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Hog production takes place mostly in large concentrated animal feeding operations (CAFOs) where waste is managed by storing in lagoons prior to land application of lagoon liquid. Salmonella, including antibiotic-resistant Salmonella, have been found in the farm environment and lagoons. The objective of this research was to determine whether Salmonella resistant to clinically relevant antibiotics were present in wastewaters and surface waters from hog CAFOs. Samples of hog waste and on farm environmental waters were analysed for Salmonella, which were tested for antimicrobial susceptibility. The highest percentage of resistant isolates were found in raw waste flushed from hog houses and in lagoon wastewater; few resistant isolates were found in on-farm surface water. Resistance to sulphamethoxazole was most common, mostly in waste samples and less commonly in surface water, followed by chloramphenicol and ampicillin. No resistance to cephalosporin or fluoroquinolones was found. Resistance to clinically relevant antibiotics was commonly found in Salmonella from hog waste but was less extensive in farm surface waters. Management of wastes from hog CAFOs should be designed to further reduce the risk of human exposures resulting from environmental contamination with Salmonella. SIGNIFICANCE AND IMPACT OF THE STUDY: This study suggests antibiotic-resistant Salmonella were common in hog wastes and present in environmental waters associated with hog CAFOs. Low levels of antibiotic-resistant Salmonella in on-farm stream waters suggest surface waters could have been contaminated, potentially serving as a mechanism of off-farm transport. Since the study, there have been multiple economic, regulatory and practice changes at the federal, state and industry level. These include regulation of antibiotic use and animal waste treatment, vertical integration in the industry and changes in antibiotic use practice. This study is a useful historical baseline against which current antibiotic resistance trends can be measured., (© 2019 The Society for Applied Microbiology.)

Background: Naegleria fowleri is a thermophilic ameba found in freshwater that causes primary amebic meningoencephalitis (PAM) when it enters the nose and migrates to the brain. Patient exposure to water containing the ameba typically occurs in warm freshwater lakes and ponds during recreational water activities. In June 2016, an 18-year-old woman died of PAM after traveling to North Carolina, where she participated in rafting on an artificial whitewater river., Methods: We conducted an epidemiologic and environmental investigation to determine the water exposure that led to the death of this patient., Results: The case patient's most probable water exposure occurred while rafting on an artificial whitewater river during which she was thrown out of the raft and submerged underwater. The approximately 11.5 million gallons of water in the whitewater facility were partially filtered, subjected to ultraviolet light treatment, and occasionally chlorinated. Heavy algal growth was noted. Eleven water-related samples were collected from the facility; all were positive for N. fowleri. Of 5 samples collected from the nearby natural river, 1 sediment sample was positive for N. fowleri., Conclusions: This investigation documents a novel exposure to an artificial whitewater river as the likely exposure causing PAM in this case. Conditions in the whitewater facility (warm, turbid water with little chlorine and heavy algal growth) rendered the water treatment ineffective and provided an ideal environment for N. fowleri to thrive. The combination of natural and engineered elements at the whitewater facility created a challenging environment to control the growth of N. fowleri., (Published by Oxford University Press for the Infectious Diseases Society of America 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Background: Naegleria fowleri is a climate-sensitive, thermophilic ameba found in warm, freshwater lakes and rivers. Primary amebic meningoencephalitis (PAM), which is almost universally fatal, occurs when N. fowleri-containing water enters the nose, typically during swimming, and migrates to the brain via the olfactory nerve. In August 2013, a 4-year-old boy died of meningoencephalitis of unknown etiology in a Louisiana hospital., Methods: Clinical and environmental testing and a case investigation were initiated to determine the cause of death and to identify potential exposures., Results: Based on testing of cerebrospinal fluid and brain specimens, the child was diagnosed with PAM. His only reported water exposure was tap water; in particular, tap water that was used to supply water to a lawn water slide on which the child had played extensively prior to becoming ill. Water samples were collected from both the home and the water distribution system that supplied the home and tested; N. fowleri was identified in water samples from both the home and the water distribution system., Conclusions: This case is the first reported PAM death associated with culturable N. fowleri in tap water from a US treated drinking water system. This case occurred in the context of an expanding geographic range for PAM beyond southern states, with recent case reports from Minnesota, Kansas, and Indiana. This case also highlights the role of adequate disinfection throughout drinking water distribution systems and the importance of maintaining vigilance when operating drinking water systems using source waters with elevated temperatures., (Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Background: Naegleria fowleri is a climate-sensitive, thermophilic ameba found in the environment, including warm, freshwater lakes and rivers. Primary amebic meningoencephalitis (PAM), which is almost universally fatal, occurs when N. fowleri-containing water enters the nose, typically during swimming, and N. fowleri migrates to the brain via the olfactory nerve. In 2011, 2 adults died in Louisiana hospitals of infectious meningoencephalitis after brief illnesses., Methods: Clinical and environmental testing and case investigations were initiated to determine the cause of death and to identify the exposures., Results: Both patients had diagnoses of PAM. Their only reported water exposures were tap water used for household activities, including regular sinus irrigation with neti pots. Water samples, tap swab samples, and neti pots were collected from both households and tested; N. fowleri were identified in water samples from both homes., Conclusions: These are the first reported PAM cases in the United States associated with the presence of N. fowleri in household plumbing served by treated municipal water supplies and the first reports of PAM potentially associated with the use of a nasal irrigation device. These cases occurred in the context of an expanding geographic range for PAM beyond southern tier states with recent case reports from Minnesota, Kansas, and Virginia. These infections introduce an additional consideration for physicians recommending nasal irrigation and demonstrate the importance of using appropriate water (distilled, boiled, filtered) for nasal irrigation. Furthermore, the changing epidemiology of PAM highlights the importance of raising awareness about this disease among physicians treating persons showing meningitislike symptoms.

