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A Bosman

Publications and source records attributed to A Bosman.

At least 19 recordsLinked to original sources
PubMed2005

[Sharp increase of infections with Salmonella serotype Typhimurium DT104 in The Netherlands].

Salmonella remains an important source of food-related outbreaks of gastro-enteritis. In The Netherlands, regional laboratories send cultured Salmonella isolates to the National Institute of Public Health and the Environment (RIVM) for sero- and phage typing. Abnormal increases in the incidence of Salmonella infections are monitored by means of surveillance. Since the middle of September 2005, there has been a sharp increase in Salmonella Typhimurium DT104 (Dutch phage type 506 and 401) isolates, from all parts of the country and mainly from 6- to 20-year-olds. Since a first series of telephone interviews did not yield a clear source of the outbreak, a more extensive, written study has been started in a larger group of patients and corresponding controls.

Adolescent↗
PubMed2005

Long-term surveillance of invasive group A streptococcal disease in The Netherlands, 1994-2003.

A nationwide laboratory-based surveillance study of invasive group A streptococcal (GAS) infections was conducted in The Netherlands from May 1994 until December 2003 (average population during this period was 15 729 704). Microbiologically invasive isolates were obtained from 1504 patients, with most (70%) isolates cultured from blood. There was a clear seasonal pattern in invasive streptococcal infections, with an estimated annual incidence that peaked in 1996 (4.0 cases/100 000 individuals/year) and was at its lowest in 1999 (2.0 cases/100 000 individuals/year). Twenty-eight different M-types were identified, of which the most frequent were M1 (339/1504, 23%), M3 (187/1504, 12%), M89 (174/1504, 12%), M28 (164/1504, 11%), M12 (109/1504, 7%) and M6 (55/1504, 4%). There was a high degree of variation in the relative annual contributions of the predominant M-types, but variations in M1 and M3 combined correlated with overall changes in the annual incidence. The contribution of the patient group aged > or = 56 years to all cases of invasive GAS disease increased during the study period, whereas that of the group aged 0-20 years decreased. A peak in the incidence of invasive GAS disease among the patient group aged 30-34 years did not vary during the study period, indicating that the high incidence of invasive GAS disease in this age group was age-specific rather than cohort-related.

Adolescent↗
PubMed2005

Electronic reporting improves timeliness and completeness of infectious disease notification, The Netherlands, 2003.

In 2002, the internet based reporting system OSIRIS was introduced in the Netherlands and by the end of that year had fully replaced the paper-based reporting system. The objectives of OSIRIS were to improve timeliness and completeness of surveillance data on infectious diseases reported from regional to national level. We compared the timeliness of infectious diseases reported by the conventional paper-based system in 2001 with those reported by OSIRIS in 2003. Two distinct types of delay were compared: (1) total delay: defined as time between symptom onset and reporting at national level and (2) central delay: defined as time between regional and national reporting. Median delays between both systems were compared using the Wilcoxon Rank Sum-Test. We also compared electronic reports received via OSIRIS in 2003 to those received through the conventional system for 2001 for completeness of specific data fields. The Fisher exact test and the Mantel-Haenzel test with Yates correction were used to determine the significance of proportions of completed data fields in each system. Results showed the median central delay was significantly reduced for all diseases in OSIRIS compared to conventional reporting system. Overall, the median central delay was reduced from 10 days (interquartile range 4) in 2001 to 1 day (interquartile range 1) in 2003. Except for cases of malaria, the total delay, from symptom onset to national reporting, was also significantly reduced. In addition, OSIRIS records contained more complete information than conventional records. In total, in 2003, 92.3% of data field examined were complete compared with 81.3% in 2001. This study documents the benefits of electronic reporting of infectious disease surveillance data in terms of improved timeliness and completeness.

Clinical Laboratory Information Systems↗
PubMed2005

Completeness of malaria notification in the Netherlands 1995-2003 assessed by capture-recapture method.

