Cyanobacterial blooms, iron, and environmental pollutants.

Iron determines the abundance and diversity of life and controls primary production in numerous aqueous environments. Over the past decades, the availability of this metal in natural waters has decreased. Iron deficiency can apply a selective pressure on microbial aquatic communities. Each aquatic organism has their individual requirements for iron and pathways for metal acquisition, despite all having access to the common pool of iron. Cyanobacteria, a photosynthesizing bacterium that can accumulate and form so-called 'algal blooms', have evolved strategies to thrive in such iron-deficient aqueous environments where they can outcompete other organisms in iron acquisition in diverse microbial communities. Metabolic pathways for iron acquisition employed by cyanobacteria allow it to compete successfully for this essential nutrient. By competing more effectively for requisite iron, cyanobacteria can displace other species and grow to dominate the microbial population in a bloom. Aquatic resources are damaged by a diverse number of environmental pollutants that can further decrease metal availability and result in a functional deficiency of available iron. Pollutants can also increase iron demand. A pollutant-exposed microbe is compelled to acquire further metal critical to its survival. Even in pollutant-impacted waters, cyanobacteria enjoy a competitive advantage and cyanobacterial dominance can be the result. We propose that cyanobacteria have a distinct competitive advantage over many other aquatic microbes in polluted, iron-poor environments.

Geographic Variability, Seasonality, and Increase in ASPCA Animal Poison Control Center Harmful Blue-Green Algae Calls-United States and Canada, 2010-2022.

Harmful cyanobacteria (blue-green algae) exposures can cause illness or death in humans and animals. We characterized American Society for the Prevention of Cruelty to Animals (ASPCA) Animal Poison Control Center (APCC) harmful blue-green algae (HBGA) call data, compared it to a measure of harmful algal bloom public awareness, and considered its suitability as a public health information source. ASPCA APCC dog and cat "HBGA exposure" calls made 1 January 2010-31 December 2022 were included. We calculated annual HBGA call percentages and described calls (species, month, origin, exposure route). We characterized public awareness by quantifying Nexis Uni® (LexisNexis Academic; New York, NY, USA)-indexed news publications (2010-2022) pertaining to "harmful algal bloom(s)". Call percentage increased annually, from 0.005% (2010) to 0.070% (2022). Of 999 HBGA calls, 99.4% (n = 993) were dog exposures. Over 65% (n = 655) of calls were made July-September, largely from the New England (n = 154 (15.4%)) and Pacific (n = 129 (12.9.%)) geographic divisions. Oral and dermal exposures predominated (n = 956 (95.7%)). Harmful algal bloom news publications increased overall, peaking in 2019 (n = 1834). Higher call volumes in summer and in the New England and Pacific geographic divisions drove HBGA call increases; public awareness might have contributed. Dogs and humans have similar exposure routes. ASPCA APCC HBGA call data could serve as a public health information source.

Acute health effects associated with satellite-determined cyanobacterial blooms in a drinking water source in Massachusetts.

BACKGROUND: The occurrence of cyanobacterial blooms in freshwater presents a threat to human health. However, epidemiological studies on the association between cyanobacterial blooms in drinking water sources and human health outcomes are scarce. The objective of this study was to evaluate if cyanobacterial blooms were associated with increased emergency room visits for gastrointestinal (GI), respiratory and dermal illnesses. METHODS: Satellite-derived cyanobacteria cell concentrations were estimated in the source of drinking water for the Greater Boston area, during 2008-2011. Daily counts of hospital emergency room visits for GI, respiratory and dermal illnesses among drinking water recipients were obtained from an administrative record database. A two-stage model was used to analyze time-series data for an association between cyanobacterial blooms and the occurrence of illnesses. At the first stage, predictive autoregressive generalized additive models for Poisson-distributed outcomes were fitted to daily illness count data and daily predictive variables. At the second stage, residuals from the first stage models were regressed against lagged categorized cyanobacteria concentration estimates. RESULTS: The highest cyanobacteria concentration (above the 75th percentile) was associated with an additional 4.3 cases of respiratory illness (95% confidence interval: 0.7, 8.0, p = 0.02, n = 268) compared to cyanobacteria concentrations below the 50th percentile in a two-day lag. There were no significant associations between satellite derived cyanobacterial concentrations and lagged data on GI or dermal illnesses. CONCLUSION: The study demonstrated a significant positive association between satellite-derived cyanobacteria concentrations in source water and respiratory illness occurring 2 days later. Future studies will require direct measures of cyanotoxins and health effects associated with exposure to cyanobacteria-impacted drinking water sources.

