Methicillin-resistant Staphylococcus aureus in people living and working in pig farms.

We compared the prevalence of human and animal methicillin-resistant Staphylococcus aureus (MRSA) at pig farms in The Netherlands, and related this to individual and farm-level characteristics. More than half of the farms investigated (28/50) had MRSA in pigs or stable dust and about one third (15/50) of person(s) were identified as MRSA carriers. Human carriage was found only on farms with MRSA-positive pigs or dust. MRSA strains in human samples were the same spa-type as found in pigs and all were not typable by pulsed-field gel electrophoresis (NT-MRSA). Multivariate analyses showed that risk factors for human MRSA carriage were: working in pig stables (OR 40, 95% CI 8-209) and the presence of sows and finishing pigs (OR 9, 95% CI 3-30). Veterinary sample collectors sampling the pigs showed transient MRSA carriage only during the day of the farm visit. Working in pig stables with MRSA-positive pigs poses a high risk for acquiring MRSA, increasingly so when contact with live pigs is more intensive or long lasting.

High prevalence of methicillin resistant Staphylococcus aureus in pigs.

Recently methicillin resistant Staphylococcus aureus (MRSA) was isolated from pigs and pig farmers in The Netherlands. In order to assess the dissemination of MRSA in the Dutch pig population, we screened 540 pigs in 9 slaughterhouses, where a representative portion of Dutch pigs (63%) was slaughtered in 2005. We found 209 (39%) of the pigs to carry MRSA in their nares. Forty-four of 54 groups of 10 consecutive pigs (81%), each group from a different farm, and all slaughterhouses were affected. All MRSA isolates belonged to 1 clonal group, showing Multi-Locus Sequence Type 398 and closely related spa types (mainly t011, t108 and t1254). Three types of the Staphylococcal Chromosome Cassette (SCCmec) were found: III (3%), IVa (39%) and V (57%). All 44 tested isolates (1 isolate per group) were resistant to tetracycline, reflecting the high and predominant use of tetracyclines in pig husbandry. Twenty-three percent of the isolates were resistant to both erythromycin and clindamycin and 36% to kanamycin, gentamicin and tobramycin but only a single isolate was resistant to co-trimoxazole and none to ciprofloxacin and several other antibiotics. The percentage of MRSA positive pigs was significantly different among slaughterhouses and among groups within slaughterhouses, indicating a high prevalence of MRSA in pigs delivered from the farms as well as cross contamination in the slaughterhouses.

A one-year intensified study of outbreaks of gastroenteritis in The Netherlands.

In 2002, in The Netherlands a national study of gastroenteritis outbreaks was performed. Epidemiological information was collected by the Public Health Services (PHS) and the Food Inspection Services (FIS) using standardized questionnaires. Stool samples were collected for diagnostic testing. For foodborne outbreaks, food samples were taken. In total, 281 gastroenteritis outbreaks were included, mainly from nursing homes and homes for the elderly (57%), restaurants (11%), hospitals (9%) and day-care centres (7%). Direct person-to-person spread was the predominant transmission route in all settings (overall 78%), except for restaurant outbreaks where food was suspected in almost 90% (overall in 21% of outbreaks). The most common pathogen was norovirus (54%), followed by Salmonella spp. (4%), rotavirus group A (2%), Campylobacter spp. (1%) and only incidentally others. In conclusion, most outbreaks were reported from health and residential institutions, with norovirus as the dominant agent. Control should aim at reducing person-to-person spread. In foodborne outbreaks norovirus was common, due to contamination of food by food handlers. Salmonella, as the second foodborne pathogen, was mainly associated with raw shell eggs. These results stress the continuous need for food safety education, complementary to governmental regulation.

Transcutaneous oxygen tension in patients with and without pericapillary fibrin cuffs in chronic venous insufficiency, porphyria cutanea tarda and non-venous leg ulcers.

To evaluate the influence of fibrin cuffs on the transcutaneous oxygen tension in patients with chronic venous insufficiency (CVI) we performed a prospective comparative study in an out-patient dermatological department of a district hospital in the Netherlands. 16 patients with CVI grade II or III, 6 patients with porphyria cutanea tarda (PCT) without any sign of CVI, 4 patients with clinical ecthyma type ulcers without CVI and 10 healthy volunteers were studied. Skin biopsies for fibrinogen staining, transcutaneous oxygen tension measurements (TcPO2) and light reflexion rheography (LRR) were performed. TcPO2 readings were significantly lower in patients with CVI compared to patients of the other groups. Fibrin cuffs were found in 8 out of 16 patients with CVI, all PCT patients and 3 out of 4 ecthyma-ulcer patients. On the basis of these results we conclude that the fibrin cuff alone does not act as a barrier for oxygen transport. Fibrin cuffs in CVI are not the cause of venous ulceration but only a part of the complicated mechanism of the altered microcirculation induced by reflux in the venous macrocirculation. Fibrin cuffs are not unique for CVI but an indication of a disturbed microcirculation.

