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PubMed2004

Norovirus outbreaks in a hospital setting: the role of infection control.

AIMS: Noroviruses (NV) (until recently known as Norwalk-like viruses) are a common cause of outbreaks of viral gastroenteritis and can result in significant hospital disruption. We report our experience of two outbreaks that occurred in a geriatric rehabilitation hospital and the role of infection control in limiting their spread. METHODS: The outbreaks occurred in two separate rehabilitation wards for older people. A case definition was developed and a register kept to record patient and staff sickness. The NV was identified from faecal specimens by reverse transcriptase polymerase chain reaction. RESULTS: There were 41 cases in the first outbreak, with an attack rate of 57.1% for patients and 41% for staff. The outbreak lasted 14 days and closed the ward for 11 days. During this outbreak one patient died, with gastroenteritis the precipitating event of his final illness. There were 24 cases in the second outbreak, with an attack rate of 56.5% for patients and 18% for staff. The outbreak lasted 16 days with the ward closed for six days. The mean duration of staff sickness was 3.5 days in the second outbreak compared with only 1.2 days in the first outbreak. In both outbreaks infection was contained within a single ward. CONCLUSIONS: NV infections can significantly disrupt hospitals through their rapid spread to patients and staff as well as the associated high attack rate. Early recognition of an outbreak and prompt implementation of infection control measures, staffing restrictions and ward closure can limit the spread of infection.

Aged↗
PubMed2000

A large rubella outbreak with spread from the workplace to the community.

CONTEXT: Childhood vaccination has reduced rubella disease to low levels in the United States, but outbreaks continue to occur. The largest outbreak in the past 5 years occurred in Nebraska in 1999. OBJECTIVES: To examine risk factors for disease, susceptibility of the risk population, role of vaccine failure, and the need for new vaccination strategies in response to the Nebraska rubella outbreak. DESIGN, SETTING, AND PATIENTS: Investigation of 83 confirmed rubella cases occurring in Douglas County, Nebraska, between March 23 and August 24, 1999; serosurvey of 413 pregnant women in the outbreak locale between October 1998 and March 1999 (prior to outbreak) and April and November 1999 (during and after outbreak). MAIN OUTCOME MEASURES: Case characteristics, compared with that of the general county population; area childhood rubella vaccination rates; and susceptibility among pregnant women before vs during and after the outbreak. RESULTS: All 83 rubella cases were unvaccinated or had unknown vaccination status and fell into 3 groups: (1) 52 (63%) were young adults (median age, 26 years), 83% of whom were born in Latin American countries where rubella vaccination was not routine. They were either employed in meatpacking plants or were their household contacts. Attack rates in the plants were high (14.4 per 1000 vs 0. 19 per 1000 for general county population); (2) 16 (19%), including 14 children (9 of whom were aged <12 months) and 2 parents, were US-born and non-Hispanic, who acquired the disease through contacts at 2 day care facilities (attack rate, 88.1 per 1000); and (3) 15 (18%) were young adults (median age, 22 years) whose major disease risk was residence in population-dense census tracts where meatpacking-related cases resided (R(2) = 0.343; P<.001); 87% of these persons were born in Latin America. Among pregnant women, susceptibility rates were 13% before the outbreak and 11% during and after the outbreak. Six (25%) of 24 susceptible women tested were seropositive for rubella IgM. Rubella vaccination rates were 90.2% for preschool children and 99.8% for school-aged children. CONCLUSIONS: A large rubella outbreak occurred among unvaccinated persons in a community with high immunity levels. Crowded working and living conditions facilitated transmission, but vaccine failure did not. Workplace vaccination could be considered to prevent similar outbreaks. JAMA. 2000;284:2733-2739.

Adolescent↗
PubMed1992

Management and epidemiologic analyses of an outbreak due to methicillin-resistant Staphylococcus aureus.

