A fresh look at the SarcoFluor antibody test for the detection of specific antibodies to Sarcocystis neurona for the diagnosis of equine protozoal myeloencephalitis.

Equine protozoal myeloencephalitis (EPM) is a challenging disease to diagnose in horses with neurological signs. To optimize contemporary diagnostic testing, including the use of serum:CSF antibody ratios, the SarcoFluor antibody test for Sarcocystis neurona requires revalidation. The SarcoFluor, a previously validated immunofluorescent antibody test (IFAT) for the detection of antibodies specific to S. neurona in serum and cerebrospinal fluid (CSF) of naturally infected horses was analyzed using recent data and considering a serum:CSF antibody ratio threshold. Utilization of serum and CSF phosphorylated neurofilament heavy protein (pNfH) concentrations in support of an EPM diagnosis was also evaluated. 172 horses were divided into three groups: EPM-positive horses (EPM+, n=42), neurological non-EPM horses (n=74) confirmed with non-EPM neurological diseases (cervical vertebral compressive myelopathy, equine neuroaxonal dystrophy/equine degenerative myeloencephalopathy), and control horses (control, n=56) without neurological signs and neurological abnormalities on histology. Logistic regression was used to compare EPM diagnostic regimens. Specifically, EPM+ horses were compared with neurological non-EPM horses showing neurological signs. To consider diagnostic utility, post-test probabilities were calculated by titer. When differentiating between EPM and other neurological diseases, the combination of serum and CSF SarcoFluor testing added more information to the model accuracy than either test alone. Using serum and CSF for pNfH in support of an EPM diagnosis did not identify cutoffs with statistically significant odds ratios but increased the overall model accuracy when used with the IFAT. Utilization of IFAT titers against S. neurona in serum and CSF result in a high post-test probability of detecting EPM+ horses in a clinical setting.

Evidence of intrathecally-derived antibodies against Toxoplasma gondii in horses suspected of neurological disease consistent with equine protozoal myeloencephalitis.

Among the recognized neurologic diseases in horses, equine protozoal myeloencephalitis (EPM) has been reported around the world and still presents challenges in diagnosis and treatment. Horses can present with clinical neurologic signs consistent with EPM while testing negative for the two main causative agents, Sarcocystis neurona or Neospora hughesi, and may still be clinically responsive to anti-parasitic drug therapy. This context led to our hypothesis that another protozoal parasite, Toxoplasma gondii, which is known to cause toxoplasmosis in other mammalian species, is a potential pathogen to cause neurologic disease in horses. To evaluate this hypothesis, serum and cerebrospinal fluid (CSF) were collected from 210 horses presenting with clinical signs compatible with EPM, and the indirect immunofluorescent antibody test (IFAT) was used to detect antibody titers for T. gondii, S. neurona, and N. hughesi. Additionally, the serum to CSF titer ratio was calculated for T. gondii, S. neurona, and N. hughesi infections, suggesting intrathecally-derived antibodies for each of the three agents if the serum:CSF ratio was ≤ 64. There were 133 (63.3%) horses positive for serum T. gondii antibodies using a cutoff titer of 160, and 31 (14.8%) positive for CSF T. gondii antibodies using a cutoff titer of 5. Overall, 21 (10.0%) of EPM-suspect horses had a serum:CSF ratio ≤ 64 for antibodies for T. gondii, while 43 (20.5%) and 8 (3.8%) horses had a serum to CSF ratio ≤ 64 for antibodies for S. neurona and N. hughesi, respectively. A total of 6 (2.9%) animals presented evidence of concurrent intrathecally-derived antibodies for T. gondii and at least one other apicomplexan parasite in this study. Signalment and clinical signs were not different across the groups aforementioned. These data provide evidence of intrathecal production of anti-T. gondii antibodies, indicative of T. gondii infection in the brain and/or spinal cord of horses with EPM-like disease.

Assessment of Physician Knowledge, Attitudes, and Practice for Lyme Disease in a Low-Incidence State.

