SEARCH · PubMed Health

Results for “outbreak”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,639 records · Page 91Linked to original sources

PubMed1996

Investigation of a Q-fever outbreak in northern Italy.

OBJECTIVES: A study was conducted to evaluate the extent of a Q-fever epidemic through active case finding in the area of Vicenza (north-eastern Italy), and to identify risk factors for Q-fever in this outbreak. METHODS: 1) Descriptive epidemiology; 2) Seroepidemiological survey; 3) Case-control study. 1) Epidemic curve and maps with the location of cases. Identification of the road followed by the flocks of sheep. 2) Cross-sectional study on humans and flocks of sheep tested for anti-Coxiella burnetii antibodies. 3) Cases were defined by the presence of fever > 38 degrees C plus serological confirmation. Controls were 94 apparently healthy individuals attending outpatient facilities for control visits or certification, group-matched by geographical area, age and gender. A standardized questionnaire was administered by trained interviewers. Odds ratio and 95% confidence intervals (CI) were used to evaluate risk factors for Q-fever. RESULTS: A total 58 cases were identified in a 5-month period. Male to female ratio was 2.8:1; mean age was 42 years (range: 20-65 years). Twenty-eight patients (48%) were hospitalized. Fever was accompanied by asthenia (81%), headache (76%), chills (72%), and myalgia and arthralgia (53%); cough was present in 47% of patients. Rx abnormalities were found in 81% of the patients undergoing chest X-ray. Among 111 apparently healthy family members who underwent serological testing, four (3.6%) had antibodies to Coxiella burnetii. Three flocks which passed through the outbreak area between late May and early June were shown to be infected, with prevalence of antibodies ranging between 45 and 53%. The case-control study showed a significant association with exposure to flocks of sheep (Odds ratio = 6.1; 95% CI 2.5, 16.3). Other potential risk factors were not more commonly reported by cases with respect to controls. CONCLUSIONS: Indirect exposure to flocks of sheep was a determinant of this outbreak of Q-fever. This finding suggests that transmission occurred through inhalation of contaminated airborne particles. The importance of control measures should be stressed in areas traversed by flocks of sheep.

Adult↗

PubMedDate not supplied

Increased occurrence of hepatitis A with cyclic outbreaks among drug addicts in a Swedish community.

To determine the prevalence of antibodies to Hepatitis A virus (anti-HAV) among drug addicts, sera collected in a Swedish city during a ten-year period from 234 drug addicts with acute hepatitis B were tested for anti-HAV. The results were compared with the normal population, where only 3.8% of those born after 1950 were anti-HAV-positive. In individuals born between 1941 and 1965, 8.2% in the normal population and 30.2% of the drug addicts were anti-HAV-positive (p less than 0.001). The level of immunity to hepatitis A among drug addicts ranged from 7.7% to 60% during the ten-year period. Low levels of immunity were seen in the years preceeding outbreaks of hepatitis A among drug addicts. These outbreaks occurred in a cyclic pattern. Higher levels of immunity were seen after each outbreak.

Antibodies, Viral↗

PubMed1987

An outbreak of diphtheria among Swedish alcoholics.

After 25 years without any indigenous cases of diphtheria in Sweden, an outbreak occurred in the city of Göteborg, during 1984 to 1986. A group of alcoholics constituted the reservoir of Corynebacterium diphtheriae. The outbreak included 13 clinical cases and 65 carriers. The death-to-case ratio and the complication rate among the clinical cases was high, with three fatal cases and six patients developing reversible paralyses. The fatal cases had no history of previous immunization. The outbreak demonstrates the necessity of a good vaccination status to diphtheria, also in countries where the disease was thought to have been eradicated.

Adolescent↗

PubMed1995

Use of pulsed-field gel electrophoresis for investigation of an outbreak of Clostridium difficile infection among geriatric patients.

