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OBJECTIVES: To investigate epidemiological, social, diagnostic and economic aspects of chlamydia screening in non-genitourinary medicine settings. METHODS: Linked studies around a cross-sectional population-based survey of adult men and women invited to collect urine and (for women) vulvovaginal swab specimens at home and mail these to a laboratory for testing for Chlamydia trachomatis. Specimens were used in laboratory evaluations of an amplified enzyme immunoassay (PCE EIA) and two nucleic acid amplification tests [Cobas polymerase chain reaction (PCR), Becton Dickinson strand displacement amplification (SDA)]. Chlamydia-positive cases and two negative controls completed a risk factor questionnaire. Chlamydia-positive cases were invited into a randomised controlled trial of partner notification strategies. Samples of individuals testing negative completed psychological questionnaires before and after screening. In-depth interviews were conducted at all stages of screening. Chlamydia transmission and cost-effectiveness of screening were investigated in a transmission dynamic model. SETTING AND PARTICIPANTS: General population in the Bristol and Birmingham areas of England. In total, 19,773 women and men aged 16-39 years were randomly selected from 27 general practice lists. RESULTS: Screening invitations reached 73% (14,382/19,773). Uptake (4731 participants), weighted for sampling, was 39.5% (95% CI 37.7, 40.8%) in women and 29.5% (95% CI 28.0, 31.0%) in men aged 16-39 years. Chlamydia prevalence (219 positive results) in 16-24 year olds was 6.2% (95% CI 4.9, 7.8%) in women and 5.3% (95% CI 4.4, 6.3%) in men. The case-control study did not identify any additional factors that would help target screening. Screening did not adversely affect anxiety, depression or self-esteem. Participants welcomed the convenience and privacy of home-sampling. The relative sensitivity of PCR on male urine specimens was 100% (95% CI 89.1, 100%). The combined relative sensitivities of PCR and SDA using female urine and vulvovaginal swabs were 91.8% (86.1, 95.7, 134/146) and 97.3% (93.1, 99.2%, 142/146). A total of 140 people (74% of eligible) participated in the randomised trial. Compared with referral to a genitourinary medicine clinic, partner notification by practice nurses resulted in 12.4% (95% CI -3.7, 28.6%) more patients with at least one partner treated and 22.0% (95% CI 6.1, 37.8%) more patients with all partners treated. The health service and patients costs (2005 prices) of home-based postal chlamydia screening were 21.47 pounds (95% CI 19.91 pounds, 25.99) per screening invitation and 28.56 pounds (95% CI 22.10 pounds, 30.43) per accepted offer. Preliminary modelling found an incremental cost-effectiveness ratio (2003 prices) comparing screening men and women annually to no screening in the base case of 27,000 pounds/major outcome averted at 8 years. If estimated screening uptake and pelvic inflammatory disease incidence were increased, the cost-effectiveness ratio fell to 3700 pounds/major outcome averted. CONCLUSIONS: Proactive screening for chlamydia in women and men using home-collected specimens was feasible and acceptable. Chlamydia prevalence rates in men and women in the general population are similar. Nucleic acid amplification tests can be used on first-catch urine specimens and vulvovaginal swabs. The administrative costs of proactive screening were similar to those for opportunistic screening. Using empirical estimates of screening uptake and incidence of complications, screening was not cost-effective.

An outbreak of gastroenteritis affected a school attended by children aged 4–11 years. Epidemiological features suggested this was due to Norwalk-like virus (NLV) and this was confirmed by polymerase chain reaction (PCR). Nucleotide sequence analysis of the PCR amplicons revealed identical strains in all five positive stool samples. Pupils were significantly more likely to become ill following an episode of vomiting within their classroom (adjusted odds ratio 4·1, 95% CI 1·8–9·3). The times from exposure to illness were consistent with direct infection from aerosolized viral particles where exposure to vomiting was high.Cleaning with quaternary ammonium preparations made no impact on the course of the outbreak. However, the outbreak stopped after the school closed for 4 days and was cleaned using chlorine-based agents. This study confirms the importance of vomiting in the transmission of NLV and provides evidence that direct infection with aerosolized viral particles occurs.

Some patients exposed to Q fever (Coxiella burnetii infection) may develop chronic fatigue.To determine whether subjects involved in the West Midlands Q fever outbreak of 1989 had increased fatigue, compared to non-exposed controls, 10 years after exposure.Matched cohort study comparing cases to age-, sex- and smoking-history-matched controls not exposed to Q fever.A postal questionnaire was sent to subjects at home, followed by further assessment in hospital, including a physical examination and blood tests.Of 108 Q-exposed subjects, 70 (64.8%) had fatigue, 37 idiopathic chronic fatigue (ICF) (34.3%), vs. 29/80 (36.3%) and 12 (15.0%), respectively, in controls. In 77 matched pairs, fatigue was commoner in Q-exposed subjects than in controls: 50 (64.9%) vs. 27 (35.1%), p0.0001. ICF was found in 25 (32.5%) of Q-exposed patients and 11(14.3%) of controls (p=0.01). There were 36 (46.8%) GHQ cases in Q-exposed subjects, vs. 18 (23.4%) controls (p=0.004). A matched analysis of those more intensively studied showed fatigue in 48 (66.7%) Q-exposed patients and 25 (34.7%) controls, (p0.0001), ICF in 25 (34.7%) Q-exposed and 10 (13.9%) controls (p=0.004), and chronic fatigue syndrome (CFS) in 14 (19.4%) Q-exposed patients and three (4.2%) controls (p=0.003). Thirty-four (47.2%) Q-exposed patients were GHQ cases compared to 17 (23.6%) controls (p=0.004).Subjects who were exposed to Coxiella in 1989 had more fatigue than did controls, and some fulfilled the criteria for CFS. Whether this is due to ongoing antigen persistence or to the psychological effects of prolonged medical follow-up is uncertain.

