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PubMedDate not supplied

Newcastle disease virus isolated from recent outbreaks in Taiwan phylogenetically related to viruses (genotype VII) from recent outbreaks in western Europe.

Three major outbreaks of Newcastle disease (ND) occurred in Taiwan in the last three decades (in 1969, 1984, and 1995). Newcastle disease viruses (NDVs) isolated in the three outbreaks, together with those isolated in 1998, were sequenced between nucleotides 47 and 435 of the fusion gene. A phylogenetic tree based on sequences obtained showed that the NDV isolated in 1969 was similar to the genotype III viruses. In contrast, all isolates in 1984 and seven of the eight isolates in 1995, together with all isolates in 1998, fell into the genotype VII. These results suggest that the 1969 outbreak of ND in Taiwan was caused by the genotype III virus, whereas the 1984 and 1995 outbreaks were caused by the genotype VII viruses. To date, the genotype VII viruses have caused many outbreaks in east Asia and western Europe. We suspect that these outbreaks have constituted the fourth panzootic of ND, which is distinct from the third panzootic caused by the "pigeon PMV-1 viruses." NDV isolated in Taiwan in 1984 was the earliest isolation of the genotype VII virus.

Amino Acid Sequence↗
PubMed1995

Measles vaccination status, delay in recognizing measles outbreaks and outbreak outcome.

From July to October 1994, Mashonaland East Province in Zimbabwe experienced measles outbreaks in which 2118 cases were reported. According to routine statistics, 69 pc of these patients were previously vaccinated against measles, 22 pc were not vaccinated and 9 pc had an unknown vaccination status. The measles vaccine coverages in the nine districts of this province during the year prior to the outbreak ranged from 58 pc to 87 pc with a provincial average of 72 pc. Three hundred and fifty eight patients who came in contact with health services during one month were investigated further. The prevalence of measles related complications among vaccinated and unvaccinated patients was 18,5 pc and 51,7 pc respectively (X2 = 56,01, p < 0,001; df = 2. While no death occurred among vaccinated patients, the case fatality rate among unvaccinated patients was 27,3 pc (X2 = 45,15, p < 0,001; df = 2). The later an outbreak was recognized the longer it was likely to last and the higher the case fatality rate was (Correlation coefficient = 0,76; 95 pc CI 0,02 - 0,96). It is concluded that the Expanded Programme on Immunization in this area is not a failure and that for outbreak control measures to be effective, they have to be implemented as early as possible, preferably within one week of the onset of an outbreak. District managers should put more emphasis on the use of data by Rural Health Centre staff in order to recognize outbreaks early.

Adolescent↗
PubMed2005

The role of disease transmission and conferred immunity in outbreaks: analysis of the 1993 Cryptosporidium outbreak in Milwaukee, Wisconsin.

The authors examined two competing hypotheses regarding the cause of the 1993 Cryptosporidium outbreak in Milwaukee, Wisconsin. The first was that oocyst contamination of the drinking-water influent, coupled with a treatment plant failure, resulted in a point-source outbreak. The second was that the outbreak was the result of transmission processes that amplified the oocyst concentration in the drinking-water effluent. Analysis of the model suggested that 1) transmission directly from person to person contributed 10% (95% confidence interval: 6%, 21%) of the total cases; 2) closing the drinking-water plant prevented 19% (95% confidence interval: 17%, 21%) of the additional cases of disease that occurred compared with the scenario in which the plant had not been closed, a result primarily driven by conferred immunity that resulted in depletion of the susceptible population; and 3) the outbreak was caused by a transmission cycle due to infectious persons shedding pathogens into the sewage, environmental transport of these pathogens via Lake Michigan to the drinking-water plant, and infection of susceptible persons via exposure to drinking water. The incidence data were consistent with this hypothesis. Further simulations suggested that increasing the distance between the wastewater effluent and the drinking-water influent may have prevented the outbreak.

Animals↗
PubMed2004

[Outbreak of methicillin-resistant Staphylococcus aureus (MRSA) in the Rijnmond region: the largest outbreak in the Netherlands].

