Strains of Neisseria meningitidis isolated from patients with meningitis or septicaemia without meningitis in Scotland during the years 1972–82 have been reviewed together with details of the age, sex, disease and outcome of the patients from whom they were isolated. A total of 1185 strains were isolated, of which 927 were examined at the Meningococcal Reference Laboratory (Scotland): 19·3% were of serogroup A, 63% of group B, 9·6% of group C, 6% of W135 and 1·6% of other groups. Non-groupable strains were rare. Disease was most common in the first years of life but there was a difference in the age distribution of disease due to the different serogroups, the proportion of disease due to group B being smaller in adults than that due to other serogroups. The overall mortality in meningitis was 7·5% and in septicaemia was 20·6%, although there were differences between the rates for the various serogroups. The serogroup distribution differed in disease as opposed to meningococci isolated from carriers although group B strains were predominant in both series. Overall, approximately 15% of strains were resistant to sulphadiazine, the proportion of resistant group A strains being higher than that of other serogroups.

Four hundred and seven clinical isolates of Escherichia coli were examined for the presence of plasmids. These isolates comprised 189 which were collected irrespective of antimicrobial resistance (VP) and 218 which were collected on the basis of high-level trimethoprim resistance (TPR). The VP isolates were divided into drug sensitive (VPS) and drug-resistant (VPR) subpopulations.

Plasmids were detected in 88% of VP isolates (81% of VPS and 94% of VPR) and 98% of TPR isolates. The distribution of plasmids in both groups and subpopulations was very similar. However, there were small but statistically significant differences between the plasmid distributions. These showed that more isolates in the resistant groups harboured plasmids than in the sensitive subpopulation (VPS) and that the number of plasmids carried by resistant isolates was greater. Multiple drug resistance was significantly more common among TPR isolates than the VPR subpopulation and this was paralleled by increased numbers of plasmids.

Fifty-eight per cent of VPR and 57% of TPR isolates transferred antimicrobial resistance and plasmids to E. coli K12. Of the R+ isolates, 60% carried small plasmids (MW < 20Md) and 52% of these co-transferred with R-plasmids. These results are discussed.

A method using an ammonia electrode is being developed for investigating the deamination of amino acids and amides by bacteria. Application of this method to Campylobacter jejuni and C. coli has led to the demonstration of d-asparaginase activity in some strains. This has allowed the subdivision of both species into d-asparaginase-positive and -negative biotypes. Even though the method is in the developmental stage, it was found to be generally reproducible and easy to perform. Areas for further improving the procedure have been identified. The ammonia electrode offers the theoretical possibility of investigating the breakdown of any amino acid by bacteria. It thus opens up a new and practical approach for separating species and strains, particularly in those bacterial groups that are difficult to subdivide by conventional means.

The results of a twelve-year study of Coxsackie B virus (CBV) infections in patients with a variety of acute and chronic illnesses are reported. CBVs were isolated from only 123 patients most of whom were children with respiratory illness. Virus diagnosis in adults was based mainly on the detection of significant rising or static high neutralizing antibody titrcs. Between 1972 and 1979 most investigations centred on patients with suspected viral heart disease, 12% of whom were found to have diagnostically significant CBV titres. In studies on patients with definite myo-pericarditis the number positive increased to 33%. In 1980 clinical interest switched to the possible role of CBV in myalgic encephalomyelitis (ME), an illness of diverse symptomatology. Investigation of suspected cases of ME in 1983 showed that 16% were serologically positive compared to 4% of normal adults in the West of Scotland. In patients with well-documented ME this figure rose to 41%.

The demand by clinicians for CBV neutralizing antibody tests has increased over the past twelve years and continues to escalate annually, especially in patients with chronic relapsing illness.

A comparison of neutralizing and immunofluorescent (IF) IgG antibody tests in 18 sera from 10 cases of hand, foot and mouth disease (HFMD) showed a variety of responses but all sera taken more than one week after infection had both neutralizing and IF IgG antibodies.

A survey of IF IgG antibody in 80 paediatric and 80 adult non-HFMD case sera gave antibody detection rates of 47·5% and 11·3% respectively. This difference could be attributed to a decline in IF IgG antibody with time after infection. Three point nine per cent of 2G sera from possible adult carditis cases had IF antibody suggesting that coxsackie A16 virus was not a common cause of adult carditis. Forty-eight point three per cent of 29 sera from cases of spontaneous abortion had detectable IF antibody, a rate similar to the paediatric sera and significantly greater than that in adult male (7·9%) and other adult female (13%) sera tested. This interesting observation requires further study.

Arginine has been shown to be essential for the replication of several orthopoxviruses in mouse sarcoma 180 cells and in chick embryo fibroblast cultures. Both host systems are characterized by their inabilities to utilize citrulline for the biosynthesis of arginine due to deficiencies in the requisite cellular enzymes and cell multiplication is absolutely dependent on the availability of exogenous arginine. Virus replication in such cells maintained with citrulline results from the induction of virus-specific enzymes. Significant virus yields in the absence of exogenous arginine or citrulline can arise from the replenishment of intracellular amino acid pools by increased utilization of arginyl residues in cellular proteins. The extent of the phenotypic expression of these characters in infected cells permitted significant discrimination between the viruses examined. Distinctions could be drawn between rabbitpox, ectromelia, cowpox, buffalopox and vaccinia strains. However, cowpox could not be distinguished from other viruses isolated from diseased animals in European zoos.