Environmental risk factors associated with pulmonary isolation of nontuberculous mycobacteria, a population-based study in the southeastern United States.

The prevalence of pulmonary nontuberculous mycobacteria (NTM) disease is increasing in the United States. Associations were evaluated among residents of central North Carolina between pulmonary isolation of NTM and environmental risk factors including: surface water, drinking water source, urbanicity, and exposures to soils favorable to NTM growth. Reports of pulmonary NTM isolation from patients residing in three counties in central North Carolina during 2006-2010 were collected from clinical laboratories and from the State Laboratory of Public Health. This analysis was restricted to patients residing in single family homes with a valid residential street address and conducted at the census block level (n = 13,495 blocks). Negative binomial regression models with thin-plate spline smoothing function of geographic coordinates were applied to assess effects of census block-level environmental characteristics on pulmonary NTM isolation count. Patients (n = 507) resided in 473 (3.4%) blocks within the study area. Blocks with >20% hydric soils had 26.8% (95% confidence interval (CI): 1.8%, 58.0%), p = 0.03, higher adjusted mean patient counts compared to blocks with ≤20% hydric soil, while blocks with >50% acidic soil had 24.8% (-2.4%, 59.6%), p = 0.08 greater mean patient count compared to blocks with ≤50% acidic soil. Isolation rates varied by county after adjusting for covariates. The effects of using disinfected public water supplies vs. private wells, and of various measures of urbanicity were not significantly associated with NTM. Our results suggest that proximity to certain soil types (hydric and acidic) could be a risk factor for pulmonary NTM isolation in central North Carolina.

Surveillance for Harmful Algal Bloom Events and Associated Human and Animal Illnesses - One Health Harmful Algal Bloom System, United States, 2016-2018.

Harmful algal bloom events can result from the rapid growth, or bloom, of photosynthesizing organisms in natural bodies of fresh, brackish, and salt water. These events can be exacerbated by nutrient pollution (e.g., phosphorus) and warming waters and other climate change effects (1); have a negative impact on the health of humans, animals, and the environment; and damage local economies (2,3). U.S. harmful algal bloom events of public health concern are centered on a subset of phytoplankton: diatoms, dinoflagellates, and cyanobacteria (also called blue-green algae). CDC launched the One Health Harmful Algal Bloom System (OHHABS) in 2016 to inform efforts to prevent human and animal illnesses associated with harmful algal bloom events. A total of 18 states reported 421 harmful algal bloom events, 389 cases of human illness, and 413 cases of animal illness that occurred during 2016-2018. The majority of harmful algal bloom events occurred during May-October (413; 98%) and in freshwater bodies (377; 90%). Human and animal illnesses primarily occurred during June-September (378; 98%) and May-September (410; 100%). Gastrointestinal or generalized illness signs or symptoms were the most frequently reported (>40% of human cases and >50% of animal cases); however, multiple other signs and symptoms were reported. Surveillance data from harmful algal bloom events, exposures, and health effects provide a systematic description of these occurrences and can be used to inform control and prevention of harmful algal bloom-associated illnesses.

Outbreaks Associated with Untreated Recreational Water - California, Maine, and Minnesota, 2018-2019.