OBJECTIVES: Although rubella serosusceptibility among women of reproductive age in West Africa ranges from 10% to 30%, congenital rubella syndrome has not been reported. In Ghana, rubella immunization and serologic testing are unavailable. Our objectives were to identify congenital rubella syndrome cases, ascertain rubella antibody seroprevalence during pregnancy, and recommend strategies for congenital rubella syndrome surveillance. METHODS: Congenital rubella syndrome cases were identified through prospective surveillance and retrospective surveys of hospital records. A rubella serosurvey of pregnant urban and rural women was performed. RESULTS: Eighteen infants born within a 5-month period met the congenital rubella syndrome case definitions, coinciding with a 9-fold increase in presentation of infantile congenital cataract. The congenital rubella syndrome rate for this otherwise unrecorded rubella epidemic was conservatively estimated to be 0.8 per 1000 live births. A postepidemic rubella immunity rate of 92.6% was documented among 405 pregnant women; susceptibility was significantly associated with younger age (P = .000) and ethnicity (northern tribes, P = .024). CONCLUSIONS: Congenital rubella syndrome occurs in Ghana but is not reported. Information about congenital rubella syndrome and rubella in sub-Saharan Africa is needed to evaluate inclusion of rubella vaccine in proposed measles control campaigns.

Small round structured viruses (SRSVs, Norwalk-like viruses, NLVs) are the most common cause of outbreaks of gastro-enteritis in hospitals and also cause outbreaks in other settings such as schools, hotels, nursing homes and cruise ships. Hospital outbreaks often lead to ward closure and major disruption in hospital activity. Outbreaks usually affect both patients and staff, sometimes with attack rates in excess of 50%. For this reason, staff shortages can be severe, particularly if several wards are involved at the same time. SRSVs may be spread by several routes: faecal-oral; vomiting/aerosols; food and water. Viruses may be introduced into the ward environment by any of these routes and then propagated by person-to-person spread. In an outbreak setting, the diagnosis can usually be made rapidly and confidently on clinical and epidemiological grounds, particularly if vomiting is a prominent symptom. By the time an SRSV outbreak has been recognized at ward level, most susceptible individuals will have been exposed to the virus and infection control efforts must prioritize the prevention of spread of infection to other clinical areas bycontainment of infected/exposed individuals (especially the prevention of patient and staff movements to other areas), hand-hygiene and effective environmental decontamination. This report of the Public Health Laboratory Service Viral Gastro-enteritis Working Group reviews the epidemiology of outbreaks of infection due to SRSVs and makes recommendations for their management in the hospital setting. The basic principles which underpin these recommendations will also be applicable to the management of some community-based institutional outbreaks.

This study retrospectively reviews infections over a 7-year period in 60 consecutive adults (median age 25 years) undergoing their first unrelated donor bone marrow transplant (UD-BMT). T-cell depletion was employed in 93%. More than half the patients had one or more severe, potentially life-threatening, infections. There was a high incidence of invasive fungal infections (Aspergillus 17, Candida four), despite the use of itraconazole or amphotericin prophylaxis. Ten Aspergillus infections occurred beyond 100 d. Two patients (11%) with invasive aspergillosis survived. Clustering of infections was noted, with invasive fungal infections significantly associated with bacteraemias (OR 3.73, P = 0.06) and multiple viral infections (OR 4.25, P = 0.05). There were 21 severe viral infections in 16 patients, with CMV disease occurring in four patients only; viral pneumonitis was predominantly due to ‘community respiratory’ viruses. Most early bacteraemias (68%) were due to Gram-positive organisms. The majority of episodes of Gram-negative sepsis were caused by non-fastidious non-fermentative bacteria, such as Pseudomonas spp. and Acinetobacterspp., historically regarded as organisms of low pathogenicity. In patients with successful engraftment and minimal graft-versus-host disease, late infections suggestive of continued immune dysfunction (shingles, recurrent lower respiratory infections, Salmonella enteritis and extensive warts) were common.

In August 1994, 30 of 135 (23%) bakery plant employees and over 100 people from South Wales and Bristol in the United Kingdom, were affected by an outbreak of gastroenteritis. Epidemiological studies of employees and three community clusters found illness in employees to be associated with drinking cold water at the bakery (relative risk 3·3, 95%, CI 1·6–7·0), and in community cases with eating custard slices (relative risk 19·8, 95%, CI 2·9–135·1) from a variety of stores supplied by one particular bakery. Small round-structured viruses (SRSV) were identified in stool specimens from 4 employees and 7 community cases. Analysis of the polymerase and capsid regions of the SRSV genome by reverse transcription-polymerase chain reaction (RT-PCR) demonstrated viruses of both genogroups (1 and 2) each with several different nucleotide sequences. The heterogeneity of the viruses identified in the outbreak suggests that dried custard mix may have been inadvertently reconstituted with contaminated water. The incident shows how secondary food contamination can cause wide-scale community gastroenteritis outbreaks, and demonstrates the ability of molecular techniques to support classical epidemiological methods in outbreak investigations.

A recent study showed that 43% of a population in the United Kingdom were seropositive for group C rotavirus. The higher than expected incidence may be due to limited diagnosis of acute human group C rotavirus infections because no routine test is available. Human group C rotavirus infections are routinely diagnosed by electron microscopy (EM) and a negative group A rotavirus enzyme-linked immunosorbent assay (ELISA) result. An antigen-detection ELISA was developed with hyperimmune antibodies raised to human group C rotavirus recombinant VP6 (Bristol strain) expressed in insect cells. The assay was used to screen fecal samples to determine the prevalence of group C rotavirus infection. Samples positive by ELISA were confirmed by EM, polyacrylamide gel electrophoresis of double-stranded RNA, or detection of the VP6 gene by reverse transcription-PCR. Retrospective analysis indicated a 1 to 2% detection rate of positivity among samples from patients with acute diarrhea.

