PubMed Health⌕ Search

Biomedical subjects

N S Crowcroft

Publications and source records attributed to N S Crowcroft.

At least 37 records · Page 2Linked to original sources
PubMed2002

National enhanced surveillance of meningococcal disease in England, Wales and Northern Ireland, January 1999-June 2001.

Enhanced surveillance of meningococcal disease (ESMD) was implemented nationally across ten regions of England, Wales and Northern Ireland from 1 January 1999. It aims to deliver more sensitive surveillance than laboratory reporting by including clinically diagnosed but laboratory unconfirmed cases. Consultants in Communicable Disease Control (CsCDC) report all clinically diagnosed cases of meningococcal disease (MD) to the Regional Epidemiologist in the relevant regional unit of the Public Health Laboratory Service (PHLS) Communicable Disease Surveillance Centre (CDSC). These reports are reconciled with laboratory data from the PHLS Meningococcal Reference Unit and then forwarded to the national CDSC where further reconciliation with laboratory data takes place. In addition, CsCDC are asked to report any clusters of MD that occur. Between 1 January 1999 and 30 June 2001, 12,074 cases of MD were ascertained through ESMD. The majority (57%) were laboratory confirmed. The estimated incidence of MD fell between 1999 and 2001 from 9.2 to 8.0 per 100,000 population. Of laboratory confirmed cases, the number of cases of serogroups B and W135 increased and of serogroup C and of ungrouped meningococcal infection decreased. Variation between regions was considerable and deserves further investigation. Of 11,522 cases with a reported clinical diagnosis, 53.6% were diagnosed as septicaemia, 32.6% as meningitis, 12.5% as both septicaemia and meningitis, and 13% had other invasive MD. Between 1 January 1999 and 30 June 2001 698 deaths were reported, an overall case fatality rate (CFR) of 5.8%; 567 deaths were in confirmed cases and 131 probable (CFR 8.2% and 2.5%, respectively). CFR was higher in serogroup C (13.5%) than B (5.8%). No peak in serogroup C meningococcal infection occurred in the winter of 2000/1 and no clusters of serogroup C meningococcal infection were reported in the first half of 2001. ESMD provides information about the epidemiology of MD that is more complete than statutory notification and laboratory surveillance and is useful for evaluating the impact of the meningococcal serogroup C vaccination programme and of the other non-vaccine preventable serogroups.

Adolescent↗
PubMed2002

UK guidelines for use of erythromycin chemoprophylaxis in persons exposed to pertussis.

Pertussis is well controlled in the UK as a result of an effective vaccination programme. Nevertheless, the disease has not been eliminated, and cases still occur in the most vulnerable group of young infants. Erythromycin chemoprophylaxis has been advocated for use in contacts to prevent secondary cases but the evidence for its use is weak. These guidelines are based on a review of the evidence and aim to help clinicians make more rational decisions on the use of erythromycin chemoprophylaxis for pertussis. Erythromycin has well-established side effects and so its use should be limited to situations where it is likely to be of greatest benefit. If a clinically suspected or confirmed case of pertussis is identified who is also in household contact with someone at greatest risk from pertussis--young infants, especially neonates--then erythromycin chemoprophylaxis should be considered. The aim is to protect those at greatest risk from pertussis by offering chemoprophylaxis to them, to all their household contacts who are unimmunized and to contacts who are 5 years or older if they did not receive a pre-school pertussis booster (not given to those born before 1996 in the United Kingdom). There is no evidence of any benefit from chemoprophylaxis given more than 21 days from the date of onset of the primary case. Unimmunized or partially immunized cases and contacts should complete their course of vaccine.

Antibiotic Prophylaxis↗
PubMed2002

Deaths from pertussis are underestimated in England.