UNLABELLED: EPIDEMIC: The annual number of new MRSA isolates in the Netherlands tripled in 2002 compared with previous years. This increase was in part due to a MRSA outbreak in the Rijnmond region. The outbreak occurred in two merged hospitals and is the largest ever to occur in the Netherlands. From November 2001 till June 2003 MRSA was isolated from 381 patients and 113 hospital employees. The worst affected departments were Surgery and Internal Medicine. One MRSA strain (pulsed-field gel electroforesis (PFGE) type 16) remained initially unrecognised and was therefore able to spread unnoticed. Soon two additional epidemic MRSA strains (types 37 and 38) were discovered. DISCUSSION: Multiple factors played a role in the extent and duration of the outbreak. Because of the delayed detection and rapid spread of MRSA type 16, the outbreak grew too large once recognised to be resolved within the available infrastructure. Investments were needed at various fields, including the infection-control service and the microbiology laboratory. Employees had to be informed and motivated, and a separate MRSA ward and OPD were provided. New MRSA outbreaks occurred, despite extensive MRSA (contact) screening among patients and employees. The numbers of isolates began falling as from the beginning of 2003.

Cross Infection↗
PubMed1998

A large outbreak of cryptosporidiosis associated with a public water supply from a deep chalk borehole. Outbreak Investigation Team.

Three hundred and forty-five confirmed cases were reported in a large waterborne outbreak of cryptosporidiosis in North Thames in the spring of 1997. The descriptive epidemiology, attack rates, a case control study, and the detection of oocysts in the water suggested strongly that the outbreak was associated with drinking unboiled tap water that originated from one deep chalk borehole. The 746,000 people living in the water distribution area were advised to boil their drinking water. Investigations did not reveal how oocysts entered the borehole. This is the first published report of a cryptosporidium outbreak caused by filtered borehole water and we believe it to be the largest outbreak due to groundwater to have been reported. Borehole supplies are regarded as relatively pure sources of water and this outbreak has implications for the future monitoring and treatment of drinking water extracted from boreholes.

Adolescent↗
PubMed1978

Salmonellosis associated with homemade ice cream. An outbreak report and summary of outbreaks in the United States in 1966 to 1976.

During the period 1966 to 1976, 22 outbreaks with 292 individual cases of salmonellosis associated with the consumption of homemade ice cream were reported to the Center for Disease Control. Salmonella typhimurium accounted for 45% of the outbreaks. The source of eggs used was known in 13 outbreaks, and all were ungraded farm- or home-produced eggs, a potential source of salmonellae. In 11 outbreaks, the method of preparation was known, and in all, the ice-cream custard had not been cooked before freezing.

Adolescent↗
PubMed2006

Psychological responses of pregnant women to an infectious outbreak: a case-control study of the 2003 SARS outbreak in Hong Kong.

OBJECTIVE: The aim of the present study was to examine the behavioral and psychological responses of pregnant women during the 2003 severe acute respiratory syndrome (SARS) outbreak in Hong Kong. METHODS: Ethnographic interviews were first conducted to identify the common psychological and behavioral responses to the outbreak. This was followed by a case-control study of 235 consecutive pregnant women recruited during the SARS epidemic, and a historical cohort of 939 pregnant women recruited a year before the outbreak. Both cohorts completed standardized rating scales on depression, anxiety, and social support. RESULTS: Women in the SARS cohort adopted behavioral strategies to mitigate their risk of contracting infection. However, pregnant women tended to overestimate the risk of contracting SARS and nearly a third of the women were homebound. The anxiety level of the SARS cohort was slightly higher than that of the pre-SARS control. No statistical difference was found between the depression levels of the two cohorts. CONCLUSION: The improved social support experienced by pregnant women during SARS might have buffered the stress associated with an outbreak. However, clinicians should monitor for overestimation of infectious risk among pregnant women.

Adult↗
PubMed2006

Characterisation of a SAT-1 outbreak of foot-and-mouth disease in captive African buffalo (Syncerus caffer): clinical symptoms, genetic characterisation and phylogenetic comparison of outbreak isolates.

