[A midwife involved in patients with puerperal fever in three different hospitals]. / Een verloskundige betrokken bij patiënten met kraamvrouwenkoorts in drie verschillende ziekenhuizen.

In three hospitals three women aged 34, 33 and 25 years respectively, developed fever following delivery; in two of them a beta-haemolytic streptococcus of Lancefield group A (GAS) was cultured. Between the time of transmission of the infective agent of the first and the third patients there was a period of ten days. Because the intervals between the emergence of cases were relatively long, the suspicion of a common vector, i.e. the midwife, was raised only after some time. The midwife who had been present at all three deliveries turned out to be negative for GAS carriership on three occasions. However, cultures taken from her son and partner were positive for GAS carriership. A number of typing systems were unable to distinguish the GAS-isolates from the first two patients and from the son. After the midwife and her family members had been treated, no new cases occurred. This case illustrates the importance of keeping midwives as well as the department of public health informed of a rise in the number of cases of puerperal fever, whether the cases involve more than one hospital or not, in order to prevent a potential epidemic. Only then can a common source be looked for and the epidemic contained.

[Typhoid fever in Amsterdam, 1991-2000, and the simplification of the national protocol for source and contact tracing]. / Buiktyfus in Amsterdam, 1991-2000, en vereenvoudiging van het landelijk protocol voor bron- en contactopsporing.

OBJECTIVE: To determine the incidence of patients reported with typhoid fever in Amsterdam (1991-2000) and to evaluate the contact tracing for those patients with the specific objective of examining whether contact tracing can be simplified. DESIGN: Retrospective. METHOD: From an automated database, data were collected on all reported typhoid fever patients in Amsterdam during the period 1991-2000 and on their contact persons. RESULTS: One hundred and one patients with typhoid fever were reported during the study period, and Salmonella typhi infection was diagnosed in 12 of the 281 household contacts. For 96 of the 101 index patients, travelling abroad was the most likely source of infection. In 8 of the 12 contact persons with an S. typhi infection, the index person was the most likely source of infection, which is equivalent to a secondary transmission rate of 2.8% (8/277). Seven of the 8 secondary infected persons had symptoms indicative of typhoid fever infection and S. typhi was found in all their first stool samples. CONCLUSION: Supported by these results, the national guidelines for source and contact tracing in the case of typhoid fever have been amended. In the case of index patients with bad toilet hygiene or who are responsible for food preparation, the faeces of all household contacts must be examined once. If the contact persons have symptoms indicative of an S. typhi infection and/or if their work involves food preparation, their faeces should also be tested once. The changes to the national protocol will markedly reduce the labour-intensity of tracing and testing the contacts of patients with typhoid fever, thereby maintaining the quality of the process. Tracing the source of infection in the case of patients with typhoid fever will also remain important in the future in order to detect potential transmission within the Netherlands at an early stage.

[An outbreak of vomiting and diarrhea in a nursing home caused by the Norwalk-like virus: implications of the Dutch law on infectious diseases and new diagnostic options]. / Een uitbraak van braken en diarree in een verpleeghuis, veroorzaakt door het Norwalk-achtig virus, in het licht van de infectieziektenwet en nieuwe diagnostische mogelijkheden.

Several residents on a psychogeriatric ward developed vomiting and diarrhoea within a short time of each other. The causal factor was the highly contagious Norwalk-like virus (NLV) with a high rate of infection amongst both residents and staff (84%). This virus is the most frequent cause of gastroenteritis in institutions. The illness is self-limiting and can be transmitted from person to person. In weakened individuals the course can be serious. The virus can be detected in faeces with modern molecular-biological techniques (reverse transcriptase PCR). The revised law on infectious diseases ('Infectieziektenwet') was established in the Netherlands in 1999. This law requires major outbreaks of infectious diseases in institutions as described here to be reported to the Municipal Health Service. Together with this agency, strategies to prevent further spread of the disease can be implemented.

Association of tuberculin sensitivity in Dutch adults with history of travel to areas of with a high incidence of tuberculosis.