Outbreaks associated with fresh or marine (i.e., untreated) recreational water can be caused by pathogens or chemicals, including toxins. Voluntary reporting of these outbreaks to CDC's National Outbreak Reporting System (NORS) began in 2009. NORS data for 2009-2017 are finalized, and data for 2018-2019 are provisional. During 2009-2019 (as of May 13, 2020), public health officials from 31 states voluntarily reported 119 untreated recreational water-associated outbreaks, resulting at least 5,240 cases; 103 of the outbreaks (87%) started during June-August. Among the 119 outbreaks, 88 (74%) had confirmed etiologies. The leading etiologies were enteric pathogens: norovirus (19 [22%] outbreaks; 1,858 cases); Shiga toxin-producing Escherichia coli (STEC) (19 [22%]; 240), Cryptosporidium (17 [19%]; 237), and Shigella (14 [16%]; 713). This report highlights three examples of outbreaks that occurred during 2018-2019, were caused by leading etiologies (Shigella, norovirus, or STEC), and demonstrate the wide geographic distribution of such outbreaks across the United States. Detection and investigation of untreated recreational water-associated outbreaks are challenging, and the sources of these outbreaks often are not identified. Tools for controlling and preventing transmission of enteric pathogens through untreated recreational water include epidemiologic investigations, regular monitoring of water quality (i.e., testing for fecal indicator bacteria), microbial source tracking, and health policy and communications (e.g., observing beach closure signs and not swimming while ill with diarrhea).

Application of diagnostic criteria for non-tuberculous mycobacterial disease to a case series of mycobacterial-positive isolates.

The American Thoracic Society (ATS) and Infectious Diseases Society of America (IDSA) have provided guidelines to assist in the accurate diagnosis of lung disease caused by nontuberculous mycobacteria (NTM). These microbiologic, radiographic, and clinical criteria are considered equally important and all must be met to make the diagnosis of NTM lung disease. To assess the significance of the three criteria, each was evaluated for its contribution to the diagnosis of NTM lung disease in a case series. Laboratory reports of any specimen positive for NTM isolation were collected between January 1, 2006 and December 31, 2010 at a university medical center. Medical records were reviewed in detail using a standardized form. The total number of patients with a culture from any site positive for NTM was 297 while the number from respiratory specimens during the same period was 232 (78%). Samples from two of these patients also yielded M. tuberculosis complex and were excluded. While 128 of the remaining 230 patients (55.7%) in the cohort met the microbiologic criterion for diagnosis of NTM lung disease, 151 (65.6%) and 189 (78.3%) met the radiologic and clinical criteria respectively. Only 78 patients (33.9%) met all three criteria provided by the ATS/IDSA for diagnosis of NTM lung disease. This evaluation reaffirms that defining NTM lung disease using either one or two of the criteria provided by the 2007 ATS/IDSA guidelines may significantly overestimate the number of cases of NTM lung disease. Based on the experience of defining NTM lung disease in this case series, recommendations for modification of the ATS/IDSA guidelines are provided which include expansion of both radiologic patterns and the list of symptoms associated with NTM lung disease.

Emergency Department Visits for Acute Gastrointestinal Illness After a Major Water Pipe Break in 2010.

BACKGROUND: When a water pipe breaks, contaminants can enter the drinking water system and cause waterborne illnesses such as acute gastrointestinal illness. In May 2010, a major water pipe broke near Boston, MA, and a boil water order was issued to nearly two million residents. METHODS: Using a case-crossover study design, we examined the association between the water pipe break and subsequent emergency department visits for acute gastrointestinal illness. We identified cases of illness according to ICD-9-CM diagnosis codes and selected control dates 2 weeks before and after each case. We estimated the risk of visiting the emergency department during the 0-3 and 4-7 days after the water pipe break using conditional logistic regression models. RESULTS: Our analysis included 5,726 emergency department visits for acute gastrointestinal illness from 3 April 2010 to 5 June 2010. Overall, there was a 1.3-fold increased odds for visiting the emergency department for acute gastrointestinal illness during the 0-3 days after the water pipe break (odds ratio [OR] = 1.3; 95% confidence interval [CI] = 1.1, 1.4) compared with referent dates selected 2 weeks before and after. During the 4-7 days after the break, the association diminished overall (OR = 1.1; 95% CI = 0.96, 1.2). However, in communities over 12 miles from the break, the 4- to 7-day association was elevated (OR = 1.4; 95% CI = 1.1, 1.8). CONCLUSIONS: This study suggests that a major water pipe break was associated with emergency department visits for acute gastrointestinal illness, particularly during the 0-3 days after the break, when a boil water order was in effect.