African buffalo (Syncerus caffer) play an important role in the maintenance of the SAT types of foot-and-mouth disease (FMD) in southern Africa. These long-term carriers mostly become sub-clinically infected, maintaining the disease and posing a threat to other susceptible wildlife and domestic species. During an unrelated bovine tuberculosis experiment using captive buffalo in the Kruger National Park (KNP), an outbreak of SAT-1 occurred and was further investigated. The clinical signs were recorded and all animals demonstrated significant weight loss and lymphopenia that lasted 100 days. In addition, the mean cell volume and mean cell haemoglobin values were significantly higher than before the outbreak started. Virus was isolated from several buffalo over a period of 167 days post infection and the molecular clock estimated to be 3 x 10(-5) nucleotide substitutions per site per day. Seven amino acid changes occurred of which four occurred in hypervariable regions previously described for SAT-1. The genetic relationship of the outbreak virus was compared to buffalo viruses previously obtained from the KNP but the phylogeny was largely unresolved, therefore the relationship of this outbreak strain to others isolated from the KNP remains unclear.

Amino Acid Sequence↗
PubMed2002

A procedure for differentiating between the intentional release of biological warfare agents and natural outbreaks of disease: its use in analyzing the tularemia outbreak in Kosovo in 1999 and 2000.

The events of 11 September and the subsequent anthrax outbreaks in the USA have opened the world's eyes to the threat posed by terrorist groups, criminal organizations and lone operators who will stop at nothing to achieve their goals. The open or covert use of pathogens and toxins as biological warfare agents can no longer be ruled out. Against this background, the appearance of an unusual disease must be studied in order to clarify whether it is a natural or artificially caused occurrence. This issue was recently raised in discussions with local representatives and relief organizations during a tularemia epidemic in Kosovo from October 1999 to May 2000. This paper will present a procedure which attempts to use certain criteria to identify or rule out the use of biological warfare agents in the event of an unusual outbreak of disease. Data and findings gathered by routine epidemiologic and microbiological studies often provide only an indirect answer to this problem. For this reason, various criteria were formulated and points allocated to represent their importance, allowing us to deduce in a semiquantitative manner the degree of possibility of an artificial genesis of outbreaks. The significance and characterization of each criterion are discussed. An analysis of the tularemia epidemic in Kosovo based on the procedure described here indicates that a deliberate release of the causative agent of tularemia, Francisella tularensis, as a biological warfare agent is doubtful. In this paper, an approach is described to discriminate between the intentional use of biological warfare agents and natural outbreaks of infectious diseases. The developed model is flexible and considers the political, military and social analysis of the crisis-afflicted region, the specific features of the pathogen, and the epidemiologic and clinical characteristics of the epidemic.

Animals↗
PubMed1998

An outbreak of multidrug-resistant tuberculosis involving HIV-infected patients of two hospitals in Milan, Italy. Italian Multidrug-Resistant Tuberculosis Outbreak Study Group.

OBJECTIVE: To describe an outbreak of multidrug-resistant tuberculosis (MDR-TB), amongst HIV-infected patients, spread from one hospital in Milan to another. DESIGN: Descriptive epidemiological investigation and molecular typing. METHODS: All cases identified by intensive case-finding were described in terms of clinical characteristics, previous nosocomial exposure to an infectious MDR-TB patient, previous stays in other institutional settings where exposure to MDR-TB could have occurred, and restriction fragment length polymorphism (RFLP) pattern. RESULTS: Between October 1991 and July 1995, 116 cases of MDR-TB were identified (85 at hospital A and 31 at hospital B). A single case patient, infected at hospital A, introduced the strain into hospital B. Eighty-two of the 92 strains available for fingerprinting revealed an identical pattern; 10 strains had unique RFLP patterns. Nosocomial exposure to an infectious MDR-TB patient was ascertained for 39 of the 56 patients with the 'outbreak' RFLP strain at hospital A (69.6%) and for 24 of the 26 patients at hospital B (92.3%). The median duration of exposure was 32 days at hospital A and 40 days at hospital B. For eight patients with the outbreak strain, exposure was determined to have probably occurred in other hospitals, in the community or in prison. CONCLUSIONS: This is the largest nosocomial outbreak of MDR-TB reported in Europe. Exposure to MDR-TB cases in other institutions caring for HIV-infected patients probably contributed to the spread of this epidemic. Strict control measures should be immediately adopted in order to prevent the spread of TB amongst HIV-infected patients in institutional settings in Europe.

AIDS-Related Opportunistic Infections↗
PubMed1999

A Streptococcus pyogenes outbreak caused by an unusual serotype of low virulence: the value of typing techniques in outbreak investigations.

