Neville Q. Verlander

Group B streptococcal disease in UK and Irish infants younger than 90 days

The incidence, morbidity, and mortality of group B streptococcal disease in the UK and Republic of Ireland are largely unknown. Between Feb 1, 2000, and Feb 28, 2001, we identified cases of invasive group B streptococcal disease in infants younger than 90 days through surveillance involving paediatricians, microbiologists, and parents. 568 cases were identified, equivalent to a total incidence of 0.72 per 1000 live-births (95% CI 0.66-0.78); the incidence for early-onset disease (n=377) was 0.48 per 1000 (0.43-0.53), and for late-onset disease (n=191) was 0.24 per 1000 (0.21-0.28). Risk factors were identifiable for 218 (58%) cases of early-onset disease. 53 infants died (overall 9.7%). We have established the minimum current burden of group B streptococcal disease in UK and Irish infants. This information will assist in the formulation of guidelines for prevention of this disease.

Sporadic Cryptosporidiosis Case- Control Study with Genotyping

Risk factors for Cryptosporidiosis in United Kingdom.

Health sequelae of human cryptosporidiosis in immunocompetent patients

BACKGROUND There have been no systematic studies following up the longer term health effects of cases of cryptosporidiosis for which genotype data exist. METHODS We report a follow-up study of cases of laboratory-confirmed cryptosporidiosis. Case patients were sent a postal questionnaire asking about a wide range of symptoms occurring within 2 months after their initial diagnosis, and control subjects were sent the questionnaire 2 months after they had been recruited to the original study. RESULTS Completed questionnaires were received from 235 case patients and 232 control subjects. For 111 of the case patients, the species of the infecting strain was known; 61 of these strains were Cryptosporidium hominis (human genotype), and 50 were Cryptosporidium parvum (bovine genotype). Forty percent of the case patients reported recurrence of intestinal symptoms after resolution of the acute stage of illness, irrespective of whether infection was with C. hominis or C. parvum. Reports of joint pain (odds ratio [OR], 2.8), eye pains (OR, 2.44), recurrent headache (OR, 2.10), dizzy spells (OR, 1.69), and fatigue (OR, 3.0) were significantly more common in case patients than in control subjects, but only in people who had experienced C. hominis infection. Joint symptoms experienced by case patients were of longer duration than those experienced by control subjects. CONCLUSIONS Our results confirm previous reports of a high rate of relapse of gastrointestinal symptoms following recovery from an acute episode of cryptosporidiosis and show that C. hominis but not C. parvum is associated with an increased risk of nonintestinal sequelae. This study demonstrates that the impact of cryptosporidiosis on public health extends beyond that of the acute diarrheal illness and can lead to significant health sequelae.

Clinical Severity of Clostridium difficile PCR Ribotype 027: A Case-Case Study

Background Clostridium difficile is a leading infectious cause of health care associated diarrhoea. Several industrialised countries have reported increased C. difficile infections and outbreaks, which have been attributed to the emergent PCR ribotype 027 strain. Methods and Findings We conducted a case-case study to compare severity of C. difficile disease for patients with 027 versus non-027 ribotypes. We retrospectively collected clinical information about 123/136 patients with C. difficile infections admitted to hospitals in the East of England region in 2006 and from whom stool isolates were cultured and ribotyped as part of an earlier national survey. We defined severe C. difficile disease as having one or more of shock, paralytic ileus, pseudo membranous colitis or toxic megacolon. Patient median age was 83 years old (range 3 to 98, interquartile range 75 to 89), 86% were prescribed antibiotics in the eight weeks before illness onset, 41% had ribotype 027 and 30-day all cause mortality during hospital admission was 21%. Severe disease occurred in 24% (95%CI 13% to 37%) and 17% (95%CI 9% to 27%) of patients with PCR ribotype 027 and non-027 ribotypes respectively. In a multivariable model, ribotype 027 was not associated with severe disease after adjusting for sex, discharge from hospital prior to 60 days of current admission, gastroenteritis on admission, number of initiator antibiotics for C. difficile disease, and hospital where the patient was admitted. Conclusions Our study found no evidence to support previous assertions that ribotype 027 is more virulent than other PCR ribotypes. This finding raises questions about the contribution of this strain to the recent increase in C. difficile disease throughout North America and Europe.

Rainfall and outbreaks of drinking water related disease and in England and Wales

A case-crossover study compared rainfall in the 4 weeks before drinking water related outbreaks with that in the five previous control years. This included public and private drinking water related outbreaks in England and Wales from 1910 to 1999. Of 111 outbreaks, 89 met inclusion criteria and the implicated pathogens included Giardia, Cryptosporidium, E. coli, S. Typhi, S. Paratyphi, Campylobacter and Streptobacillus moniliformis. Weather data was derived from the British Atmospheric Data Centre There was a significant association between excess cumulative rainfall in the previous 7 days and outbreaks (p=0.001). There was an excess of rainfall below 20 mm for the three weeks previous to this in outbreak compared to control weeks (p=0.002). Cumulative rainfall exceedances were associated with outbreak years. This study provides evidence that both low rainfall and heavy rain precede many drinking water outbreaks and assessing the health impacts of climate change should examine both.

Sporadic cryptosporidiosis, North Cumbria, England, 1996-2000.

Risk factors for sporadic cryptosporidiosis were determined in 152 patients and 466 unmatched controls who resided in two local government districts in North Cumbria, North West England, from March 1, 1996, to February 29, 2000. Risk was associated with the usual daily volume of cold unboiled tap water drunk (odds ratio [OR] 1.40, 95% confidence intervals [CI] 1.14 to 1.71 per pint consumed per day [p = 0.001]) and short visits to farms (OR 2.02, 95% CI 1.04 to 3.90, p = 0.04). Fifty-six (84%) of 67 fecal specimens from patients obtained from January 1, 1998, and February 29, 2000, were Cryptosporidium parvum genotype 2 (animal and human strain). Livestock fecal pollution of water sources appears to be the leading cause of human sporadic cryptosporidiosis in this population and shows the need for better protection of water catchments from livestock and improved drinking water treatment in this area of England.