A comparative clinical trial of graduated compression stockings and O-(beta-hydroxyethyl)-rutosides (HR) in the treatment of patients with chronic venous insufficiency.

As overall conclusions from this study, and the two preceding comparable trials in which TcPO2 was measured in patients with (8) and without (7) stockings, we propose that: All patients with symptoms and oedema of CVI should be advised to wear suitable compressive stockings (this study); if they do wear stockings, then additional benefit may be derived from treatment with HR (8); for patients who are reluctant to wear stockings, for a variety of reasons, or in whom stockings may be contraindicated (e.g. mixed arterio-venous disease), then HR is an acceptable alternative (7 and this study).

Cyclosporin in atopic dermatitis: a multicentre placebo-controlled study.

The efficacy of cyclosporin (Sandimmun) given in a daily dose of 5 mg/kg for 6 weeks in severe atopic dermatitis was confirmed in this double-blind, placebo-controlled, short-term study. Of the 46 patients included in the study, 23 were randomized to receive cyclosporin and 23 to receive placebo. Four of the 23 patients (17%) on cyclosporin, and 14 of the 23 patients (61%) who received placebo, discontinued the trial because of inefficacy. All patients who discontinued the trial were assessed following the principle of 'intention to treat'. Compared with the baseline, the mean scores for disease severity [6-area, total body severity assessment (TBSA)] improved by 55%, and the mean scores for extent of disease [rule-of-nines area assessment (RoNAA)] improved by 40%, in patients treated with cyclosporin. Nine of the patients who received cyclosporin and completed the study (n = 14) had an individual reduction of disease severity (TBSA) of 75% or more, and in three patients this reduction was nearly 100%. In the placebo group, a mean worsening of disease severity (4%) and of extent of the disease (25%), compared with the baseline, was observed at week 6. Patients' and investigators' mean scores for the overall efficacy were similar, and showed a statistically significant difference in favour of cyclosporin. Two patients on cyclosporin developed hypertension during therapy, and one of these withdrew from the study. At the end of the trial, no statistically significant differences in the systolic or diastolic blood pressures were observed between the two groups. In the cyclosporin group, the increases in the values of serum creatinine and bilirubin at week 6, compared with the respective values at the baseline, were statistically significantly different from those in the placebo group, but all values normalized in the post-treatment period. Cyclosporin can be a safe and very effective treatment in episodes of severe atopic dermatitis, provided that the recommended guidelines for its administration are strictly observed.

Increased collagen IV layer in the basal membrane area of the capillaries in severe chronic venous insufficiency.

Lipodermatosclerosis is a sign of severe chronic venous insufficiency. In this stage of CVI one can find capillary leakage of water and plasmaproteins which results in a higher capillary filtration rate. In skin biopsies the result of this process can be seen as a pericapillary halo. The group of Burnand recently described fibrinogen deposits in this area. We studied the capillaries and their surrounding tissue to determine the thickness of the collagen IV deposits. In severe CVI with lipodermatosclerosis a significant increase of the collagen IV layer was observed. Collagen IV thickness was measured by an index method. The collagen IV thickness for this purpose refers to the capillary diameter. It can be suggested that the increase of the venous pressure in the capillaries leads to leakage of several proteins and namely fibrinogen. As a result of the increase of fibrinogen the collagen IV layer becomes thicker which leads to a decreasing function of the capillaries. In this way an auto-amplification mechanism maintains CVI. An other explanation can be induction of collagen IV due to the high capillary pressure in CVI.

[Endocarditis and meat inspection in slaughtering pigs. 1. Clinical, pathological and microbiological aspects]. / Endocarditis en vleeskeuring bij slachtvarkens. 1. Klinische, pathologische en microbiologische aspecten.

