistants in STI syndromic management, symptoms were recognised as being due to an STI in 65% of standardised simulated patients (SSPs) visiting intervention and 60% of SSPs visiting control pharmacies (p=0.35). Medication was offered without referral to a doctor in most cases (83% intervention and 78% control, p=0.61). Of those SSPs offered medication, only 1.4% that visited intervention pharmacies and only 0.7% of those that visited control pharmacies (p=0.57) were offered a recommended regimen. Similarly in only 15% and 16% of SSP visits respectively was any recommended drug offered. However, education and counseling were more likely to be given to SSPs visiting intervention pharmacies (40% vs 27%, p=0.01). No SSPs were given partner cards or condoms. In Hlabisa, following the intervention targeting primary care clinic nurses (strengthened STI syndromic management and provision of STI syndrome packets containing recommended drugs, condom, partner cards and patient information leaflets), SSPs were more likely to be given recommended drugs in intervention clinics (83% vs 12%, p<0.005) and more likely to be correctly case managed [given correct drugs, partner cards and condoms] (88% vs 50%, p<0.005). There were no significant differences in the proportions adequately counseled (68% vs 46%, p=0.06), experiencing good staff attitude (84% vs 58%, p=0.07), and being consulted in privacy (92% vs 86%, p=0.4). There was no strong evidence of any impact on treatment-seeking behaviour, utilisation of services, or sexual behaviour in any of the four trials. REVIEWERS' CONCLUSIONS: There is limited evidence from randomised controlled trials for STI control as an effective HIV prevention strategy. Improved STI treatment services have been shown to reduce HIV incidence in an environment characterised by an emerging HIV epidemic (low and slowly rising prevalence), where STI treatment services are poor and where STIs are highly prevalent. There is no evidence for substantial benefit from treatment of all community members. The addition of the Kamali trial to the existing evidence supports the data from the Rakai trial of no effect. There are, however, other compelling reasons why STI treatment services should be strengthened, and the available evidence suggests that when an intervention is accepted it can substantially improve quality of services provided. The Kamali trial shows an increase in the use of condoms, a marker for improved risk behaviors. Further community-based randomised controlled trials that test a range of alternative STI control strategies are needed in a variety of different settings. Such trials should aim to measure a range of factors that include health seeking behaviour and quality of treatment, as well as HIV, STI and other biological endpoints.

Developing Countries↗
PubMed2002

Nonoxynol-9 for preventing vaginal acquisition of HIV infection by women from men.

BACKGROUND: There is a need for female-controlled methods of HIV prevention. Vaginal microbicides, substances inserted into the vagina to prevent women acquiring HIV and sexually transmitted infections (STIs) from men, could be useful in this regard. One potential vaginal microbicide is the widely used spermicide, nonoxynol-9 (N-9). OBJECTIVES: To determine the safety and effectiveness of N-9 in preventing vaginal acquisition of HIV infection by women from men. SEARCH STRATEGY: Extensive searches of electronic databases, conference abstracts, reference lists of relevant studies and contact with experts and funders. SELECTION CRITERIA: Randomised controlled trials meeting pre-determined quality criteria with HIV infection as the outcome. DATA COLLECTION AND ANALYSIS: Data were extracted by one reviewer and checked by the another. Any discrepancies were adjudicated by a third reviewer. MAIN RESULTS: Five trials were included in the review and four contributed to a meta-analysis. Overall, the risk of HIV infection was not statistically significantly different among women receiving N-9 (relative risk [RR] 1.12, 95% CI 0.88-1.42; p=0.4). The risk of genital lesions was statistically significantly greater among women receiving N-9 (RR 1.18, 95%CI 1.02-1.36; p=0.02). REVIEWER'S CONCLUSIONS: There is no evidence that nonoxynol-9 protects against vaginal acquisition of HIV infection by women from men. There is evidence that it may do harm by increasing the frequency of genital lesions.

Coitus↗
PubMed2002

Nonoxynol-9 for preventing vaginal acquisition of sexually transmitted infections by women from men.