Lyme disease (LD), caused by the bacterium Borrelia burgdorferi, is transmitted to humans in California through the bite of infected blacklegged ticks (Ixodes pacificus). Overall, the incidence of LD in California is low: approximately 0.2 confirmed cases per 100,000 population. However, California's unique ecological diversity results in wide variation in local risk, including regions with local foci at elevated risk of human disease. The diagnosis of LD can be challenging in California because the prior probability of infection for individual patients is generally low. Combined with nonspecific symptoms and complicated laboratory testing, California physicians need a high level of awareness of LD in California to recognize and diagnose LD efficiently. This research addresses an under-studied area of physicians' knowledge and practice of the testing and treatment of LD in a low-incidence state. We assessed knowledge and practices related to LD diagnosis using an electronic survey distributed to physicians practicing in California through mixed sampling methods. Overall, responding physicians in California had a general awareness of Lyme disease and were knowledgeable regarding diagnosis and treatment. However, we found that physicians in California could benefit from further education to improve test-ordering practices, test interpretation, and awareness of California's disease ecology with elevated levels of focal endemicity, to improve recognition, diagnosis, and treatment of LD in California patients.

Therapeutics prior to mesenchymal stromal cell therapy improves outcome in equine orthopedic injuries.

OBJECTIVE: Mesenchymal stromal (stem) cells (MSCs) have been studied to treat many common orthopedic injuries in horses. However, there is limited information available on when and how to use this treatment effectively. The aim of this retrospective study is to report case features, treatment protocols, and clinical outcomes in horses treated with MSCs. ANIMALS: 65 horses presenting with tendinous, ligamentous, and articular injuries, and treated with MSCs prepared by a single laboratory between 2016 and 2019. Outcome information was available for 26 horses. PROCEDURES: Signalment, clinical signs, diagnostic methods, treatment protocol features (prior and concurrent therapies, cell origin, dose, application site and number), and effective outcomes were analyzed. The analysis was focused on comparing the effect of different MSC treatment protocols (eg, autologous vs allogeneic) on outcome rather than the effectiveness of MSC treatment. RESULTS: MSC treatment resulted in 59.1% (clinical lameness) to 76.9% (imaging structure) improvement in horses with diverse ages, breeds, sex, and lesions. The use of other therapeutic methods before MSC application (eg, anti-inflammatories, shockwave, laser, icing, resting, bandage and stack wrap, intra-articular injections, and/or surgical debridement) was shown to be statistically more effective compared to MSCs used as the primary therapeutic procedure (P < .05). Autologous versus allogeneic treatment outcomes were not significantly different. CLINICAL RELEVANCE: A prospective MSC treatment study with standardization and controls to evaluate the different features of MSC treatment protocols is needed. The various case presentations and treatment protocols evaluated can be used to inform practitioners who are currently using MSCs in clinical practice.

Coronavirus and Paramyxovirus Shedding by Bats in a Cave and Buildings in Ethiopia.

Bats are important hosts of zoonotic viruses with pandemic potential, including filoviruses, MERS-Coronavirus (CoV), SARS-CoV -1, and likely SARS-CoV-2. Viral infection and transmission among wildlife are dependent on a combination of factors that include host ecology and immunology, life history traits, roosting habitats, biogeography, and external stressors. Between 2016 and 2018, four species of insectivorous bats from a readily accessed roadside cave and buildings in Ethiopia were sampled and tested for viruses using consensus PCR assays for five viral families/genera. Previously identified and novel coronaviruses and paramyxoviruses were identified in 99 of the 589 sampled bats. Bats sampled from the cave site were more likely to test positive for a CoV than bats sampled from buildings; viral shedding was more common in the wet season; and rectal swabs were the most common sample type to test positive. A previously undescribed alphacoronavirus was detected in two bat species from different taxonomic families, sampling interfaces, geographic locations, and years. These findings expand knowledge of the range and diversity of coronaviruses and paramyxoviruses in insectivorous bats in Ethiopia and reinforce that an improved understanding of viral diversity and species-specific shedding dynamics is important for designing informed zoonotic disease surveillance and spillover risk reduction efforts.