Outbreaks Associated with Untreated Recreational Water - United States, 2000-2014.

Outbreaks associated with untreated recreational water can be caused by pathogens, toxins, or chemicals in fresh water (e.g., lakes, rivers) or marine water (e.g., ocean). During 2000-2014, public health officials from 35 states and Guam voluntarily reported 140 untreated recreational water-associated outbreaks to CDC. These outbreaks resulted in at least 4,958 cases of disease and two deaths. Among the 95 outbreaks with a confirmed infectious etiology, enteric pathogens caused 80 (84%); 21 (22%) were caused by norovirus, 19 (20%) by Escherichia coli, 14 (15%) by Shigella, and 12 (13%) by Cryptosporidium. Investigations of these 95 outbreaks identified 3,125 cases; 2,704 (87%) were caused by enteric pathogens, including 1,459 (47%) by norovirus, 362 (12%) by Shigella, 314 (10%) by Cryptosporidium, and 155 (5%) by E. coli. Avian schistosomes were identified as the cause in 345 (11%) of the 3,125 cases. The two deaths were in persons affected by a single outbreak (two cases) caused by Naegleria fowleri. Public parks (50 [36%]) and beaches (45 [32%]) were the leading settings associated with the 140 outbreaks. Overall, the majority of outbreaks started during June-August (113 [81%]); 65 (58%) started in July. Swimmers and parents of young swimmers can take steps to minimize the risk for exposure to pathogens, toxins, and chemicals in untreated recreational water by heeding posted advisories closing the beach to swimming; not swimming in discolored, smelly, foamy, or scummy water; not swimming while sick with diarrhea; and limiting water entering the nose when swimming in warm freshwater.

Outbreaks Associated with Treated Recreational Water - United States, 2000-2014.

Outbreaks associated with exposure to treated recreational water can be caused by pathogens or chemicals in venues such as pools, hot tubs/spas, and interactive water play venues (i.e., water playgrounds). During 2000-2014, public health officials from 46 states and Puerto Rico reported 493 outbreaks associated with treated recreational water. These outbreaks resulted in at least 27,219 cases and eight deaths. Among the 363 outbreaks with a confirmed infectious etiology, 212 (58%) were caused by Cryptosporidium (which causes predominantly gastrointestinal illness), 57 (16%) by Legionella (which causes Legionnaires' disease, a severe pneumonia, and Pontiac fever, a milder illness with flu-like symptoms), and 47 (13%) by Pseudomonas (which causes folliculitis ["hot tub rash"] and otitis externa ["swimmers' ear"]). Investigations of the 363 outbreaks identified 24,453 cases; 21,766 (89%) were caused by Cryptosporidium, 920 (4%) by Pseudomonas, and 624 (3%) by Legionella. At least six of the eight reported deaths occurred in persons affected by outbreaks caused by Legionella. Hotels were the leading setting, associated with 157 (32%) of the 493 outbreaks. Overall, the outbreaks had a bimodal temporal distribution: 275 (56%) outbreaks started during June-August and 46 (9%) in March. Assessment of trends in the annual counts of outbreaks caused by Cryptosporidium, Legionella, or Pseudomonas indicate mixed progress in preventing transmission. Pathogens able to evade chlorine inactivation have become leading outbreak etiologies. The consequent outbreak and case counts and mortality underscore the utility of CDC's Model Aquatic Health Code (https://www.cdc.gov/mahc) to prevent outbreaks associated with treated recreational water.

Sanitary Sewer Overflows and Emergency Room Visits for Gastrointestinal Illness: Analysis of Massachusetts Data, 2006-2007.