AIMS: To improve estimates of deaths from pertussis in England and to identify reasons for under ascertainment. METHODS: Comparison of deaths identified from enhanced laboratory pertussis surveillance, hospital episode statistics (HES), and Office for National Statistics (ONS) death registrations in England, 1994 to 1999. RESULTS: A total of 33 deaths were identified, 88% of infants less than 4 months old. There was overlap between all sources; 22 deaths were identified in the enhanced pertussis surveillance system, 18 in ONS mortality data, and nine in HES. Children who had died from pertussis without mention of pertussis on the death certificate were more likely to have been certified by coroners than those with mention of pertussis (p = 0.0005). Using capture-recapture analysis, the total number of deaths from pertussis in the five and a half year period is estimated to be 46 (95% CI 37 to 71), or around nine deaths per year. CONCLUSIONS: National mortality statistics significantly under estimate deaths from pertussis in England and are inadequate for monitoring the national immunisation programme. The largest number of deaths is identified through enhanced laboratory surveillance. Death registration systems should take into account available microbiological information to ensure that cause of death is accurately assigned.

Cause of Death↗
PubMed2002

Viral haemorrhagic fevers in Europe--effective control requires a co-ordinated response.

Viral haemorrhagic fevers (VHF) have attracted the attention of the medical world and general public for many reasons, some based in reality and more on misinformation. They are amongst the highest profile infections in the public mind, because they are thought to be highly infectious and to kill most of their victims in a dramatic way (1,2). To add to the intrigue, mysteries remain about the source of some of the viruses involved. They emerge and re-emerge in many countries, most recently Ebola in Uganda in 2000 (3) and Gabon in 2001/02 (4), and Congo Crimean Haemorrhagic Fever (CCHF) in Kosovo (5) and Pakistan in 2001 (6). Large outbreaks have affected populations in endemic areas, living mainly in inaccessible areas or refugee camps where living conditions are very difficult. Poorly resourced medical facilities have played a role in amplifying transmission and infection control measures have been difficult or virtually impossible to establish. These viruses are likely to remain a threat until the reservoir is identified and as long as endemic areas are afflicted with ecological change, poverty and social instability. Recent events since September 11 2001 remind us of their potential to be used as weapons, and that fear can present a risk to public health.

Communicable Disease Control↗
PubMed2002

Guidelines on the management of, and exposure to, rash illness in pregnancy (including consideration of relevant antibody screening programmes in pregnancy).

These guidelines, produced by the Public Health Laboratory Service (PHLS) aim to help decision making in the investigation and management of pregnant women who have 'a rash compatible with a systemic viral illness', or who have contact with a person with such an illness. They address particularly rubella, parvovirus B19, and varicella-zoster virus infection, but consider other infective causes of rash illness in the United Kingdom. The guidelines give the magnitude and degrees of risk to the fetus in terms of outcomes for the gestation at which maternal infection occurs. Recent changes in epidemiology and management lead to the following specific advice, which both updates and re-affirms established guidelines. All pregnant women with a non-vesicular rash illness should be investigated simultaneously for rubella and parvovirus B19 infection. All pregnant women who have had significant contact with a person suffering from a non-vesicular illness should be investigated for asymptomatic parvovirus B19 infection, and for asymptomatic rubella infection unless there is satisfactory evidence of past rubella infection (vaccine or natural infection). A significant contact is defined as being in the same room for over 15 minutes, or face-to-face contact. Specific investigation to detect asymptomatic rubella reinfection is not advised. It is essential to confirm by adequate laboratory investigation all cases of possible rubella and parvovirus B19 infection in pregnancy. Management of proven rubella in pregnancy should be based on established risks of adverse outcome. Women with proven parvovirus B19 infection in the first 20 weeks of pregnancy should be followed by regular, ultrasound scanning, and referred to Regional Units of Fetal Medicine if hydrops fetalis is detected. Parvovirus B19 antibody screening in pregnancy is not advised, and consensus has been reached on the procedures to be followed for rubella antibody screening, including the concentration of antibody that reflects past infection. Oral antiviral treatment (aciclovir) is advised with informed consent for pregnant women who present within 24 hours of onset of varicella. Referral to hospital and intravenous antiviral treatment is indicated for pregnant women with complications and/or risk factors, or whose illness continues for six days or more. Pregnant women exposed to varicella or herpes zoster can be reassured as to their protection if they themselves have a history of varicella or herpes zoster. If this history is uncertain or not known, susceptibility should be tested, and varicellazoster immunoglobulin (VZIG) offered to those found susceptible if within 10 days of first exposure. Infants whose mothers develop varicella 7 days before to 7 days after delivery should be given VZIG, and aciclovir if onset was 4 days before to 2 days after delivery.