PURPOSE: Following implementation of special measures to control a nosocomial outbreak of methicillin-resistant Staphylococcus aureus (MRSA), we used immunoblot typing in conjunction with antimicrobial susceptibility testing to investigate the epidemiology of this event and to determine whether this outbreak represented the failure of infection control measures to limit the spread of previously endemic MRSA strains or the introduction of a new strain of MRSA. MATERIALS AND METHODS: Isolates of MRSA recovered from hospitalized patients were initially categorized on the basis of antimicrobial susceptibility results. Organisms susceptible to ciprofloxacin and/or trimethoprim/sulfamethoxazole were recovered from patients at a relatively constant rate prior to December 1988 and were categorized as endemic isolates. Subsequently, there was an outbreak due to organisms resistant to both of these antibiotics; these were therefore categorized as outbreak isolates. Isolates were later characterized by immunoblot typing. Prior to this analysis, isolates were given code numbers so that clinical and epidemiologic data as well as resistance patterns were not known until this testing was complete. RESULTS: Between January 1986 and November 1988, an average of 3.9 patients per month acquired nosocomial MRSA in the Sepulveda Veterans Administration Medical Center. In contrast, from December 1988 to October 1989, 369 MRSA isolates were collected from 125 patients (an average of 11.4 patients per month). Prior to December 1988, all tested nosocomial isolates of MRSA were susceptible to ciprofloxacin and/or to trimethoprim/sulfamethoxazole. In contrast, the outbreak was due to spread of MRSA isolates resistant to these antibiotics. Immunoblot typing of 204 isolates from 98 individuals identified five distinct immunoblot types of which types B and C were by far the most common. Type B was highly associated with outbreak isolates, whereas type C was associated with endemic isolates (p less than 0.001). All sequential isolates from single patients that belonged to different susceptibility categories demonstrated discordant immunoblot types. In contrast, concordant immunoblot types were observed for 25 of 27 sequential isolates that displayed minor variations in antimicrobial resistance. The institution of more stringent infection control measures was followed by the return of nosocomial MRSA acquisition rates to pre-outbreak levels. Although novobiocin and trimethoprim/sulfamethoxazole were extensively used to treat patients harboring outbreak and endemic isolates, respectively, in no instance was the initial MRSA isolate from any patient resistant to novobiocin and only 6% of initial endemic isolates displayed trimethoprim/sulfamethoxazole resistance. A modest, significant increase in the resistance of endemic isolates to various other antimicrobial agents was noted however. CONCLUSION: Immunoblot analyses provided strong, corroborative evidence that at least two separate strains of MRSA were present during the outbreak and that a newly introduced strain with a distinctive antimicrobial resistance pattern was primarily responsible for the rapid spread of MRSA during the outbreak. The observation that previously effective infection control measures failed to prevent the nosocomial spread of a newly introduced community-acquired MRSA strain suggests that a single set of control measures may not be equally efficacious against all strains of MRSA. In this regard, previously reported variations in resistance to topical antimicrobials and/or antiseptics, and differences in virulence factors such as colonization potential, invasiveness, and survival on fomites, may warrant further study. Control of the outbreak strain of MRSA in our institution did occur after the implementation of more strenuous isolation procedures.(ABSTRACT TRUNCATED)

California↗
PubMed2006

Outbreak detection through automated surveillance: a review of the determinants of detection.

Public health agencies and other groups have invested considerable resources in automated surveillance systems over the last decade. These systems generally follow syndromes in pre-diagnostic data drawn from sources such as emergency department visits. A main goal of syndromic surveillance systems is to detect outbreaks rapidly and the number of studies evaluating outbreak detection has increased recently. This paper reviews these studies with the goal of identifying the determinants of outbreak detection in automated syndromic surveillance systems. The review identified 35 studies with 22 studies (63%) relying on naturally occurring outbreaks and 13 studies (37%) relying on simulated outbreaks. In general, the results from these studies suggest that syndromic surveillance systems are capable of detecting some types of disease outbreaks rapidly with high sensitivity. The determinants of detection included characteristics of the system and of the outbreak. Influential system characteristics included representativeness, the outbreak detection algorithm, and the specificity of the algorithm. Important outbreak characteristics included the magnitude and shape of the signal and the timing of the outbreak. Future evaluations should aim to address inconsistencies in the evidence noted in this review and to identify the potential influence of other factors on outbreak detection.