Genetics and pathology associated with Klebsiella pneumoniae and Klebsiella spp. isolates from North American Pacific coastal marine mammals.

Southern sea otters (SSO: Enhydra lutris nereis) are a federally-listed threatened subspecies found almost exclusively in California, USA. Despite their zoonotic potential and lack of host specificity, K. pneumoniae and Klebsiella spp. have largely unknown epizootiology in SSOs. Klebsiella pneumoniae is occasionally isolated at necropsy, but not from live SSOs. Hypermucoviscous (HMV) K. pneumoniae strains are confirmed pathogens of Pacific Basin pinnipeds, but have not been previously isolated from SSOs. We characterized the virulence profiles of K. pneumoniae isolates from necropsied SSOs, evaluated killing of marine mammal K. pneumoniae following in vitro exposure to California sea lion (CSL: Zalophanus californianus) whole blood and serum, and characterized lesion patterns associated with Klebsiella spp. infection in SSOs. Four of 15 SSO K. pneumoniae isolates were HMV and all were recovered from SSOs that stranded during 2005. Many K. pneumoniae infections were associated with moderate to severe pathology as a cause of death or sequela. All HMV infections were assessed as a primary cause of death or as a direct result of the primary cause of death. Klebsiella-infected SSOs exhibited bronchopneumonia, tracheobronchitis and/or pleuritis, enteritis, Profilicollis sp. acanthocephalan peritonitis, septic peritonitis, and septicemia. All SSO HMV isolates were capsular type K2, the serotype most associated with HMV infections in CSLs. Multiplex PCR revealed two distinct virulence gene profiles within HMV isolates and two within non-HMV isolates. In vitro experiments investigating CSL whole blood and serum killing of K. pneumoniae suggest that HMV isolates are more resistant to serum killing than non-HMV isolates.

Associations between faecal pathogen detection, E. coli concentrations and youth exhibitor biosecurity practices at California county fairs.

Interactions with livestock in public settings such as county and state fairs can expose people and other livestock to faecal material capable of spreading zoonotic enteric pathogens. The goal of this study was to understand these risks by screening livestock faeces (n = 245) and livestock bedding (n = 155) for common zoonotic pathogens (Giardia, Cryptosporidium, Salmonella and Campylobacter spp.) and by measuring faecal indicator, Escherichia coli, concentrations in drinking water (n = 153), feed containers (n = 124) and bedding material (n = 157) in four livestock species (cattle, sheep, goats and swine) from county fairs in California, USA. Results indicated that sheep were most likely to have pathogens detected in faeces and that Giardia was the most frequently detected pathogen in both faeces (11%) and bedding (21%) across all livestock species. Additionally, increasing the number of animals in a holding pen at fairs, increasing the stocking density of animals in transport trailers to fairs, and having access to water in transport trailers significantly increased the odds of detecting pathogens in livestock faeces of any animal species. Observing solid material in water, stale feed and soiled bedding was associated with detecting higher E. coli concentrations. These findings provide evidence of faecal pathogens present at county fairs and suggest that site observations can aid in assessing levels of faecal exposure. The findings also indicate that the use of biosecurity measures such as (a) routine changing of livestock drinking water, feed and bedding, (b) not overstocking animals in holding pens and trailers and (c) keeping species in separate holding areas may reduce the risk of humans and livestock being exposed to faecal pathogens.

Molecular detection of Sarcocystis neurona in cerebrospinal fluid from 210 horses with suspected neurologic disease.