In 1999 in the Netherlands, the duty to notify malaria was transferred from physicians to laboratories by the new Infectious Diseases Law. To evaluate the effect of this change, we aimed to estimate completeness of malaria notification in the Netherlands from 1995-2003. We calculated it relative to sentinel laboratory and hospital admission data. Using the two-source capture-recapture method (CRM), we estimated the total number of cases to assess the completeness relative to this number. The completeness of notification relative to sentinel data was 18.2 % (95% CI of 15.7-20.7) from 1995-1998 and 56.4 % (95% CI of 47.0-65.8) for 2000-2003. The completeness relative to the number of malaria cases admitted to the hospital was 35.1 % for the period 1995-2003. The estimated numbers of cases of malaria between 1995 and 1998 were 3123 (95% CI of 2796-3449) and 5043 (95% CI of 4343-5742) between 2000 and 2003. The completeness relative to this numbers changed from 35.5 % (95% CI of 32.1-39.7) in 1995-1998 to 36.1 % (95% CI of 31.7-41.9) for the years 2000-2003. Laboratory-based notification has significantly increased the absolute number of malaria notifications, but there was no change in completeness relative to hospital admissions. The increase in estimated malaria cases may be artificial, due to the extent of violation of CRM requirements over the study period.

Disease Notification↗
PubMed2004

[Surveillance of hepatitis A in the Netherlands 1993-2002].

OBJECTIVE: To survey trends in data on hepatitis A using information from the notification system of the Municipal Medical and Health Services 1993-2002. DESIGN: Retrospective, descriptive. METHOD: Data collected from the notification system of the Dutch Municipal and Medical Services were analyzed. RESULTS: From 1993 to 2002, 64.4%, 6.5% and 11.5% of infections were contracted in the Netherlands, Turkey and Morocco, respectively. Although the absolute number of cases was highest for young people under the age of 16 infected in the Netherlands, incidence rates showed that the children of immigrants infected in Turkey or Morocco were at highest risk, followed by adult immigrants from Turkey and Morocco. In addition, a seasonal trend was observed starting with an increase in the number of notifications of young travellers infected in Turkey and Morocco during their summer holiday, followed by a steep increase in notifications of young people infected in the Netherlands in autumn. This was followed later in the year by a slight increase in notifications of adults who acquired the infection in the Netherlands. However, between 1993-2002 the total number of notifications was halved. This decrease was mainly restricted to infections acquired in the Netherlands. In recent years, fewer outbreaks have been reported in schools, households and families. In 2001, a peak of notifications from the homosexual scene was observed. There was a continued trend in the rise of the mean age of hepatitis-A onset. CONCLUSION: Risk of hepatitis A is highest for the children of immigrants travelling to Turkey or Morocco in the summer months. Secondary cases in the Netherlands are in strong decline, especially in schools and families. However, the almost stable incidence of infections among young people of Turkish or Moroccan extraction stresses the continued importance of immunization of this group before they travel. The continuing trend in the rise of the mean age of hepatitis-A onset deserves attention because of the increasing risk of mortality of the disease amongst older people.

Adolescent↗
PubMed2003

Breast cancer and post-menopausal hormone therapy.

From the introduction of post-menopausal hormone replacement therapy (HRT) there has been great concern that HRT could possibly increase the risk of breast cancer. Prolonged exposure to endogenous oestrogens undeniably increases the risk of breast cancer. Questions that are important and until now only partly answered, are the following. Are oestrogens tumour promoters, as they induce mitosis, lead to proliferation and, therefore, accelerated growth of clinically occult pre-existing tumours? In addition to this, are they genotoxic mutagenic carcinogens, or could they initiate tumours by way of accumulation of incessant DNA-replication damage mechanism? Opinions vary as to the effect of the addition of a progestogen. There is a multitude of different progestogens which could bind with differing affinity to progesterone receptor PR-A or PR-B, and which have different physiological functions via differential gene regulation. The action of a progestogen on the oestrogen-induced cellular mitotic activity could be synergistic or antagonistic (by different pathways: oestrogen receptor downregulation, activating of metabolic pathways within the breast or stimulation of apoptosis)? Over 60 observational studies and two randomized trials provide evidence that the small but significant increase in risk appears with long-term current post-menopausal hormone use. The addition of a progestogen does not decrease the risk as seen with oestrogens alone and might increase the risk further. It is not clear whether there is a difference in risk with sequentially combined versus continuously combined HRT. Many questions nevertheless still remain. Is the risk increase limited to lean women only? What about risk-modifying factors such as alcohol use and a positive family history for breast cancer? Are tumours detected under HRT less aggressive, is there a better prognosis and is the mortality not increased while morbidity is? And is HRT contraindicated for women with a positive family history for breast cancer or in those women who have been treated for breast cancer? And finally, are there alternative options for these women?