Diagnosis, Computer-Assisted↗
PubMedDate not supplied

A review of outbreaks of foodborne disease associated with passenger ships: evidence for risk management.

OBJECTIVE: Foodborne disease outbreaks on ships are of concern because of their potentially serious health consequences for passengers and crew and high costs to the industry. The authors conducted a review of outbreaks of foodborne diseases associated with passenger ships in the framework of a World Health Organization project on setting guidelines for ship sanitation. METHODS: The authors reviewed data on 50 outbreaks of foodborne disease associated with passenger ships. For each outbreak, data on pathogens/toxins, type of ship, factors contributing to outbreaks, mortality and morbidity, and food vehicles were collected. RESULTS: The findings of this review show that the majority of reported outbreaks were associated with cruise ships and that almost 10,000 people were affected. Salmonella spp were most frequently associated with outbreaks. Foodborne outbreaks due to enterotoxigenic E. coli spp, Shigella spp, noroviruses (formally called Norwalk-like viruses), Vibrio spp, Staphylococcus aureus, Clostridium perfringens, Cyclospora sp, and Trichinella sp also occurred on ships. Factors associated with the outbreaks reviewed include inadequate temperature control, infected food handlers, contaminated raw ingredients, cross-contamination, inadequate heat treatment, and onshore excursions. Seafood was the most common food vehicle implicated in outbreaks. CONCLUSIONS: Many ship-associated outbreaks could have been prevented if measures had been taken to ensure adequate temperature control, avoidance of cross-contamination, reliable food sources, adequate heat treatment, and exclusion of infected food handlers from work.

Cooking↗
PubMedDate not supplied

A review of outbreaks of waterborne disease associated with ships: evidence for risk management.

OBJECTIVE: The organization of water supply to and on ships differs considerably from that of water supply on land. Risks of contamination can arise from source water at the port or during loading, storage, or distribution on the ship. The purpose of this article is to review documented outbreaks of waterborne diseases associated with passenger, cargo, fishing, and naval ships to identify contributing factors so that similar outbreaks can be prevented in the future. METHODS: The authors reviewed 21 reported outbreaks of waterborne diseases associated with ships. For each outbreak, data on pathogens/toxins, type of ship, factors contributing to outbreaks, mortality and morbidity, and remedial action are presented. RESULTS: The findings of this review show that the majority of reported outbreaks were associated with passenger ships and that more than 6,400 people were affected. Waterborne outbreaks due to Enterotoxigenic Escherichia coli, noroviruses, Salmonella spp, Shigella sp, Cryptosporidium sp, and Giardia lamblia occurred on ships. Enterotoxigenic E. coli was the pathogen most frequently associated with outbreaks. One outbreak of chemical water poisoning also occurred on a ship. Risk factors included contaminated port water, inadequate treatment, improper loading techniques, poor design and maintenance of storage tanks, ingress of contamination during repair and maintenance, cross-connections, back siphonage, and insufficient residual disinfectant. CONCLUSIONS: Waterborne disease outbreaks on ships can be prevented. The factors contributing to outbreaks emphasize the need for hygienic handling of water along the supply chain from source to consumption. A comprehensive approach to water safety on ships is essential. This may be achieved by the adoption of Water Safety Plans that cover design, construction, operation, and routine inspection and maintenance.

Communicable Disease Control↗
PubMed1992

Outbreaks of human enteric adenovirus types 40 and 41 in Houston day care centers.