Recent reports suggest an increased incidence of cytomegalovirus (CMV) infection in recipients of unrelated donor (UD) bone marrow transplantation (BMT). In this study we have collated the incidence of CMV infection and disease in sequential UD (n = 119) and related donor (RD; n = 79) BMT performed in a single institution over a 7-year period. Low-risk patients (CMV seronegative recipient and donor) accounted for 51% of UD BMT (n = 61) and 62% of RD BMT (n = 49), with CMV excretion documented in one RD BMT only. The remaining high-risk patients received identical prophylaxis regimens with aciclovir and intravenous immunoglobulin (IVIG). Two groups consisting of 58 UD BMT (median age 9.0 years, range 0.7–45.3 years) and 30 RD BMT (median age 13.6 years, range 1.6–47.6 years) were analysed. CMV reactivation/re-infection was documented in 15 UD BMT (26%) and 10 RD BMT (33%) (P = 0.72), and CMV disease in four UD BMT (8%) and four RD BMT (13%) (P = 0.533). In this series the risk of CMV excretion and disease following UD BMT was similar to that following RD BMT.

Background Q fever is a world-wide condition caused by the rickettsia Coxiella bumetii. It appears more prevalent in agrarian communities and may have serious sequelae. Methods A descriptive, cross-sectional, observational study using a randomly selected group of the adult working practice population in a rural practice in West Wales was devised. An immunofluores cence test, which identified past infection, was used to look for associations between C. bumetii seropositivity and farm-related or social activities, and to compare the findings with those of other studies. An attempt was made to establish a clinical profile for the illness Q fever. Results Twenty-one subjects were found to be seropositive to C. bumetii. No definite consistent clinical features were identified. Farming was undoubtedly a risk factor for the disease, maybe with other related factors also important. There was a possibility that alcohol had a protective effect. No sinister sequelae were described. Conclusions Q fever occurs more frequently in farmers than in non-farmers, but was less common than previously thought. Is Q fever accurately described in medical textbooks? A case is made for a more co-operative approach between primary carers and epidemiologists in the study of illnesses in populations.

The gene coding for the major inner capsid protein VP6 of human group C rotavirus was cloned into baculovirus using the pBlueBac2 vector and expressed in insect cells. When cultured in High Five cells, VP6 was expressed at a high level and exported to the cell culture medium. Purified VP6 was used to immunise rabbits. Hyperimmune rabbit serum, which reacted with native human group C rotavirus in infected cells, was used to develop and optimise an EIA for the detection of antibodies to group C rotavirus using the recombinant VP6 as a source of antigen. In a local epidemiological survey of 1000 sera grouped by age, an average of 43% of samples were found to have antibodies to human group C rotavirus with the highest proportion (66%) in the 71-75 year age group. In comparison, 97% of adults and 85% of children had antibodies to recombinant VP6 from the bovine RF strain of group A rotavirus. These results suggest that infection with human group C rotavirus is a common occurrence despite the apparent rarity of reports of human group C rotavirus in clinical samples from patients with gastroenteritis.

An enteric calicivirus showing the classic cup-shaped surface morphology was identified in a stool sample obtained from a child with symptoms of acute gastroenteritis (Portishead virus, PHV). Genomic RNA was extracted directly from the PHV stool sample and amplified by RT-PCR using primers based on the Manchester isolate of HuCV. The 3′ terminus of the cDNA was defined by homopolymer tailing with dATP and revealed an additional 165 nucleotides suggesting that the previously determined Manchester HuCV (MV) genome sequence was incomplete. Homopolymer tailing of MV cDNA primed using sequence data from the 5′ terminus of PHV allowed extension of the MV genome by a further 165 nucleotides thereby increasing the overall genome length to 7431 nucleotides and resulting in an additional 72 amino acids at the N-terminus of the polyprotein. A conserved sequence motif typical of other caliciviruses was also identified at the extreme 5′-terminus of the genome.

Sequence comparison of the RNA-dependent RNA polymerases of small round-structured viruses (SRSVs) from 10 recent U.K. outbreaks of gastroenteritis revealed significant genetic variation. Computer analyses indicated that these viruses can be divided into two discrete groups. SRSV group I contains the previously characterized antigenic type 1 Norwalk and type 3 Southampton viruses. The amino acid sequences of the RNA polymerase, capsid and ORF3 of these two viruses are relatively similar (about 92%, 69% and 72% amino acid identity, respectively). A representative member of group II SRSVs, Bristol virus, was subjected to a detailed genetic analysis. Bristol virus is a recent antigenic type 2 isolate from a U.K. hospital outbreak of gastroenteritis. Using a single clinical sample the 3'-terminal 3881 nucleotide cDNA sequence [excluding the poly(A) tail] of this virus was determined. Analysis of the sequence revealed significant differences from those of group I viruses with the RNA polymerase region, capsid and ORF3 showing only about 62%, 43% and 30% amino acid identity respectively with the equivalent proteins of the Norwalk and Southampton viruses. These data suggest that the morphologically identical SRSVs belong to at least two genetically distinct groups.

In the spring of 1989 the largest outbreak of acute Q fever recorded in the United Kingdom occurred in Solihull and surrounding areas of the West Midlands. The diagnosis was confirmed in 147 people, mainly males of working age. Windborne spread from farmland to the south of the urban area was the most likely route of infection. Fever was the commonest symptom, seen in 101 102 (99%) cases, followed by weight loss reported by 83 101 (82%). Headache, often severe, was experienced by 69 101 (68%). The commonest respiratory symptom was breathlessness, 65 102 (64%), followed by cough, 52 102 (51%), and chest pain, 46 102 (45%). Neurological features, seen in 23% of cases, were more prominent in this outbreak than is commonly recognized. Persisting ill health 6 months following the acute episode not due to chronic Q fever was also a prominent feature of this largely urban outbreak.

Of 147 patients with acute Q fever diagnosed during a major outbreak in Birmingham, England, in early summer 1989, 41 provided sets of sera which allowed us to make a detailed analysis of the primary humoral immune response. Antibody titers specific for Coxiella burnetii were measured by the complement fixation test and by an immunoglobulin M (IgM)- and IgG-specific indirect immunofluorescence test. The relative avidity of specific IgGs was determined by the indirect immunofluorescence test with and without treatment of antigen-antibody complexes with 8 M urea. The IgG subclass responses after primary infection and their avidities were also determined for a limited number of paired serum specimens. Specific IgM titers persisted for more than 6 months in the majority of cases and were therefore not a sufficient criterion for the diagnosis of recent infection. However, for serial samples the antibody titer ratios (IgG/IgM) and the ratios (IgG titer with treatment/IgG titer without treatment) that indicated relative avidity changed significantly, depending on the time postinfection. Within the IgG class, the C. burnetii-specific antibody response over time was almost exclusively represented by subclass 1 molecules, which thus showed affinity maturation.