Communicable Disease Control↗
PubMed2002

West Nile virus and the threat to the UK.

West Nile virus (WNV) is an RNA virus and a member of the Flaviviridae family. The recent geographical expansion of WNV into areas where no activity had been previously reported has been highlighted by the detection of WNV in North America. There is also a recent trend for more numerous and serious outbreaks in Eurasia. The main hosts are birds and the principle vectors are mosquitoes, usually of the genus Culex. Although most infected people do not become symptomatic, severe diseases such as encephalitis and, less commonly, aseptic meningitis may occur, more frequently in the elderly. The public can be protected by giving advice on the avoidance of mosquito bites and by the implementation of ecological surveillance and measures to reduce the mosquito population. While a few human cases have been identified in returning travellers, WNV has not been reported in any animal or bird in the UK. However, this may simply indicate that the diagnosis has not been sought. Potential avian hosts and mosquito vectors of WNV are present in the UK and birds migrate to the UK from areas of endemic WNV activity. However, the population density of mosquitoes is relatively low and therefore the risk of WNV being transmitted in the UK is thought to be low. We lack sufficient information on the ecology of the virus, and on mosquito populations, to accurately determine this risk. Clinicians are advised to consider WNV as a differential diagnosis, especially in patients over 50 years old with a clinical picture of viral encephalitis or aseptic meningitis presenting in the summer months.

Animals↗
PubMed2002

Enhanced surveillance scheme for suspected meningococcal disease in five regional health authorities in England: 1998.

Enhanced surveillance of meningococcal disease (ESMD) began in five English regions on 1st January 1998. The aims of the scheme were to obtain accurate incidence data and develop a robust surveillance system with which to monitor the impact of a new meningococcal serogroup C conjugate vaccine. During 1998, 2,314 suspected cases of meningococcal disease were identified. The majority (84%) was classified as invasive meningococcal disease, with infection of N. meningitidis confirmed in 66%. Sixteen per cent of suspected cases were subsequently given an alternative diagnosis. Age differences between those classified as meningococcal disease and those not, implied a higher index of suspicion of meningococcal disease in younger children. Regions with high rates of meningococcal disease were due to a higher rate of serogroup C. ESMD increased ascertainment of meningococcal disease and deaths. Cases were 34% greater than identified through statutory notifications, an additional 6.8% confirmed infections were identified than were reported to the PHLS Meningococcal Reference Unit (MRU) and deaths were 24% greater than death registrations. These data were used to inform the national meningococcal serogroup C conjugate vaccination programme in England and Wales. In 1999 ESMD was extended to all regions of England, Wales and Northern Ireland.

Adolescent↗
PubMed2002

Estimating the burden of serogroup C meningococcal disease in England and Wales.

In 1999 a new conjugate vaccine for serogroup C meningococcal disease was licensed for use in the UK. In order for an appropriate vaccination strategy to be developed the burden of serogroup C disease in England and Wales needed to be established. This was done using data from an enhanced surveillance scheme alongside routine laboratory reports and a total of 5,052 cases of serogroup C disease in England and Wales between 1993 and 1998 were estimated. Among these, an estimated 398 died and 1,767 were admitted to intensive care units (ITUs). The greatest burden of disease was in young children and teenagers. The current literature identified four studies reporting sequelae following serogroup C meningococcal disease. These provided estimates of sequelae in the range of 6.5% and 45% and presented some evidence of higher levels than occur following serogroup B meningococcal disease. This information was provided to the Joint Committee on Vaccination and Immunisation to inform policy to implement a serogroup C conjugate vaccination programme in the UK. The vaccination programme has since been justified by the dramatic reduction in serogroup C meningococcal cases.