Hepatitis B core antigen (HBcAg) synthesised in Escherichia coli by recombinant DNA techniques was compared with HBcAg prepared from infected livrer tissue. The two antigens were used in radioimmunoassays (RIA) to detect antibody to HBcAg (anti-HBc) in sera from patients attending a clinic for sexually transmitted diseases. Out of 2151 sera tested, 260 were anti-HBc positive with both HBcAg preparations but seven were positive with the liver-derived antigen alone. Reasons for these discrepant results are discussed. The slight loss of sensitivity of the anti-HBc RIA using E. coli HBcAg was not considered significant when compared with the potential advantages of a synthetic antigen.

The presence of other hepatitis B markers in the 267 anti-HBc positive sera was determined: 25 contained HBsAg, 220 anti-HBs and, of the 22 that were HBsAg/anti-HBs negative, 12 contained anti-HBe. In the 10 remaining sera, anti-HBc was the only hepatitis B marker that could be found.

Since 1973 epidemiological surveillance of laboratory-confirmed hepatitis B virus infection has been undertaken in Scotland. During the ten-year period, 1973–82, 2893 persons with laboratory evidence of infection were reported and the number increased by almost threefold between the beginning and the end of this time. Males accounted for 66 % of the patients and intravenous drug abuse was the most commonly encountered risk factor. The low risk to laboratory staff is confirmed, but among National Health Service hospital staff nurses accounted for 54% of those reported.

The RNA genome of rotaviruses consists of 11 segments in four size-classes which can be separated by polyacrylamide gel electrophoresis, although 11 separate bands are not shown by all strains. We propose a cryptogram (Rotacode) based on the relative distance of migration of adjacent bands in each size-class for coding the typical pattern of each strain of virus. This provides a shorthand for recording details of each strain and for grouping electrophoretically similar strains.

Rotacode was found to be reliable and reproducible, with identical codes being obtained for the same samples in repeated experiments under code and by various observers. Rotacode was also used to analyse 189 strains obtained over a three-year period and differentiated 13 electrophoretypes. This confirms the considerable electrophoretic variability of wild strains.

An inactivated vaccine against respiratory syncytial virus (RSV) was compared with two live vaccines. The inactivated (GC) vaccine consisted of glutaraldehyde-fixed bovine nasal mucosa cells persistently infected with RSV and emulsified with oil adjuvant. The live vaccines were a modified virus (MV) derived from a bovine strain of RSV and a temperature-sensitive mutant (ts-1) derived from a human strain. The GC vaccine was inoculated subcutaneously into 12 calves and the live vaccines intramuscularly into eight calves each. Nine unvaccinated calves acted as controls. The vaccines were administered in two doses 3 weeks apart and all calves were challenged intranasally with 2 × 107 p.f.u. of bovine RSV 3 weeks after the second dose.

At the time of challenge calves given GC, MV and ts-1 vaccines had mean serum neutralizing antibody titres of 25, 19 and 2 respectively; mean titres of IgG1 antibody by radioimmunoassay were log10 4·5, 1·3 and 2·6 respectively and mean zone areas by single radial haemolysis (SRH) were 107, 27 and 36 mm2 respectively.

Eleven of 12 calves given GC vaccine were completely protected against challenge but all control animals and those given the two live vaccines were infected. The mean peak titre of virus in nasal swabs of control calves was 3.0 log10 p.f.u./ml and the mean duration of virus shedding was 6·8 days. Both these parameters were significantly reduced in animals given MV and ts-1 vaccines: mean peak titres were 2·1 and 2·4 log10 p.f.u./ml and mean duration of shedding was 3·4 and 3·3 days respectively.

Thus, protection correlated better with RSV antibody detected by radio-immunoassay and SRH than with neutralizing antibody. These results are discussed in relation to the possible mechanism by which protection was mediated.

Observations on the circulation of influenza viruses in Northern Greece during the winters of 1972/3 to 1982/3 are presented.

Influenza A viruses were detected every winter with the exception of those of 1973/4 and 1981/2, when neither type A nor type B was isolated. The strains of type A isolated during the study period were similar to those circulating world-wide over the same time scale.

Influenza B viruses were isolated only during the winters of 1972/3 and 1979/80; influenza A viruses were also circulating in the community at those times. The B strains detected were similar to those recorded world-wide during the period of study.

Hepatitis A is an acute inflammation of the liver caused by a virus (HAV) whose morphology and physical characteristics resemble members of the enterovirus group. The disease, which is characterized by fever, malaise, anorexia, nausea, abdominal discomfort and jaundice has an average incubation period of 28–30 days and is spread from person to person by the faecal-oral route. Common-vehicle outbreaks have been reported following contamination of food or water and epidemics may occur in closed communities (institutions, day-care centres) or in the general community when there is a breakdown of environmental sanitation. Many infections, especially in children, are subclinical; the case fatility rate for patients requiring hospitalization is low and long-term sequelae are unknown.