A six-month outbreak of Clostridium difficile infection among elderly residents of a middle-term-care facility was investigated. Pulsed-field gel electrophoresis was used to genotype 22 outbreak strains and 30 epidemiologically unrelated strains. A prospective case-control study was conducted to identify risk factors for epidemic Clostridium difficile-associated diarrhea. All epidemiologically unrelated Clostridium difficile strains of the same serogroup could be differentiated by their DNA patterns with two restriction enzymes (SmaI and KspI). Among clustered strains, two epidemic serogroups (C and K) were identified. Two different DNA patterns were identified among serogroup C strains and three among serogroup K strains. Multivariate analysis showed that the risk of Clostridium difficile infection increased with antimicrobial chemotherapy (beta-lactam agents and pristinamycin) and the presence of a feeding tube. This study confirms the high discriminative power of restriction fragment length polymorphism analysis by pulsed-field gel electrophoresis to describe Clostridium difficile epidemiology. The typing results confirm that infection was principally exogenous in this outbreak. Furthermore, they indicate the need to improve all measures limiting transmission of infection.

Aged↗

PubMed1997

Molecular epidemiology of an outbreak of Legionnaires' disease associated with a cooling tower in Genova-Sestri Ponente, Italy.

Fatty acid profile analysis, monoclonal antibody (MAb) subtyping, pulsed-field gel electrophoresis (PFGE), arbitrarily primed polymerase chain reaction (AP-PCR), and ribotyping were used to compare clinical and environmental Legionella pneumophila serogroup 1 isolates from an outbreak of Legionnaires' disease presumptively associated with cooling towers. According to the Oxford subtyping scheme, the MAb subtype of patients' isolates and of two strains originating from a cooling tower was Pontiac, whereas the other isolates were subtype Olda. The strains showed no intrinsic strain-to-strain difference in fatty acid profiles, and ribotyping and length polymorphism of the 16S-23S rDNA intervening regions failed to reveal any differences between the isolates. Conversely, PFGE and AP-PCR appeared to be more discriminatory, as the same genomic profile was found for the clinical and some environmental strains. Meteorologic and epidemiological data and the results of molecular analysis of the Legionella pneumophila serogroup 1 isolates support the hypothesis that the infection was transmitted from one of the cooling towers to the indoor environment of the same building, to homes in proximity that had open windows, and to the streets. In fact, the outbreak diminished and later ended after a part in the tower was replaced. This investigation demonstrates the utility of combined molecular methods (i.e., phenotypic and genomic typing) in comparing epidemiologically linked clinical and environmental isolates. Finally, the outbreak confirms the risk of Legionnaires' disease posed by cooling towers, mainly when atmospheric thermal and humidity inversions occur. This finding emphasizes the need to determine whether the source of infection is in the living or working environment or somewhere else.

Adult↗

PubMed1997

Nosocomial outbreak of Clostridium difficile diarrhea in a pediatric service.

An outbreak of nosocomial diarrhea that occurred in a pediatric orthopedic service between 1 December 1993 and 15 April 1994 is reported. A total of 37 patients (mean age, 9.6 years; range, 2 months-19.3 years) were involved in the outbreak, including six patients with bacteriologically documented Clostridium difficile infection. A multivariate analysis identified lincomycin treatment for at least three days as the only significant risk factor. Stool samples from four asymptomatic patients were also positive for Clostridium difficile and its cytotoxins. Isolates from all patients belonged to serogroup C, were highly resistant to lincomycin, and exhibited the same restriction pattern by pulsed-field gel electrophoresis. The outbreak ended after treatment with lincomycin was discontinued and hygiene control measures were implemented.

Adolescent↗

PubMed1997

Pulsed-field gel electrophoresis analysis of clonal relationships among Neisseria meningitidis A strains from different outbreaks.

Pulsed-field gel electrophoresis was used to analyze the DNA of 67 Neisseria meningitidis A strains from five African outbreaks occurring between 1988 and 1996. Endonuclease Bg/II was used to cut chromosomal DNA, generating 19 analyzable fragments. This technique allowed comparison of clonal relationships between outbreak strains and revealed that the same pulsotype was responsible for the outbreaks. This pulsotype is closely related to strain B54, subgroup III reference strain, Finland, 1975, showing only two fragment differences.