An ante-mortem diagnosis of equine protozoal myeloencephalitis (EPM) is presently based on clinical presentation, immunodiagnostics performed on serum and cerebrospinal fluid (CSF), and ruling out other neurological disorders. Molecular techniques introduce a novel and promising approach for the detection of protozoal agents in CSF. Hypothesizing that real-time PCR (rtPCR) can be a useful complement to EPM diagnostics, 210 CSF samples from horses suspected of neurological disease with EPM included as a differential diagnosis were tested using rtPCR to detect Sarcocystis neurona DNA and immunodiagnostics targeting antibodies against the same pathogen, performed on serum and CSF samples. Molecular and immunological results were compared with respect to origin of the horse, time of the year, signalment, clinical signs and treatment history. Twenty-five horses tested positive in CSF for S. neurona by rtPCR only, while 30 horses had intrathecally-derived antibodies to S. neurona only (serum to CSF ratio ≤ 64 by indirect fluorescent antibody test - IFAT), and 13 horses tested rtPCR-positive in CSF with evidence of intrathecally-derived antibodies to S. neurona. Previous treatment for EPM was the only variable presenting statistical difference between the two testing modalities, highlighting that animals with history of anti-protozoal treatment were more likely to test positive solely in IFAT, while horses without treatment were more likely to test positive by rtPCR only. The results support the use of molecular diagnosis for EPM caused by S. neurona as a complement to immunodiagnostics. The use of rtPCR in CSF for the detection of S. neurona may improve the diagnostic work-up of neurologic disease suspected horses, especially in animals without previous anti-protozoal treatment.

Borrelia burgdorferi and Borrelia miyamotoi seroprevalence in California blood donors.

The western blacklegged tick, Ixodes pacificus, an important vector in the western United States of two zoonotic spirochetes: Borrelia burgdorferi (also called Borreliella burgdorferi), causing Lyme disease, and Borrelia miyamotoi, causing a relapsing fever-type illness. Human cases of Lyme disease are well-documented in California, with increased risk in the north coastal areas and western slopes of the Sierra Nevada range. Despite the established presence of B. miyamotoi in the human-biting I. pacificus tick in California, clinical cases with this spirochete have not been well studied. To assess exposure to B. burgdorferi and B. miyamotoi in California, and to address the hypothesis that B. miyamotoi exposure in humans is similar in geographic range to B. burgdorferi, 1,700 blood donor sera from California were tested for antibodies to both pathogens. Sampling was from high endemic and low endemic counties for Lyme disease in California. All sera were screened using the C6 ELISA. All C6 positive and equivocal samples and nine randomly chosen C6 negative samples were further analyzed for B. burgdorferi antibody using IgG western blot and a modified two ELISA test system and for B. miyamotoi antibody using the GlpQ ELISA and B. miyamotoi whole cell sonicate western blot. Of the 1,700 samples tested in series, eight tested positive for antibodies to B. burgdorferi (0.47%, Exact 95% CI: 0.20, 0.93) and two tested positive for antibodies to B. miyamotoi (0.12%, Exact 95% CI: 0.01, 0.42). There was no statistically significant difference in seroprevalence for either pathogen between high and low Lyme disease endemic counties. Our results confirm a low frequency of Lyme disease and an even lower frequency of B. miyamotoi exposure among adult blood donors in California; however, our findings reinforce public health messaging that there is risk of infection by these emerging diseases in the state.

Utility of the Rose Bengal Test as a Point-of-Care Test for Human Brucellosis in Endemic African Settings: A Systematic Review.