The clinical, pathomorphological and microbiological findings during meat inspection in 599 pigs with endocarditis at slaughter were studied. Clinical signs were observed in 41 per cent of the pigs on ante-mortem inspection. Lameness was the most common sign. However, this symptom is not very specific of endocarditis. This is also true of various other symptoms. Only dyspnoea and drowsiness were indicative of endocarditis to some extent, but occurred only sporadically. Extracardial lesions were observed in 66 per cent of the pigs with endocarditis on post-mortem inspection. Metastatic processes (infarction or inflammatory foci) were most frequently detected in the kidneys. These were highly specific of endocarditis. In addition, the following changes were observed in decreasing incidence: signs of sepsis (hyperplastic splenitis, petechiae and degradation of organs), inflammatory lesions of the joints and legs, metastatic pneumonia and inflammation of the tail. Bacteriological examination was positive in 62 per cent of the cases. Streptococci were the organisms most frequently isolated (36 per cent), followed by Corynebacterium pyogenes (19 per cent) and Erysipelothrix rhusiopathiae (14 per cent). The discussion is concerned with the significance of these bacteria to meat-consumers.

[Endocarditis and meat inspection in slaughtering pigs. 2. Various aspects of meat inspection]. / Endocarditis en vleeskeuring bij slachtvarkens. 2. Keuringsaspecten.

The results of meat inspection in 599 slaughtered pigs with endocarditis were studied. Of the pigs examined, 65 per cent were condemned. Condemnation was based on a positive bacteriological examination (Article 2 of the Meat Inspection Regulations) in almost every case. When bacteriological examination was negative, the animal was passed unqualified in nearly every case, regardless of the fact that symptoms were or were not detected in ante-mortem inspection and whether or not signs of sepsis were observed. Subsequently, efforts were made to determine the possible effects of omitting incisions into the hearts of pigs in which neither clinical nor morbid-anatomical examination suggested the presence of endocarditis. It was concluded that endocarditis would have passed unnoticed in 25 per cent of the pigs examined in this case. Of these pigs, fifty per cent were found to be positive on bacteriological examination. Finally, the financial consequences of condemning all pigs showing endocarditis were examined. Compared with current practice in meat inspection, this would result in an annual loss of Dfl. 60,000 in the situation prevailing in the Netherlands. However, if Articles 13, 17 and 18 of the Meat Inspection Regulations were strictly observed, the yield of the pigs passed would not offset the costs of examination.

Occurrence of Vibrio parahaemolyticus in Dutch mussels.

A study was carried out on the occurrence of Vibrio parahaemolyticus in Dutch mussels originating from the East Schelde Estuary. In a totol of 79 10-g tissue samples, 3 (3.8%) were found to contain V. parahaemolyticus. In a second survey, 6 out of 23 bags of mussels (26%) contained one or more strains of V. parahaemolyticus in 5-g tissue samples. The many limitations of current methodology used in such surveys are stressed. Positive samples can be missed because viable cells may die during refrigerated transport. Surviving cells also may not be detected because they have been sublethally stressed. In addition, the unreliability of the identification criterion of no growth in 10% NaCl was demonstrated.

Sublethal cold shock in Vibrio parahaemolyticus.

Exposing Vibrio parahaemolyticus populations to temperatures of 2 degrees C results in membrane damage, rendering cells incompetent to grow on media containing 5% NaCl.

[Food poisoning following consumption of canned meat prepared by a butcher (author's transl)]. / Voedselvergiftiging na consumptie van door een slager bereid vlees in blik

A case of food poisoning possibly caused by the ingestion of canned meat is reported. Large numbers of micro-organisms (approximately 10(7)/gram), mainly Enterobacteriaceae and streptococci, were isolated from the contents of three cans. The contents of another can contained approximately 10(5) Bacillus spp. per gram. The meat preserves had been prepared in a butcher's shop and heated in a "cooking pot", the steam holes of which had been stopped up and the lid of which had been made heavier in order to reach a temperature above 100 degrees C. Inadequate sterilization and errors in processing are suggested as possible causes.

[Meat-containing animal foods. (1) Histological study of tinned foods. (2) Legal regulations (author's transl)]. / Vleeshoudende diervoeders. 1. Histologisch onderzoek van conserven. 2. Wettelijke voorschriften

A number of random tinned foods marketed as dog or cat food in the Netherlands were studied histologically. The histological compositions of each food studied was described in terms of primary and secondary constituents. In almost every case, vegetable material was found to be the primary constituent. In addition, legal regulations regarding animal foods in the Netherlands are reviewed.