A novel, sequence-independent strategy has been developed for the amplification of full-length cDNA copies of the genes of double-stranded RNA (dsRNA) viruses. Using human (Bristol) group C rotavirus as an example, a single amino-linked modified oligonucleotide (primer 1) was ligated to either end of each dsRNA genome segment by using T4 RNA ligase. Following reverse transcription, annealing, and repair of cDNA strands, amplification of the viral dsRNA genome was accomplished by polymerase chain reaction using a single complementary oligonucleotide (primer 2). Northern (RNA) hybridization of cDNA to virus dsRNA indicated that it was possible to generate cDNA representing the complete genome from very small clinical samples. This technique was used to determine the complete nucleotide sequence (728 bp) and coding assignment of gene 10, which revealed an open reading frame of 212 amino acids with limited homology to NS26 from human group A rotavirus. In contrast to previous tailing methods, the addition of one defined primer allowed unequivocal identification of terminal nucleotides and should be generally applicable to viruses with segmented dsRNA genomes and especially for analysis of clinical samples, for which very limited quantities of biological material are available.

SUMMARYIn 1985 an outbreak of ornithosis affected 13 of 80 (16%) workers in a duck-processing plant. New employees were three times more likely to become cases than established employees. The highest attack rate was in those on the production line. Following the outbreak, an occupational health scheme was set up to monitor the health of new recruits to the company. Serological evidence of recent infection was demonstrated in 18 of 37 (49%) new employees tested in the first 3 months of employment. Five (14%) also had clinical evidence of ornithosis. Veterinary investigation of the ducks demonstrated a high proportion with asymptomatic chlamydial infection. It is suggested that ornithosis may be more common in duck processors than ins processors than is currently supposed. Strategies to reduce occupational risks are discussed.

Summary Sputum induction using nebulised hypertonic saline was performed in two groups of immunocompromised children, one group with symptoms of respiratory infection and one group without. The asymptomatic group were bone marrow transplant (BMT) recipients, all seropositive for cytomegalovirus infection (CMV). Organisms were identified in three of 14 induced sputum specimens obtained from the symptomatic group (CMV N=1, Haemophilus influenzae N = 2), but in none of 12 specimens from the asymptomatic group. Adverse effects encountered were minor. Four symptomatic patients with negative induced sputum samples underwent bronchoalveolar lavage, and no further organisms were identified. Sputum induction can be a useful adjunct to the diagnosis of respiratory pathogens in this group of patients.

The VP6 gene of human group C rotavirus was cloned and sequenced. Hybridization to the human group C and the porcine group C/Cowden dsRNA genomes assigned this coding sequence to segment 5. The complete human VP6 sequence contained an open reading frame of 1185 nucleotides (395 amino acids; deduced Mr 44,669 Da). The protein sequence demonstrated low homology with the group A VP6 sequences (41.7 to 42.7%) and high homology (88.9%) with the porcine group C VP6 sequence. However, the protein sequence alignments revealed a region of 10 amino acids that were significantly different between the human and the porcine group C viruses.

We adapted the polymerase chain reaction (PCR) to detect the noncultivatable group B and C rotaviruses and introduced a simple and convenient technique to purify viral RNA from stool specimens. Double-stranded RNA present in stool extracts was purified by adsorption to hydroxyapatite and was used as the template for reverse transcription and polymerase amplification. Primer pairs specific for group B (gene 8) and group C (gene 6) rotaviruses were selected to amplify group-characteristic sizes of cDNA copies readily identifiable in ethidium bromide-stained agarose gels. These primer pairs were used separately in individual PCR assays or were pooled with a primer pair specific for group A rotavirus (gene 9) in a combined PCR assay for the simultaneous detection of all three rotavirus groups. The method was very sensitive and was used to identify both human and porcine strains of group B and C rotaviruses in stool specimens. A second PCR amplification with internal group-specific primers served to increase further the sensitivity of the test and to confirm the diagnostic results obtained in the first amplification.

SUMMARYBetween 1972 and 1988 we have serologically confirmed 103Coxiella burnetiiinfections: 46 were acute, 5 were chronic, 52 represented past infections. Details of 61 cases are presented.Of acute cases 80 % had respiratory involvement; at least 63 % had pneumonias. The incidence (22%) of neurological complications was of particular interest; 40% of these patients had prolonged sequelae. One acutely ill patient died of fulminating hepatitis. Patients with pre-existing pathology or immunosuppression were especially susceptible toC. burnetii.In the absence of acute sera, the complement fixation test alone provided inadequate differentiation between recent and past Q fever: phase II titres persisted at ⋝ 80 for more than 1 year after the acute infection in 15 cases; maximum duration of persistence was 14 years. Three patients acquired high phase I titres.Only 5% of cases had chronic Q fever, but in view of the diverse sequelae observed in this series, we suggest that long-term serological and clinical follow-up of all cases of Q fever is fully justified.

A family outbreak of gastroenteritis involving three adults and three children is described in which diarrhoea and vomiting were the main clinical features. One infant died in whom no pathogens could be detected in either small or large intestinal postmortem samples. Stool samples from two symptomatic siblings contained rotaviruses as demonstrated by electron microscopy. Both of these faecal samples were negative when assayed in a group A specific rotavirus enzyme-linked immunosorbent assay (ELISA) and subsequent genomic analysis of these rotaviruses was suggestive of group C rotavirus. Serological evidence showed that these atypical rotaviruses were members of serogroup C. Other atypical rotaviruses in faecal samples from sporadic cases in symptomatic children were detected over a similar time period and location. These had electrophoretic RNA profiles similar to those in the family outbreak. Furthermore, seroepidemiological studies detected group C rotavirus antibody in blood donors resident in the location of the family outbreak.