Africa↗

PubMed1997

Pseudo-outbreak of listeriosis elucidated by pulsed-field gel electrophoresis.

Listeria monocytogenes was isolated from three patients hospitalized in two departments of the same hospital over a two-week period. A nosocomial outbreak of listeriosis was suspected. Patients presented with tenosynovitis, central venous catheter infection, and bacteremia. The first patient had a community-acquired infection, the second a nosocomial infection, and the source of the third patient's illness was uncertain. Epidemiological investigations failed to identify a common source of contamination within the hospital. The three strains were nontypeable by phage typing, but Smal macrorestriction analysis and pulsed-field gel electrophoresis yielded three distinct profiles. Therefore, the three cases seemed to represent a cluster of sporadic cases as opposed to an outbreak of listeriosis. Rapid typing of isolates is essential in the early investigation of potential outbreaks of listeriosis and may prevent the initiation of expensive and time-consuming epidemiological investigations.

Aged↗

PubMedDate not supplied

Epidemiological survey of an outbreak of multiresistant Serratia marcescens by PCR-fingerprinting.

During an outbreak of Serratia marcescens from May to November 1993 43 strains obtained from 27 ICU patients infected or colonized with multiresistant S. marcescens were genotypically characterized with random amplified polymerase chain reaction (RAPD-PCR)-fingerprinting. In addition, 43 epidemiologically unrelated control isolates were selected. PCR-fingerprinting identified ten different genotypes of S. marcescens among the outbreak related strains. One predominant genotype was demonstrated in 21/43 isolates of 11/27 patients. A cluster of this genotype was found in seven/eight patients on the cardiosurgical ICU. The epidemiologically unrelated strains all showed different genotypes as compared to the predominant type. This survey proved RAPD-PCR to be a highly discriminatory and reproducible method for epidemiological studies of S. marcescens strains in nosocomial outbreaks.

Bacterial Typing Techniques↗

PubMed1995

Analysis of matrix protein gene nucleotide sequence diversity among Newcastle disease virus isolates demonstrates that recent disease outbreaks are caused by viruses of psittacine origin.

Nucleotide sequence analysis was completed for isolates of Newcastle disease virus (NDV; avian paramyxovirus 1) from 1992 outbreaks in cormorants and turkeys. These isolates were of the neurotropic velogenic type. The cormorant and turkey NDV isolates had the fusion protein cleavage sequence 109SRGRRQKR/FVG119, as opposed to the consensus sequence 109SGGRRQKR/FIG119 of most known velogenic NDV isolates. The R for G substitution at position 110 may be unique for the cormorant and turkey isolates. For comparative purposes, nucleotide sequencing and analysis of the conserved matrix protein gene coding region were completed for isolates representing all pathotypes. Phylogenetic relationships demonstrated that there are two major groups of NDV isolates. One group includes viruses found in North America and worldwide, such as B1, LaSota, Texas/GB, and Beaudette/C. The second group contains isolates, such as ulster/2C, Australia/Victoria, and Herts/33, considered exotic to North America. Within this second group are viruses of psittacine origin. The viruses from 1992 outbreaks of Newcastle disease in North America, and an isolate thought to have caused the major outbreak in southern California during the 1970s, are most closely related to an NDV isolate of psittacine origin.

Amino Acid Sequence↗

PubMedDate not supplied

First recorded outbreaks of meningococcal disease in the Israel Defence Force: three clusters due to serogroup C and the emergence of resistance to rifampicin.

