BACKGROUND: Food-borne salmonella infections have become a major problem in industrialized countries. The strain of Salmonella enterica serotype typhimurium known as definitive phage type 104 (DT104) is usually resistant to five drugs: ampicillin, chloramphenicol, streptomycin, sulfonamides, and tetracycline. An increasing proportion of DT104 isolates also have reduced susceptibility to fluoroquinolones. METHODS: The Danish salmonella surveillance program determines the phage types of all typhimurium strains from the food chain, and in the case of suspected outbreaks, five-drug-resistant strains are characterized by molecular methods. All patients infected with five-drug-resistant typhimurium are interviewed to obtain clinical and epidemiologic data. In 1998, an outbreak of salmonella occurred, in which the strain of typhimurium DT104 was new to Denmark. We investigated this outbreak and report here our findings. RESULTS: Until 1997, DT104 infections made up less than 1 percent of all human salmonella infections. The strain isolated from patients in the first community outbreak of DT104 in Denmark, in 1998 was resistant to nalidixic acid and had reduced susceptibility to fluoroquinolones. The outbreak included 25 culture-confirmed cases. Eleven patients were hospitalized, and two died. The molecular epidemiology and data from patients indicated that the primary source was a Danish swine herd. Furthermore, the investigation suggested reduced clinical effectiveness of treatment with fluoroquinolones. CONCLUSIONS: Our investigation of an outbreak of DT104 documented the spread of quinolone-resistant bacteria from food animals to humans; this spread was associated with infections that were difficult to treat. Because of the increase in quinolone resistance in salmonella, the use of fluoroquinolones in food animals should be restricted.
Comment In: N Engl J Med. 2000 Mar 2;342(9):66110702060
A total of 435 United States Geological Survey and United States Forest Service workers in Alaska were studied for serologic evidence of past infections with four arboviruses known or suspected to be human pathogens. Of the personnel tested, 36 (8.3%) had the neutralizing antibody to Jamestown Canyon but not snowshoe hare virus, 6 (1.4%) had the antibody to snowshoe hare but not Jamestown Canyon virus, 53 (12.2%) had the antibody to both viruses, 17 (3.9%) had the antibody to Northway virus, and 15 (3.4%) had the antibody to Klamath virus. The indices most significantly correlated with presence of the Jamestown Canyon and snowshoe hare antibodies were the amount of fieldwork (p less than 0.001 for both antibodies) and the duration of employment by the agencies (p less than 0.0001 for Jamestown Canyon and 0.004 for snowshoe hare). The antibody to the four arboviruses also correlated strongly with a history of travel in certain remote or wilderness areas in Alaska (p values ranged from less than 0.001 to 0.086).
To clarify whether a nosocomial outbreak of legionnaires' disease in the Värnamo hospital in Sweden was part of a wider outbreak in the Värnamo community a number of investigations were performed. First, the proportion of cases of legionnaires' disease in a group with nosocomially acquired pneumonia (11%) was compared to the proportion within a group with community-acquired pneumonia (14%) and the difference was found not to be significant (p > 0.05). Second, the proportion of the nursing staff at the Värnamo hospital with an elevated antibody titre (> or = 16) to Legionella pneumophila serogroup (sg) 1 (33%, 84/258) was compared to the proportion in a group of local residents of Värnamo community (26%, 25/96) and found not to be significant; in contrast, comparison with the proportion in a group from the assistant nursing staff at another hospital 60 km away (5%, 4/80) was highly significant (p
Due to their multiple antibiotic resistance properties, methicillin-resistant Staphylococcus aureus (MRSA) are a major public health problem. After the recently described emergence of MRSA in animals, the authors investigated the risk of nasal MRSA carriage among people with professional contact with animals.
Nasal swabs and information on animal exposure and known MRSA risk factors were obtained from participants (N=702) at five conferences organized by national veterinary and farmer associations and students at a business school in Denmark. All of the participants were screened by standard microbiological techniques for MRSA detection and characterization.