BACKGROUND: Sanitary sewer overflows (SSOs) occur when untreated sewage is discharged into water sources before reaching the treatment facility, potentially contaminating the water source with gastrointestinal pathogens. OBJECTIVES: The objective of this paper is to assess associations between SSO events and rates of gastrointestinal (GI) illness in Massachusetts. METHODS: A case-crossover study design was used to investigate association between SSO events and emergency room (ER) visits with a primary diagnosis of gastrointestinal (GI) illness in Massachusetts for 2006-2007. ER visits for GI were considered exposed if an SSO event occurred in the county of residence within three hazard periods, 0-4 d, 5-9 d, or 10-14 d, before the visit. A time-stratified bidirectional design was used to select control days for each ER visit on the same day of the week during the same month. Fixed effect logistic regression models were used to estimate the risk of ER visits following the SSO event. RESULTS: During the study period, there were 270 SSO events for northeastern Massachusetts and 66,460 ER admissions with GI illness listed as the primary diagnostic code. The overall odds ratio (OR) for ER visits for GI illness was 1.09 [95% confidence interval (CI): 1.03, 1.16] in the 10-14 d period following an SSO event, with positive ORs for all age groups and for three of the four counties. The 0-4 d and 5-9 d periods following an SSO event were not associated with ER visits for GI illness overall, and associations by county or age were inconsistent. CONCLUSIONS: We demonstrated an association between SSO events and ER visits for GI illness using a case-crossover study design. In light of the aging water infrastructure in the United States and the expected increase in heavy rainfall events, our findings suggest a potential health impact associated with sewage overflows. https://doi.org/10.1289/EHP2048.

Erratum: "Sanitary Sewer Overflows and Emergency Room Visits for Gastrointestinal Illness: Analysis of Massachusetts Data, 2006-2007".

[This corrects the article DOI: 10.1289/EHP2048.].

Waterborne Disease Outbreaks Associated With Environmental and Undetermined Exposures to Water - United States, 2013-2014.

Waterborne disease outbreaks in the United States are associated with a wide variety of water exposures and are reported annually to CDC on a voluntary basis by state and territorial health departments through the National Outbreak Reporting System (NORS). A majority of outbreaks arise from exposure to drinking water (1) or recreational water (2), whereas others are caused by an environmental exposure to water or an undetermined exposure to water. During 2013-2014, 15 outbreaks associated with an environmental exposure to water and 12 outbreaks with an undetermined exposure to water were reported, resulting in at least 289 cases of illness, 108 hospitalizations, and 17 deaths. Legionella was responsible for 63% of the outbreaks, 94% of hospitalizations, and all deaths. Outbreaks were also caused by Cryptosporidium, Pseudomonas, and Giardia, including six outbreaks of giardiasis caused by ingestion of water from a river, stream, or spring. Water management programs can effectively prevent outbreaks caused by environmental exposure to water from human-made water systems, while proper point-of-use treatment of water can prevent outbreaks caused by ingestion of water from natural water systems.

Surveillance for Waterborne Disease Outbreaks Associated with Drinking Water - United States, 2013-2014.

Provision of safe water in the United States is vital to protecting public health (1). Public health agencies in the U.S. states and territories* report information on waterborne disease outbreaks to CDC through the National Outbreak Reporting System (NORS) (https://www.cdc.gov/healthywater/surveillance/index.html). During 2013-2014, 42 drinking water-associated† outbreaks were reported, accounting for at least 1,006 cases of illness, 124 hospitalizations, and 13 deaths. Legionella was associated with 57% of these outbreaks and all of the deaths. Sixty-nine percent of the reported illnesses occurred in four outbreaks in which the etiology was determined to be either a chemical or toxin or the parasite Cryptosporidium. Drinking water contamination events can cause disruptions in water service, large impacts on public health, and persistent community concern about drinking water quality. Effective water treatment and regulations can protect public drinking water supplies in the United States, and rapid detection, identification of the cause, and response to illness reports can reduce the transmission of infectious pathogens and harmful chemicals and toxins.

Extreme precipitation and emergency room visits for influenza in Massachusetts: a case-crossover analysis.