In endemic African areas, such as Tanzania, Brucella spp. cause human febrile illnesses, which often go unrecognized and misdiagnosed, resulting in delayed diagnosis, underdiagnosis, and underreporting. Although rapid and affordable point-of-care tests, such as the Rose Bengal test (RBT), are available, acceptance and adoption of these tests at the national level are hindered by a lack of local diagnostic performance data. To address this need, evidence on the diagnostic performance of RBT as a human brucellosis point-of-care test was reviewed. The review was initially focused on studies conducted in Tanzania but was later extended to worldwide because few relevant studies from Tanzania were identified. Databases including Web of Science, Embase, MEDLINE, and World Health Organization Global Index Medicus were searched for studies assessing the diagnostic performance of RBT (sensitivity and specificity) for detection of human brucellosis, in comparison to the reference standard culture. Sixteen eligible studies were identified and reviewed following screening. The diagnostic sensitivity (DSe) and specificity (DSp) of RBT compared to culture as the gold standard were 87.5% and 100%, respectively, in studies that used suitable "true positive" and "true negative" patient comparison groups and were considered to be of high scientific quality. Diagnostic DSe and DSp of RBT compared to culture in studies that also used suitable "true positive" and "true negative" patient comparison groups but were considered to be of moderate scientific quality varied from 92.5% to 100% and 94.3 to 99.9%, respectively. The good diagnostic performance of RBT combined with its simplicity, quickness, and affordability makes RBT an ideal (or close to) stand-alone point-of-care test for early clinical diagnosis and management of human brucellosis and nonmalarial fevers in small and understaffed health facilities and laboratories in endemic areas in Africa and elsewhere.

Fruit bats in flight: a look into the movements of the ecologically important Eidolon helvum in Tanzania.

BACKGROUND: Many ecologically important plants are pollinated or have their seeds dispersed by fruit bats, including the widely distributed African straw-colored fruit bats (Eidolon helvum). Their ability to fly long distances makes them essential for connecting plant populations across fragmented landscapes. While bats have been implicated as a reservoir of infectious diseases, their role in disease transmission to humans is not well understood. In this pilot study, we tracked E. helvum to shed light on their movement patterns in Tanzania and possible contact with other species. METHODS: Tracking devices were deployed on 25 bats captured in the Morogoro Municipal and Kilombero District area near the Udzungwa Mountains of Tanzania. Nightly flight patterns, areas corresponding to foraging bouts and feeding roosts, and new day roosts were determined from bat movement data and characterized according to their proximity to urban built-up and protected areas. Sites for additional environmental surveillance using camera traps were identified via tracking data to determine species coming in contact with fruits discarded by bats. RESULTS: Tracking data revealed variability between individual bat movements and a fidelity to foraging areas. Bats were tracked from one to six nights, with a mean cumulative nightly flight distance of 26.14 km (min: 0.33, max: 97.57) based on data from high-resolution GPS tags. While the majority of their foraging locations were in or near urban areas, bats also foraged in protected areas, of which the Udzungwa Mountains National Park was the most frequented. Camera traps in fruit orchards frequented by tracked bats showed the presence of multiple species of wildlife, with vervet monkeys (Chlorocebus pygerythrus) observed as directly handling and eating fruit discarded by bats. CONCLUSIONS: Because we observed multiple interactions of animals with fruits discarded by bats, specifically with vervet monkeys, the possibility of disease spillover risk exists via this indirect pathway. With flight distances of up to 97 km, however, the role of E. helvum in the seed dispersal of plants across both protected and urban built-up areas in Tanzania may be even more important, especially by helping connect increasingly fragmented landscapes during this Anthropocene epoch.

Spatial epidemiological patterns suggest mechanisms of land-sea transmission for Sarcocystis neurona in a coastal marine mammal.

Sarcocystis neurona was recognised as an important cause of mortality in southern sea otters (Enhydra lutris nereis) after an outbreak in April 2004 and has since been detected in many marine mammal species in the Northeast Pacific Ocean. Risk of S. neurona exposure in sea otters is associated with consumption of clams and soft-sediment prey and is temporally associated with runoff events. We examined the spatial distribution of S. neurona exposure risk based on serum antibody testing and assessed risk factors for exposure in animals from California, Washington, British Columbia and Alaska. Significant spatial clustering of seropositive animals was observed in California and Washington, compared with British Columbia and Alaska. Adult males were at greatest risk for exposure to S. neurona, and there were strong associations with terrestrial features (wetlands, cropland, high human housing-unit density). In California, habitats containing soft sediment exhibited greater risk than hard substrate or kelp beds. Consuming a diet rich in clams was also associated with increased exposure risk. These findings suggest a transmission pathway analogous to that described for Toxoplasma gondii, with infectious stages traveling in freshwater runoff and being concentrated in particular locations by marine habitat features, ocean physical processes, and invertebrate bioconcentration.