From 15 to 21 August 1981, Pontiac fever affected 317 automobile assembly plant workers. Results of serologic tests were negative for Mycoplasma, Chlamydia, respiratory tract viruses, and previously described legionellae. A gram-negative, rod-shaped organism (WO-44C) that did not grow on blood agar, required L-cysteine for growth, and contained large amounts of branched-chain fatty acids was isolated from a water-based coolant. The organism did not react with antisera against other legionellae, and on DNA hybridization the organism was less than 10% related to other Legionella species. Geometric mean titers found by indirect fluorescent antibody testing to WO-44C were significantly higher in ill employees than in controls (p = 0.0001). Attack rates by department decreased linearly with the department's distance from the implicated coolant system. The etiologic agent apparently was a new Legionella species; we propose the name Legionella feeleii species nova (AATC 35072). This is the first outbreak of nonpneumonic legionellosis in which the etiologic agent is not L. pneumophila, serogroup 1.
Since 2006 in Denmark, there has been a statutory order on physicians' notification of methicillin-resistant Staphylococcus aureus (MRSA). Occupational cases notified in North Denmark Region in 2008 and 2009 were analysed. Overall, 109 cases (54 females and 55 males) were notified, of whom 56 were infected and 52 cases were carriers, whereas in one case the status was unknown. The most prevalent clonal complex (CC) was 398 (n=26; 23.9%), followed by CC5 (n=17; 15.6%), CC30 (n=14; 12.8%), and CC8 (n=12; 11%). Eighteen cases were occupational with a predominance of CC398 (n= 16; 88.8%); CC8 and CC22 accounted for one case each. There was a significantly higher proportion of occupational cases for CC398 compared with other clonal complexes (p
Professional prevalence of tuberculosis of workers of health care is the important medico-social problem.
The study is based on the observation of the epidemic process of tuberculosis in the Omsk region for 2000-2014. Material for the study was the data of the forms of Federal statistical observation. There were used observational descriptive and evaluative research methods of the study.
In the Omsk region on the background of the downtrend of tuberculosis incidence there were observed qualitative changes in the nature of bacterioexcretion, characterized by the widespread occurrence of multidrug-resistant Mycobacterium. Over the study period 154 cases of occupational diseases in workers of medical institutions were registered Tuberculosis accounted for 80.5% of cases; at that 77.4% are employees of phthisiatric institutions, out of them nursing staff--48.3%, medical attendants--20.2%, doctors--18.5%, employees of the bacteriological laboratory--6.4%, workers of other support units--6.4%. Among diseased patients 41.1% were persons with the experience of working in harmful conditions from 1 to 5 years, 20%--experience of 5-10 years, 8.8%--working experience of 10 to 15 years, 29%--more than 15 years. In patients there was prevailed tuberculosis of respiratory organs--85.4% of cases, extrapulmonary forms of tuberculosis (tuberculosis of the genitourinary system, peripheral lymph nodes, eyes, central nervous system) accounted for 14.6%. About 30% of cases of tuberculosis among health care workers were accompanied by bacterioexcretion.
In conditions of the wide spread of drug-resistant Mycobacterium tuberculosis it is necessary to optimize the approaches to the prevention of tuberculosis among health care workers.
Tuberculosis (TB) is a well-known occupational hazard. Based on more than two decades (1992-2012) of centralized nationwide genotyping of all Mycobacterium tuberculosis culture-positive TB patients in Denmark, we compared M. tuberculosis genotypes from all cases notified as presumed occupational (N = 130) with M. tuberculosis genotypes from all TB cases present in the country (N = 7,127). From 1992 through 2006, the IS6110 Restriction Fragment Length Polymorphism (RFLP) method was used for genotyping, whereas from 2005 to present, the 24-locus-based Mycobacterial Interspersed Repetitive Unit-Variable Number of Tandem Repeat (MIRU-VNTR) was used. An occupational TB case was classified as clustered if the genotype was 100% identical to at least one other genotype. Subsequently, based on genotype, time period, smear positivity, geography, susceptibility pattern, and any reported epidemiological links between the occupational cases and any potential source cases, the occupational case was categorized as confirmed, likely, possible or unlikely occupationally infected. Among the 130 notified presumed occupational cases, 12 (9.2%) could be classified as confirmed and 46 (35.4%) as unlikely, accounting for nearly half of all cases (44.6%). The remaining 72 cases (55.4%) were categorized as possible. Within this group, 15 cases (11.5%) were assessed to be likely occupational. Our study shows that genotyping can serve as an important tool for disentangle occupational TB in high-income low incidence settings, but still needs to be combined with good epidemiological linkage information.
Cites: Eur Respir J. 2006 Dec;28(6):1216-2116807264