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PubMed1999

Management of a measles outbreak among Old World nonhuman primates.

BACKGROUND AND PURPOSE: A measles outbreak in a facility housing Old World nonhuman primates developed over a 2-month period in 1996, providing an opportunity to study the epidemiology of this highly infectious disease in an animal-handling setting. METHODS: Serum and urine specimens were collected from monkeys housed in the room where the initial measles cases were identified, other monkeys with suspicious measles-like signs, and employees working in the affected areas. Serum specimens were tested for measles virus-specific IgG and IgM antibodies, and urine specimens were tested for measles virus by virus isolation or reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: A total of 94 monkeys in two separate facilities had evidence of an acute measles infection. The outbreak was caused by a wild-type virus that had been associated with recent human cases of acute measles in the United States; however, an investigation was unable to identify the original source of the outbreak. Quarantine and massive vaccination helped to control further spread of infection. CONCLUSIONS: Results emphasize the value of having a measles control plan in place that includes a preventive measles vaccination program involving human and nonhuman primates to decrease the likelihood of a facility outbreak.

Animals↗

PubMedDate not supplied

[Food poisoning outbreaks: an epidemiological study].

The occurrence of foodborne disease outbreaks (FDO) is increasing in industrialized countries. Most of these outbreaks (2/3) are notified from restaurants and other commercial establishments but more and more from households. Salmonella is the major agent of FDO, especially S. enteritidis for five years. However, its role may be overestimated because inadequate microbiological techniques routinely performed. Despite recent progress, several outbreaks still go unnoticed. Every outbreak should be early investigated, with methodical collection of clinical, bacteriological and food data, followed by statistical analysis. Once identified the responsible pathogen, the contaminated food, the source of contamination and the bacterial growth enhancing factors, rapid control measures can prevent further epidemics. Compulsory notification of all FDO to the public health services is the condition for the reliability of a national surveillance programme.

Foodborne Diseases↗

PubMed2004

Re-emergence of El Tor vibrio in outbreak of cholera in & around Nagpur.

Contrary to earlier outbreaks of cholera due to Vibrio cholerae O139 during 1993 and its reemergence in 1998 in and around Nagpur and only sporadic episodes thereafter for next couple of years, a large outbreak was encountered between June and October 2003. V. cholerae 01 El Tor were isolated in 198 cases, of which 152 were Ogawa, 3 Inaba, 4 Hikojima and 39 were non agglutinating (NAG) vibrios. No isolate of V. cholerae O139 was detected during the entire outbreak. The isolates were multi drug resistant to antibiotic susceptibility tests. This points to the resurgence of V. cholerae El Tor Ogawa causing outbreaks of cholera with a discernible increase in the incidence of multi drug resistant strains.

Cholera↗

PubMedDate not supplied

Simultaneous nosocomial and community outbreak of epidemic keratoconjunctivitis with types 8 and 19 adenovirus.

In a simultaneous community and nosocomial (hospital-based) epidemic of keratoconjunctivitis lasting one year, 97 patients had clinical findings characteristic of EKC. Seventy-one percent of the cases were confirmed by laboratory tests including viral isolation, antibody response detected by complement fixation and hemagglutination inhibition tests, or immunofluorescent detection of adenovirus antigen in conjunctival scrapings. The community epidemic was a mixed adenovirus type 19 and type 8 outbreak. The nosocomial outbreak was due primarily to adenovirus type 8 (91%). The epidemiologic data of the nosocomial epidemic were representative of the population involved. The community outbreak was primarily in young individuals between 11 and 40 years of age. The secondary household attack rates were 20% and essentially were equal in both epidemics. The primary mode of spread in the nosocomial outbreak was by contamination of the examiner's fingers. In the community epidemic the mode of spread was believed to be close personal contact in a young and active age group.

Adenoviridae Infections↗

PubMed1979

Proliferative hemorrhagic enteropathy in swine: an outbreak and review of the literature.

An account is given of an acute outbreak of hemorrhagic enteric disease in 34 young adult boars of primarily Yorkshire breeding at a performance testing station in Western Canada. Two of the boars died. A diagnosis of proliferative hemorrhagic enteropathy was made on the basis of clinical signs, gross necropsy and histopathological lesions. Campylobacter-like bacteria were seen in the apical cytoplasm of epithelial cells of the ileal mucosa by Warthin-Faulkner stain on histological sections, but were not isolated on culture. Treatment with several drugs simultaneously was associated with termination of the outbreak, but the therapeutic effect was not controlled by leaving some animals untreated. Reported sequelae, such as porcine intestinal adenomatosis, were not present at necropsy or slaughter of pigs surviving the outbreak, but all were killed no longer than two months after the first case was observed. This outbreak is discussed in the context of previously reported hemorrhagic enteric conditions of pigs.