Breast Neoplasms↗
PubMed2003

Investigation of an unexplained skin disorder in a prison clinic in the Netherlands in 2002.

An unexplained outbreak of skin disorder with itching papules or pustules occurred among drugs body packers in a detention clinic in the Netherlands in October-November 2002. The descriptive cohort study suggests this outbreak could be associated with an expired batch of disposable linens, with an overall attack rate of 30% in the study population (n=118). No additionnal cases have been noted since this expired batch was replaced.

Abdomen↗
PubMed2003

Surveillance of HCV infection in the Netherlands.

Two surveillance systems exist in the Netherlands to monitor hepatitis C (HCV) infections. Aggregated weekly laboratory data have been available since 1990. In 1999, HCV infection became a notifiable disease. Data showed the number of reported cases has remained stable. Male cases predominated (66%), mainly between age 15 to 54. Injecting drug use was the main route of transmission (64%). Despite its added value, the notifiable system should include more clinical data to better scrutinize future changes in transmission patterns.

Adolescent↗
PubMed2003

[Epidemiology of malaria in a village of Sudanese savannah in Mali (Bancoumana). Anti-TRAP and anti-CS humoral immunity response].

Vaccine development research is an important component of malaria control strategies. Thrombospondin related anonymous protein (TRAP) and the circumsporozoite (CS) protein are two antigens of sporozoite surface. Immune response to these two antigens may contribute to the development of anti-sporozoite vaccine. Recent studies suggest that antibodies anti-TRAP may partially block sporozoites penetration in hepatocyte, and thereby reducing malaria morbidity. We carried out a study to assess the seroprevalence of anti-TRAP and anti-CS antibodies and to identify a possible role of these antibodies on malaria morbidity in children 1-9 years old living in a rural hyperendemic village. We performed 5 cross sectional surveys and a longitudinal follow up in 1993 and 1994. During each cross sectional study, children were examined for fever and splenomegaly; all febrile children received thick film examination, and serologic analysis was performed in one third of these, randomly selected. The results show that the seroprevalence of anti-TRAP and anti-CS varied with age and season (p < 0.05). Association between the prevalence of anti-TRAP and splenomegaly was observed during two cross sectional surveys (June and October 1993). The presence of anti-TRAP antibody was associated with Plasmodium falciparum infection at the beginning of the transmission season (June 1993 and July 1994). A negative association between the level of anti-TRAP title and parasitemia was observed (March and October 1994). These findings suggest no clear evidence of the protective role of anti-TRAP antibodies in uncomplicated malaria, possibly due to the limited persistence of these antibodies under natural situations.

Antibodies, Protozoan↗
PubMed2003

[Epidemiology of malaria in a village of Sudanese savannah area in Mali (Bancoumana). 2. Entomo-parasitological and clinical study ].