BACKGROUND: The incidence and prevalence of sexually transmitted infections (STI) and other reproductive tract infections (RTI) is high in much of the developing and parts of the developed worlds. STIs and RTIs are associated with the vaginal transmission of HIV. Additional strategies to improve STI control are needed, and vaginal microbicides are a possible strategy. One potential vaginal microbicide is the widely used spermicide, nonoxynol-9 (N-9). OBJECTIVES: To determine the safety and effectiveness of N-9 in preventing vaginal acquisition of sexual transmitted infections (exclusive of HIV) by women from men. SEARCH STRATEGY: Systematic search of electronic databases, conference abstracts, reference lists of relevant studies and contact with experts and funders. SELECTION CRITERIA: Randomised controlled trials meeting pre-determined quality criteria with STI as the outcome. DATA COLLECTION AND ANALYSIS: Data were extracted by one reviewer and checked by another. MAIN RESULTS: Ten of 12 identified randomised controlled trials were included and findings among them were broadly consistent. In meta-analysis, the risks of gonorrhoea (relative risk [RR] 0.91, 95%CI 0.67-1.24), cervical infection (RR 1.01, 0.84-1.22), trichomoniasis (RR 0.84, 0.69-1.02), bacterial vaginosis (0.88, 0.74-1.04), chlamydia (RR 0.88, 0.77-1.01) and candidiasis (RR 0.97, 0.84-1.12) were not statistically significantly different in women receiving N-9 compared with placebo. Genital lesions were more common in the N-9 users (RR 1.17, 95%CI 1.02-1.35). REVIEWER'S CONCLUSIONS: There is good evidence that nonoxynol-9 does not protect against sexually transmitted infections, and there is some evidence that it may be harmful by increasing the rate of genital ulceration. As such, this product cannot be recommended for STI prevention.

Female↗
PubMed2001

Population-based interventions for reducing sexually transmitted infections, including HIV infection.

BACKGROUND: Sexually transmitted infections (STI) are common in developing countries. The World Health Organisation (WHO) estimates that in 1995, 333 million new cases of syphilis, gonorrhoea, chlamydial infection and trichomoniasis occurred. Human immunodeficiency virus (HIV) infection is also common in developing countries. UNAIDS estimates that over 90% of the 33 million people infected with HIV by December 1999 live in developing countries (UNAIDS 1999). The STI and HIV epidemics are interdependent. Similar behaviours, such as frequent unprotected intercourse with different partners, place people at high risk of both infections, and there is clear evidence that conventional STIs increase the likelihood of HIV transmission. Several studies have demonstrated a strong association between both ulcerative and non-ulcerative STIs, and HIV infection (Cameron 1989, Laga 1993) and there is biological evidence that the presence of an STI increases shedding of HIV and that STI treatment reduces HIV shedding (Cohen 1997, Robinson 1997). Therefore, STI control may have the potential to contribute substantially to HIV prevention. OBJECTIVES: To determine the impact of population-based STI interventions on the frequency of HIV infection, frequency of STIs and quality of STI management. SEARCH STRATEGY: The following electronic databases were searched for relevant randomised trials or reviews: 1) MEDLINE for the years 1966 to current using the search terms sexually transmitted diseases and human immunodeficiency virus infection 2) The Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effectiveness and the Cochrane Clinical Trials Register in the most recent issue of the Cochrane Library 3) The specialist register of trials maintained by the Cochrane Infectious Diseases Group. 4) EMBASE The abstracts of relevant conferences were searched and reference lists of all review articles and primary studies were scanned. Finally, authors of included trials and other experts in the field were contacted as appropriate. SELECTION CRITERIA: Randomised controlled trials in which the unit of randomisation is either a community or a treatment facility. Studies where individuals are randomised were excluded. DATA COLLECTION AND ANALYSIS: Two reviewers independently applied the inclusion criteria to potential studies with any disagreements resolved by discussion. Trials were examined for completeness of reporting. The methodological quality of each trial was assessed by the same two reviewers with details recorded of randomisation method, blinding, use of intention-to-treat analysis and the number of patients lost to follow-up using standard guidelines of the Cochrane Infectious Diseases Group. MAIN RESULTS: Four trials were included. Frequency of HIV infection: In Rakai, after 3 rounds of treatment of all community members for STIs the rate ratio of incident HIV infection was 0.97 (95%CI 0.81 to 1.16), indicating no effect of the intervention. In Mwanza, the incidence of HIV infection in the intervention groups (strengthened syndromic management of STIs in primary care clinics) was 1.2% compared with 1.9% in the control groups (OR=0.58, 95% CI 0.42-0.70), corresponding to a 38% reduction (95%CI 15% to 55%) in HIV incidence in the intervention group. Frequency of STIs: In both Mwanza and Rakai, there was no significant reduction in gonorrhoea, chlamydia, urethritis, or reported STI symptoms among intervention communities. The prevalence ratio of syphilis between intervention and control groups in Rakai was 0.8 (95%CI 0.71-0.89), of trichmoniasis was 0.59 (0.38-0.91), and of bacterial vaginosis was 0.87 (0.74-1.02). In Mwanza, the prevalence of serologically diagnosed syphilis in the intervention community was 5% compared with 7% in the control community at the end of the trial (adjusted relative risk 0.71 (95%CI 0.54-0.93). Quality of treatment: In Lima, following training of pharmacy assistants in STI syndromic management, symptoms were recognised as being due to an STI in 65% of standardised simulated patients (SSPs) visiting intervention and 60% of SSPs visiting control pharmacies (p=0.35). Medication was offered without referral to a doctor in most cases (83% intervention and 78% control, p=0.61). Of those SSPs offered medication, only 1.4% that visited intervention pharmacies and only 0.7% of those that visited control pharmacies (p=0.57) were offered a recommended regimen. Similarly in only 15% and 16% of SSP visits respectively was any recommended drug offered. However, education and counseling were more likely to be given to SSPs visiting intervention pharmacies (40% vs 27%, p=0.01). No SSPs were given partner cards or condoms. In Hlabisa, following the intervention targeting primary care clinic nurses (strengthened STI syndromic management and provision of STI syndrome packets containing recommended drugs, condom, partner cards and patient information leaflets), SSPs were more likely to be given recommended drugs in intervention clinics (83% vs 12%, p <0.005) and more likely to be correctly case managed [given correct drugs, partner cards and condoms] (88% vs 50%, p <0.005). There were no significant difference in the proportions adequately counseled (68% vs 46%, p=0.06), experiencing good staff attitude (84% vs 58%, p=0.07), and being consulted in privacy (92% vs 86%, p=0.4). There was no strong evidence of any impact on treatment seeking behaviour, utilisation of services, or sexual behaviour in any of the four trials. REVIEWERS' CONCLUSIONS: There is limited evidence from randomised controlled trials for STI control as an effective HIV prevention strategy. Improved STI treatment services have been shown to reduce HIV incidence in an environment characterised by an emerging HIV epidemic (low and slowly rising prevalence), where STI treatment services are poor and where STIs are highly prevalent. There is no evidence for substantial benefit from treatment of all community members. There are however other compelling reasons why STI treatment services should be strengthened and the available evidence suggests that when an intervention is accepted it can substantially improve quality of services provided. Further community based randomised controlled trials that test a range of alternative STI control strategies are needed in a variety of different settings. Such trials should aim to measure a range of factors that include health seeking behaviour and quality of treatment as well as HIV, STI and other biological endpoints.

