Medical students' risk of infection with bloodborne viruses at home and abroad: questionnaire survey.

OBJECTIVE: To determine risks of exposure to and prevention of bloodborne virus infections among medical students during their elective period. DESIGN: Questionnaire study of students returning from their electives in 1997-8. SETTING: Urban teaching hospital. SUBJECTS: 220 final year medical students. RESULTS: 148 students (67%) returned questionnaires; all had been vaccinated against hepatitis B. 65 respondents (44%) had visited areas of relatively high endemicity for HIV, although 27 (42%) of these, all of whom had visited areas other than sub-Saharan Africa, were unaware of this. All but one had discussed their elective with advisers. Four students experienced percutaneous or mucosal exposure to potentially infectious body fluids, three in areas with a high prevalence of HIV infection. 44 respondents (30%) had experienced at least one such exposure during their clinical training; 75% of these exposures were unreported. 34% (13/38) students who visited areas known to have a high prevalence of HIV infection took with them a starter pack of zidovudine for post-exposure prophylaxis; 53% (20) took latex gloves and 63% (24) a medi-kit. None of the 27 students who were unaware that the areas they visited had a relatively high prevalence of HIV infection took zidovudine; only 15% (4) took gloves and 30% (8) a medi-kit. CONCLUSIONS: Medical schools should produce, regularly update, and implement guidelines regarding protection from bloodborne viruses during clinical studies, including electives. Education and training in infection control should start at the earliest opportunity.

Exposure to blood borne viruses and the hepatitis B vaccination status among healthcare workers in inner London.

Occupational exposure to blood borne viruses was examined during one year at a London teaching hospital. A total of 236 incidents occurred of which 83% were related to sharps, 32% were clearly avoidable, and 7% involved an infected source patient. Overall uptake of hepatitis B vaccine was 78% but it was particularly low in paramedical (70%) and domestic staff (45%). Continued effort needs to be applied to improve uptake of hepatitis B vaccine and to maintain high standards of control of infection.

Hepatitis B vaccine uptake among surgeons at a London teaching hospital: how well are we doing?

In order to determine the perceptions of surgical staff of the risks of hepatitis B virus (HBV) infection and its prevention through vaccination, and to assess frequency of 'sharps' injuries and compliance with the Department of Health (DoH) recommendations on vaccination, a questionnaire was distributed to surgical staff in the Guy's and St Thomas' Hospital Trust. Only 52 of the 88 surgeons who responded (59%) had documented vaccine-induced immunity to HBV. Eighty-five (97%) had received at least one dose of vaccine but 15 of these (18%) had failed to complete the course. Of the 70 surgeons completing the course, only 56 (80%) had had their immune responses checked and only 44 (63%) admitted sustaining a 'sharps' injury at least once a month, yet only 17% consistently reported these injuries. Those least likely to report were cardiothoracic and obstetric and gynaecology surgeons; these specialties also sustained the highest frequency of 'sharps' injuries. Ophthalmologists, who sustained the lowest rate of injury, were most likely to report. In conclusion, a significant number of surgeons appeared not to have completed a course of hepatitis B vaccine in the presence of a high frequency of 'sharps' injuries. Following the publication of DoH guidelines on protecting workers from HBV, it must be stressed that failure to comply with recommendations may have medicolegal implications.

Hepatitis A vaccine responses in HIV-positive persons with haemophilia.

The safety and immunogenicity of subcutaneously (s.c.) administered hepatitis A (HA) vaccine was evaluated in HIV positive and negative patients with haemophilia and healthy male controls. The vaccine was well tolerated. Seroconversion occurred among all controls after one dose of vaccine but was delayed among patients, particularly if HIV-positive-4 of 17 (24%) failed to respond to three doses of vaccine. Following the third dose of vaccine, geometric mean titres were significantly higher among controls (1354) than among HIV infected patients (204) (P < 0.05). Non-responders failed to develop an immune response following boosting with high titre vaccine. Patients with haemophilia may be vaccinated against HA s.c. but consideration should be given to ensuring that HIV-positive individuals with haemophilia and other immunosuppressed individuals should have their immune responses checked since additional booster doses or passive prophylaxis may be necessary in such individuals.

Clinical trial with inactivated hepatitis A vaccine and recommendations for its use.