Outbreaks of meningococcal disease were observed for the first time in the Israel Defence Force (I.D.F.) in 1992 and 1993, while in previous years, cases appeared in sporadic fashion. Two episodes in the winter of 1992 involving three and two individuals, respectively, were caused by Neisseria meningitidis group C, which was nontypable and nonsubtypable (C:NT:-). Three cases in one event in early 1993 were due to group C:NT:P1.2, the two secondary cases being caused by strains completely resistant to rifampicin. While these outbreaks were small, they should be seen against a background of the emergence of relatively virulent clones of serogroup C which have caused significant outbreaks in several countries. This and the drug resistance problem will require medical decision-makers to review strategies for the prevention of meningococcal disease, taking into account alternative agents for chemoprophylaxis as well as a possible role for vaccination.

Bacteremia↗

PubMed1989

Prevalence of enterotoxigenic Escherichia coli strains in outbreaks and sporadic cases of diarrhoea in Spain.

Escherichia coli strains isolated 1985-1988 in Spain from patients with diarrhoea were examined; 1170 strains were isolated from 582 sporadic cases of diarrhoea in children, and seven strains were associated with seven outbreaks of diarrhoea. Strains positive for STa enterotoxin production in the infant mouse test were also assayed for production of LT enterotoxin on Vero cells and by a coagglutination test. Thirty-one strains were STa positive: 28 were isolated from 16 (2.7%) sporadic cases of diarrhoea and three were responsible for outbreaks. The majority of STa+LT- strains from both outbreaks and sporadic cases were serotype O153:H45 and expressed the CFA/I colonization factor antigen. Enterotoxigenic STa+LT- strains of serotype O27:H7 and STa+LT+ CFA/II+ strains of serotype O6:K15:H16 were also isolated frequently from sporadic cases.

Antigens, Bacterial↗

PubMed1983

Waterborne outbreak of Campylobacter enteritis.

A report is given on an outbreak of enteritis which occurred in July 1982 in a kibbutz near Jerusalem. About 150 of the 512 inhabitants were affected. Campylobacter jejuni was isolated from ten out of 42 stool samples examined toward the end of the outbreak. No other enteric pathogen was found. Strong circumstantial evidence indicated an association between the outbreak and the use of water from an unprotected reservoir, but no bacteriological confirmation was obtained.

Adolescent↗

PubMed1987

A recent outbreak of rinderpest in East Africa.

Rinderpest was brought under control in Kenya in 1976 but in April 1986 an outbreak of the disease occurred in cattle in Western Kenya, five kilometres from the Kenya-Uganda border. This was the first confirmed field outbreak of the disease in Kenya after a lull of over 10 years. Clinical disease was confined to unvaccinated zebu calves aged six to eight months from which rinderpest virus was isolated. High titres of antibodies to rinderpest virus were demonstrated in sera collected from sheep and goats that were grazing together with the affected cattle herds; there was, however, no evidence of clinical disease in these small ruminants and wildlife species in the affected area. The disease outbreak was rapidly stamped out by quarantine and vaccination.

Africa, Eastern↗

PubMed1992

An outbreak of haemorrhagic septicaemia (septicaemic pasteurellosis) in cattle in Zimbabwe.

An outbreak of haemorrhagic septicaemia caused by Pasteurella multocida in beef cattle in Zimbabwe grazing effluent-irrigated pastures, is described. The outbreak occurred during the wet summer months and predisposing stress factors included excessive rainfall and unusual cold weather during the preceding month. History, clinical features and post-mortem findings were consistent with reports of the disease from other countries, except that meningitis was also a constant feature. Morbidity approached 77% and mortality 5 per cent. Prophylactic treatment and vaccination with a killed bacterin together with a return of warmer and drier weather were probably important in halting the outbreak.

Age Factors↗

PubMed2003

Investigation of disease outbreaks detected by "syndromic" surveillance systems.

Syndromic surveillance systems can detect potential disease outbreaks quickly and can provide useful tools to assist in outbreak investigation. The steps used to investigate diseases detected through these newer methods are not that different from traditional investigative measures, but the differences and limitations of the systems must be understood. With syndromic surveillance systems, there is often readily available electronic demographic information that can help define the epidemic and direct disease control measures. The diagnosis needs to be confirmed as quickly as possible, however, as specific diagnostic information will be missing with early detection from nonspecific data. It is also important not to disregard smaller, nonsevere rises in disease incidence as they might be a harbinger of a worsening outbreak. The rapidity of most syndromic surveillance systems also requires an equally rapid response, and planning must be done to prioritize alert categories and the response sequence to best utilize the information available in these new systems.