OBJECTIVES: To investigate and stop the spread of an outbreak of Streptococcus pyogenes infection in a district general hospital, involving 19 patients and two nurses over a 20-day period. METHODS: All suspected persons were investigated using conventional bacteriological techniques, followed by M, T and exotoxin gene-typing of the isolates in a national reference laboratory. RESULTS: 11 patients and both nurses were associated with the acute surgical ward on one floor of the hospital. They were infected with serotype M 9/T B3264, a strain with apparently low virulence, which has not been previously associated with outbreaks. Two other patients on the same floor each had different types and there were two clusters of another S. pyogenes serotype on other floors, each involving two patients. Two (unrelated) patients yielded other types of S. pyogenes. The patients were not seriously ill but had some delay in wound healing. CONCLUSIONS: The value of typing the isolates of S. pyogenes in this outbreak was in defining which patients were involved. No added value could be ascribed to the exotoxin gene-typing results.

Adult↗
PubMed2004

An outbreak due to peanuts in their shell caused by Salmonella enterica serotypes Stanley and Newport--sharing molecular information to solve international outbreaks.

Salmonellosis is a global problem caused by the international movement of foods and high incidence in exporting countries. In September 2001, in an outbreak investigation Australia isolated Salmonella Stanley from imported peanuts, which resulted in a wider investigation in Canada, England & Wales and Scotland. Patients infected with Salmonella serotypes known to be isolated from peanuts and reported to surveillance systems were interviewed to determine exposure histories. Tagged image file format (TIFF) images of pulsed-field gel electrophoresis (PFGE) patterns of Salmonella isolates were shared electronically amongst laboratories. Laboratories tested packets of 'Brand X' peanuts from various lots and product lines. In total, 97 cases of S. Stanley and 12 cases of S. Newport infection were found. Seventy-three per cent (71/97) of S. Stanley cases were in persons of Asian ethnicity. Twenty-eight per cent of cases recalled eating Brand X peanuts and a further 13% had peanuts in their house in the previous month or had eaten Asian-style peanuts. Laboratories isolated S. Stanley, S. Newport, S. Kottbus, S. Lexington and S. Unnamed from Brand X peanuts. Isolates of S. Stanley from peanuts and human patients were indistinguishable by PFGE. This international outbreak resulted from a product originating from one country affecting several others. Rapid sharing of electronic DNA images was a crucial factor in delineating the outbreak; multinational investigations would benefit from a harmonized approach.

Adolescent↗
PubMed1999

An international outbreak of Salmonella enteritidis associated with lasagne; lessons on the need for cross-national co-operation in investigating food-borne outbreaks.

We investigated an outbreak of Salmonella enteritidis involving at least 19 British tourists returning from one hotel in another European country. A retrospective cohort study of 47 hotel guests identified lasagne as the most likely vehicle of transmission (RR 11.5; 95% CI 3.0-44.1; P < 0.0001). However, difficulties in information exchange and lack of formal mechanisms to agree on the aims of the cross-national investigation hampered efficient management of the outbreak. The factors leading to contamination of the food vehicle were not identified and therefore specific action to prevent reoccurrence could not be taken. There is need to develop protocols for cross-national investigations of outbreaks in Europe which should include specifying objectives, roles and responsibilities of investigators and control agencies, with formal reporting of the outcome of the investigation.

Cohort Studies↗
PubMed2000

[Q-fever outbreak in Dortmund in the summer of 1999. Results of an epidemiological outbreak study].

In the summer of 1999, the health department of the City of Dortmund registered an increased incidence rate of reported Q-fever-diseases. Q-fever is a zoonosis caused by the Coxiella burnetii bacterium which typically multiplies within cells. To investigate the cause of this outbreak, an investigation was initiated. Clinical and veterinary examinations, investigations of the environment and an epidemiological case-control-study were combined. Patients as well as healthy persons interviewed for comparative purposes were asked to complete a questionnaire on their habits of life and the answers compared. The results of this study show a clear connection between an exposition with sheep, dung (OR = 14.9; 95% CI: 4.9-47) and manure (OR = 18.7; 95% CI: 3.5-180) of infected sheep and the Q-fever outbreak. The study confirmed the assumption that a local sheep farm was the source of infection for the epidemic outbreak of Q-fever in the same quarter of Dortmund.