OBJECTIVE: To compare the reactogenicity and immunogenicity of an inactivated hepatitis A vaccine in two different immunisation schedules. DESIGN: Randomised trial. SETTING: One London teaching hospital. SUBJECTS: 104 healthy adult volunteers (71 men, 33 women aged 19-60). INTERVENTIONS: Hepatitis A vaccine to group 1 (54 volunteers) at 0, 1, and 2 months and to group 2 (50) at 0, 1, and 6 months. MAIN OUTCOME MEASURES: Symptoms at and after each dose; liver function, hepatitis A virus specific serum immune response; and responses in saliva and parotid fluid in immunised volunteers and subjects with natural immunity. RESULTS: The vaccine was well tolerated; 97% (96/99) and 100% of those immunised developed serum antibody after one and two doses of vaccine respectively. Geometric mean titres increased progressively after each dose and were significantly higher in men but not women in group 2 after the third dose (ratio between geometric mean titres 0.265, 95% confidence interval 0.18 to 0.39; p less than 0.001). At one year this group-sex interaction was absent; geometric mean titres for both sexes were significantly higher in group 2 (ratio 0.330, 0.227 to 0.478; p less than 0.0001). Antibody responses were not significantly different between the groups at two years. Compared with naturally infected subjects immunised volunteers developed poor or undetectable virus specific IgG and IgA responses in saliva and parotid fluid. CONCLUSIONS: The vaccine was safe and highly immunogenic, and the differences in the immune responses in saliva and parotid fluid are unlikely to affect its efficacy.

Effect of hepatitis A vaccination schedules on immune response.

An inactivated hepatitis A vaccine was given to 104 seronegative volunteers aged between 19 and 60 years according to two schedules: 0, 1 and 2 months or 0, 1 and 6 months. The vaccine was well tolerated and 97 and 100% of vaccinees developed a serum antibody response following a single and two doses of vaccine respectively. Geometric mean titres increased progressively after each dose; responses following the 0, 1, 6 month schedule were significantly higher at one year but, among those tested at two years, these differences were less marked. Vaccinees, when compared with naturally infected persons, developed poor or undetectable hepatitis-A-virus-specific immunoglobulin G and A antibody responses in saliva and parotid fluid. Such differences are, however, unlikely to affect the protective efficacy of the vaccine.

Chronic relapsing pericarditis and dilated cardiomyopathy: serological evidence of persistent enterovirus infection.

By means of two different IgM-capture assays, enterovirus-specific IgM responses were shown in 9 of 14 (64%) patients with chronic relapsing pericarditis. This finding suggests persistent enterovirus infection, particularly coxsackie B virus infection. IgM responses persisted for at least 1 year and for up to 10 years after onset of symptoms. In contrast, patients with acute enterovirus infections, including acute pericarditis, had transient responses. Among patients with acute pericarditis, the level of IgM antibody was significantly higher in those who subsequently relapsed (mean 1.21, range 0.6-2.0 optical density [OD] units) than in those who did not (0.4, 0.2-0.9 OD units; p less than 0.01). Of 86 patients with dilated cardiomyopathy, 28 (33%) showed enterovirus-specific IgM responses which were present for up to 19 months before transplantation and persisted up to 4 years afterwards. Although the distribution of HLA types in these patients was similar to that in the general population, the frequency of the HLA A2 haplotype was significantly higher in those who were IgM positive. IgM antibody was significantly more common in those who had had symptoms for longer than a year before transplantation than in those with a shorter duration of symptoms (1 of 21 vs 8 of 23; p less than 0.02). Persistent virus-specific serum IgA responses were also shown in patients with chronic cardiac disease.

Hepatitis B infections after gynaecological surgery.

When acute hepatitis B developed in 3 patients who had had gynaecological surgery, the surgeon was found to be a carrier of hepatitis B e antigen. Of 268 patients operated on by this surgeon in one hospital, 247 were screened for markers of recent or current hepatitis B. 22 (9%) had such markers, associated with symptoms in 5. The operations carrying greatest risk of infection were hysterectomy (10/42) and caesarean section (10/51). These findings strengthen the case for vaccination of all surgeons and medical students against hepatitis B.

Patients with suspected Lassa fever in London during 1984: problems in their management at St Thomas's Hospital.

During 1984, 23 patients in whom a diagnosis of viral haemorrhagic fever was considered presented to the accident and emergency department at St Thomas's Hospital. There were no confirmed cases of viral haemorrhagic fever. Nine patients were transferred to Coppett's Wood Hospital, the nearest specially designated high security isolation unit. Malaria was the final diagnosis in 14, and in six this diagnosis was confirmed only after examining repeated smears at Coppett's Wood Hospital. Transferral of patients to such units is time consuming, expensive, and often unnecessary. Specially designated isolation units in district general hospitals and all teaching hospitals would simplify and improve the care not only of patients with a possible viral haemorrhagic fever but also patients with tuberculosis, multiply resistant staphylococcal infections, and viral infections that may be hazardous if transmitted to immunocompromised patients.