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Rebecca L Calderon

Publications and source records attributed to Rebecca L Calderon.

23 records · Page 2Linked to original sources
PubMed2003

Trends in enteric disease as a cause of death in the United States, 1989-1996.

The authors examined rates of and trends in enteric disease as a cause of death in the United States. The National Center for Health Statistics Multiple Cause of Death databases for 1989-1996 were analyzed for International Classification of Diseases, Ninth Revision, codes for gastroenteritis due to infectious agents and codes describing illness with other enteric pathogens. The highest rates of death related to enteric diseases were seen among people older than 75 years, followed by children under 1 year of age. Rates increased markedly over time in the 65- to 74-year age group for bacterial enteric pathogens and in the 35- to 44-year age group for viral enteric pathogens. Enteric diseases were the underlying cause of death for an average of 2,740 deaths during each year of this study, and the rate of death due to enteric-related disease is increasing.

Adolescent↗
PubMed2003

Health effects and risk assessment of arsenic.

Humans can be exposed to arsenic (As) through the intake of air, food and water. Although food is usually the major source of As exposure for people, most adverse effects are seen after As exposure from drinking water. The two main reasons for this situation are that most food arsenicals are organic and have little or no toxicity, and in many cases, As exposures from drinking water sources are to the more toxic inorganic form and occur at relatively high doses, e.g., hundreds of micrograms per day. In various parts of the world, As in drinking water is associated with such effects as gastroenteritis, neurological manifestations, vascular changes, diabetes and cancers (bladder, lung, liver, kidney and prostate). After reviewing the As database, the U.S. Environmental Protection Agency promulgated a maximum contaminant level for As in drinking water of 10 micro g/L.

Animals↗
PubMed2002

Surveillance for waterborne-disease outbreaks--United States, 1999-2000.

PROBLEM/CONDITION: Since 1971, CDC, the U.S. Environmental Protection Agency (EPA), and the Council of State and Territorial Epidemiologists (CSTE) have maintained a collaborative surveillance system for the occurrences and causes of waterborne-disease outbreaks (WBDOs).This surveillance system is the primary source of data concerning the scope and effects of waterborne diseases on persons in the United States. REPORTING PERIOD COVERED: This summary includes data regarding outbreaks occurring during January 1999-December 2000 and previously unreported outbreaks occurring in 1995 and 1997. DESCRIPTION OF THE SYSTEM: The surveillance system includes data for outbreaks associated with drinking water and recreational water. State, territorial, and local public health departments are primarily responsible for detecting and investigating WBDOs and voluntarily reporting them to CDC on a standard form. The unit of analysis for the WBDO surveillance system is an outbreak, not an individual case of a waterborne disease. Two criteria must be met for an event to be defined as a WBDO. First, > or = 2 persons must have experienced a similar illness after either ingestion of drinking water or exposure to water encountered in recreational or occupational settings. This criterion is waived for single cases of laboratory-confirmed primary amebic meningoencephalitis and for single cases of chemical poisoning if water-quality data indicate contamination by the chemical. Second, epidemiologic evidence must implicate water as the probable source of the illness. RESULTS: During 1999-2000, a total of 39 outbreaks associated with drinking water was reported by 25 states. Included among these 39 outbreaks was one outbreak that spanned 10 states. These 39 outbreaks caused illness among an estimated 2,068 persons and were linked to two deaths. The microbe or chemical that caused the outbreak was identified for 22 (56.4%) of the 39 outbreaks; 20 of the 22 identified outbreaks were associated with pathogens, and two were associated with chemical poisoning. Of the 17 outbreaks involving acute gastroenteritis of unknown etiology, one was a suspected chemical poisoning, and the remaining 16 were suspected as having an infectious cause. Twenty-eight (71.8%) of 39 outbreaks were linked to groundwater sources; 18 (64.3%) of these 28 groundwater outbreaks were associated with private or noncommunity wells that were not regulated by EPA. Fifty-nine outbreaks from 23 states were attributed to recreational water exposure and affected an estimated 2,093 persons. Thirty-six (61.0%) of the 59 were outbreaks involving gastroenteritis. The etiologic agent was identified in 30 (83.3%) of 36 outbreaks involving gastroenteritis. Twenty-two (61.1%) of 36 gastroenteritis-related outbreaks were associated with pools or interactive fountains. Four (6.8%) of the 59 recreational water outbreaks were attributed to single cases of primary amebic meningoencephalitis (PAM) caused by Naegleria fowleri. All four cases were fatal. Fifteen (25.4%) of the 59 outbreaks were associated with dermatitis; 12 (80.0%) of 15 were associated with hot tubs or pools. In addition, recreational water outbreaks of leptospirosis, Pontiac fever, and chemical keratitis, as well as two outbreaks of leptospirosis and Pontiac fever associated with occupational exposure were also reported to CDC. INTERPRETATION: The proportion of drinking water outbreaks associated with surface water increased from 11.8% during 1997-1998 to 17.9% in 1999-2000. The proportion of outbreaks (28) associated with groundwater sources increased 87% from the previous reporting period (15 outbreaks), and these outbreaks were primarily associated (60.7%) with consumption of untreated groundwater. Recreational water outbreaks involving gastroenteritis doubled (36 outbreaks) from the number of outbreaks reported in the previous reporting period (18 outbreaks). These outbreaks were most frequently associated with Cryptosporidium parvum (68.2%) in treated water venues (e.g., swimming pools or interactive fountains) and by Escherichia coli O157:H7 (21.4%) in freshwater venues. The increase in the number of outbreaks probably reflects improved surveillance and reporting at the local and state level as well as a true increase in the number of WBDOs. PUBLIC HEALTH ACTION: CDC and others have used surveillance data to identify the types of water systems, their deficiencies, and the etiologic agents associated with outbreaks and evaluated current technologies for providing safe drinking water and safe recreational water. Surveillance data are used also to establish research priorities, which can lead to improved water-quality regulations. Only the groundwater systems under the influence of surface water are required to disinfect their water supplies, but EPA is developing a groundwater rule that specifies when corrective action (including disinfection) is required. CDC and EPA are conducting epidemiologic studies to assess the level of waterborne illness attributable to municipal drinking water in nonoutbreak conditions. Rules under development by EPA--the Ground Water Rule (GWR), the Long Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR), and Stage 2 Disinfection Byproduct Rules (DBPR)--are expected to further protect the public from contaminants and disinfection byproducts in drinking water. Efforts by EPA under the Beaches Environmental Assessment, Closure, and Health (BEACH) program are aimed at reducing the risks for infection attributed to ambient recreational water by strengthening beach standards and testing; providing faster laboratory test methods; predicting pollution; investing in health and methods research; and improving public access to information regarding both the quality of the water at beaches and information concerning health risks associated with swimming in polluted water. EPA's Beach Watch (available at http://www.epa.gov/waterscience/beaches) provides online information regarding water quality at U.S. beaches, local protection programs, and other beach-related programs. CDC partnered with a consortium of local and national pool associations to develop a series of health communication materials for the general public who attend treated recreational water venues and to staff who work at those venues. CDC has also developed a recreational water outbreak investigation toolkit that can be used by public health professionals. All of the CDC materials are accessible at the CDC Healthy Swimming website (http://www.cdc.gov/healthyswimming).