Giardia Infection and Trypanosoma Cruzi Exposure in Dogs in the Bosawás Biosphere Reserve, Nicaragua.

Indigenous Mayangna and Miskitu inhabit Nicaragua's remote Bosawás Biosphere Reserve, located in the North Caribbean Coast Autonomous Region. They are sedentary horticulturists who supplement their diet with wild game, hunting with the assistance of dogs. To test whether hunting dogs increased the risk of human exposure to protozoal zoonotic neglected tropical diseases (NTDs), we sampled dogs from three communities varying in population size and level of contact with other communities. We screened dog feces (n = 58) for Giardia and Cryptosporidium DNA and sera (n = 78) for Trypanosoma cruzi antibodies and DNA. Giardia DNA was detected in 22% (13/58) of samples; sequencing revealed the presence of both zoonotic genotypes (assemblages A and B) and dog-specific genotypes (assemblages C and D). Giardia shedding was associated with community and age. Older dogs and those in the two, more accessible communities had greater odds of shedding parasites. Seroprevalence of T. cruzi antibodies, indicating prior exposure, was 9% (7/78). These results contribute to the limited literature on NTDs in indigenous populations, and suggest hunting dogs can both serve as sentinels of environmental NTDs and pose zoonotic risk for their owners and communities.

OUTCOMES OF SNARE-RELATED INJURIES TO ENDANGERED MOUNTAIN GORILLAS ( GORILLA BERINGEI BERINGEI) IN RWANDA.

Mountain gorillas ( Gorilla beringei beringei) are one of the most critically endangered great apes in the world. The most common cause of mountain gorilla morbidity and mortality is trauma (e.g., injury from conspecifics or snare entrapment). We conducted a retrospective case-control study of free-ranging, human-habituated mountain gorillas to evaluate factors associated with snare entrapment and the results of clinical intervention. Data were collected from clinical records on all clinical intervention cases ( n=132) in Volcanoes National Park, Rwanda, conducted between 1995-2015. Wildlife veterinarians treated 37 gorillas entrapped in snares and 95 gorillas for other clinical conditions (including trauma and respiratory illness). Multivariate statistical analyses revealed that young gorillas (<8 yr old) were more likely than older gorillas to become snared; that comorbidities delayed times to intervention (≥3 d); and that severity of wounds at the time of intervention were associated with increased risk of lasting impairment (including loss of limb or limb function, or death) within 1 mo after intervention. Our results may influence decisions for gorilla health monitoring and treatment to most effectively conserve this critically endangered species.

Fecal indicator bacteria and zoonotic pathogens in marine snow and California mussels (Mytilus californianus).

Pollution of nearshore waters with disease-causing microorganisms impacts ecosystems health through illness and deaths in people and wildlife, as well as negative socioeconomic consequences of impaired marine resources. Insight on pathogen ecology in coastal habitats is crucial for accurately mitigating inputs and impacts of microbial pollution. Three objectives were addressed to (i) compare fecal pollution in proximity to (a) freshwater runoff, and (b) endemic marine wildlife; (ii) evaluate presence and magnitude of fecal microorganisms in marine snow and mussels and (iii) determine if pathogens in mussels and FIB levels in seawater or mussels are correlated. Sampling during the wet season, proximity to freshwater, and FIB levels in mussel homogenates (but not seawater) were associated with pathogen presence in mussels. Pathogens and FIB were enriched in aggregate-rich fractions, further supporting an important role of marine snow in pathogen transmission. The lack of association between FIB in surrounding waters and presence of pathogens in mussels calls into question current regulations for insuring safe seafood to consumers in the United States, and alternative monitoring approaches such as direct testing for select pathogens should be further evaluated.

