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Featured researches published by Tom Nichols.


Sexually Transmitted Infections | 2007

Incidence and reinfection rates of genital chlamydial infection among women aged 16–24 years attending general practice, family planning and genitourinary medicine clinics in England: a prospective cohort study by the Chlamydia Recall Study Advisory Group

D Scott LaMontagne; Kathleen Baster; Lynsey Emmett; Tom Nichols; Sarah Randall; Louise McLean; Paula Meredith; V Harindra; J M Tobin; Gillian S Underhill; W Graham Hewitt; Jennifer Hopwood; Toni Gleave; A K Ghosh; Harry Mallinson; Alisha R Davies; Gwenda Hughes; Kevin A. Fenton

Background: In England, screening for genital chlamydial infection has begun; however, screening frequency for women is not yet determined. Aim: To measure chlamydia incidence and reinfection rates among young women to suggest screening intervals. Methods: An 18-month prospective cohort study of women aged 16–24 years recruited from general practices, family planning clinics and genitourinary medicine (GUM) clinics: baseline-negative women followed for incidence and baseline-positive women for reinfection; urine tested every 6 months via nucleic acid amplification; and behavioural data collected. Extra test and questionnaire completed 3 months after initial positive test. Factors associated with infection and reinfection investigated using Cox regression stratified by healthcare setting of recruitment. Results: Chlamydia incidence was mean (95% CI) 4.9 (2.7 to 8.8) per 100 person-years (py) among women recruited from general practices, 6.4 (4.2 to 9.8) from family planning clinics and 10.6 (7.4 to 15.2) from GUM clinics. Incidence was associated with young age, history of chlamydial infection and acquisition of new sexual partners. If recently acquiring new partners, condom use at last sexual intercourse was independently associated with lower incidence. Chlamydia reinfection was mean (95% CI) 29.9 (19.7 to 45.4) per 100/person-year from general practices, 22.3 (15.6 to 31.8) from family planning clinics and 21.1 (14.3 to 30.9) from GUM clinics. Factors independently associated with higher reinfection rates were acquisition of new partners and failure to treat all partners. Conclusions: Sexual behaviours determined incidence and reinfection, regardless of healthcare setting. Our results suggest annual screening of women aged 16–24 years who are chlamydia negative, or sooner if partner change occurs. Rescreening chlamydia-positive women within 6 months of baseline infection may be sensible, especially if partner change occurs or all partners are not treated.


Emerging Infectious Diseases | 2002

Trends in Fluoroquinolone (Ciprofloxacin) Resistance in Enterobacteriaceae from Bacteremias, England and Wales, 1990–1999

David M. Livermore; Dorothy James; Mark Reacher; Catriona Graham; Tom Nichols; Peter Stephens; Alan P. Johnson; Robert George

The Public Health Laboratory Service receives antibiotic susceptibility data for bacteria from bloodstream infections from most hospitals in England and Wales. These data were used to ascertain resistance trends to ciprofloxacin from 1990 through 1999 for the most prevalent gram-negative agents: Escherichia coli, Klebsiella spp., Enterobacter spp., and Proteus mirabilis. Significant increases in resistance were observed for all four species groups. For E. coli, ciprofloxacin resistance rose from 0.8% in 1990 to 3.7% in 1999 and became widely scattered among reporting hospitals. The prevalence of resistance in Klebsiella spp. rose from 3.5% in 1990, to 9.5% in 1996 and 7.1% in 1999, while that in Enterobacter spp. rose from 2.1% in 1990 to 10.5% in 1996 and 10.9% in 1999. For both Klebsiella and Enterobacter spp., most resistance was localized in a few centers. Resistance was infrequent and scattered in P. mirabilis, but reached a prevalence of 3.3% in 1999.


Journal of Antimicrobial Chemotherapy | 2010

Cephalosporin MIC creep among gonococci: time for a pharmacodynamic rethink?