Anemia↗

PubMed1984

Outbreaks of alimentary bacterial infections reported in CSR between 1979 and 1982.

Outbreaks of alimentary infections of bacterial origin (dg 002--typhoid or paratyphoid fever; dg 003--infections due to other Salmonella species; dg 004--bacillary dysentery; dg 005--alimentary intoxications; dg 008--intestinal infections due to other bacteria; dg 009--intestinal infections of unknown etiology) which had been reported in the Czech socialist republic from 1979 to 1982 are overviewed and analyzed. The outbreaks of alimentary infections were analyzed by the number of epidemic episodes reported annually, by the number of cases involved, by the geographical and seasonal distribution pattern, by the place of onset, and by the mode of spread of infectious agents. Hospital-related salmonelloses were further analyzed by the serotype of Salmonellae responsible for these nosocomial infections. Outbreaks of water-borne alimentary infections were analyzed by the type of contaminated water source. Changes and trends in the epidemiology of alimentary bacterial infections encountered between 1979 and 1982 are discussed in detail. This study confirms that a systematic analysis of these outbreaks should constitute an integral part of the alimentary infections surveillance program for it may help assess the risk of population exposure to the varied causes of these infections.

Bacterial Infections↗

PubMedDate not supplied

[Characteristics of the epidemic process in enterovirus infections in relation to the study of a serous meningitis outbreak].

The etiological investigation of an epidemic outbreak of aseptic meningitis occuring in 1978 in Khabarovsk was performed. The leading etiological agent was found to be ECHO-4 virus. Some of the cases were associated with ECHO-20 and Coxsackie B1 viruses. Investigation of the herd immunity to these viruses in the urban population showed that before the outbreak the immune portion to ECHO-4 and ECHO-20 viruses was low, particularly in children and youngsters. This might be due to the fact that active circulation of these viruses and outbreaks of diseases associated with them had occurred 13--15 years before. The immune portion to enteroviruses in different towns of the Far East was shown to be uneven. The results of investigations of the epidemic outbreak and herd immunity permit to consider it to be a typical manifestation of the cyclic circulation of enteroviruses in the territory and in time.

Adolescent↗

PubMed1993

Pleurodynia among football players at a high school. An outbreak associated with coxsackievirus B1.

OBJECTIVE: Enteroviral outbreaks involving athletic teams have been described, although the mode of transmission has been unclear. In September 1991, an outbreak of pleurodynia among high school football players provided an opportunity to identify possible modes of transmission. DESIGN: Retrospective cohort outbreak investigation. SETTING: Public high school in upstate New York. RESULTS: Illness was reported by 17 (20%) of the football players. Behaviors involving contact with common water containers were associated with illness, including eating ice cubes from the team ice chest (relative risk [RR], 9.2; 95% confidence interval [CI], 1.3 to 65.5) and drinking water from the team cooler (RR, 6.3; 95% CI, 1.5 to 25.7). Coxsackievirus B1 was isolated in four (50%) of the eight stool specimens collected. CONCLUSIONS: Contamination of common water containers by an infected player may have contributed to or initiated the outbreak. In addition to discouraging direct oral contact with common drinking containers, use of individual water containers and ice packs for injuries was recommended.

Adolescent↗

PubMed2026

Emerging hantavirus risks in mass gatherings: epidemiology, diagnostic challenges, and outbreak preparedness.

Hantaviruses are emerging rodent borne zoonotic pathogens of increasing global public health concern because of their high mortality, expanding ecological distribution, and potential for international dissemination. Although traditionally associated with sporadic rural outbreaks, recent ecological disruption, climate variability, urbanization, and increased global mobility have heightened concerns regarding hantavirus risks in mass gathering settings. This review critically examines the epidemiology, transmission uncertainty, diagnostic and surveillance challenges, and preparedness strategies related to hantavirus infections in the context of mass gatherings, including religious events, refugee settlements, cruise tourism, sporting events, and temporary accommodations. Particular emphasis is placed on the 2026 multinational cruise ship associated outbreak linked to the MV Hondius, which highlighted vulnerabilities related to delayed diagnosis, international passenger dispersal, and uncertainties surrounding possible human to human transmission of Andes virus. Current evidence indicates that hantavirus transmission occurs primarily through inhalation of aerosolized rodent excreta; however, controversies regarding limited interpersonal transmission, environmental persistence, and asymptomatic infections continue to complicate risk assessment and outbreak preparedness. Diagnostic limitations, underreporting, insufficient environmental surveillance, and lack of mass gathering specific preparedness frameworks remain major public health challenges, especially in resource limited settings. Strengthening proactive preparedness through integrated One Health approaches, ecological surveillance, genomic monitoring, AI driven epidemic intelligence, and coordinated international response systems is essential for mitigating future risks. The review emphasizes the urgent need for multidisciplinary research and evidence based policy development to improve global preparedness against emerging hantavirus associated threats in increasingly interconnected mass gathering environments.

