Effect of nondisclosure of HIV status in sexual health clinics on unlinked anonymous HIV prevalence estimates in England, 2005-2009.

OBJECTIVES: To assess the extent of nondisclosure of known HIV status among sexual health clinic attendees and to quantify the impact of nondisclosure on estimates of undiagnosed HIV prevalence and of the proportion of patients remaining undiagnosed on leaving the clinic. METHODS: Serum samples from the unlinked anonymous survey of clinic attendees' archive were tested for antiretrovirals. Estimates of undiagnosed HIV were adjusted using the findings. RESULTS: Antiretrovirals were detected in 27% of samples taken from 'previously undiagnosed' attendees, who did not have an HIV test but were HIV positive as detected by unlinked anonymous testing, indicating nondisclosure; 24% of such samples from MSM had antiretrovirals present compared with 32% of heterosexual men and women. Antiretrovirals were detected in 33% of samples from London clinics and in 21% from non-London clinics. Following adjustment, the estimated prevalence of undiagnosed HIV decreased nonsignificantly from 3.04% (95% confidence interval 2.71-3.41) to 2.66% (2.35-3.01) among men who have sex with men (MSM), 0.31% (0.26-0.37) to 0.30% (0.25-0.36) in heterosexual men and 0.40% (0.35-0.46) to 0.37% (0.32-0.43) in women; 7% of MSM who do not have an HIV test at a clinic visit will be infected with HIV and remain unaware of their infection. CONCLUSION: Nondisclosure of HIV status to healthcare professionals occurs among clinic attendees. Adjustment for nondisclosure results in a small, nonsignificant decrease in the prevalence of undiagnosed HIV estimated from the unlinked anonymous survey in sexual health clinics. Testing the population of MSM not having an HIV test remains a priority as levels of undiagnosed HIV are high.

Non-disclosure of HIV status in UK sexual health clinics--a pilot study to identify non-disclosure within a national unlinked anonymous seroprevalence survey.

OBJECTIVES: To identify if HIV-infected individuals attending genitourinary clinics in the UK are not disclosing their HIV status, and to examine the potential utility of drug detection as a method to indicate non-disclosure. METHODS: HIV-positive samples from the unlinked anonymous seroprevalence survey from one London centre in 2009 had viral load (VL) assays performed to identify samples with VL below the level of detection (50 copies/ml, VLBLD) or <1000 copies/ml. After data matching, known HIV positives were excluded and the remaining samples analysed for the presence of a panel of antiretroviral drugs. RESULTS: Of 130 HIV-positive samples with sufficient clinical information and not undergoing an HIV test, 18 were classified as remaining undiagnosed after the clinic visit. Thirteen (72%, 95% CI: 47% to 90%) had a VLBLD (n=11) or VL <1000 copies/ml (n=2). Eight had sufficient volume to undergo ARV testing, and all were positive for the presence of drug; all with therapeutic levels of clinically appropriate combinations. CONCLUSIONS: Non-disclosure of HIV status occurs among individuals attending sexual health services in the UK. This study demonstrates the feasibility and utility of using both VL and ARV assays in serum samples. Furthermore, the close correlation of detection of ARV with VLBLD suggests drug detection would be a useful tool to monitor non-disclosure prospectively, thus enabling the use of stored serum samples in future studies. The extent to which these findings can be extrapolated to other settings, and the potential impact of non-disclosure on undiagnosed estimates warrants urgent prospective study.

Audit of tetanus prevention knowledge and practices in accident and emergency departments in England.

OBJECTIVES: To assess the knowledge and current tetanus prevention practices of various staff members in accident and emergency (A&E) departments. DESIGN, SETTING AND PARTICIPANTS: A structured questionnaire containing 16 questions on tetanus guidance, anti-tetanus practice, vaccination preparations and information on the population served by the department was sent to medical and nursing staff in A&E departments across England. RESULTS: 366 completed questionnaires from 67 hospitals were returned. 48.9% of the questionnaires were completed by the medical staff and 39.9% by the nursing staff at various grades. 75% of respondents said that their department had a local tetanus guideline, but only 29% stated that the tetanus guidelines were always followed. 31.4% of respondents said that injecting drug users were managed as a high-risk group in their department. Many respondents did not follow the national policy; they tended to err on the side of caution when it came to defining and treating tetanus-prone wounds, with 22.1% stating that they would consider any wound tetanus prone. Contrary to current Department of Health guidelines, 46.2% of respondents said that they would give a booster dose if the fifth dose had been given >10 years ago. CONCLUSIONS: There are clear differences between the recommended guidelines for tetanus prevention and current practice in A&E departments. The changes announced in 2002 do not seem to have been widely implemented. As a result, the apparent success of the national tetanus vaccination programme may be the result of more cautious clinical practice than would be expected from the UK policy. If national recommendations for tetanus are implemented in clinical practice, then the impact on control of the disease should be monitored closely.

Vaccine effectiveness estimates, 2004-2005 mumps outbreak, England.

The United Kingdom and United States have recently experienced large outbreaks of mumps, which raises concerns about vaccine effectiveness. The effectiveness of the mumps component of the measles, mumps, rubella (MMR) vaccine was estimated using the screening method. In England from January 2004 through March 2005, 312 cases of mumps were reported in children eligible to have received 2 doses of MMR vaccine. Of these children, 52 (16.7%) had received 1 dose of MMR vaccine, and 97 (31.1%) had received 2 doses. Vaccine effectiveness was 88% (95% confidence interval [CI] 83%-91%) for 1 dose and 95% (95% CI 93%-96%) for 2 doses. The effectiveness of 1 dose declined from 96% (95% CI 81%-99%) in 2-year-olds to 66% (95% CI 30%-83%) in 11- to 12-year-olds, and the effectiveness of 2 doses declined from 99% (95% CI 97%-99.5%) in 5- to 6-year-olds to 86% (95% CI 74%-93%) in 11- to 12-year-olds (p<0.001 for 1 or 2 doses). Waning immunity may contribute to mumps outbreaks in older vaccinated populations.