J. O'h. Tobin

CYTOMEGALOVIRUS INFECTION IN THE ADULT

Aim of this report is to review the epidemiological and clinical features of HCMV infection in the adult. In all geographical areas high diffusion of HCMV infection involving all socioeconomic groups is observed; significant most elevated seroprevalence in North African and Asian ethnic groups is compared to Western populations is pointed out; besides, HCMV is absolutely the virus most frequently transmitted in the perinatal period. In the immunocompetent host, the HCMV infection is symptomless in the great majority of cases; in the symptomatic cases it shows the clinical features of a self-limited mononucleosis-like syndrome. In the immunocompromised patients, either in subjects infected with HIV or in onco-hematologic patients or recipients of solid organ or bone marrow transplants patients, HCMV infection leads to serious illness. The most frequent clinical pictures are: pneumonia, retinitis, hepatitis, polyradiculopathy, encephalitis, gastrointestinal tract disease, adrenal involvement; cases of myocarditis, pancreatitis, genitourinary localizations are less frequent. The clinical pictures are different in the different clinical groups: retinitis, in subjects with HIV infection and pneumonia in recipients of transplants, are respectively the main clinical manifestations; the mechanisms of such differences are not clearly defined. A to the diagnosis, the serological tests (evidence of IgM activity, IgG avidity) are useful in the immunocompetent host; whereas, in the immunocompromised host cytological detection (demonstration of typical cytological aspects and positive immunohistology for HCMV antigens) and/or virological detection (isolation of virus or evidence of viral antigens or viral DNA) are needed. The most used therapeutical choices are ganciclovir, foscarnet and cidofovir; these three drugs have similar antiviral effectiveness, but they show different outlines of toxicity and praticality of use.

Antibody titres in women six to eight years after the administration of RA27/3 and Cendehill rubella vaccines.

Titres of haemagglutination-inhibiting antibody have been measured repeatedly in young women during a period of 6-8 years after the administration of RA27/3 and Cendehill attenuated rubella vaccines. Mean antibody titres were initially 217 after RA27/3 and 159 after Cendehill, but the difference diminished after the first year. Antibody titres were subsequently well maintained in both groups and did not reveal any need for regular revaccination. Mean titres in the Cendehill group were partly maintained by symptomless reinfection which was commoner after Cendehill than after RA27/3. Significant falls in titre were equally common after both vaccines, but low titres of 30 or less were more frequent in subjects who had received Cendehill. Mean neutralizing antibody titres were initially 15.4 after RA27/3 vaccine and 9 after Cendehill. Titres remained higher after RA27/3 for 3 years, but the difference then diminished and became insignificant during the fifth year. Revaccination of women with low antibody titres produced significant increases in 69% of subjects when standard RA27/3 vaccine was used; a special preparation of RA27/3 of higher potency produced a similar number of rises (70%) but elicited higher titres and might occasionally be useful for revaccinating women who are likely to come into contact with rubella. Challenge with RA27/3 vaccine produced weaker responses in women who had experienced natural infection than in those whose antibody was vaccine-induced. Rises in antibody titre after revaccination consisted mainly of IgG, but traces of IgM antibody were detected in one vaccinee who had recently experienced natural reinfection and in 1 woman with naturally acquired antibody who had been challenged with high titre RA27/3 vaccine.

Viruses transmissible from laboratory animals to man

In a short review of the virus diseases capable of being transmitted from laboratory animals to man, it is possible to discuss only a few of the many agents to which attention will be drawn. Both those viruses that occur naturally in these animals, and those of danger when introduced experimentally, will be mentioned.

Legionella pneumophila: monoclonal antibody typing of clinical and environmental isolates.

Forty-one clinical isolates of Legionella pneumophila from sporadic cases of legionella pneumonia were collected from laboratories throughout the United Kingdom and were compared with 300 routine environmental isolates using two panels of monoclonal antibodies, covering serogroups 1-10. Eighty-five per cent of the clinical isolates belonged to the subgroup Pontiac of serogroup 1, whilst only 13% of the environmental isolates did. Approximately half of the clinical isolates tested came from patients with a recent history of foreign travel, mainly to southern Europe.

The post-mortem diagnosis of influenzal infection by fluorescent IgG, IgA and IgM antibody studies on necropsy blood

Necropsy blood from cases diagnosed as dying from influenza A was examined for specific antibody in the IgG, IgA and IgM fractions and a specific diagnosis of recent infection was made if either IgM or IgA antibody and low titres of IgG antibody were found. By these criteria a diagnostic rate of 77% was found in those cases from whom no virus was isolated. The use of infected cell monolayers grown on polytetrafluoroethylene-coated slides gave a simple method of carrying out these antibody assays, and the use of necropsy blood did not require any special methods of transport of specimens to the virus laboratory.