BACKGROUND: Influenza peaks during the wintertime in temperate regions and during the annual rainy season in tropical regions - however reasons for the observed differences in disease ecology are poorly understood. We hypothesize that episodes of extreme precipitation also result in increased influenza in the Northeastern United States, but this association is not readily apparent, as no defined 'rainy season' occurs. Our objective was to evaluate the association between extreme precipitation (≥ 99th percentile) events and risk of emergency room (ER) visit for influenza in Massachusetts during 2002-2008. METHODS: A case-crossover analysis of extreme precipitation events and influenza ER visits was conducted using hospital administrative data including patient town of residence, date of visit, age, sex, and associated diagnostic codes. Daily precipitation estimates were generated for each town based upon data from the National Oceanic and Atmospheric Administration. Odds ratio (OR) and 95% confidence intervals (CI) for associations between extreme precipitation and ER visits for influenza were estimated using conditional logistic regression. RESULTS: Extreme precipitation events were associated with an OR = 1.23 (95%CI: 1.16, 1.30) for ER visits for influenza at lag days 0-6. There was significant effect modification by race, with the strongest association observed among Blacks (OR = 1.48 (1.30, 1.68)). CONCLUSIONS: We observed a positive association between extreme precipitation events and ER visits for influenza, particularly among Blacks. Our results suggest that influenza is associated with extreme precipitation in a temperate area; this association could be a result of disease ecology, behavioral changes such as indoor crowding, or both. Extreme precipitation events are expected to increase in the Northeastern United States as climate change progresses. Additional research exploring the basis of this association can inform potential interventions for extreme weather events and influenza transmission.

Indices of iron homeostasis correlate with airway obstruction in an NHANES III cohort.

Cigarette smoking results in the accumulation of iron both systemically and locally, in the lung thereby causing imbalance in iron homeostasis. This disruption in iron homeostasis can be associated with oxidative stress and consequent tissue injury. Therefore, in this study, we tested the association between iron homeostasis and airway obstruction by examining a large cohort of smokers and non-smokers for relationships between 1) serum ferritin and iron concentrations and transferrin saturation and 2) forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), and their ratio (FEV1/FVC). Data from the National Health and Examination Survey III were analyzed. The study population included persons aged 20 years and above with their following data recorded: race, gender, serum ferritin and iron concentrations, and transferrin saturation; the final sample number was 7,251. In the total population, Pearson correlation coefficients between 1) serum ferritin and iron concentrations and transferrin saturation and 2) FVC and FEV1 were significantly positive; whereas those between 1) serum ferritin concentrations and transferrin saturation and 2) FEV1/FVC were significantly negative. With separate analyses, serum ferritin concentrations demonstrated positive associations with FVC and FEV1 but an inverse relationship with FEV1/FVC in smokers and non-smokers. Serum ferritin levels increased with worsening airway obstruction among smokers, and its highest concentrations were found among those with the lowest values of FEV1/FVC ratio (<60%). Comparable to cigarette smokers, serum ferritin concentrations among non-smokers were greatest in those with the lowest FEV1/FVC ratio. Furthermore, elevated levels of serum iron and saturation of transferrin also corresponded with decreased FEV1/FVC ratio among non-smokers. Thus, we conclude that indices of iron homeostasis are associated with airway obstruction in both smokers and non-smokers.

The Association between Dust Storms and Daily Non-Accidental Mortality in the United States, 1993-2005.