We carried out five cross sectional surveys between 1993 and 1994 to assess the epidemiology of malaria in the village of Bancoumana, located in the Sudanese savannah areas of Mali. Each survey included a collection of entomological, clinical, parasitological and immunological data. The study population involved 1600 children from six months to 9 years of age. The main vector was Anopheles gambiae s.l., man bite rate and entomological inoculation rate were maximum respectively in August (peak of the transmission season) and October (end of transmission season). Plasmodium. falciparum was the main parasite species observed. Spleen enlargement rate, parasite rate, gametocyte rate and parasite density varied significantly with age and season. The parasite rate, gametocyte rate and parasite density were significantly low in October 1994 compared with October 1993 while the entomologic parameter did not show any variation over the two years. This reduction of parasitologic index between 1993 and 1994 may be related to an increase of anti-malarial drug use in the population. Our results show that malaria is hyperendemic in the village of Bancoumana.

Animals↗
PubMed2000

Evaluation of two PCR-based procedures for typing Clostridium perfringens.

Two polymerase chain reaction (PCR)-based procedures for typing Clostridium, perfringens, which affects most domestic animals, were compared and evaluated for efficiency as substitute to the guinea-pig intradermal test routinely used in our laboratory, namely a multiplex PCR and a protocol based on the individual amplification of gene sequences specific for each toxin. Reference isolates of C. perfringens types A, B, C and D as well as cultures from clinical specimens were tested. The sensitivity and specificity of the PCR was confirmed on reference isolates. There was similarity in results on 43 of the 46 samples typed by all 3 methods. Clear results were obtained by PCR on 5 clinical samples that showed either equivocal or weak skin reactions in guinea-pigs. The multiplex PCR protocol, in combination with the evaluation of bacterial growth, is a better alternative to in vivo toxin typing, since C. perfringens can only be incriminated as cause of a disease when it is present in large numbers in the intestine.

Animals↗
PubMed2000

The community-based malaria control programme in Tigray, northern Ethiopia. A review of programme set-up, activities, outcomes and impact.

Tigray, the northernmost state of Ethiopia, has a population of 3.5 million, 86% rural, and 56% living in malarious areas. In 1992 a Community-Based Malaria Control Programme was established to provide region-wide and sustained access to early diagnosis and treatment of malaria at the village level. 735 volunteer community health workers (CHWs) serve 2,327 villages with a population of 1.74 million, treating an average of 489,378 patients yearly from 1994 to 1997. Recognition of clinical malaria is similar for CHWs and health staff at clinics where there is no access to microscopy. In 1996 a pilot community-financing scheme of insecticide-treated bednets was well accepted, but re-impregnation rates fell in 1998 because of war-related social upheaval. Indicators from health institutions show a progressive increase in malaria morbidity from 1994 to 1998. Repeated mortality surveys show a 40% reduction in death rates in under-5 children from 1994 to 1996 and a 10% increase from 1996 to 1998. These trends may be related to increased malaria transmission with water resources development, increased seasonal labour migration to malarious lowlands, prolongation of the transmission season with climate changes, and increasing chloroquine resistance throughout Ethiopia. Progressive extension of CHW services to ensure better coverage of women, children, migrant workers and communities near water development projects, change to first-line treatment with sulfadoxine-pyrimethamine, extension of the impregnated bednet initiative, and development of a regional warning system for epidemics should result in a greater impact on morbidity and mortality.

Age Factors↗
PubMed1999

[Syphilis in addicted pregnant women: better care through more awareness and contract between organizations involved].

Three women, aged 21, 20 and 30 years, were cocaine users and pregnant. There had been no prenatal monitoring until they reported with uterine contractions. Blood of the first two women was then tested; serology revealed active syphilis infections: their children had died in utero. The blood of the third woman had been tested as part of a street project; it revealed an active syphilitic infection but she could not be found for treatment. After delivery, the child showed withdrawal symptoms. The first and third women and the child of the third woman were treated with benzylpenicillin. The system for screening and treating drug-addicted pregnant women should be intensified.

Adult↗
PubMed1999

[Increase of early syphilis in Rotterdam (1995-1997): more (addicted) prostitutes and their clients].