An outbreak of pharyngoconjunctival fever caused by adenovirus type 3 was studied in a boarding school for 800 boys aged 11–18 years. A total of 96 clinical cases were confirmed by laboratory tests. Clinical infection rates were higher in the younger boys but total infection rates did not vary with age. Previous infection provided 88% protection against reinfection.

The techniques of virus isolation, complement fixation and neutralization were compared in the diagnosis of cases. Virus isolation diagnosed 86% of confirmed cases. Where acute sera (collected at onset) and convalescent sera (collected within one month) were available complement fixation and neutralization tests each diagnosed 96% of cases.

A large nosocomial outbreak of keratoconjunctivitis due to adenovirus type 8 is described. Two hundred cases were identified, 123 by isolation of the virus and 77 by detecting HI antibodies in convalescent sera. Infection usually presented as a severe keratoconjunctivitis, and 107 (54%) of infected patients developed sub-epithelial corneal opacities. The majority (66%) of infections were acquired at the accident and emergency department attached to a large urban eye hospital when patients attended for other reasons; trauma to the eye, especially corneal foreign bodies, was the most frequent cause for the initial attendance. Transmission of virus within the family occurred in 13% of cases, but there was little spread outside family or hospital environments. The outbreak lasted from May to September, 1982, but it was not confirmed by isolation of the virus until the end of June when control measures were instituted. Delay in applying control measures was probably the major factor accounting for this large, prolonged outbreak of epidemic keratoconjunctivitis.

An outbreak of gastroenteritis caused by calicivirus began amongst residents and staff of an old persons home 24 hours after the proprietor's dog had been sick. Serological evidence suggests that the calicivirus isolated from one of the cases may be capable of infecting dogs as well as man. The virus strain responsible for this outbreak differs antigenically from those associated with two other outbreaks in the U.K. and one in Japan. The characteristic morphology of calicivirus is lost if stool is stored at – 70°C.

Antibody determinations against H3N2 and H1N1 type A influenza viruses were carried out on paired sera obtained from volunteers taking part in influenza virus vaccine studies, using both the haemagglutination-inhibition (HI) and single radial haemolysis (SRH) test. Good correlation between the HI and SRH test was found for both H3N2 and H1N1 antibody and the zone area increases corresponding to significant SRH antibody rises determined for both virus strains. In both H3N2 and H1N1 vaccine studies, intranasal infection of the volunteers with live attenuated viruses was involved and by the measurement of HI and SRH antibodies prior to and following infection, levels of antibody equating with protection against the infecting viruses could be estimated. For the HI test the antibody titres associated with 50% protection were 42 for H1N1, and 44 for H3N2 viruses; for the SRH test, 50% protection was associated with zone areas of 20·0–25·0 mm2 for both H1N1 and H3N2 viruses.

A virus of the Uukuniemi serogroup was isolated from various organs of a moribund kittiwake (Rissa tridactyla) and from ticks (Ixodes uriae) that were feeding on the bird. The kittiwake was found on Marsden beach, north-east England. This is the first virus in the family Bunyaviridae to have been isolated in England and only the second English arthropodborne virus after louping ill virus, family Togaviridae (Smith & Varma, 1981). The possibility of infection of humans by uukuviruses is discussed.

Features are described of a new staining method for the detection of Cryptosporidium oocysts in faeces. Smears, fixed in acid-methanol, are stained with heated safranin and counterstained with methylene blue. Oocysts stain a vivid orange-pink and are easily recognized. The method is rapid and simple with little source of error. The method is more sensitive than currently recommended Ziehl-Neelson methods; of 26 cases of cryptosporidiosis diagnosed by the new method only 19 were detected by acid-fast and only 11 by acid-alcohol-fast methods. Oocysts can be stained by safranin-methylene blue after concentration by various methods, in paraffin-embedded material, and after storage for months at various temperatures.

Fifty-four Rotterdam patients in which a primary infection with Campylobacter jejuni had been detected (index patients) were compared with 54 control subjects with regard to the consumption and preparation of foods 7 days before onset of illness and the keeping of pet animals. Significantly more index patients than controls had eaten chicken meat (47 v. 29; P = 0·0002), particularly at barbecues (14 v. 2; P = 0·0015). Marginally more index patients had eaten pork (47 v. 39; P = 0·048) or inadequately heated meat (13 v. 8), though in the last case numbers were too small to be statistically significant. The consumption of beef or mutton and outdoor eating (other than at barbecues) were essentially the same in both groups. There was no significant association with the keeping of pet animals, although a few more index patients had cage birds than controls (18 v. 12).

Twenty-one (15%) of 130 household contacts of index patients also suffered from diarrhoea during the same period. Circumstantial evidence pointed to a common source of infection with the index patient in 13 instances (nine households) and probable intrafamilial spread of infection in six instances.

Campylobacters were isolated from one of 110 swabs of kitchen work surfaces and eight of 107 swabs taken from lavatory bowls in index households.