Drinking Water Safety: Role of Hand Hygiene, Sanitation Facility, and Water System in Semi-Urban Areas of India.

Poor drinking water quality is one of the main causes of acute diarrheal disease in developing countries. The study investigated the relationship between fecal contamination of hands, stored drinking water, and source waters in India. We further evaluated the environmental and behavioral factors associated with recontamination of water between collection and consumption. The bacterial contamination, that is, Escherichia coli (log10 most probable number per two hands), found on mothers' hands (mean = 1.11, standard deviation [SD] = 1.2, N = 152) was substantially higher than that on their children younger than 5 years (mean = 0.64, SD = 1.0, and N = 152). We found a low level of E. coli (< 1 per 100 mL) in the source water samples; however, E. coli contamination in stored drinking water was above the recommended guidelines of the World Health Organization. The study also found that E. coli on hands was significantly associated with E. coli in the stored drinking water (P < 0.001). Moreover, E. coli was positively associated with gastrointestinal symptoms (odds ratio 1.42, P < 0.05). In the households with elevated levels (> 100 E. coli/100 mL) of fecal contamination, we found that 43.5% had unimproved sanitation facilities, poor water handling practices, and higher diarrheal incidences. The water quality deterioration from the source to the point of consumption is significant. This necessitates effective interventions in collection, transport, storage, and extraction practices when hand-water contact is likely to occur. These findings support the role of hands in the contamination of stored drinking water and suggest that clean source water does not guarantee safe water at the point of consumption.

Quantitative microbial risk assessment to estimate the risk of diarrheal diseases from fresh produce consumption in India.

This study estimates illness (diarrhea) risks from fecal pathogens that can be transmitted via fecal-contaminated fresh produce. To do this, a quantitative microbial risk assessment (QMRA) framework was developed in National Capital Region, India based on bacterial indicator and pathogen data from fresh produce wash samples collected at local markets. Produce wash samples were analyzed for fecal indicator bacteria (Escherichia coli, total Bacteroidales) and pathogens (Salmonella, Shiga-toxin producing E. coli (STEC), enterohemorrhagic E. coli (EHEC)). Based on the E. coli data and on literature values for Cryptosporidium and norovirus, the annual mean diarrhea risk posed by ingestion of fresh produce ranged from 18% in cucumbers to 59% in cilantro for E. coli O157:H7, and was <0.0001% for Cryptosporidium; for norovirus the risk was 11% for cucumbers and up to 46% for cilantro. The risks were drastically reduced, from 59% to 4% for E. coli O157:H7, and from 46% to 2% for norovirus for cilantro in post-harvest washing and disinfection scenario. The present QMRA study revealed the potential hazards of eating raw produce and how post-harvest practices can reduce the risk of illness. The results may lead to better food safety surveillance systems and use of hygienic practices pre- and post-harvest.

Estimating Cryptosporidium and Giardia disease burdens for children drinking untreated groundwater in a rural population in India.