Risk factors for toxoplasmosis in pregnant women in Kent, United Kingdom

The aim of this study was to establish the relative importance of various risk factors for toxoplasmosis in a United Kingdom antenatal population. Toxoplasma immune status was determined by an immunoassay and linked to a questionnaire exploring dietary and environmental exposure to toxoplasmosis. The overall seroprevalence found was 9.1% (172/1897). A significantly higher seroprevalence was associated with rural location of the childhood home, childhood home in Europe excluding the United Kingdom, feeding a dog raw meat and increased age. A non-significant higher prevalence of toxoplasmosis was observed in women who had lived with a cat or kitten as a child. In contrast to recent European studies only weak associations between diet and toxoplasmosis were found. Gardening activity was not associated with seropositivity but a non-significant lower seroprevalence was seen in gardeners who always wore gloves. This study confirms that toxoplasma prevalence in the United Kingdom has continued to decline since the 1960s. The increasing seroprevalence with age found in this study, highlights the continuing need to educate women of childbearing age about the risk factors for toxoplasmosis.

Group B streptococcal disease in infants: a case control study.

Objectives: To describe and quantify the maternal and neonatal factors associated with Group B streptococcus (GBS) disease in infants <90 days of age. Setting: Neonatal Units in London, Oxford, Portsmouth and Bristol. Patients: Cases were infants <90 days of age with invasive GBS disease diagnosed between 2000 and 2003, and controls were healthy infants born in the same hospital and in the same birth weight category. Main outcome measures: Demographic and clinical data on the mother, baby, birth and neonatal stay. Results: 138 cases and 305 controls were recruited. The majority of cases (74%) presented in the first week of life (early onset, EO); most on day 1 (89%). 65% of EO cases had one or more clinical risk factors (prematurity, prolonged rupture of membranes (PROM), known maternal GBS carriage, fever during labour). A multivariable logistic regression analysis found that the strongest independent associations with GBS disease were known maternal carriage of GBS (odds ratio (OR) 6.9), maternal infection in the peripartum period (OR 4.2) and maximum temperature in labour (OR 2.2 per °C). GBS disease was associated with twice the likelihood of PROM and fetal tachycardia (p = 0.05 and 0.07 respectively). EO cases had lower Apgar scores and were more likely to have respiratory distress and convulsions, and to require tube feeding than controls. They spent longer in hospital than controls, requiring longer stays at all levels of care. Conclusions: Independent of birth weight, a number of maternal, birth and neonatal factors are significantly associated with GBS disease. The management of babies with GBS disease results in an appreciable use of hospital resources.

The prevalence of urethral and rectal Mycoplasma genitalium and its associations in men who have sex with men attending a genitourinary medicine clinic

Objectives To determine the prevalence of rectal and urethral Mycoplasma genitalium (MG) in men who have sex with men (MSM) attending a genitourinary medicine clinic and to measure its associations with symptoms, clinical signs, sexual behaviour and concomitant sexually transmitted infections (STI). Methods MSM attending for STI screening were tested for MG using a real-time PCR assay that targets the MgPa gene. Data were collected on demographics, sexual behaviour, past STI history and clinical symptoms and signs. Results 849 first-void urine and rectal specimens were collected from 438 MSM. The overall prevalence of MG in MSM was 6.6% with first-void urine positivity of 2.7% and rectal positivity of 4.4%. MG was significantly associated with HIV positivity (OR 7.6, 95% CI 3.2 to 18.7, p<0.001) in contrast to Chlamydia trachomatis (OR 1.5, 95% CI 0.5 to 4.1, p=0.4) and Neisseria gonorrhoeae (OR 1.7, 95% CI 0.7 to 3.8, p=0.194). MG was more prevalent than C trachomatis (p=0.15) and N gonorrhoeae (p=0.02) in this subgroup of HIV-positive MSM. Urethral infection was associated with dysuria (p<0.001) but there was no association between rectal infection and anorectal symptoms or signs. Conclusion Rates of MG are much higher in HIV-positive MSM than HIV-negative MSM at both urethral and rectal sites, and MG is more prevalent in HIV-positive MSM than other bacterial STI. Although the subclinical nature of MG in the rectum questions its significance, the high prevalence seen at this site could be a potential source of onward urethral transmission. Future work should assess the need for appropriate screening and treatment of MG infection in MSM, particularly those with HIV infection and high-risk sexual behaviour.

Large outbreak of verocytotoxin-producing Escherichia coli O157 infection in visitors to a petting farm in South East England, 2009

SUMMARY In the summer of 2009, an outbreak of verocytotoxigenic Escherichia coli O157 (VTEC O157) was identified in visitors to a large petting farm in South East England. The peak attack rate was 6/1000 visitors, and highest in those aged <2 years (16/1000). We conducted a case-control study with associated microbiological investigations, on human, animal and environmental samples. We identified 93 cases; 65 primary, 13 secondary and 15 asymptomatic. Cases were more likely to have visited a specific barn, stayed for prolonged periods and be infrequent farm visitors. The causative organism was identified as VTEC O157 PT21/28 with the same VNTR profile as that isolated in faecal specimens from farm animals and the physical environment, mostly in the same barn. Contact with farm livestock, especially ruminants, should be urgently reviewed at the earliest suspicion of a farm-related VTEC O157 outbreak and appropriate risk management procedures implemented without delay.