OBJECTIVE: To detect risk groups in an increase of early (infectious) syphilis. DESIGN: Retrospective study of patient records. METHOD: Data from visitors with an early syphilis were collected from their respective medical records in the outpatient clinic for sexually transmitted diseases (STD) of the Academic Hospital Rotterdam-Dijkzigt, the Netherlands, over the years 1993-1997. In particular, data on risk behaviour and risk groups were collected. To obtain an indication of the (possible) causes of the increase in the number of visitors with early syphilis, (shifts in) characteristics of this population over the years were compared. RESULTS: 195 patients with early syphilis had visited the outpatient clinic, 130 males and 65 females, mean ages ranging from 30.9 (1993) to 38.1 years (1997). Most infected persons (68%) came to the outpatient clinic because of symptoms. The number of women who came to the outpatient clinic through partner notification increased considerably, from an average of 5% in 1993-1995 to 36% in 1996. Over the years a relative increase of (drug addicted) prostitutes and their clients was observed (1993-1995: 39%; 1996: 56%). CONCLUSION: The cause of the increase, or failure to decrease, of the number of syphilis-infected visitors in the STD outpatient clinic of the Academic Hospital Rotterdam-Dijkzigt should probably be sought among (drug addicted) prostitutes and their visitors.

Adult↗
PubMed1999

[Increase of early syphilis in a red light district in Rotterdam (1995-1997) and preventive treatment].

The number of cases of syphilis in Rotterdam has increased dramatically since 1995. The prevalence of early syphilis in 1997 was highest among street prostitutes (16%). Some prostitutes could not be reached for further evaluation and treatment, probably due to their addiction to hard drugs. Prophylactic treatment for syphilis was given to most street prostitutes in a cruising zone during a screening programme for sexually transmitted diseases (STD) in January 1997. Since then, STD checkups were performed regularly in the cruising zone. The prevalence of early syphilis in the cruising zone dropped to 1.3% in 1998. The total number of reported cases of syphilis in Rotterdam also decreased sharply in 1998.

Adult↗
PubMed1999

[Two patients with acute hepatitis B from the same piercing salon].

Hepatitis B was diagnosed in two homosexual men aged 41 and 31 years. Both had undergone piercing on the same day in the same saloon. The word piercing means application of decorations in the skin which is pierced for the purpose. The breeching of the skin combined with the conditions under which this is performed leads to a risk of transmission of especially viral infections. An assumed connection between the patients was supported by the results of molecular-biological examination of the hepatitis B virus isolates. The piercings were applied with the same pair of pincers, which was not sterilized in between. In view of these findings hygienic measures were taken in the piercing saloon in question to prevent future transmission of infections. Piercing entails health risks that are not always recognized either by those who do it or by those who have it done.

Acute Disease↗
PubMed1999

[Screening policy for travellers from Rotterdam for hepatitis A antibodies prior to eventual immunization: favourable cost-benefit ratio].

OBJECTIVE: To evaluate costs and benefits of the screening and immunisation policy for hepatitis A virus (HAV) infection among travellers from Rotterdam. DESIGN: Descriptive and cost-benefit analysis. METHOD: From the data of the Municipal Health Service Rotterdam (GGD), the Netherlands, the details were collected on individuals travelling frequently to HAV endemic countries, who were born before 1950, or had lived for more than 10 years in an HAV endemic country or had ever suffered jaundice. Persons to whom these criteria applied were screened for HAV antibodies at the GGD before immunisation for HAV in the period January 1st 1996-June 30th 1998. Screening and vaccination policies were compared with a cost analysis. RESULTS: Antibodies against HAV were found in 79% of 1466 screened people. The lowest prevalence of antibodies was found among Dutch nationals (67%). A significantly higher prevalence was found amongst individuals from Turkey/Morocco (96%) and from the Cape-Verde Islands (97%). In the cost analysis the break even point, the prevalence level of HAV antibodies in the population at which screening cost as much as blind prophylaxis, lay for passive immunisation between 69% and 93%. For active immunisation this point lay around 17%. CONCLUSION: The selection criteria for prevaccination screening are effective in identifying individuals with a high probability of being immune against HAV infections. The current screening policy for antibodies against HAV is cost effective.

Cost-Benefit Analysis↗