Developing Countries↗
PubMed1997

Truck drivers in Brazil: prevalence of HIV and other sexually transmitted diseases, risk behavior and potential for spread of infection.

OBJECTIVES: To determine the prevalence of HIV and syphilis and related risk behavior in a sample of truck drivers in Santos, Brazil. SUBJECTS AND METHODS: A cross-sectional study was performed of 300 male truck drivers recruited in the port of Santos, Brazil, including a face-to-face interview and blood sampling for HIV and syphilis serology. RESULTS: Of 300 subjects, 4 (1.3%) were positive for HIV, 25 (8.3%) for syphilis by the Venereal Disease Research Laboratory (VDRL) test and 38 (13%) were positive for syphilis by the fluorescent treponemal antibody (absorbed) test (FTA-Abs). Seventy-one per cent had been employed as truck drivers for more than 10 years and 93% lived outside of Santos. Most participants were married (72%); 40% reported having more than one sex partner; 21% reported sex with commercial sex workers; 14% reported sex with girls that they met on the road; 16% had sex with other men's wives; and 3.3% reported sex with men during the past year. The use of rebite, an oral stimulant, was reported by 43% and was associated with being FTA-Abs-positive (P = 0.04). Being HIV-positive was associated with having sex with friends (P = 0.04), partners usually considered 'safe' by truck drivers. Being syphilis-positive (VDRL) was significantly associated with sex with partners also considered as 'safe', namely primary sex partners, steady partners and other men's wives. DISCUSSION: This is the first study to determine HIV and syphilis seroprevalence among truck drivers in South America. Findings confirm that this group has a high potential risk for HIV infection and other sexually transmitted diseases, and thus currently presents an opportunity for prevention.

Adult↗
PubMed1993

Helping people help themselves.

With the growing consumer participation movement and the emphasis in health care shifting from hospital to community, the term community development is cropping up more and more. Yet the concept of community development has always been integral to public health nursing. Simply put, community development is a process by which a community identifies its needs and assumes ownership of decision-making and subsequent action surrounding those needs. By integrating community development principles into their work with two neighboring communities, nurses with Calgary Health Services facilitated the establishment of a much-needed parent support group.