OBJECTIVE: Human enteric adenovirus (EAd) types 40 and 41 cause diarrhea in young children, but little is known about their association with outbreaks of diarrhea in the child care setting. This study evaluated EAd as a cause of outbreaks of diarrhea among infants and toddlers in day care centers. DESIGN: Stool specimens were collected weekly regardless of symptoms during four periods from January 1986 to April 1991, from children 6 to 24 months of age enrolled in prospective studies of diarrhea in day care centers. All diarrhea stool specimens were tested for bacterial enteropathogens, rotavirus, and Giardia lamblia. A total of 131 outbreaks occurred during the study. No etiologic agent was identified in 77 outbreaks. Stool specimens from 75 of these 77 outbreaks and from another 21 outbreaks of diarrhea with a known cause were evaluated for EAd with a monoclonal antibody-based enzyme immunoassay. RESULTS: A total of 4402 stool specimens from 613 children from these 96 outbreaks was tested for EAd. The virus was detected in specimens collected during 10 outbreaks, 3 of which occurred in 1986, 3 in 1988, 1 in 1989, 1 in 1990, and 2 in 1991. Of 249 children, 94 (38%) in these 10 EAd outbreaks were infected with EAd. In 51 children (54%) the infection was symptomatic and in 43 (46%) it was asymptomatic. Outbreaks lasted 7 to 44 days (mean 24.5 days). Duration of EAd excretion ranged from 1 to 14 days (mean 3.9 days), with excretion occurring from 7 days (mean 2.6) before diarrhea began to 11 days (mean 5.3 days) after diarrhea stopped. CONCLUSION: Enteric adenovirus types 40 and 41 are an important cause of outbreaks of diarrhea among children attending day care centers, often involve children in more than one room, and frequently produce asymptomatic infection.

Adenovirus Infections, Human↗
PubMed1999

Experiences with vaccination and epidemiological investigations on an anthrax outbreak in Australia in 1997.

Between January and February 1997, there was a severe outbreak of anthrax on 83 properties in north-central Victoria, Australia. Vaccination was used as a major tool to control the outbreak by establishing a vaccination buffer zone 30 km by 20 km. In all, 78, 649 cattle in 457 herds were vaccinated in a three week program. In the face of the outbreak, there was a delay before vaccination was able to stop deaths. In the 10 days following vaccination 144 cases of confirmed anthrax occurred and 38 cases occurred more than 10 days after vaccination. When all cattle on at-risk properties were revaccinated in October and early November 1997, there were only two confirmed cases of anthrax in vaccinated seven and nine month old calves in the following anthrax season. Investigations into the epidemiology of the outbreak were unable to establish a single major association for the spread of the disease by flies, biting insects, carrion scavengers, wind, manufactured feed, milk factory tanker routes, veterinary visits, animal treatments, movements of personnel between farms or burning of carcases. The weather conditions in the outbreak area were part of a long dry spell with periods of high daily and night temperatures, continuing high humidity over the period and higher than normal soil temperatures. It is possible that extensive earth works in the district involving irrigated pasture renovation and water channel and drainage renovation could have disturbed old anthrax graves. It is postulated that these works released spores that were dispersed in the preceding wet winter across poorly drained areas that formed the axis for the outbreak. The earth moving renovations establishing irrigation in the area were conducted in the late 1890s, and before the occurrence of anthrax outbreaks were recorded. The axis of the outbreak was the major stock route for cattle and sheep moving from southern Victoria to northern Victoria and southern New South Wales, and undoubtedly there would have been extensive anthrax outbreaks before vaccine became available in the 1890s. In respect of other outbreaks, the events in Victoria most resembled outbreaks of anthrax recorded in the United States of America in the 1950s, 1960s and 1970s.

Animals↗
PubMed2002

Rapid public health interventions in response to an outbreak of syphilis in Los Angeles.