The clinical, serological and electron microscopic findings in a 47 year old woman with bioprosthetic valve coxiella endocarditis occurring 15 years after streptococcal endocarditis are described. The patient underwent valvular surgery a total of four times to control symptoms and remains well on medical therapy more than two years after her last operation.

Background: In early 2002 reports of outbreaks of gastroenteritis reached unprecedented levels in the UK. Forty five Norovirus outbreaks were reported in January 2002. Objectives: The objective of the study was to determine whether the outbreaks were Noroviral in origin and if so whether they represented a homogeneous or heterogeneous collection of Noroviruses by applying EIA and sequence analysis to representative faecal samples. Study design: Faecal specimens were collected during the week of highest incidence from 21 outbreaks in a variety of health care settings including hospitals and nursing homes. The outbreaks occurred in geographically distinct regions of the UK and samples were collected by reference laboratories in Glasgow, Manchester, Bristol and Southampton. Results: The samples were all positive for Noroviruses by negative stain electron microscopy (EM) and Lordsdale virus (LV) EIA, therefore reverse transcriptase polymerase chain reaction (RT-PCR) amplification and nucleotide sequencing of the Norovirus RNA polymerase gene was performed on amplicons from samples of each of the 21 outbreaks to investigate the nature and extent of diversity. All samples were very closely related to the reference Lordsdale virus genome sequence. LV was first discovered during an hospital outbreak of gastroenteritis in Southampton General Hospital in March 1993. Conclusions: Noroviruses are a major cause of outbreaks of gastroenteritis in health care settings. LV is the predominant Norovirus in the UK and was detected in outbreaks that occurred during the national peak of gastroenteritis reports in January 2002.

Background: Screening for Chlamydia trachomatis specific antibodies is valuable in diagnosing asymptomatic pelvic inflammatory disease (PID) and tubal damage following repeated episodes of PID. The assays in current use are unsuitable for screening large numbers of samples so there is a need to develop more suitable assays. Aims: To compare the performance of several commercial C trachomatis enzyme immunoassays (EIAs) (SeroCT, C trachopep, Medac p-EIA, Vircell and Labsystems C trachomatis IgG EIAs) using major outer membrane protein (MOMP), an inactivated organism EIA (Genzyme Virotech EIA), and a genus specific EIA (Platelia Chlamydia IgG) with the whole cell inclusion immunofluorescence (WIF) assay. In addition, to adapt, using time resolved fluorescence technology, the assay showing the highest correlation with WIF. Methods: Ninety sera from patients presenting with ectopic pregnancies, 187 sera from those with a variety of types of infertility, 33 sera from cases of PID where a fourfold rise in WIF titre occurred, and 90 sera from antenatal clinic attenders were tested. A panel of 36 sera from laboratory diagnosed cases of Chlamydia psittaci/Chlamydia pneumoniae infection was also tested. Results: The Genzyme Virotech EIA showed the highest rank correlation coefficient (0.82) with WIF, particularly at high WIF titres. The MOMP specific assays varied in their correlation with WIF, with rank correlation coefficients ranging from 0.70 (Medac p-EIA) to 0.80 (Vircell EIA). The Genzyme Virotech assay showed poor specificity (5.6%; 95% confidence interval (CI), 0.68% to 18.7%)—it was reactive with 34 of the panel of 36 C psittaci/C pneumoniae positive sera. The MOMP based EIAs showed high specificity, particularly the Medac p-ELISA (97.2%; 95% CI, 85.5% to 99.9%)—only one serum was reactive. In view of the good correlation between WIF and the Genzyme Virotech EIA, a time resolved fluorescence immunoassay (TRFIA) was developed using the Genzyme Virotech antigen. Using an appropriate cut off the TRFIA assay showed excellent correlation with WIF. Conclusions: The TRFIA assay may be useful as a screening assay, possibly in conjunction with one of the highly specific EIAs studied (for example, Medac p-EIA) to confirm the antibody specificity of sera selected by the screening assay.

Chlamydia pneumoniae is a common cause of community acquired respiratory infections such as pharyngitis, bronchitis, and pneumonia. The detection of C. pneumoniae in 17 of 19 brain samples from patients diagnosed with AD using PCR, RT-PCR, culture, electron microscopic and immunohistochemical analysis recently has been reported.1 We conducted a pilot study to confirm these observations. Brain samples, from AD cases (n = 9, including parahippocampal gyrus, entorhinal cortex, and temporal cortex) and non-AD cases (n = 2, temporal cortex and hippocampus) were examined as a blind panel using PCR and immunohistochemistry. Immunohistochemistry (figure) was performed on impression slides taken from the frozen brain samples using a C. pneumoniae –specific monoclonal antibody (DAKO). Nested PCR procedures were performed using sets of primers specific for C. pneumoniae , namely the 76-kd protein gene1 and the …

Introduction Treatment options for children with HIV-1 are limited. We aimed to compare activity and safety of three dualnucleoside analogue reverse-transcriptase inhibitor (NRTI) regimens with or without a protease inhibitor in previously untreated children with HIV-1. Methods In our multicentre trial, we randomly assigned 36 children to zidovudine and lamivudine, 45 to zidovudine and abacavir, and 47 to lamivudine and abacavir. Children who were symptomfree (n=55) were also randomly assigned to receive nelfinavir or placebo. Children with more advanced disease received open-label nelfinavir (73). Primary endpoints were change in plasma HIV-1 RNA at 24 and 48 weeks for the NRTI comparison and occurrence of serious adverse events for both randomised comparisons. Analyses were by intention to treat. Findings Children had a median CD4 percentage of 22% (IQR 15–29) and a mean HIV-1 RNA concentration of 5·0 log copies/mL (SD 0·8). One child was lost to follow-up and one died of sepsis. At 48 weeks, in the zidovudine/lamivudine, zidovudine/abacavir, and lamivudine/abacavir groups, mean HIV-1 RNA had decreased by 1·71, 2·19, and 2·63 log copies/mL, respectively (estimated in absence of nelfinavir) (p=0·02 after adjustment for baseline factors). One child had a hypersensitivity reaction to abacavir; and three with possible reactions stopped abacavir. There were 24 serious adverse events—six in the symptom-free children (all on nelfinavir), but none were attributed to nelfinavir. Interpretation Regimens containing abacavir were more effective than zidovudine/lamivudine. Such regimens could be combined with protease inhibitors and non-nucleoside reverse transcriptase inhibitors for safe and effective treatment of previously untreated children with HIV-1.