BACKGROUND: The impact of dust storms on human health has been studied in the context of Asian, Saharan, Arabian, and Australian storms, but there has been no recent population-level epidemiological research on the dust storms in North America. The relevance of dust storms to public health is likely to increase as extreme weather events are predicted to become more frequent with anticipated changes in climate through the 21st century. OBJECTIVES: We examined the association between dust storms and county-level non-accidental mortality in the United States from 1993 through 2005. METHODS: Dust storm incidence data, including date and approximate location, are taken from the U.S. National Weather Service storm database. County-level mortality data for the years 1993-2005 were acquired from the National Center for Health Statistics. Distributed lag conditional logistic regression models under a time-stratified case-crossover design were used to study the relationship between dust storms and daily mortality counts over the whole United States and in Arizona and California specifically. End points included total non-accidental mortality and three mortality subgroups (cardiovascular, respiratory, and other non-accidental). RESULTS: We estimated that for the United States as a whole, total non-accidental mortality increased by 7.4% (95% CI: 1.6, 13.5; p = 0.011) and 6.7% (95% CI: 1.1, 12.6; p = 0.018) at 2- and 3-day lags, respectively, and by an average of 2.7% (95% CI: 0.4, 5.1; p = 0.023) over lags 0-5 compared with referent days. Significant associations with non-accidental mortality were estimated for California (lag 2 and 0-5 day) and Arizona (lag 3), for cardiovascular mortality in the United States (lag 2) and Arizona (lag 3), and for other non-accidental mortality in California (lags 1-3 and 0-5). CONCLUSIONS: Dust storms are associated with increases in lagged non-accidental and cardiovascular mortality. Citation: Crooks JL, Cascio WE, Percy MS, Reyes J, Neas LM, Hilborn ED. 2016. The association between dust storms and daily non-accidental mortality in the United States, 1993-2005. Environ Health Perspect 124:1735-1743; http://dx.doi.org/10.1289/EHP216.

Epidemiology of nontuberculous mycobacteria isolations among central North Carolina residents, 2006-2010.

BACKGROUND: Nontuberculous mycobacteria (NTM) are environmental mycobacteria associated with a range of infections. Reports of NTM epidemiology have primarily focused on pulmonary infections and isolations, however extrapulmonary infections of the skin, soft tissues and sterile sites are less frequently described. METHODS: We comprehensively reviewed laboratory reports of NTM isolation from North Carolina residents of three counties during 2006-2010. We describe age, gender, and race of patients, and anatomic site of isolation for NTM species. RESULTS: Among 1033 patients, overall NTM isolation prevalence was 15.9/100,000 persons (13.7/100,000 excluding Mycobacterium gordonae). Prevalence was similar between genders and increased significantly with age. Extrapulmonary isolations among middle-aged black males and pulmonary isolations among elderly white females were most frequently detected. Most isolations from pulmonary sites and blood cultures were Mycobacterium avium complex; rapidly growing NTM (e.g. Mycobacterium chelonae, Mycobacterium fortuitum) were most often isolated from paranasal sinuses, wounds and skin. CONCLUSIONS: We provide the first characterization of NTM isolation prevalence in the Southeastern United States (U.S.). Variation in isolation prevalence among counties and races likely represent differences in detection, demographics and risk factors. Further characterization of NTM epidemiology is increasingly important as percentages of immunocompromised individuals and the elderly increase in the U.S.

Cyanotoxins in inland lakes of the United States: Occurrence and potential recreational health risks in the EPA National Lakes Assessment 2007.

A large nation-wide survey of cyanotoxins (1161 lakes) in the United States (U.S.) was conducted during the EPA National Lakes Assessment 2007. Cyanotoxin data were compared with cyanobacteria abundance- and chlorophyll-based World Health Organization (WHO) thresholds and mouse toxicity data to evaluate potential recreational risks. Cylindrospermopsins, microcystins, and saxitoxins were detected (ELISA) in 4.0, 32, and 7.7% of samples with mean concentrations of 0.56, 3.0, and 0.061µg/L, respectively (detections only). Co-occurrence of the three cyanotoxin classes was rare (0.32%) when at least one toxin was detected. Cyanobacteria were present and dominant in 98 and 76% of samples, respectively. Potential anatoxin-, cylindrospermopsin-, microcystin-, and saxitoxin-producing cyanobacteria occurred in 81, 67, 95, and 79% of samples, respectively. Anatoxin-a and nodularin-R were detected (LC/MS/MS) in 15 and 3.7% samples (n=27). The WHO moderate and high risk thresholds for microcystins, cyanobacteria abundance, and total chlorophyll were exceeded in 1.1, 27, and 44% of samples, respectively. Complete agreement by all three WHO microcystin metrics occurred in 27% of samples. This suggests that WHO microcystin metrics based on total chlorophyll and cyanobacterial abundance can overestimate microcystin risk when compared to WHO microcystin thresholds. The lack of parity among the WHO thresholds was expected since chlorophyll is common amongst all phytoplankton and not all cyanobacteria produce microcystins.