Adolescent↗
PubMed2001

Guidelines for the control of hepatitis A virus infection.

The PHLS Advisory Committee on Vaccination and Immunisation, following a review of the evidence on control measures for preventing hepatitis A virus (HAV) infection and widespread consultation, has prepared the following guidelines. They include a description of the current epidemiology of HAV infection in England and Wales, where most individuals are now susceptible to HAV. HAV infection is uncommon, with around 1000 infections notified per year in England and Wales. Clusters occur in families and in settings where potential for faecal/oral spread is high, e.g. day care centres, nurseries, primary schools. Larger outbreaks have been recorded in men who have sex with men and injecting drug users. Personal hygiene remains the cornerstone of measures for preventing HAV infection and its spread. Those with haemophilia, hepatitis B or C virus infection or liver cirrhosis, intravenous drug users and men who have sex with men should be offered HAV vaccination as a preventive measure. HAV vaccine should be used for preventing secondary cases and outbreaks provided that patients are informed that the latest date the vaccine is most likely to be effective in preventing disease in contacts is probably 7 days from onset of illness in the primary case. Human normal immunoglobulin (HNIG) should be offered in addition or in preference to vaccine for contacts who are more than 7 days from onset of illness in the primary case, and for those at risk of adverse outcome of HAV infection. Individuals at particular risk of an adverse outcome to infection include those more than 50 years old, with liver cirrhosis of any cause, or with pre-existing hepatitis B or C virus infection. HAV vaccine should be used to prevent infection for travellers to countries where HAV infection is a risk. HNIG is no longer indicated for travellers. Children travelling to such countries should be offered vaccine from 5 years and consideration should be given to vaccinating those aged 1-4 years.

Adult↗
PubMed1999

Methicillin-resistant Staphylococcus aureus and antimicrobial use in Belgian hospitals.

OBJECTIVE: To investigate relationships between the incidence of methicillin-resistant Staphylococcus aureus (MRSA) and the use of different classes of antimicrobials in Belgian hospitals. DESIGN: Using Pearson correlation coefficients, the number of new nosocomial MRSA-colonized or -infected patients in the second half of 1994 and the first half of 1995 reported by the national MRSA surveillance program was compared with use of various antimicrobial classes as reported by the National Institute for Sickness and Disability Insurance. Relationships between different classes of antimicrobials were evaluated in a correlation matrix. MRSA incidence, antimicrobial use, and potential confounding factors were included in a multiple linear regression analysis. SETTING: 50 hospitals in Belgium. RESULTS: The use of a number of different classes of antimicrobials was interrelated. In the multivariate analysis, the incidence of nosocomial MRSA increased with increasing use of ceftazidime and cefsulodin (P=.0003), amoxicillin with clavulanic acid (P=.02), and quinolones (P=.005). No association was found between MRSA incidence and total antimicrobial use. CONCLUSIONS: The relationships between antimicrobial use and MRSA are complex. Interventions aimed at promoting more rational prescribing patterns should be supported by adequate experimental and epidemiological evidence. Advice for preventing and controlling MRSA has focused mainly on hygienic measures and precautions to avoid cross-transmission; the role of relieving antimicrobial pressure needs to be clarified.

Anti-Bacterial Agents↗
PubMed1999

Guidance for control of parvovirus B19 infection in healthcare settings and the community.

Interventions for parvovirus B19 infection need to balance the low risk of infection at a population level with the potential for serious adverse outcome for particular groups, notably the fetus, people with haemoglobinopathies and the immunocompromised. This guidance aims to assist the local decision-making process to be as evidence-based as the available evidence allows.

Adolescent↗
PubMed1999

Respiratory syncytial virus: an underestimated cause of respiratory infection, with prospects for a vaccine.