Stephanie A. Chisholm; Johan W. Mouton; David A. Lewis; Tom Nichols; C Ison; David M. Livermore

BACKGROUND Gonorrhoea has been among the easiest infections to cure with antibiotics. Nevertheless, emerging resistance has driven repeated treatment shifts. Decreased cephalosporin susceptibility is now being reported. We examined cephalosporin MIC trends for Neisseria gonorrhoeae in the UK and undertook pharmacodynamic analyses to predict efficacy against strains with raised MICs. METHODS Neisseria gonorrhoeae isolates were collected annually in a structured surveillance from 26 genitourinary medicine clinics in England and Wales. MICs were determined by agar dilution and confirmed by Etests. Pharmacodynamic modelling was performed for cefixime and ceftriaxone with Monte Carlo simulations. RESULTS There was a progressive emergence of small numbers of gonococci with cephalosporin MICs of 0.125-0.25 mg/L; these were not seen before 2005 but, for ceftriaxone and cefixime, respectively, accounted for 0.4% (95% confidence interval 0.2%-1.1%) and 2.8% (1.6%-4.8%) of the 1253 isolates collected in 2008; such MICs are 16-64 times the modal values for the species. Pharmacodynamic analysis was complicated by evidence that cephalosporins need a longer period with the free drug level above MIC than the 7-10 h required for penicillin G; nevertheless, pharmacodynamic analyses predict that failures with the standard 400 mg cefixime po and 250 mg ceftriaxone im regimens become likely around the present MIC maxima. CONCLUSIONS Gonococci with ceftriaxone and cefixime MICs of 0.125-0.25 mg/L are accumulating in the UK. These MICs lie on the edge of likely responsiveness to current regimens, which need review. Possible responses include: (i) higher cephalosporin doses; (ii) multidose cephalosporin regimens; (iii) multidrug regimens; (iv) microbiologically directed treatment; or, in the future, (v) drug cycling. The practicalities of these approaches are discussed.


The Lancet | 2002

W135 meningococcal disease in England and Wales associated with Hajj 2000 and 2001.

Susan Hahné; Steve J. Gray; Jean Francois Aguilera; Natasha S. Crowcroft; Tom Nichols; Edward B. Kaczmarski; Mary Ramsay

An outbreak of W135 meningococcal disease was seen in 2000 and 2001 among pilgrims returning from Saudi Arabia and their contacts. The Public Health Laboratory Service set up enhanced surveillance to monitor spread and virulence of the outbreak strain, and to collect data on case characteristics. The number of cases reported from England and Wales in 2001 was similar to the number reported during 2000, despite a change in the recommendation for pilgrims to receive quadrivalent vaccine (against serogroup A, C, W135, and Y) instead of the A/C vaccine recommended in 2000. Both the recommendation and vaccine were not available until January, 2001, and coverage among pilgrims to the Hajj 2001 was low. The case--fatality ratio was high, and sustained transmission of the virulent outbreak strain was seen. Current control policies, both in primary and secondary prevention, might need better implementation.


The Lancet | 2003

Ciprofloxacin resistance in Neisseria gonorrhoeae in England and Wales in 2002

Kevin A. Fenton; C A Ison; Alan P. Johnson; Elizabeth Rudd; Iona M. C. Martin; Tom Nichols; David M. Livermore; Mehnam Soltani

The Gonococcal Resistance to Antimicrobials Surveillance Programme (GRASP) monitors trends in antimicrobial resistance in consecutive gonococcal isolates from 26 genitourinary medicine clinics in England and Wales. In 2002, 2204 gonococcal isolates were tested, and the overall prevalence of ciprofloxacin resistance (minimum inhibitory concentration > or =1 mg/L) was 9.8%, compared with 3.1% in 2001 and 2.1% in 2000. Between 2001 and 2002, prevalence of ciprofloxacin resistance increased two to three-fold, irrespective of recent sexual contact overseas, sex, or residence within or outside of London. These findings suggest that national and local treatment guidelines need to be reviewed urgently.