Humans↗

PubMed2003

Large summertime influenza A outbreak among tourists in Alaska and the Yukon Territory.

We investigated a large summertime outbreak of acute respiratory illness during May-September 1998 in Alaska and the Yukon Territory, Canada. Surveillance for acute respiratory illness (ARI), influenza-like illness (ILI), and pneumonia conducted at 31 hospital, clinic, and cruise ship infirmary sites identified 5361 cases of ARI (including 2864 cases of ILI [53%] and 171 cases of pneumonia [3.2%]) occurring primarily in tourists and tourism workers (from 18 and 37 countries, respectively). Influenza A viruses were isolated from 41 of 210 patients with ILI at 8 of 14 land sites and 8 of 17 cruise ship infirmaries. Twenty-two influenza isolates were antigenically characterized, and all were influenza A/Sydney/05/97-like (H3N2) viruses. No other predominant pathogens were identified. We estimated that >33,000 cases of ARI might have occurred during this protracted outbreak, which was attributed primarily to influenza A/Sydney/05/97-like (H3N2) viruses. Modern travel patterns may facilitate similar outbreaks, indicating the need for increased awareness about influenza by health care providers and travelers and the desirability of year-round influenza surveillance in some regions.

Adolescent↗

PubMed2026

First year of ongoing invasive Haemophilus influenzae type b outbreak among middle-aged people who use drugs and people who experience homelessness in Hamburg, Germany, September 2024 to August 2025.

We report an ongoing outbreak of invasive Haemophilus influenzae type b (Hib) disease among people who use drugs (PWUD) and people experiencing homelessness (PEH) in Hamburg, Germany. Between 1 September 2024 and 31 August 2025, 20 adult Hib cases were reported. The cases were either residents of Hamburg (16/20) or stayed in Hamburg during the exposure period (4/20). Whole genome sequencing identified a link between 18 cases (median age 50 years (range 26-77); six female, 12 male, three died). An epidemiological link (i.e. drug consumption in the open drug scene) could be established for 15 of the 18 cases. Control measures included post-exposure chemoprophylaxis for close contacts (n = 4), vaccination offers (n = 69 doses administered by 31 August 2025) and an information campaign targeting PWUD, PEH and staff members of addiction support centres. We describe the first Hib outbreak among adults in Europe and document drug use and homelessness as suspected risk factors. Based on these findings, national vaccination recommendations issued by the Standing Committee on Vaccination in Germany (STIKO) were updated to include vaccination and post-exposure prophylaxis recommendations in outbreak settings for PWUD and PEH. Control measures are currently being evaluated and expanded.

Humans↗

PubMed2026

Genomic and Epidemiologic Insights into Ongoing Measles Outbreak, Israel, 2025-2026.

An ongoing measles outbreak in Israel, involving ≈3,200 cases and 16 deaths, threatens the country's measles elimination status and reflects declining vaccination rates observed globally and within Israel. Epidemiologic investigations supported by sequencing suggest that a single importation triggered the outbreak, underscoring the critical role of rapid genomic surveillance in outbreak control.

Measles↗

PubMed2003

Investigation of a nosocomial outbreak of severe acute respiratory syndrome (SARS) in Toronto, Canada.