Bioterrorism↗

PubMed2004

Outbreak of gastric mucormycosis associated with the use of wooden tongue depressors in critically ill patients.

OBJECTIVE: To describe a nosocomial outbreak of gastric mucormycosis caused by Rhizopus microsporus var. rhizopodiformis in five adult patients admitted to an intensive care unit (ICU). DESIGN: Epidemiological surveillance study. SETTING: A 12-bed polyvalent ICU of an acute care teaching hospital in Pamplona, Spain. PATIENTS: Five patients admitted to the ICU requiring artificial ventilation, diagnosis on admission severe pneumonia in four patients and one polytrauma patient, within a 14-week period, were diagnosed with gastric mucormycosis based on microbiological and/or histopathological characteristics. Upper gastrointestinal bleeding was the presenting manifestation in 80% of patients. INTERVENTIONS: Filamentous fungi isolated at the microbiology laboratory of the hospital were examined at the national Mycology Reference Laboratory in Madrid. MEASUREMENTS AND RESULTS: Rhizopus microsporus var. rhizopodiformis growth was detected in gastric aspiration samples, environmental samples, wooden tongue depressors used to prepare oral medications (and given to patients through a nasogastric catheter), and in some tongue depressors stored in unopened boxes unexposed to the ICU environment. All depressors were purchased from the same supplier. R. microsporus was not isolated from batches purchased at different times from the same supplier and from another supplier. The outbreak terminated when contaminated tongue depressors were withdrawn from use. CONCLUSIONS: Wooden tongue depressors contaminated by R. microsporus var. rhizopodiformis used to prepare oral medications caused an outbreak of fungal gastritis with an attributable mortality of 40%. Wooden material should not be used in the hospital setting.

APACHE↗

PubMed2003

An outbreak of fulminant hepatitis B in immunocompromised hemodialysis patients.

BACKGROUND: We aimed to clarify the pathogenesis of an outbreak of fulminant hepatitis B in hemodialysis (HD) patients whose compromised cell-mediated immunity in turn contributed to chronic hepatitis B virus (HBV) carriage. METHODS: Five consecutive adult HD patients with acute hepatitis B were evaluated. Viral genotype, mutations, and HBV-DNA levels were studied in relation to viral clearance, liver disease severity, and liver histology by immunostaining. RESULTS: All five patients had hepatitis B surface antigen (HBsAg) genotype C, a G-to-A stop codon mutation at nucleotide (nt) 1896 in the precore region, an A-to-T mutation at nt 1762 and an G-to-A mutation at nt 1764 in the basal core promoter. The possible index patient, who suffered from liver cirrhosis, had HBsAg genotype C, anti-hepatitis B envelope (HBe), and these mutations. The level of HBV-DNA declined by about 10 percent per week and no difference in viral kinetics between the patients who died and the survivor was found, irrespective of therapies. The amount of liver cell apoptosis, as assessed by single-stranded DNA, was scarce. The risk of fulminant hepatic failure did not correlate with the preexistent liver histopathological changes. Acute HBV superinfection was associated with hepatitis C virus (HCV) elimination and increased mortality. CONCLUSIONS: This outbreak of fulminant hepatitis B suggests that HD patients can foster highly virulent HBV strains (possibly owing to their compromised immune responses), which may place others at risk of severe, life-threatening acute liver damage and at increased risk of mortality if chronic carriers of HCV should be infected. We aimed to clarify the pathogenesis of an outbreak of fulminant hepatitis B in hemodialysis (HD) patients whose compromised cell-mediated immunity in turn contributed to chronic hepatitis B virus (HBV) carriage.

Aged↗