Respiratory syncytial virus (RSV) infects most people by the time they are 2 years old and reinfects throughout life. RSV is best recognised for causing bronchiolitis in infants--it is one of the most important respiratory pathogens in childhood in industrialised countries. The clinical manifestations of RSV infection in adults and elderly people, from upper respiratory tract infection to pneumonia, are less well known. Part of the burden of winter mortality in elderly people is attributable to RSV infection and it may be as important a cause of death as influenza. Recent advances in RSV vaccines have made RSV a more important topic for epidemiological research and surveillance. Basic research required before vaccine programmes can be developed includes describing the natural history of RSV infection in adults, quantifying the burden of disease attributable to RSV, and defining the best surveillance methods with which to evaluate different vaccination strategies.

Adult↗
PubMed1998

Epidemiology of Epstein-Barr virus infection in pre-adolescent children: application of a new salivary method in Edinburgh, Scotland.

STUDY OBJECTIVE: To describe the epidemiology of Epstein-Barr virus (EBV) among primary school children by testing saliva with a new EBV capsid antigen "G" antibody capture radioimmunoassay (GACRIA). DESIGN: A population based sample of 7 year old schoolchildren were followed up at age 11. SETTING: 30 randomly chosen primary schools in Edinburgh, Scotland. PARTICIPANTS: 552 schoolchildren. MEASUREMENTS: Data on risk factors for infection were collected by questionnaire at ages 7 and 11. Saliva samples collected at age 11 were examined by GACRIA for evidence of previous infection with EBV. For 102 subjects, a second salivary specimen collected approximately one month after the first sample was available for testing as a measure of the repeatability of the method. MAIN RESULTS: Unequivocal results were found in 91% of samples and the repeatability of the test was good (kappa = 0.71). Fifty six per cent of children had antibodies to EBV. In a logistic regression analysis, independent risk factors for infection were sharing a room (odds ratio 1.78, 1.14, 2.79), head of household's social class IV/V compared with I (odds ratio 2.87, 1.08, 7.34), and schools serving predominantly rented housing estates (odds ratio 2.3, 1.09, 4.84). CONCLUSION: This study is the first application of EBV viral capsid GACRIA to salivary samples. The method was successfully used to describe the epidemiology of EBV. In this study, characteristics of the home seemed to be more important than those of the school in determining the likelihood of infection with EBV.

Adult↗
PubMed1997

The social origins of infantile colic: questionnaire study covering 76,747 infants.

OBJECTIVE: To describe risk factors for infantile colic. DESIGN: Questionnaire administered by health visitors. SETTING: Sheffield. SUBJECTS: Mothers of 76,747 infants born between 1 August 1975 and 31 May 1988, interviewed when the infant was 1 month old. MAIN OUTCOME MEASURES: Reporting of infantile colic and its duration; weight of infant leeding, state of the home, socioeconomic characteristics of the parents, parents' age, and mother's parity. RESULTS: The odds of reporting infantile colic were increased with breast feeding (odds ratio of breast v bottle feeding 1.35 (95% confidence interval 1.28 to 1.43)), increasing parental age, lower parity, increasing parental age at leaving full time education, and more affluent homes and districts of residence. In a logistic regression analysis, mother's age and parity and socioeconomic factors remained the most important risk factors for the reporting of infantile colic (each P < 0.005), and the effect of breast feeding was attenuated (odds ratio of breast v bottle feeding 1.09 (1.02 to 1.15)). CONCLUSION: At a population level, dietary factors contribute little to mothers' reporting of infantile colic, and dietary change should not be the primary intervention.

Age Factors↗
PubMed1994

Cholera: current epidemiology.

Cholera remains an important cause of morbidity and mortality worldwide. Its epidemiology has changed in the 1990s, with the spread of the seventh pandemic to the western hemisphere and the emergence of a new serogroup, Vibrio cholerae O139. The spread of cholera may be rapid and unpredictable because of aeroplane travel, international shipping, and the migration of people due to war or political unrest. Increasing amounts of largely untreated faeces from growing human populations favour cholera's survival. Most of the world has inadequate sanitation, and future prospects are undermined by the impact of international debt on ailing economies. Furthermore, because cholera is difficult to eradicate from water it is likely to remain a serious threat to public health for some time. Progress is being made in the development of oral vaccines against V. cholerae O1 and serogroup O139.

Cholera↗