International travel may be a source of introduction of tuberculosis into low-incidence countries. We assessed whether, in The Netherlands, sensitivity to tuberculin was associated with a history of travel to countries with a high incidence of tuberculosis. Immunocompetent adults with no history of Bacille Calmette-Guérin vaccination or sensitivity to tuberculin were skin-tested simultaneously with 1-tuberculin unit (TU) purified protein derivative (PPD) of Mycobacterium tuberculosis and 1-TU sensitin of Mycobacterium scrofulaceum. Tuberculin sensitivity was defined as a reaction to PPD of > or =10 mm that was > or =3 mm larger than the reaction to M. scrofulaceum sensitin. Tuberculin sensitivity was found in 7 (0.7%) of 1014 participants (95% confidence interval [CI], 0.3%-1.4%); it was independently associated with a cumulative history of >3-months' travel to high-incidence areas (odds ratio, 6.0; 95% CI, 1.2-31.2; P=.016) and increased in association with total duration of travel (P=.02). Travel to high-incidence areas increases the risk of tuberculin sensitivity and, consequently, of latent tuberculous infection. In countries with a low incidence of tuberculosis, cases of infection acquired during travel may account for a substantial proportion of new infections in the resident population.

Risk of infection with Mycobacterium tuberculosis in travellers to areas of high tuberculosis endemicity.

BACKGROUND: No data exist on risks of infection with Mycobacterium tuberculosis in travellers. We studied incidences of and risk factors for tuberculin skin-test conversion among Dutch long-term travellers to countries of high tuberculosis endemicity. METHODS: In a multicentre, prospective cohort study based in travel and tuberculosis clinics in the Netherlands, 1072 BCG-naive immunocompetent travellers to countries with an estimated annual risk of M. tuberculosis infection of at least 1% were skin tested before departure with 1 tuberculin unit purified protein derivative (PPD) of M. tuberculosis in Tween-80. Those with results less than 2 mm were retested 2-4 months after their return with simultaneous testing for cross-sensitivity to environmental mycobacteria (1 tuberculin unit PPD of M. scrofulaceum in Tween-80). M. tuberculosis infection was defined as a post-travel M. tuberculosis tuberculin skin-test result of at least 10 mm that was 3 mm or more larger than the M. scrofulaceum result. FINDINGS: Post-travel skin-test results were available for 656 (66%) of 988 individuals who were eligible for follow-up. Among these, 12 M. tuberculosis infections were identified (1.8%). The overall incidence rate was 3.5 per 1000 person-months of travel (95% CI 2.0-6.2), and 2.8 per 1000 person-months of travel (1.2-5.5) after exclusion of health-care workers. Two had active tuberculosis at the time of testing (incidence rate 0.6 per 1000 person-months of travel [0.3-2.3]). Work in patient care abroad was an independent risk factor (adjusted rate ratio 5.34, p=0.015). INTERPRETATION: The risk of M. tuberculosis infection in long-term travellers to high-endemicity countries, even if not engaged in health-care work, is substantial and of similar magnitude to the average risk for the local population. BCG vaccination or post-travel tuberculin skin-testing of high-risk travellers should be considered.

[Malaria: under-notification and risk assessment for travelers to the tropics]. / Malaria: onderrapportage en risicoschatting voor tropenreizigers.

OBJECTIVE: To define the risk of contracting malaria for travellers to malaria-endemic areas and to calculate the under-notification under the current notification system. DESIGN: Retrospective epidemiological analysis. SETTING: Agricultural University Wageningen, The Netherlands. METHODS: Risks of contracting malaria were estimated by calculating the incidence per 100,000 travellers. This incidence was found using an estimated under-notification calculated on the basis of data from the "SIG Zorginformatie' (hospital cases) and the Medical Health Inspectorate (notified cases). RESULTS: The average under-notification in the Netherlands was at least 59% in the period January 1988 to June 1993 inclusive and increased by 10% each year. Judging by this estimation at least 3170 travellers returned to the Netherlands with malaria in this period. The risk in Africa appeared to be decreasing. In Asia the malaria incidence increased slightly in recent years while no trend was found for America. The imported malaria was mainly caused by Plasmodium falciparum. CONCLUSION: In order to improve the malaria notification system in the Netherlands a notification obligation for all microbiological laboratories should be introduced as almost all malaria is diagnosed there.

[A case of food poisoning caused by C. perfringens]. / Een geval van voedselvergiftiging door C. perfringens.

A case of food borne infection among a hundred inhabitants of a home for the old aged, caused by Clostridium perfringens (Clostridium welchii) following consumption of a filled veal roll is reported.