Adolescent↗
PubMed2002

Tuberculosis outbreak in a housing unit for human immunodeficiency virus-infected patients in a correctional facility: transmission risk factors and effective outbreak control.

In 1995, an outbreak of tuberculosis (TB) occurred among residents of a correctional-facility housing unit for inmates infected with human immunodeficiency virus (HIV). We isolated and treated patients who were suspected to have TB. To determine risk factors for in-prison transmission of TB, we conducted a case-control study to compare inmate case patients infected with a distinct outbreak strain of TB with control subjects who resided in the HIV unit. We identified 15 case patients during a 4-month period. Among inmates with a CD4 count of <100 cells/mm(3), case patients were more likely than control subjects to spend >/=20 hours per week in a communal day room (odds ratio, 42; P=.002) and were less likely to have a television in their single-person room (odds ratio, 0.10; P=.003). The communal day room was a likely site of transmission. Successful collaboration between the correctional system and public health departments halted the outbreak.

AIDS-Related Opportunistic Infections↗
PubMed1992

The measles outbreak in Chikuhou District, Fukuoka, Japan, 1990: correlation between herd immunity level and outbreak size.

A measles outbreak occurred in the Chikuhou district of Fukuoka, Japan from May to October 1990, during which 71 patients were cared for at the Itoda Public Hospital. Hospital records revealed a large outbreak in the adjacent town of Kanada. In order to characterize the outbreak, questionnaires were sent to all preschool-age children in Itoda (73% effective response) and in Kanada (76% effective response) requesting information about their vaccination and/or history of measles. The number of patients was 22 (4%) in Itoda and 63 (14%) in Kanada, most of these being preschoolers, while the vaccination rate was 61% and 44%, respectively. The herd immunity levels in age-specific groups were compared between the two towns. Before the epidemic, the immunity level of 1 year old children in Kanada, who showed the higher attack rate, was lower (18%) than that in Itoda (39%), while after the epidemic it rose above 60% in both towns. When we studied the correlation between the attack rate and the vaccination rate, or the number of children susceptible to measles (susceptibility rate) in each preschool, the attack rate correlated negatively with the vaccination rate (correlation coefficient [CC] = -0.818; P less than 0.01), and positively with the susceptibility rate (CC 0.860; P less than 0.01). The regressed equation on the correlation indicated that the immunity level should be more than 70% to keep the attack rate under 5% in preschools. After the epidemic, the immunity levels of all preschoolers reached above 70%.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1991

[Food-borne outbreaks of gastroenteritis caused by small round structured viruses. 1. Four outbreaks of gastroenteritis associated with oyster consumption].

Between December 9, 1988 and January 28, 1989, there were four outbreaks of acute gastroenteritis in Saitama prefecture. Eighty-two of 123 persons (67%) attending four banquets in restaurants became ill: 44 cases attending three banquets were related to eating raw oysters, and 38 attending one banquet to eating sashimi. The most common symptoms were nausea, diarrhea, abdominal cramps, and vomiting. Average incubation periods were 29 to 32 hours long. Bacteriologic analysis of stool specimens did not reveal causative agents. Small round structured viruses were detected in fecal specimens from 19 of 39 ill persons (49%) by electron microscopy. In one of four outbreaks, the formation of antibody to small round structured virus in paired serum samples was detected by western blot test. Small round structured viruses were implicated as the etiologic agents in four outbreaks of acute gastroenteritis.

Acute Disease↗
PubMed1991

How is the source of food poisoning outbreaks established? The example of three consecutive Salmonella enteritidis PT4 outbreaks linked to eggs.

Three consecutive outbreaks of Salmonella enteritidis PT4 occurred in Wales in 1989 in which epidemiological and microbiological investigation established eggs as the likely source although kitchen inspection and food preparation histories suggested other vehicles of infection. This paper examines the contribution of analytical epidemiology in attributing causation, with particular reference to those limitations which are regarded as inherent in epidemiological evidence. Such evidence, implicating eggs in the three outbreaks, fulfilled 6/7 widely accepted criteria for causation; data to assess the seventh were lacking. Collaboration between different agencies and professionals in investigating outbreaks is very important.

Disease Outbreaks↗