To determine the prevalence of genital Chlamydia trachomatis infection and risk factors in women attending family planning, gynaecology, and sexually transmitted disease (STD) clinics in Jamaica.Endocervical specimens from 645 women including 238 family planning, 170 gynaecology, and 237 STD clinic attendees were examined for C trachomatis using a direct fluorescence assay (DFA) and culture. Investigations were carried out for the presence of other STD pathogens and demographic, behavioural, historical, and clinical data recorded for each participant.The prevalence of C trachomatis infection was 35%, 47%, and 55% in family planning, gynaecology, and STD clinic clients, respectively. The performance of the DFA was comparable to that of culture in screening for C trachomatis. Logistic regression analysis revealed that the independent risk factors for C trachomatis infection were non-barrier contraceptive methods in family planning clients (OR = 2.1; 95% confidence interval (CI) = 1.2-3.9; p = 0.0110), cervical ectopy in gynaecology clients (OR = 3.9; 95% CI = 1.4-10.6; p = 0.0076) and concomitant Trichomonas vaginalis infection in STD clients (OR = 3.5; 95% CI = 1.8-6.8; p = 0.003). Age, number of sex partners, and reason for visit were not identified as risk factors for C trachomatis infection.Consistently high prevalence of C trachomatis infection occurs in Jamaican women. Universal screening or presumptive treatment should be evaluated as prevention and control measures for C trachomatis infection in this population where all women appear to be at risk.

In the B19 VP2 molecule an immunodominant heptapeptide epitope has been detected, recently for which IgG antibodies are synthesized exclusively in the acute phase of B19 infection. Using this acute-phase-specific epitope (KYVTGIN) a 2(nd)-generation epitope-type EIA was developed, which compares serum IgG activity for native VP2 capsids exhibiting conformational VP2 epitopes with IgG activity for the KYVTGIN epitope. In this study the diagnostic performance (clinical sensitivity and specificity) of the 1st and 2nd-generation epitope-type EIAs and of a peptide-based EIA utilising as antigen the KYVTGIN epitope alone was assessed in comparison with various high-quality IgM- and IgG- based B19 assays. Serum samples from 489 patients with B19-related symptoms and asymptomatic controls from three countries were studied. Among 323 patients with B19-IgG, 20% were diagnosed as acute infection, 73% had past immunity and 7% were not classified due to contradictory results among the different assays. The unclassified samples were explored for viral strain diversity by PCR and DNA sequencing but all sequences obtained were B19-like with variance of only a few per cent. The 2nd-generation epitope-type EIA had a diagnostic sensitivity of 98% and a diagnostic specificity of 94%. In combination with conventional approaches, the epitope-type assays increase greatly the accuracy of B19 serodiagnosis.

An outbreak of gastroenteritis followed a meal in a large hotel during which one of the diners vomited. The clinical features of the illness suggested Norwalk-like virus (NLV, small round structured virus) infection, and this was confirmed by electron microscopy and reverse transcriptase polymerase chain reaction (RT–PCR) of stool samples. Further characterization of the virus by nucleotide sequence analysis of the PCR amplicons revealed identical strains in all the affected individuals. The foods served at the meal could not be demonstrated to be the cause of the outbreak. Analysis of attack rates by dining table showed an inverse relationship with the distance from the person who vomited. No one eating in a separate restaurant reported illness. Transmission from person-to-person or direct contamination of food seems unlikely in this outbreak. However, the findings are consistent with airborne spread of NLV with infection by inhalation with subsequent ingestion of virus particles.

Small round structured viruses (SRSVs) are the major cause of outbreaks of gastroenteritis in the UK. Diagnosis is problematic due to insensitive electron microscopy (EM) or technically demanding reverse transcription polymerase chain reaction (RT-PCR) techniques. We have studied outbreaks of non-bacterial gastroenteritis using an EIA based upon recombinant capsid protein from the currently prevalent circulating strain of SRSV (Lordsdale Genotype II) and compared its performance against EM and RT-PCR assays. Faecal specimens sent to the Bristol Public Health Laboratory for outbreak investigation from December 1996 to December 1997 were applied retrospectively to the SRSV EIA and results compared with the routine EM and RT-PCR that had been carried out prospectively. Overall, the three tests identified SRSVs in specimens from 70% of the outbreaks (213/305) investigated. Of the 213 total positive outbreaks, the EIA identified 71%, that compared favourably with EM (63%) and RT-PCR (84%). The Lordsdale Genotype II SRSV EIA provides a simple cost-effective assay that will for the first time make detection of currently circulating SRSV strains associated with UK outbreaks available to all routine laboratories. The EIA format makes the assay widely applicable to non-specialist laboratories, unlike the RT-PCR assay, and the improved sensitivity over EM will allow successful screening of UK outbreaks alongside commercial EIAs currently available for adenovirus, astrovirus and rotavirus. Furthermore, the assay will allow rapid identification of emerging SRSV strains.

Respiratory syncytial virus (RSV) is known to cause acute lung injury in the immunocompromised host, especially recipients of bone marrow allografts. Specific prognostic factors for the development of severe life-threatening disease remain to be identified as does the optimum treatment of established disease. Over a 5-year period the incidence and outcome of RSV in BMT recipients was analysed retrospectively. Prognostic factors assessed included type of transplant, engraftment status at the time of infection, the presence of lower respiratory tract disease, viral genotype and treatment received. During the study period, 26 of 336 (6.3%) allogeneic stem-cell recipients were identified as having RSV. Five patients (19.2%) died as a direct result of RSV. One patient died secondary to an intracranial bleed with concomitant RSV. There were four patients with graft failure (two primary and two secondary) attributable to the presence of RSV, two of whom subsequently died of infections related to prolonged myelosuppression. The presence of lower respiratory tract infection and a poor overall outcome was the only statistically significant association. Unrelated donor transplants and AML as the underlying disease appeared to be associated with a poorer outcome. Engraftment status, viral genotype and RSV treatment received did not correlate with outcome. We conclude that future studies are required to identify early sensitive and reproducible prognostic factors of RSV in the immunocompromised host. The roles of intravenous and nebulised ribavirin need to be clarified by prospective controlled trials.