Communicable Diseases↗
PubMed2002

Serological evidence of endemic waterborne cryptosporidium infections.

PURPOSE: Cryptosporidium oocysts are commonly detected in surface-derived drinking water, however, the public health significance of these findings is unclear. This study compared the evidence of prior Cryptosporidium infection for people drinking water derived from surface versus ground water sources. METHODS: This study measured serological responses to two Cryptosporidium antigen groups for blood donors from two midwestern United States cities with different drinking water sources: filtered and chlorinated river water receiving agricultural and domestic sewage upstream versus chlorinated water from an underground aquifer. Initial and nine-month paired serological responses to two Cryptosporidium antigen groups were compared. RESULTS: Initially, donors from the surface water city had a higher relative prevalence (RP) of a serological response (54% vs. 38%, RP = 1.39 (1.21,1.60)). Donors with a detectable baseline response who resided in the surface water city had a higher relative risk (RR) of an increased intensity of response on the follow-up blood draw (15/17-kDa, 40/100 vs. 11/100, RR = 3.78 (1.89,7.58)), (27-kDa 38/100 vs. 18/100, RR = 2.07 (1.31,3.25)). Donors with no baseline response to the 15/17-kDa marker who resided in the surface water city also had a higher risk of serconversion (38/100 vs. 14/100, RR = 2.63 (1.78,3.91)). CONCLUSIONS: These rates of both background and drinking water related Cryptosporidium infections are substantially higher than previously estimated, however, the risk of illness from infection may be lower.

Animals↗
PubMedDate not supplied

Outbreaks in drinking-water systems, 1991-1998.

During 1991-1998, 126 outbreaks, 429,021 cases of illness, 653 hospitalizations, and 58 deaths were reported in public and individual water systems in 41 states and three U.S. territories. A bacterial, viral, or protozoan etiology was identified in 41 percent of the outbreaks, and a chemical contaminant was identified in 18 percent. No etiological agent was determined in the remaining outbreaks. Important causes of outbreaks included contamination of untreated groundwater, inadequate disinfection of groundwater, and distribution system deficiencies, especially cross-connections and corrosive water. The responsible pathogen or chemical was identified in water samples collected during 31 percent of the reported outbreaks. Coliform bacteria were detected in water samples collected during the investigation of infectious-disease outbreaks in 83 percent of noncommunity and 46 percent of community water systems, but very few of these systems had exceeded the U.S. Environmental Protection Agency's maximum limit for total coliforms in the 12 months before the outbreak.

Animals↗