BACKGROUND: In many low-income settings, despite improvements in sanitation and hygiene, groundwater sources used for drinking may be contaminated with enteric pathogens such as Cryptosporidium and Giardia, which remain important causes of childhood morbidity. In this study, we examined the contribution of diarrhea caused by Cryptosporidium and Giardia found in groundwater sources used for drinking to the total burden of diarrheal disease among children < 5 in rural India. METHODOLOGY/PRINCIPAL FINDINGS: We studied a population of 3,385 children < 5 years of age in 100 communities of Puri District, Odisha, India. We developed a coupled quantitative microbial risk assessment (QMRA) and susceptible-infected-recovered (SIR) population model based on observed levels of Cryptosporidium and Giardia in improved groundwater sources used for drinking and compared the QMRA-SIR estimates with independently measured all-cause (i.e., all fecal-oral enteric pathogens and exposure pathways) child diarrhea prevalence rates observed in the study population during two monsoon seasons (2012 and 2013). We used site specific and regional studies to inform assumptions about the human pathogenicity of the Cryptosporidium and Giardia species present in local groundwater. In all three human pathogenicity scenarios evaluated, the mean daily risk of Cryptosporidium or Giardia infection (0.06-1.53%), far exceeded the tolerable daily risk of infection from drinking water in the US (< 0.0001%). Depending on which protozoa species were present, median estimates of daily child diarrhea prevalence due to either Cryptosporidium or Giardia infection from drinking water was as high as 6.5% or as low as < 1% and accounted for at least 2.9% and as much as 65.8% of the all-cause diarrhea disease burden measured in children < 5 during the study period. Cryptosporidium tended to account for a greater share of estimated waterborne protozoa infections causing diarrhea than did Giardia. Diarrhea prevalence estimates for waterborne Cryptosporidium infection appeared to be most sensitive to assumptions about the probability of infection from ingesting a single parasite (i.e. the rate parameter in dose-response model), while Giardia infection was most sensitive to assumptions about the viability of parasites detected in groundwater samples. CONCLUSIONS/SIGNIFICANCE: Protozoa in groundwater drinking sources in rural India, even at low concentrations, especially for Cryptosporidium, may account for a significant portion of child diarrhea morbidity in settings were tubewells are used for drinking water and should be more systematically monitored. Preventing diarrheal disease burdens in Puri District and similar settings will benefit from ensuring water is microbiologically safe for consumption and consistent and effective household water treatment is practiced.

A community-based One Health education program for disease risk mitigation at the human-animal interface.

The interface between humans, domestic animals, and wildlife has been implicated in the emergence of infectious diseases and the persistence of endemic human and animal diseases. For individuals who reside at this interface, particularly those in low-resource settings, the development of disease risk assessment and mitigation skills must be prioritized. Using a community engagement-One Health approach, we implemented a training program aimed at advancing these skills among agro-pastoralists living adjacent to conservation areas in South Africa. The program included professional development of local facilitators who then conducted workshops with community members. Workshops used a series of experiential, inquiry-based activities to teach participants the concepts of pathogen transmission and disease risk assessment and mitigation. The program was implemented over four weeks with 10 facilitators and 78 workshop participants. We conducted a within-subjects experimental study using a mixed methods design to evaluate the program in terms of facilitator and participant One Health knowledge and practices. Quantitative data included pre/post written assessments; qualitative data included focus group discussions, semi-structured interviews, and pre/post photographs. Mean post-test scores of facilitators increased by 17% (p = 0.0078). For workshop participants, improvements in knowledge were more likely for females than males (OR = 7.315, 95% CI = 2.258-23.705, p = 0.0009) and participants with a higher versus lower education level, albeit borderline non-significant (OR = 4.781, 95% CI = 0.942-24.264, p = 0.0590). Qualitative analysis revealed the implementation of risk mitigation strategies by 98% (60/61) of workshop participants during the three-month follow-up and included improved personal and domestic hygiene practices and enhanced animal housing. Although further evaluation is recommended, this program may be appropriate for consideration as a scalable approach by which to mitigate human and animal infectious disease risk in high-risk/low-resource communities.

Daily relative dog abundance, fecal density, and loading rates on intensively and minimally managed dog-friendly beaches in central California.

Due to increased concerns regarding fecal pollution at marine recreational beaches, daily relative dog abundance and fecal density were estimated on an intensively managed (Beach 1) and a minimally managed (Beach 2) dog beach in Monterey County, California. Fecal loading and factors predictive of fecal deposition also were assessed. After standardizing for beach area, daily beach use and fecal densities did not differ between beaches and yearly fecal loading estimates revealed that unrecovered dog feces likely contributes significantly to fecal contamination (1.4 and 0.2metrictonnes/beach). Detection of feces was significantly associated with beach management type, transect position relative to mean low tideline, presence of beach wrack, distance to the nearest beach entrance, and season. Methodologies outlined in this study can augment monitoring programs at coastal beaches to optimize management, assess visitor compliance, and improve coastal water quality.