BACKGROUND: Despite national ambitions to eliminate syphilis, occasional outbreaks continue to occur in many areas of the United States. GOAL: The goal of the study was to describe and evaluate the public health interventions in response to an outbreak of syphilis in Los Angeles County among men who have sex with men. STUDY DESIGN: Reported cases of primary, secondary, and early latent syphilis that occurred during an outbreak period from December 1999 to September 2000 were included in the study. The outbreak components of provider awareness, active surveillance, community-based organization recruitment, media campaign, community-outreach education and screening, and a correctional facility intervention were described. Screening results were reviewed, sexually transmitted disease (STD) hotline calls were counted, and a street-intercept survey was conducted. RESULTS: A multifaceted outbreak response was initiated in March 2000. Of the 89 outbreak cases identified, 40% were detected by HIV/AIDS early intervention providers and 26% by private clinicians or health maintenance organizations. Other case identification sources included public STD clinics (10%), STD program case-management contacts (7%), mobile van screening (7%), and correctional facility screening (10%). Screening at high-risk venues detected a syphilis prevalence of <1% and an HIV prevalence of 6%. Weekly calls to the STD hotline increased 600% during the outbreak, and 80% of surveyed individuals cited the media as the source of their awareness of syphilis. CONCLUSIONS: A multifaceted outbreak response was launched to react to an outbreak of syphilis among men who have sex with men. Prompt provider awareness and a preexisting network of HIV/AIDS providers aided case detection. Although the effectiveness of the response could not be scientifically determined, the diverse components of the response were associated with a faster decline in the outbreak than would have been expected. After 3 months, 89 cases had been identified. Outbreak preparedness should include a focus on communities of men who have sex with men, because the reintroduction of syphilis in this population may threaten national efforts toward syphilis elimination.

Adult↗
PubMed1994

Communicable disease outbreaks in long day care centres in western Sydney: occurrence and risk factors.

We surveyed the directors of all 92 long day care centres in western Sydney to document the occurrence of communicable disease outbreaks during 1992 and to identify risk factors for the occurrence of these outbreaks. A total of 6092 children were enrolled at the centres, of whom 530 (8.7%) were less than 3 years old. Most centres (80.4%) reported at least one outbreak of communicable disease. Diarrhoea was the most commonly reported outbreak type (60 outbreaks), followed by conjunctivitis, head louse infestation and chicken pox (46, 44 and 24 outbreaks, respectively). Chicken pox outbreaks had the largest mean number of cases per outbreak (9.6) and the longest mean outbreak duration (4.4 weeks). Centres with a large total enrollment (50 or more children), those that were open for 12 or more hours each day and those which had commenced operating in 1990 or more recently were generally more likely to report outbreaks, particularly of diarrhoea. The vast majority of communicable disease outbreaks (92.1%) were handled by day-care staff without seeking outside assistance. Day-care centre directors may be unaware of the health services that could help them. We need to work more closely with long day care centres, and to focus preventative efforts on large centres, those open for long hours, and newly opened centres.

Chickenpox↗
PubMed1994

Application of PCR to detect Norwalk virus in fecal specimens from outbreaks of gastroenteritis.

Norwalk virus (NV) and other small round-structured viruses (SRSVs) are frequent causes of gastroenteritis outbreaks. The recent cloning and sequencing of the NV genome has made it possible to detect NV and Norwalk-related viruses from fecal specimens by reverse transcription (RT)-PCR. We applied this technique to the examination of a total of 139 fecal specimens from 19 outbreaks characterized by NV serology, including 56 samples from 7 NV outbreaks, 36 from 6 Norwalk-related virus outbreaks, and 47 from 6 outbreaks with SRSVs visualized by electron microscopy that were serologically unrelated to NV. Three primer pairs were evaluated: two pairs in the polymerase region of NV and one pair near the 3' end of the genome. When one set of primers (primer pair 51-3) from the polymerase region was used, 40% of all samples were positive by RT-PCR and specimens from the NV outbreaks were more likely to be positive (64%) than those from outbreaks associated with Norwalk-related viruses (44%) or SRSVs (8%). To determine the relationship of the outbreak strains to NV, we compared the sequences of a 145-base portion of the polymerase gene from 10 specimens obtained from five different outbreaks characterized as NV by serology. No two outbreak strains had the same sequence in this 145-base portion of the polymerase gene, and the identities of the nucleotide and amino acid sequences of these products compared with the sequences of the corresponding region of NV ranged from 62 to 79% and 69 to 90%, respectively. Because of sequence diversity in the polymerase region, the successful application of RT-PCR to investigations of outbreaks of suspected NV-associated gastroenteritis will depend on the use of either multiple primer pairs or primers made against regions of the genome that are more conserved.