Community Participation↗
PubMed1992

Determinants of survival in adult Brazilian AIDS patients, 1982-1989. The Brazilian State AIDS Program Co-Ordinators.

OBJECTIVE: Little has been published about the length and determinants of survival for persons with AIDS in developing countries. This study examined the survival experience of Brazilian AIDS patients from 1982 to 1989. DESIGN: A retrospective cohort study involving record review of reported AIDS cases. METHODS: We obtained information about 2135 adult AIDS patients in Brazil. Local health officials supplied data regarding demographic and clinical characteristics and length of survival. Statistical techniques of survival analysis were applied. RESULTS: Median survival was 5.1 months, much shorter than in developed countries, and there was no improvement in survival for cases diagnosed more recently. Younger patients and those in the intravenous drug use exposure category lived longer than other AIDS patients. Those presenting with Kaposi's sarcoma, esophageal candidiasis, and tuberculosis fared relatively well, while those presenting with multiple diagnoses or toxoplasmosis did more poorly. CONCLUSIONS: These results tend to confirm the predictors of AIDS survival previously reported from developed countries and to document the poor survival of AIDS patients in the developing world.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Progressive multifocal leukoencephalopathy in persons infected with human immunodeficiency virus, San Francisco, 1981-1989.

Progressive multifocal leukoencephalopathy (PML), a rare neurological disease, has been sporadically reported in persons infected with human immunodeficiency virus (HIV), the causative agent of acquired immune deficiency syndrome (AIDS). From January 1981 through February 1989, in San Francisco, we identified 94 HIV-infected persons with PML, of whom 48 (51%) were pathologically confirmed (as required for AIDS case reporting). These 48 patients were significantly older when diagnosed with AIDS (20% older than 50 years) than patients with AIDS without PML. The remaining 46 (49%) patients, diagnosed clinically and by neuroimaging, did not differ significantly from definitive patients in demographic or survival characteristics after PML diagnosis. We detected antibodies to JC virus, the causative agent of PML, in 9 of 14 (64%) AIDS-related patients with PML, and in 9 of 14 (64%) matched control subjects, suggesting that determination of JC virus antibody status before AIDS diagnosis does not reliably indicate which patients will contract PML. Our study shows that the proportion of patients with AIDS who contracted PML remained stable between 1981 and 1988, but increased in the first 2 months of 1989. Our findings further indicate that PML in HIV-infected patients may be underestimated by as much as 50%.

Adolescent↗
PubMed1989

Essential large transcripts of the maize Spm transposable element are generated by alternative splicing.

We used in vitro mutagenesis and cDNA cloning to identify new Suppressor-mutator (Spm) transposable element genes. Frameshift mutations in the ORFs of the tnpA gene's first intron markedly reduce Spm activity in transgenic tobacco, indicating that intron sequences encode essential gene products. Evidence is given that Spm encodes large alternatively spliced transcripts, designated tnpB (4.9 kb), tnpC (5.7 kb), and tnpD (5.8 kb), comprising all of the tnpA exons, most of the tnpA intron 1 ORF1 sequence, and either none, part, or all of the intron 1 ORF2 sequence. Two alternative splice donor sites were identified at the end of exon 1, and the structure of the different exon 1 sequences suggests that Spm employs a novel mode of translational regulation.

DNA↗
PubMed1988

Estimating AIDS infection rates in the San Francisco cohort.

Between 1978 and 1980 a cohort of approximately 6700 homosexual and bisexual men were recruited from the San Francisco City Clinic to participate in studies of sexually transmitted hepatitis B. Testing frozen blood specimens collected at intervals from these patients provides a means of tracking the spread of the AIDS virus since 1978. The rate of spread of HIV was estimated by fitting different survival curves to interval-censored serological data using maximum likelihood techniques. The curves were compared using the Akaike Information Criterion (AIC) to select that which best describes the data. The best was found to be a log-logistic model, which suggested that between 1978 and 1981 the virus spread rapidly, infecting 44% of the then uninfected cohort members. More recently the rate of spread has declined, with an additional 32% of the cohort becoming infected between 1981 and 1987.

Acquired Immunodeficiency Syndrome↗
PubMed1984

Outbreak of paralytic poliomyelitis, Taiwan.

