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Background: Following hospitalization of the first patient with Ebola virus disease diagnosed in the United States on 28 September 2014, contact tracing methods for Ebola were implemented. Objective: To identify, risk-stratify, and monitor contacts of patients with Ebola. Design: Descriptive investigation. Setting: Dallas County, Texas, September to November 2014. Participants: Contacts of symptomatic patients with Ebola. Measurements: Contact identification, exposure risk classification, symptom development, and Ebola. Results: The investigation identified 179 contacts, 139 of whom were contacts of the index patient. Of 112 health care personnel (HCP) contacts of the index case, 22 (20%) had known unprotected exposures and 37 (30%) did not have known unprotected exposures but interacted with a patient or contaminated environment on multiple days. Transmission was confirmed in 2 HCP who had substantial interaction with the patient while wearing personal protective equipment. These HCP had 40 additional contacts. Of 20 community contacts of the index patient or the 2 HCP, 4 had high-risk exposures. Movement restrictions were extended to all 179 contacts; 7 contacts were quarantined. Seven percent (14 of 179) of contacts (1 community contact and 13 health care contacts) were evaluated for Ebola during the monitoring period. Limitation: Data cannot be used to infer whether in-person direct active monitoring is superior to active monitoring alone for early detection of symptomatic contacts. Conclusion: Contact tracing and monitoring approaches for Ebola were adapted to account for the evolving understanding of risks for unrecognized HCP transmission. HCP contacts in the United States without known unprotected exposures should be considered as having a low (but not zero) risk for Ebola and should be actively monitored for symptoms. Core challenges of contact tracing for high-consequence communicable diseases included rapid comprehensive contact identification, large-scale direct active monitoring of contacts, large-scale application of movement restrictions, and necessity of humanitarian support services to meet nonclinical needs of contacts. [ABSTRACT FROM AUTHOR]

The dengue. West Nile, Japanese encephalitis and yellow fever viruses are important mosquito-borne viruses whose epidemiology is shifting in response to changing societal factors, such as increasing commerce, urbanization of rural areas, and population growth. All four viruses are expanding geographically, as exemplified by the emergence of West Nile virus in the Americas and Japanese encephalitis virus in Australasia. The large, recent global outbreaks of severe neurological disease caused by West Nile virus, the increasing frequency of dengue hemorrhagic fever outbreaks in the Americas, and the emergence of yellow fever virus vaccination-associated viscerotropic disease, are new clinical epidemiologic trends. These worrisome epidemiologic trends will probably continue in coming decades, as a reversal of their societal and biological drivers is not in sight. Nevertheless, the substantial reductions in Japanese encephalitis virus incidence resulting from vaccination programs and economic development in some Asian countries provide some encouragement within this overall guarded outlook. [ABSTRACT FROM AUTHOR]

In January 1996, the Robert Koch Institute, Germany's national public health institute, began strengthening its epidemiologic capacity to respond to emerging and other infectious diseases. Six integrated strategies were initiated: developing employee training, outbreak investigation, and epidemiologic research programs; strengthening surveillance systems; improving communications to program partners and constituents; and building international collaborations. By December 1999, five employees had completed a 2-year applied epidemiology training program, 186 health department personnel had completed a 2-week training course, 27 outbreak investigations had been completed, eight short-term research projects had been initiated, major surveillance and epidemiologic research efforts for foodborne and nosocomial infections had begun, and 16 scientific manuscripts had been published or were in press. The German experience indicates that, with a concerted effort, considerable progress in building a national applied infectious disease program can be achieved in a short time frame. [ABSTRACT FROM AUTHOR]

For 12 hours, excess hydrofluorosilicic acid was diverted to a 127-home community water supply. Fluoride levels peaked at 51 parts per million (ppm). Water acidification caused copper to leach from the domestic plumbing; raising copper levels to 25–41 ppm. Fifty-two (33 per cent) of those who drank hyperfluoridated water developed mild gastroenteritis. Vomiting was uncommon and symptom onsets usually occurred >30 minutes after drinking water; suggesting that fluoride, rather than copper, caused illness. Skin contact with hyperfluoridated water caused itching and skin rashes. [ABSTRACT FROM AUTHOR]

Transfusion-transmitted infections have been documented for several arboviruses, including West Nile and dengue viruses (1). Zika virus, a flavivirus transmitted primarily by Aedes aegypti mosquitoes that has been identified as a cause of congenital microcephaly and other serious brain defects (2), became recognized as a potential threat to blood safety after reports from a 2013-2014 outbreak in French Polynesia. Blood safety concerns were based on very high infection incidence in the population at large during epidemics, the high percentage of persons with asymptomatic infection, the high proportion of blood donations with evidence of Zika virus nucleic acid upon retrospective testing, and an estimated 7-10-day period of viremia (3). At least one instance of transfusion transmission of Zika virus has been documented in Brazil after the virus emerged there, likely in 2014 (4). Rapid epidemic spread has followed to other areas of the Americas, including Puerto Rico. [ABSTRACT FROM AUTHOR]

The article discusses the rising cases of West Nile virus in North America. The virus was first isolated in the West Nile region of Uganda in 1937, and it gathered little medical attention until it was detected in New York in 1999. The Centers for Disease Control has collaborated with state and local health departments to establish ArboNet, an electronic surveillance system for tracking West Nile virus infections in humans, mosquitoes, birds, and other animals in the United States. The author includes statistical information on cases reported throughout the U.S., taken from ArboNet.

Discusses cases of the West Nile virus in the U.S. Two cases in New York City; Spread throughout the U.S.; Description of the virus in birds and humans; Transmission by mosquitoes and donated organs; Development of meningitis or encephalitis in patients; Diagnosis; Limitations of virus-detection assays; Importance of strengthening the linkages between health care providers and public health officials and between human and veterinary medicine and public health.