BMJ | 2008

Body piercing in England: a survey of piercing at sites other than earlobe

Angie Bone; Fortune Ncube; Tom Nichols; Norman Noah

Objectives To estimate the prevalence of body piercing, other than of earlobes, in the general adult population in England, and to describe the distribution of body piercing by age group, sex, social class, anatomical site, and who performed the piercings. To estimate the proportion of piercings that resulted in complications and the proportion of piercings that resulted in professional help being sought after the piercing. Design Cross sectional household survey. Setting All regions of England 2005. Participants 10 503 adults aged 16 and over identified with a two stage selection process: random selection of geographical areas and filling predefined quotas of individuals. Results weighted to reflect the national demographic profile of adults aged 16 and over. Main outcome measures Estimates of the prevalence of body piercing overall and by age group, sex, and anatomical site. Estimates, in those aged 16-24, of the proportion of piercings associated with complications and the seeking of professional help. Results The prevalence of body piercing was 1049/10 503 (10%, 95% confidence interval 9.4% to 10.6%). Body piercing was more common in women than in men and in younger age groups. Nearly half the women aged 16-24 reported having had a piercing (305/659, 46.2%, 42.0% to 50.5%). Of the 754 piercings in those aged 16-24, complications were reported with 233 (31.0%, 26.8% to 35.5%); professional help was sought with 115 (15.2%, 11.8% to 19.5%); and hospital admission was required with seven (0.9%, 0.3% to 3.2%). Conclusions Body piercing is common in adults in England, particularly in young women. Problems are common and the assistance of health services is often required. Though serious complications requiring admission to hospital seem uncommon, the popularity of the practice might place a substantial burden on health services.


Journal of Antimicrobial Chemotherapy | 2010

The English antibiotic awareness campaigns: did they change the public's knowledge of and attitudes to antibiotic use?

Cliodna McNulty; Tom Nichols; Paul Boyle; Mark Woodhead; Peter Davey

OBJECTIVES To determine the effect of the 2008 English public antibiotic campaigns. METHODS English and Scottish (acting as controls) adults aged > or = 15 years were questioned face to face about their attitudes to and use of antibiotics, in January 2008 (1888) before and in January 2009 (1830) after the antibiotic campaigns. RESULTS Among English respondents, there was a small increase in recollection of campaign posters (2009 23.7% versus 2008 19.2%; P = 0.03), but this increase was only 2.3% higher in England than in Scotland. We did not detect any improvement in either England or Scotland, or any differences between England and Scotland in the understanding of the lack of benefit of antibiotics for coughs and colds, and we found no improvement in antibiotic use. We detected a significant increase in respondents retaining leftover antibiotics. Over 20% reported discussing antibiotics with their general practitioner (GP) or nurse in the year to January 2009. The offer of a delayed antibiotic prescription was reported significantly more often by English respondents (19% versus 8% Scottish in 2009; P = 0.01), and English respondents were advised to use other remedies for coughs and colds significantly more often in the year to January 2009 (12.7% in 2009 versus 7.4% in 2008; P < 0.001). CONCLUSIONS There is little evidence that the 2008 public antibiotic campaigns were effective. The use and visibility of future campaign materials needs auditing. A carefully planned approach that targets the public in GP waiting rooms and through clinicians in consultations may be a more effective way of improving prudent antibiotic use.


Emerging Infectious Diseases | 2003

Foot and mouth disease in livestock and reduced cryptosporidiosis in humans, England and Wales.

William J. Smerdon; Tom Nichols; Rachel M. Chalmers; Hilary Heine; Mark Reacher

During the 2001 epidemic of foot and mouth disease (FMD) in livestock in England and Wales, we discovered a corresponding decrease in laboratory reports of cryptosporidiosis in humans. Using a regression model of laboratory reports of cryptosporidiosis, we found an estimated 35% (95% confidence interval [CI] 20% to 47%) reduction in reports during the weeks spanning the period from the first and last cases of FMD. The largest reduction occurred in northwest England, where the estimated decrease was 63% (95% CI 31% to 80%). Genotyping a subgroup of human isolates suggested that the proportion of Cryptosporidium genotype 2 strain (animal and human) was lower during the weeks of the FMD epidemic in 2001 compared with the same weeks in 2000. Our observations are consistent with livestock making a substantial contribution to Cryptosporidium infection in humans in England and Wales; our findings have implications for agriculture, visitors to rural areas, water companies, and regulators.