Southampton virus (SV) and Lordsdale viruses (LV) are small round structured viruses characterised recently and belong to two separate genogroups. The capsid genes of these viruses were expressed in insect cells using recombinant baculoviruses. Both SV (genogroup 1) and LV (genogroup 2) capsid proteins self-assembled to form virus-like particles (VLPs). The VLPs were used in a standard enzyme-linked immunosorbent assay (ELISA) to screen for antibodies to SV and LV in 1,729 age-stratified human sera collected in Verona, Italy between January and November 1996. SV VLPs were labile compared with LV VLPs. There was a large difference in the prevalence of SV (28.7%) compared with LV (91.2%). However, presentation of SV VLPs using chicken egg yolk antibody-coated wells (IgY capture ELISA) with a subset of serum samples from patients (0-19 years) increased the number of positive sera significantly (50.5%), indicating that SV antigen integrity is an important factor in the assay. Recent reverse transcription-polymerase chain reaction (RT-PCR) studies have shown that LV is circulating currently and analysis of IgY capture ELISA data showed greater reactivity for LV than SV, reflecting a genuinely lower rate of recent infection by this genogroup 1 virus.

The largest outbreak of the zoonotic disease Q fever recorded in the United Kingdom (UK) occurred in Birmingham in 1989. One hundred and forty-seven cases were identified, 125 of whom were males, and 130 of whom were between 16 and 64 years of age. Fewer cases of Asian ethnic origin were observed than expected (p0.01), and more smokers (p0.005). A case control study (26 cases and 52 matched controls) produced no evidence that direct contact with animals or animal products had caused the outbreak. The epidemic curve suggested a point source exposure in the week beginning 10 April. The home addresses of cases were clustered in a rectangle 11 miles (18.3 km) north/south by 4 miles (6.7 km) east/ west, and attack rates became lower towards the north. Directly south of this area were farms engaged in outdoor lambing and calving, a potent source of coxiella spores. A retrospective computerised analysis showed that the geographical distribution of cases was associated with a source in this area (p0.00001). On 11 April, unusual southerly gales of up to 78 mph (130 km/h) were recorded. The probable cause of the outbreak was windborne spread of coxiella spores from farmland to the conurbation.

Recent reports suggest an increased incidence of cytomegalovirus (CMV) infection in recipients of unrelated donor (UD) bone marrow transplantation (BMT). In this study we have collated the incidence of CMV infection and disease in sequential UD (n = 119) and related donor (RD; n = 79) BMT performed in a single institution over a 7-year period. Low-risk patients (CMV seronegative recipient and donor) accounted for 51% of UD BMT (n = 61) and 62% of RD BMT (n=49), with CMV excretion documented in one RD BMT only. The remaining high-risk patients received identical prophylaxis regimens with aciclovir and intravenous immunoglobulin (IVIG). Two groups consisting of 58 UD BMT (median age 9.0 years, range 0.7-45.3 years) and 30 RD BMT (median age 13.6 years. range 1.6-47.6 years) were analysed. CMV reactivation/re-infection was documented in 15 UD BMT (26%) and 10 RD BMT (33%) (P = 0.72), and CMV disease in four UD BMT (8%) and four RD BMT (13%) (P = 0.533). In this series the risk of CMV excretion and disease following UD BMT was similar to that following RD BMT.

Data from the national surveillance scheme for general outbreaks of intestinal disease, and the national laboratory reporting scheme were used to describe the epidemiology of small round structured virus (SRSV) infections in England and Wales. Between 1990 and 1995, there were 7492 laboratory reports of SRSV. Rates of reported illness were highest among infants, young children and the elderly. During 1992–5, some 707 SRSV outbreaks were reported. Outbreaks in hospital wards and residential facilities for the elderly accounted for 76% of the total, and annual numbers increased more than sixfold over the study period. There were wide regional variations in the numbers of SRSV outbreaks and laboratory reports. Both sporadic cases and outbreaks in the community are likely to be underestimated, but these passive surveillance systems provide an insight into the burden of SRSV infection among the institutionalized elderly.

Centralisation of viral diagnostic services offers the potential for cost saving in laboratories, but incurs costs for transporting specimens. In a trial of 326 paired specimens, isolation rates of viruses sent by overnight post and a more expensive same-day courier service were similar.

The gene coding for the major inner capsid protein VP6 of human group C rotavirus was cloned into baculovirus using the pBlueBac2 vector and expressed in insect cells. When cultured in High Five cells, VP6 was expressed at a high level and exported to the cell culture medium. Purified VP6 was used to immunise rabbits. Hyperimmune rabbit serum, which reacted with native human group C rotavirus in infected cells, was used to develop and optimise an EIA for the detection of antibodies to group C rotavirus using the recombinant VP6 as a source of antigen. In a local epidemiological survey of 1000 sera grouped by age, an average of 43% of samples were found to have antibodies to human group C rotavirus with the highest proportion (66%) in the 71-75 year age group. In comparison, 97% of adults and 85% of children had antibodies to recombinant VP6 from the bovine RF strain of group A rotavirus. These results suggest that infection with human group C rotavirus is a common occurrence despite the apparent rarity of reports of human group C rotavirus in clinical samples from patients with gastroenteritis.

