Some observations on complement-fixing antibodies to the EB virus.

Complement-fixing antibodies against an antigen prepared from the EB3 line of cultured Burkitt tumour cells were studied in various groups of patients and control individuals. Higher antibody titres were observed in patients with Burkitt's tumour than in African patients with other diagnoses. Significantly more medical students and nurses with a history of infectious mononucleosis possessed antibodies than those with no such history. Low levels of antibody were observed in patients during the acute phase of infectious mononucleosis and these levels were significantly lower than those in patients admitted to the same hospital with other diagnoses. During the early months following the acute phase of illness, EB complement-fixing antibodies remained stationary or apparently declined in titre but, in patients tested one or more years later, significantly higher antibody levels were observed.

Serum alpha-amylase isozymes in mumps: estimation of salivary and pancreatic isozymes by isoelectric focusing.

Serum alpha-amylase isozymes were separated into three major isozymes by thin-layer gel isoelectric focusing and detected by a starch-iodine zymogram procedure. Of the three groups of isozymes, one (S isozyme) corresponded to a salivary specific form, one (P isozyme) to a pancreatic specific form and the third (SP isozyme) to isozymes of similar isoelectric point common to both secretions. The levels of total alpha-amylase and of these three isozymes were estimated in the sera of 54 patients with mumps. Total alpha-amylase and salivary isozyme concentrations were greatly increased in the sera of all patients compared with controls. Pancreatic isozyme concentrations however, were only slightly increased and did not correlate with clinical pancreatitis. Indeed, in patients with mumps associated with pancreatitis, meningoencephalitis or orchitis, levels of total serum amylase, although higher than controls, were lower than levels in patients who presented solely with mumps sialadenitis.

Investigation of cross-infection in isolation wards of different design.

A survey was conducted in seven hospitals to assess the risk of cross-infection with the highly infectious air-borne diseases, varicella-zoster and measles, in isolation wards of different design. Existing wards and isolation techniques were found to afford a high degree of protection, but there was considerable variation in the incidence of cross-infection related to ward structure, ward practice and the availability of trained staff. Recommendations are made for the design of new isolation wards and for safe practice.

Negative-pressure plastic isolator for patients with dangerous infections.

A negative-pressure plastic isolator is effective for dealing with patients suffering from dangerous infections. So far it has been used to treat seven patients suspected of having infections due to Lassa, Marburg, or Ebola viruses. One patient spent 32 days in the isolator. The isolator was proved comfortable and acceptable to patients, and it gives the nursing and medical attendants a high degree of protection. All routine nursing and medical procedures can be carried out with minimal interference by the physical barrier, though it is not practicable to undertake artificial respiration or haemodialysis.

EB-virus-specific IgM and IgG antibodies in first-degree relatives of children with acute lymphoblastic leukaemia.

EB-virus-specific IgM and IgG antibodies (to virus capsid and soluble complement fixing antigens) were estimated in sera from mothers and sibs of children with acute lymphoblastic leukaemia, from patients with infectious mononucleosis, and from control induviduals. IgM antibodies were present in 12 of 16 mothers and 3 of 4 sibs of children with acute lymphoblastic leukaemia. They were also present in 14 of 16 patients with infectious mononucleosis, but in only 1 of 12 control individuals.

Assessment of patients with suspected viral haemorrhagic fever.

We reviewed our two-year (1967-7) experience of patients who might have had an African-derived haemorrhagic fever: only two out of 46 suspects had such infections, and these were successfully contained. Malaria was the most frequent diagnosis in these patients recently returned from Africa, especially if malarial prophylaxis had been inadequate. Altogether 26% of patients had become ill before travelling to Britain. It is impossible to ensure absolute safety even with draconian measures, but the degree of isolation recommended (based on epidemiological factors that included return from Africa within the previous three weeks, visiting country districts, exposure to possible cases, or infected material and illness despite adequate malarial prophylaxis) has proved effective and acceptable.

A case of Ebola virus infection.

In November 1976 an investigator at the Microbiological Research Establishment accidentally inoculated himself while processing material from patients in Africa who had been suffering from a haemorrhagic fever of unknown cause. He developed an illness closely resembling Marburg disease, and a virus was isolated from his blood that resembled Marburg virus but was distinct serologically. The course of the illness was mild and may have been modified by treatment with human interferon and convalescent serum. Convalescence was protracted; there was evidence of bone-marrow depression and virus was excreted in low titre for some weeks. Recovery was complete. Infection was contained by barrier-nursing techniques using a negative-pressure plastic isolator and infection did not spread to attendant staff or to the community.

A case of Lassa fever: clinical and virological findings.

Five days after arriving in London from Jos a young Nigerian women developed a severe and prolonged illness that proved to be Lassa fever. Virus was not detected in urine during the first three weeks but then appeared and reached a peak during the sixth week, with continuing excretion for 67 days after the onset of illness. Laboratory investigations showed evidence of extensive tissue damage and disturbance of clotting, but there was no serious bleeding and she eventually made a complete recovery despite a high sustained viraemia and severe liver damage. Convalescent serum was used in treatment but it was difficult to assess its contribution to the favourable outcome.

The safety of the Trexler isolator as judged by some physical and biological criteria: a report of experimental work at two centres.

We have assessed the effectiveness of flexible-film negative-pressure isolators by physical and biological means. We found that they afford a high degree of containment and therefore also of safety to hospital staff. We offer some recommendations on the operation of these isolators to ensure the optimum degree of protection.