Background: Primary amebic meningoencephalitis (PAM), caused by the free-living ameba Naegleria fowleri, has historically been associated with warm freshwater exposures at lower latitudes of the United States. In August 2010, a Minnesota resident, aged 7 years, died of rapidly progressive meningoencephalitis after local freshwater exposures, with no history of travel outside the state. PAM was suspected on the basis of amebae observed in cerebrospinal fluid., Methods: Water and sediment samples were collected at locations where the patient swam during the 2 weeks preceding illness onset. Patient and environmental samples were tested for N. fowleri with use of culture and real-time polymerase chain reaction (PCR); isolates were genotyped. Historic local ambient temperature data were obtained., Results: N. fowleri isolated from a specimen of the patient's brain and from water and sediment samples was confirmed using PCR as N. fowleri genotype 3. Surface water temperatures at the times of collection of the positive environmental samples ranged from 22.1°C to 24.5°C. August 2010 average air temperature near the exposure site was 25°C, 3.6°C above normal and the third warmest for August in the Minneapolis area since 1891., Conclusions: This first reported case of PAM acquired in Minnesota occurred 550 miles north of the previously reported northernmost case in the Americas. Clinicians should be aware that N. fowleri-associated PAM can occur in areas at much higher latitude than previously described. Local weather patterns and long-term climate change could impact the frequency of PAM.

Background: Outbreaks of infection with hepatitis E virus (HEV) are frequently attributed to contaminated drinking water, even if direct evidence for this is lacking., Methods: We conducted several epidemiologic investigations during a large HEV infection outbreak in Uganda., Results: Of 10,535 residents, 3218 had HEV infection; of these, 2531 lived in households with >1 case. HEV was not detected in drinking water or zoonotic sources. Twenty-five percent of cases occurred > or = 8 weeks after onset of hepatitis in an index case in the household. Households with > or = 2 cases were more likely to have a member(s) who attended a funeral, had close contact with a jaundiced person, or washed hands in a common basin with others (P < .05 for all)., Conclusions: A high attack rate in households, lack of a common source of infection, and poor hygienic practices in households with > or = 2 cases suggest person-to-person transmission of HEV during this outbreak.