Amino Acid Sequence↗
PubMed1997

Molecular epidemiology of two international sprout-borne Salmonella outbreaks.

Sprout-borne Salmonella outbreaks in Finland have increased during the last 10 years. The latest two were caused by Salmonella enterica serovar Bovismorbificans (antigenic structure 6,8:r:1,5) in 1994 and S. enterica serovar Stanley (4,5, 12:d:1,2) in 1995. In this study, the restriction fragment length polymorphism of genomic DNA after pulsed-field gel electrophoresis (PFGE) and antimicrobial resistance profiles of the outbreak and nonoutbreak strains were compared. In each separate outbreak, the PFGE patterns of the outbreak strains (40 strains of S. enterica serovar Bovismorbificans and 28 strains of S. enterica serovar Stanley) after digestion of genomic DNA with restriction enzyme XbaI were indistinguishable from each other but differed clearly from those of the nonoutbreak strains (26 strains of S. enterica serovar Bovismorbificans and 40 strains of S. enterica serovar Stanley). The restriction enzyme XhoI did not differentiate the outbreak and nonoutbreak strains. The S. enterica serovar Stanley strains associated with the outbreak also had a unique antimicrobial resistance pattern, whereas all S. enterica serovar Bovismorbificans strains, both outbreak and nonoutbreak strains, were sensitive to all antimicrobial agents tested. Thus, the molecular typing confirmed that the S. enterica serovar Bovismorbificans outbreak isolates from humans and sprout salad were identical and strongly supported the epidemiological finding that S. enterica serovar Stanley outbreak isolates also originated from contaminated alfalfa seeds. It also confirmed that the sources of similar outbreaks in Sweden in 1994 caused by S. enterica serovar Bovismorbificans and in the United States in 1995 caused by S. enterica serovar Stanley and the source of the Finnish outbreaks were common.

Disease Outbreaks↗
PubMed2006

Marburgvirus genomics and association with a large hemorrhagic fever outbreak in Angola.

In March 2005, the Centers for Disease Control and Prevention (CDC) investigated a large hemorrhagic fever (HF) outbreak in Uige Province in northern Angola, West Africa. In total, 15 initial specimens were sent to CDC, Atlanta, Ga., for testing for viruses associated with viral HFs known to be present in West Africa, including ebolavirus. Marburgvirus was also included despite the fact that the origins of all earlier outbreaks were linked directly to East Africa. Surprisingly, marburgvirus was confirmed (12 of 15 specimens) as the cause of the outbreak. The outbreak likely began in October 2004 and ended in July 2005, and it included 252 cases and 227 (90%) fatalities (report from the Ministry of Health, Republic of Angola, 2005), making it the largest Marburg HF outbreak on record. A real-time quantitative reverse transcription-PCR assay utilized and adapted during the outbreak proved to be highly sensitive and sufficiently robust for field use. Partial marburgvirus RNA sequence analysis revealed up to 21% nucleotide divergence among the previously characterized East African strains, with the most distinct being Ravn from Kenya (1987). The Angolan strain was less different ( approximately 7%) from the main group of East African marburgviruses than one might expect given the large geographic separation. To more precisely analyze the virus genetic differences between outbreaks and among viruses within the Angola outbreak itself, a total of 16 complete virus genomes were determined, including those of the virus isolates Ravn (Kenya, 1987) and 05DRC, 07DRC, and 09DRC (Democratic Republic of Congo, 1998) and the reference Angolan virus isolate (Ang1379v). In addition, complete genome sequences were obtained from RNAs extracted from 10 clinical specimens reflecting various stages of the disease and locations within the Angolan outbreak. While the marburgviruses exhibit high overall genetic diversity (up to 22%), only 6.8% nucleotide difference was found between the West African Angolan viruses and the majority of East African viruses, suggesting that the virus reservoir species in these regions are not substantially distinct. Remarkably few nucleotide differences were found among the Angolan clinical specimens (0 to 0.07%), consistent with an outbreak scenario in which a single (or rare) introduction of virus from the reservoir species into the human population was followed by person-to-person transmission with little accumulation of mutations. This is in contrast to the 1998 to 2000 marburgvirus outbreak, where evidence of several virus genetic lineages (with up to 21% divergence) and multiple virus introductions into the human population was found.