BACKGROUND: Severe acute respiratory syndrome (SARS) was introduced into Canada by a visitor to Hong Kong who returned to Toronto on Feb. 23, 2003. Transmission to a family member who was later admitted to a community hospital in Toronto led to a large nosocomial outbreak. In this report we summarize the preliminary results of the epidemiological investigation into the transmission of SARS between 128 cases associated with this hospital outbreak. METHODS: We collected epidemiologic data on 128 probable and suspect cases of SARS associated with the hospital outbreak, including those who became infected in hospital and the next generation of illness arising among their contacts. Incubation periods were calculated based on cases with a single known exposure. Transmission chains from the index family to hospital contacts and within the hospital were mapped. Attack rates were calculated for nurses in 3 hospital wards where transmission occurred. RESULTS: The cases ranged in age from 21 months to 86 years; 60.2% were female. Seventeen deaths were reported (case-fatality rate 13.3%). Of the identified cases, 36.7% were hospital staff. Other cases were household or social contacts of SARS cases (29.6%), hospital patients (14.1%), visitors (14.1%) or other health care workers (5.5%). Of the 128 cases, 120 (93.8%) had documented contact with a SARS case or with a ward where there was a known SARS case. The remaining 8 cases without documented exposure are believed to have had exposure to an unidentified case and remain under investigation. The attack rates among nurses who worked in the emergency department, intensive care unit and coronary care unit ranged from 10.3% to 60.0%. Based on 42 of the 128 cases with a single known contact with a SARS case, the mean incubation period was 5 days (range 2 to 10 days). INTERPRETATION: Evidence to date suggests that SARS is a severe respiratory illness spread mainly by respiratory droplets. There has been no evidence of further transmission within the hospital after the elapse of 2 full incubation periods (20 days).

Adolescent↗

PubMed1997

Spook house sporotrichosis. A point-source outbreak of sporotrichosis associated with hay bale props in a Halloween haunted-house.

While isolated cases of sporotrichosis typically occur following contact with contaminated plant materials, outbreaks are distinctly unusual. A temporal increase in the incidence of sporotrichosis in a dermatology practice at a military installation in southwestern Oklahoma prompted an investigation. Patients with sporotrichosis presenting to a single dermatologist in the winter of 1992-1993 were interviewed, epidemiological data were collected, and fungal cultures were obtained from incriminated hay fields. Five patients presented with cutaneous sporotrichosis during a 5-week period beginning in December 1992. Four patients had maintained hay bales in a Halloween haunted house and the fifth patient had visited the house once. As in 3 previous reports, this outbreak was associated with stored hay or hay bales harvested in the US plains states. Contact with hay should be recognized as a risk factor for infection with Sporothrix schenckii. Outbreaks are possible given adequate intensity of exposure and may be difficult to recognize because of the delayed presentation of clinical illness.

Adult↗

PubMedDate not supplied

Outbreak of catheter-associated Klebsiella oxytoca and Enterobacter cloacae bloodstream infections in an oncology chemotherapy center.

BACKGROUND: In March 2004, the Chicago Department of Public Health was notified of a cluster of bloodstream infections with Klebsiella oxytoca and Enterobacter cloacae at a chemotherapy center. Our purpose was to identify the source of the outbreak and prevent further cases. METHODS: The investigation included 103 oncology patients seen at an outpatient oncology chemotherapy center in Chicago during the 16 days before its closure. The outbreak investigation included case identification, retrospective cohort study, review of medical records, microbiologic testing of blood specimens, environmental cultures, and pulsed-field gel electrophoresis. The main outcome measure was infection with K oxytoca, E cloacae, or both, and the Mantel-Haenszel chi(2) test was used to assess risk of infection in relation to presence of central venous catheter. RESULTS: Among the 103 patients, risk of infection was associated with the presence of central venous catheter (relative risk undefined, P<.001). Twenty-seven patients had blood cultures that grew K oxytoca, E cloacae, or both, and all had central venous catheters that were flushed with isotonic sodium chloride solution at the clinic from February 17 through March 3, 2004. Isolates of K oxytoca and E cloacae were matched by pulsed-field gel electrophoresis to K oxytoca and E cloacae isolates obtained from multiple predrawn syringes and from the intravenous fluid and administration set in use in the clinic at the time of its closing. CONCLUSIONS: The injection of contaminated isotonic sodium chloride solution through the venous catheters of attendees at the clinic likely provided the opportunity for bloodstream infections in these 27 case patients. This outbreak highlights the need for continued emphasis on safe injection practices and suggests the need for guidelines and recommendations tailored to outpatient settings.

Adult↗

PubMed1995

An outbreak of Norwalk virus gastroenteritis associated with eating raw oysters. Implications for maintaining safe oyster beds.