Taiwan had been free of major poliomyelitis outbreaks since 1975, but from May 29 to Oct 26, 1982, 1031 cases of type 1 paralytic poliomyelitis were reported to the Taiwan health authorities. Before the outbreak approximately 80% of infants had received at least 2 doses of trivalent oral poliovaccine (OPV) by their first birthday. Of the 86% of poliomyelitis patients whose vaccination status was known 65% had not had poliovaccine, 19% had received one dose, 8% had received two doses, and 8% had received three or more doses. Vaccine efficacy was calculated to be 82% after one dose, 96% after two doses, and 98% after three or more doses. Failure to vaccinate rather than vaccine failure was the most important risk factor in this outbreak. A child who had not had any vaccine was 80 times more likely to become a case than one who had received three or more doses of poliovaccine, independent of sanitation facilities at home. A child was 5 times more likely to become a case if he received water from non-municipal rather than municipal sources. Furthermore, for children who received municipal water, the risk was doubled if the family shared a toilet with at least one other family. This outbreak shows that major epidemics can occur in areas that have high overall community vaccination levels. Identification and vaccination of subpopulations with low coverage is essential for the control of poliomyelitis.

Adolescent↗
PubMed1968

Control of tantrum behavior by operant techniques during experimental verbal training.

A technique of controlling undesirable or disruptive behavior during an ongoing program of verbal training with a retardate is described. The technique required that the stimulus materials of the verbal training program be graded according to difficulty, i.e., in terms of the length and complexity of the stimulus materials. (This resulted in an initial grading of the stimulus materials into different levels of probability of reinforcement.) Changes by the experimenter from high-difficulty to low-difficulty stimuli for two trials contingent upon disruptive behavior increased the rate of that behavior; changes from low-difficulty to high-difficulty stimuli for two trials contingent upon disruptive behavior decreased its rate. Thus, contingent alternation of the stimulus materials of the ongoing training program controlled the frequency of undesirable behaviors within the experimental sessions. This technique may comprise an alternative to other procedures which require punishment or timeout from the ongoing program.

Journal Article↗
PubMed1968

An experimental analysis of linguistic development: the productive use of the plural morpheme.

Operant conditioning procedures were used to establish a generative use of the plural morpheme in the speech of a severely retarded girl. During training trials, reinforcement was presented contingent upon correct imitation of singular and plural verbalizations by the experimenter, in response to objects presented to the subject singly and in pairs. A generative productive plural usage resulted, the girl correctly labeling new objects in the singular or plural without further direct training relevant to those objects. After establishing the singular/plural usage, the contingencies were reversed (reinforcement of plural responses to single objects, and vice-versa). This produced a corresponding reversal of response by the child. The original usage was then recovered by returning to the previous contingencies. A second experiment analyzed certain error responses occurring during the first experiment, and further probed the generative nature of the subject's plural usage. It was found that errors were somewhat more likely to occur in the pluralization of words ending in vowels than of words ending in consonants. Furthermore, several words whose plurals had been learned according to the reversed plural rule, when examined later during reinforcement of normal plural usage, were found then to exemplify the normal rule being reinforced, yet without direct training.

Journal Article↗
PubMedDate not supplied

Identification of HIV-infected transfusion recipients: the utility of crossreferencing previous donor records with AIDS case reports.

An expanded "look-back" program has been developed, in which patients who may have been exposed to HIV through blood transfusion were identified via three triggers: the blood that they received was donated by persons who 1) have subsequently been reported to local health departments as meeting the diagnostic criteria for AIDS, 2) have donated since the introduction of anti-HIV screening and tested positive, or 3) have been found to be infected during investigation of reported transfusion-associated HIV infections. In comparing triggers, cross-referencing the list of patients reported to have AIDS (AIDS case list) proved to be the most efficient approach for identifying HIV-infected donors and transfusion recipients. Of the 7973 AIDS patients reported in eight Northern California counties as of December 1988, 316 (4.0%) were determined to have donated at Irwin Memorial Blood Centers between 1977 and 1985. Despite the logarithmic increase in reported cases of AIDS in the San Francisco Bay area over the last 5 years, the rate of detection of previous donors from AIDS case lists remained between 3.3 and 5.4 percent. These persons accounted for 69 percent of the identified infected donors, and their identification led to notification of 60 percent of potentially exposed recipients and 51 percent of known infected recipients. The crossreferencing of AIDS case listings with blood bank records was equally efficient for regions with low and high AIDS prevalence. National adoption of AIDS case list crossreferencing is recommended as an effective means of identifying previously unidentified infected recipients in an effort to limit the secondary spread of HIV infection.

Acquired Immunodeficiency Syndrome↗