Angola↗
PubMed2006

Transmission patterns of smallpox: systematic review of natural outbreaks in Europe and North America since World War II.

BACKGROUND: Because smallpox (variola major) may be used as a biological weapon, we reviewed outbreaks in post-World War II Europe and North America in order to understand smallpox transmission patterns. METHODS: A systematic review was used to identify papers from the National Library of Medicine, Embase, Biosis, Cochrane Library, Defense Technical Information Center, WorldCat, and reference lists of included publications. Two authors reviewed selected papers for smallpox outbreaks. RESULTS: 51 relevant outbreaks were identified from 1,389 publications. The median for the effective first generation reproduction rate (initial R) was 2 (range 0-38). The majority outbreaks were small (less than 5 cases) and contained within one generation. Outbreaks with few hospitalized patients had low initial R values (median of 1) and were prolonged if not initially recognized (median of 3 generations); outbreaks with mostly hospitalized patients had higher initial R values (median 12) and were shorter (median of 3 generations). Index cases with an atypical presentation of smallpox were less likely to have been diagnosed with smallpox; outbreaks in which the index case was not correctly diagnosed were larger (median of 27.5 cases) and longer (median of 3 generations) compared to outbreaks in which the index case was correctly diagnosed (median of 3 cases and 1 generation). CONCLUSION: Patterns of spread during Smallpox outbreaks varied with circumstances, but early detection and implementation of control measures is a most important influence on the magnitude of outbreaks. The majority of outbreaks studied in Europe and North America were controlled within a few generations if detected early.

Communicable Disease Control↗
PubMed2006

Identifying outbreaks of sexually transmitted infection: who cares?

BACKGROUND: Current routine surveillance schemes for sexually transmitted infections (STIs) in the United Kingdom (UK) are not designed for outbreak identification. Recognising STI outbreaks, therefore, depends almost entirely on the alertness of health professionals. The objective of this study was to explore health professionals' knowledge of, and attitudes towards, identification and investigation of STI outbreaks in Wales. METHODS: We conducted a cross-sectional survey in Wales in June 2005, and sent a questionnaire to consultants of genitourinary medicine (GUM, n = 11), a consultant microbiologist from each laboratory (n = 14), all consultants in communicable disease control (n = 5), and to epidemiologists of the National Public Health Service (n = 4). RESULTS: 26 (76%) of 34 survey recipients responded. Of these, 17 (65%) ranked the investigation of STI outbreaks as important or very important, and 19 (73%) perceived participation in the investigation of an STI outbreak as part of their responsibility. Only six (25%) respondents had actively searched their computer system or patient records for a possible STI outbreak in the previous twelve months, and 15 (63%) had never looked for an outbreak. Of seven GUM physicians who said they had identified at least one STI outbreak, three had never informed public health authorities. CONCLUSION: Prompt identification and coordinated investigation of outbreaks, usually through a multidisciplinary outbreak control team, is central to the control of many infectious diseases. This does not appear to be the case for STIs, which we believe represents a lost opportunity to reduce transmission. Besides improved surveillance methods, a change in culture towards STI outbreaks is needed among health professionals in Wales.