OBJECTIVE: To determine the characteristics and the cause of an outbreak of gastroenteritis associated with eating raw oysters. DESIGN: Survey of groups of persons reporting illness to the health department after eating oysters; survey of convenience sample of oyster harvesters; and tracing of implicated oysters. SETTING: General community. MAIN OUTCOME MEASURES: Relative risk for illness after oyster consumption, source bed of contaminated oysters, presence of antibodies to Norwalk virus in serum, presence of a Norwalk virus in stool by direct electron microscopy and reverse transcription-polymerase chain reaction (RT-PCR), and DNA sequences of RT-PCR products. RESULTS: Seventy (83%) of 84 persons who ate raw oysters became ill vs three (7%) of 43 people who did not eat raw oysters (relative risk, 11.9; 95% confidence interval, 4.0 to 34.2). Eleven (79%) of 14 serum pairs had at least a fourfold increase in antibody to Norwalk virus. All 12 stool samples tested were positive by electron microscopy and/or RT-PCR for Norwalk virus. The RT-PCR products from all seven stool samples tested had identical DNA sequences. Implicated oysters were harvested November 9 through 13, 1993, from a remote oyster bed. Crews from 22 (85%) of 26 oyster harvesting boats working in this area reported routine overboard disposal of sewage. One harvester with a high level of antibodies to Norwalk virus reported having gastroenteritis November 7 through 10 and overboard disposal of feces into the oyster bed. CONCLUSIONS: This outbreak was caused by contamination of oysters in the oyster bed, probably by stool from one or more ill harvesters. Education of oyster harvesters and enforcement of regulations governing waste disposal by oyster harvesting boats might prevent similar outbreaks.

Adolescent↗

PubMed1999

Outbreak of type A botulism and development of a botulism surveillance and antitoxin release system in Argentina.

CONTEXT: Botulism is an important public health problem in Argentina, but obtaining antitoxin rapidly has been difficult because global supplies are limited. In January 1998, a botulism outbreak occurred in Buenos Aires. OBJECTIVES: To determine the source of the outbreak, improve botulism surveillance, and establish an antitoxin supply and release system in Argentina. DESIGN, SETTING, AND PARTICIPANTS: Cohort study in January 1998 of 21 drivers of a specific bus route in urban Buenos Aires. MAIN OUTCOME MEASURE: Occurrence of botulism and implication of a particular food as the vehicle causing this outbreak. RESULTS: Nine (43%) of 21 bus drivers developed botulism, presenting with gastroenteritis, symptoms of acute cranial nerve dysfunction including ptosis, dysphagia, blurred vision, and motor weakness. One driver experienced respiratory failure. Type A toxin was detected from 3 of 9 patients' serum samples. All drivers received botulism antitoxin; there were no fatalities. Consumption of matambre (Argentine meat roll) was significantly associated with illness. Among 11 persons who ate matambre, 9 developed illness, compared with none of those who did not eat it (P<.001). The matambre had been cooked in water at 78 degrees C to 80 degrees C for 4 hours, sealed in heat-shrinked plastic wrap, and stored in refrigerators that did not cool adequately. Subsequently, a botulism surveillance and antitoxin release system was established. CONCLUSIONS: Insufficient cooking time and temperatures, storage in heat-shrinked plastic wrap, and inadequate refrigeration likely contributed to Clostridium botulinum spore survival, germination, and toxin production. A rapid-response botulism surveillance and antitoxin release system in Argentina should provide more timely distribution of antitoxin to patients and may serve as a model for other nations.

Adult↗

PubMed2000

Tracing a syphilis outbreak through cyberspace.

CONTEXT: A recent outbreak of syphilis among users of an Internet chat room challenged traditional methods of partner notification and community education because locating information on sexual partners was limited to screen names and privacy concerns precluded identifying sexual partners through the Internet service provider. OBJECTIVES: To determine the association of Internet use and acquisition of syphilis and to describe innovative methods of partner notification in cyberspace. DESIGN, SETTING, AND PATIENTS: Outbreak investigation conducted at the San Francisco (Calif) Department of Public Health (SFDPH) in June-August 1999 of 7 cases of early syphilis among gay men linked to an online chat room; case-control study of 6 gay men with syphilis reported to SFDPH in July-August 1999 (cases) and 32 gay men without syphilis who presented to a city clinic in April-July 1999 (controls). MAIN OUTCOME MEASURES: Association of syphilis infection with Internet use, Internet use among cases vs controls, and partner notification methods and partner evaluation indexes. RESULTS: During the outbreak, cases were significantly more likely than controls to have met their sexual partners through use of the Internet (67% vs 19%; odds ratio, 8.7; P =.03). We notified and confirmed testing for 42% of named partners; the mean number of sexual partners medically evaluated per index case was 5.9. CONCLUSIONS: In this study, meeting sexual partners through the Internet was associated with acquisition of syphilis among gay men. Public health efforts must continually adapt disease control procedures to new venues, carefully weighing the rights to privacy vs the need to protect public health. JAMA. 2000;284:447-449

Adult↗