Genetic typing of small round structured viruses (SRSVs) by reverse transcription-polymerase chain reaction (RT-PCR) and sequencing has been confined to analysis of the RNA polymerase because of the considerable genome variability outside of this region. To provide capsid sequence data for epidemiological studies and outbreak investigations, a broadly reactive capsid PCR was developed using two sets of degenerate, inosine-containing primers. Primer pairs Capla/Caplb and Caplla/Capllb specifically amplify a 223-bp region of the SRSV capsid open reading frame from SRSV genetic groups I and II, respectively. The capsid PCR was used to investigate SRSVs from nine UK outbreaks of gastroenteritis occurring between 1992 and 1995. Differential amplification by the primer pairs suggested that three strains belonged to genetic group I and six to genetic group II. The capsid amino acid sequences of the group I strains were 75.9% to 79.3% identical with Sot/91/UK (group I), while those of the group II strains were 75.9% to 98.3% identical with Bri/93/UK (group II). Phylogenetic comparison of the capsid region from the outbreak strains and 13 previously characterised SRSVs revealed clusters of strains closely related to Bri/93/UK and Tor/77/C within genetic group II. With the exception of some Bri/93/UK-like strains, there was no correlation between capsid sequence and the geographical origin of SRSVs. UK strains were found with greater than 90% capsid sequence identity to SRSVs from various locations worldwide including Australia (Cam/94/A), Canada (Tor/77/C), Hawaii (Haw/71/US), and Saudi Arabia (DSV395/90/SA) together with group I (B447/92/UK) and group II (Yat/94/UK) strains that were genetically distinct from known SRSV capsids. Three SRSVs very closely related to Bri/93/UK were from recent UK hospital outbreaks. These Bri/93/UK-like strains appear to be prevalent in the UK.

An enteric calicivirus showing the classic cup-shaped surface morphology was identified in a stool sample obtained from a child with symptoms of acute gastroenteritis (Portishead virus, PHV). Genomic RNA was extracted directly from the PHV stool sample and amplified by RT-PCR using primers based on the Manchester isolate of HuCV. The 3' terminus of the cDNA was defined by homopolymer tailing with dATP and revealed an additional 165 nucleotides suggesting that the previously determined Manchester HuCV (MV) genome sequence was incomplete. Homopolymer tailing of MV cDNA primed using sequence data from the 5' terminus of PHV allowed extension of the MV genome by a further 165 nucleotides thereby increasing the overall genome length to 7431 nucleotides and resulting in an additional 72 amino acids at the N-terminus of the polyprotein. A conserved sequence motif typical of other caliciviruses was also identified at the extreme 5'-terminus of the genome.

Outbreaks of foodborne viral gastroenteritis in England and Wales from 1992 to 1994 have been analysed using data from the national surveillance scheme for general outbreaks of infectious intestinal disease. The cause was virologically confirmed for 389 (31%) of the 1280 outbreaks for which a minimum set of data were collected. Forty-seven of the 389 were attributed to foodborne transmission, 41 of which were caused by small round structured viruses (SRSV). An infected food handler was suspected to be a contributing factor in 14 and the consumption of oysters in eight of these 41 foodborne SRSV outbreaks. No seasonal pattern emerged. The highest incidences occurred in Wales, West Midlands, and South Western regional health authorities. The annual rate of outbreaks did not increase during the three year period (Chi square for linear trend 0.6; p = 0.4). Much remains to be discovered about the epidemiology of foodborne viruses, and outbreaks present an opportunity to enhance our knowledge. As molecular diagnostic techniques become routinely available, it is likely that the role of viruses in foodborne outbreaks will be increasingly recognised.

Twenty-eight outbreaks of infectious intestinal disease, reported as being transmitted mainly by the person to person route, were identified in association with retail catering premises, such as hotels, restaurants, and public houses, in England and Wales between 1992 and 1994. Five thousand and forty-eight people were at risk in these outbreaks and 1234 were affected. Most of the outbreaks (over 90%) occurred in hotels. Small round structured viruses were the most commonly detected pathogens. Diarrhoea and vomiting were common symptoms and most of the outbreaks occurred in the summer months. Control measures to contain infectious individuals and improved hygiene measures are necessary to contain such outbreaks.

A case of disseminated adenovirus type 32 infection causing severe hepatitis, gastrointestinal ulceration and also with respiratory involvement is reported in a bone marrow transplant recipient. Typical viral inclusions were seen in the postmortem histological sections and adenovirus infection was confirmed using in situ hybridisation and isolation of adenovirus type 32 from separate organs at necropsy. This is the first case in which adenovirus 32 was the cause of fatal disseminated disease in a bone marrow transplant recipient.

A cDNA copy of the third genomic RNA segment of a noncultivatable human group C rotavirus (Bristol) was generated by single primer amplification. Human group C rotavirus genome segment 3 contains 2283 bp and encodes the VP4 gene with an open reading frame of 2232 nucleotides (744 amino acids) starting at nucleotide 21 and terminating at nucleotide 2251. PCR primers designed from the 5' and 3' terminal sequences of the C/Bristol VP4 gene were used to amplify the corresponding VP4 gene of a human group C rotavirus from Belem, Brazil. Nucleotide sequence comparisons of the Bristol and Belem VP4 genes revealed 45 differences of which only 6 were predicted to give amino acid changes. Alignment of the two human VP4 sequences with the prototype porcine group C/Cowden rotavirus VP4 showed only 71.2% nucleotide sequence identity. Protein sequence alignments showed that the human group C rotavirus VP4 sequences were 8 amino acids longer than the porcine VP4 sequence with an insertion of 6 amino acids, 252NSKLGD257 adjacent to the proposed proteolytic cleavage region (amino acids 231-250). The large overall number of differences between the human and porcine VP4 sequences strongly suggested that the porcine C/Cowden isolate may belong to a different group C rotavirus P "serotype." In contrast the very close similarity of the VP4 sequences of the UK and Brazilian group C rotaviruses support the hypothesis that these human isolates originate from a recent common ancestor.

Small round-structured viruses (SRSVs), also known as Norwalk or Norwalk-like viruses, are the major worldwide cause of acute, epidemic nonbacterial gastroenteritis in humans. These viruses, which contain a single-stranded RNA genome, have remained refractory to molecular characterization because of the small amounts of virus in clinical samples and the absence of an animal model and an in vitro culture system. The complete genomic nucleotide sequence of an SRSV, Southampton virus, was determined. The 7696-nucleotide RNA genome encodes three open reading frames whose sequences and organization strongly support proposals that SRVSs are members of the Caliciviridae.