Clinical Competence↗
PubMedDate not supplied

Rubella outbreaks among Hispanics in North Carolina: lessons learned from a field investigation.

OBJECTIVE: To describe the epidemiology and the lessons learned from two simultaneous, but unrelated, outbreaks of rubella in North Carolina affecting mostly Hispanic immigrants of Mexican origin. METHODS: A case and contact investigation was conducted at industrial work sites and Hispanic communities between March 26 and June 15, 1996, using both structured and informal interviews. Active surveillance was conducted at hospitals, clinical laboratories, primary care physicians' offices, local health departments, and migrant health centers to identify additional cases. Rubella specific IgM testing was performed by the North Carolina State Laboratory to confirm cases. Vaccination clinics were conducted in communities and at work sites with a large Hispanic population in affected counties to reduce the number of susceptible persons. RESULTS: Eighty-three confirmed cases of rubella were reported: 75 cases from the first outbreak and 8 from the second. The mean age of cases from both outbreaks was 24 and 20 years, respectively. Only three cases occurred among children under five years of age, two in the first outbreak and one in the second. Seventy-one (95%) cases in the first outbreak and all 8 cases in the second outbreak were Hispanics; 21 (28%) cases from the first and 3 (37%) from the second outbreak were females, and a total of 65 (78%) cases from both outbreaks were industrial workers. Six women with confirmed cases in the first outbreak were pregnant at the time of exposure. No females cases were pregnant in the second outbreak. CONCLUSIONS: The outbreaks in North Carolina confirmed the persistent susceptibility to rubella in Hispanics and persons migrating from countries where the rubella vaccine is not used for routine childhood vaccination. The ultimate goal of rubella vaccination programs is to prevent fetal infection and congenital rubella syndrome (CRS). Thus, to eliminate rubella from the United States, efforts should focus on understanding new emerging patterns of disease transmission and vaccinating susceptible adults in settings where they congregate.

Adolescent↗
PubMed2001

Analysis of outbreaks of infectious intestinal disease in Ireland: 1998 and 1999.

Surveillance of general outbreaks of infectious gastroenteritis was introduced in 1998 by the Food Safety Authority of Ireland (FSAI), in co-operation with the eight health boards. A total of 67 general outbreaks of gastroenteritis in Ireland were reported to the FSAI in 1998 and 1999. Over 1900 people were ill as a result of these outbreaks. Four percent required hospitalisation and there were two deaths. The duration of the outbreaks varied between one day and 38 days. Salmonellae (44%) and small round structured viruses (SRSV) (12%) were the most commonly reported pathogens. In 25% of the outbreaks the aetiology was unknown. The commonest settings were restaurants, hotels and take-aways, which accounted for 45% (30/67) of all outbreaks. Sixteen percent of all outbreaks occurred in hospitals and residential institutions. Over half of the outbreaks were reported to be foodborne, 63% of which were due to various serotypes of Salmonella enterica. Eggs were implicated as the vehicle of infection in 13% of all outbreaks. An infected food handler was identified in almost one third of outbreaks, although it could not be established if this had contributed directly to the outbreak.

Cross Infection↗
PubMedDate not supplied

[Reliability of plasmid profile analysis in the identification of epidemic strains of bacteria causing an outbreak of intestinal infections].

The aim of the study was to determine the plasmid profile of isolates originated from the outbreaks of gastrointestinal tract infection in the attempt to identify the outbreak strains. Plasmid profile analysis was performed on 163 isolates; 82 isolates originated from foodborne outbreakes and 81 isolates originated from waterborne outbreakes or outbreakes spread by contact. Outbreak strain was identified in 1 (10%) of 10 foodborne outbreakes and in 7 (70%) of 10 waterborne outbreakes or outbreakes spread by contact. According to the obtained results, the method of plasmid profile analysis was more reliable in the investigation of outbreaks of gastrointestinal tract infection spread by water or contact compared to the outbreakes spread by food.

Bacterial Typing Techniques↗