Journal of Antimicrobial Chemotherapy | 2011

Emergence of a Neisseria gonorrhoeae clone showing decreased susceptibility to cefixime in England and Wales

Stephanie A. Chisholm; Sarah Alexander; Leah Desouza-Thomas; Elisabeth Maclure-Webster; John Anderson; Tom Nichols; Catherine M. Lowndes; C Ison; East Midlands; M. Minassian; L. Riddell; V. Weston; C. Bignell; M. Farrington; C. Carne; R. Mulla; T. Balachandran; B. Azadian; K. McLean; A. McOwan; F. Boag; D. Krahe; M. Nathan; M. Graver; M. Tenant-Flowers; R. Holliman; P. Hay; A. Jepson; L. Green; B. MacRae

OBJECTIVES The third-generation cephalosporins recommended in national guidelines are amongst the last remaining effective agents for treatment of gonorrhoea. This study characterizes gonococcal isolates with decreased cefixime susceptibility from England and Wales. METHODS A total of 96 isolates of Neisseria gonorrhoeae exhibiting cefixime MICs of ≥0.125 mg/L, either collected as part of the Gonococcal Resistance to Antimicrobials Surveillance Programme (GRASP) between 2005 and 2008 (54 from a total of 4649 isolates) or referred to the national reference laboratory in 2008 and 2009 (42 isolates), were tested for susceptibility to a range of antimicrobial agents and were typed using N. gonorrhoeae multiantigen sequence typing (NG-MAST). RESULTS All 96 isolates were also resistant to tetracycline (MIC ≥2 mg/L) and ciprofloxacin (MIC ≥16 mg/L) and 56% showed low-level chromosomal resistance to penicillin. Where data were available, the mean patient age was 31 years, and 88% (83/94) of patients were men. Isolates referred through GRASP were predominantly from men who have sex with men (MSM; 29/44, 66%) and from patients of white British ethnicity (25/43, 58%). The majority of isolates belonged either to sequence type (ST) 1407 (71/96, 74%) or to a highly related ST that shares the tpbB allele (allele 110), but with a different por allele (20/96, 21%). ST1407 was found in both MSM (22/29, 76%) and heterosexual patients (12/15, 80%) and among all eight isolates from patients reporting sex abroad. CONCLUSIONS The emergence of a clonal group of gonococci showing decreased susceptibility to cefixime in England and Wales highlights the need for continued surveillance.


Sexually Transmitted Diseases | 2011

Prevalence of human papillomavirus antibodies in males and females in England.

Sarika Desai; Ruth Chapman; Mark Jit; Tom Nichols; Ray Borrow; Michael Wilding; Christina Linford; Catherine M Lowndes; Anthony Nardone; Richard Pebody; Kate Soldan

Background: Most studies of human papillomavirus (HPV) epidemiology have employed DNA testing, which measures current infections. Serum antibodies offer a longer-term marker of infection in individuals who seroconvert and can therefore provide additional information about the exposure of populations to HPV. Methods: Sera from a population-based sample of males and females aged 10 to 49 years, in England, were tested for type-specific HPV antibodies using a multiplexed competitive Luminex assay and previously defined cutoffs of 20, 16, 20, and 24 mMU mL−1 for HPV 6, 11, 16, and 18, respectively. Seropositivity and geometric mean titers of seropositives were analyzed by HPV type, gender, and age. Catalytic models were developed to explore potential effects of antibody waning over time and changing risk of infection by age-cohort. Results: Seroprevalence for HPV 6, 11, 16, and 18 was 16.4%, 5.7%, 14.7%, and 6.3%, respectively, among females and 7.6%, 2.2%, 5.0%, and 2.0%, respectively, among males. Seroprevalence in females was significantly higher than males (P < 0.001 for all types) and showed a decline in older ages that was not seen in males. There was no evidence of declining antibody titers with increasing age. Model results suggest that cohort effects mediated through changes in sexual behavior better explain the observed trend in seroprevalence than waning antibodies over time. Conclusions: Preimmunization HPV seroprevalence in England shows similar trends to reports from other developed countries. We find the lower seroprevalence in older females probably reflects changes in sexual behavior over the last few decades. This study provides baseline data to monitor the impact of the immunization programme.

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C Ison

Health Protection Agency

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Paul Boyle

University of St Andrews

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