scholarly journals Inactivation of Cryptosporidium parvum under chlorinated recreational water conditions

2008 ◽  
Vol 6 (4) ◽  
pp. 513-520 ◽  
Author(s):  
Joan M. Shields ◽  
Vincent R. Hill ◽  
Michael J. Arrowood ◽  
Michael J. Beach
Keyword(s):  
Public Health ◽  
Tissue Culture ◽  
Sodium Hypochlorite ◽  
Cryptosporidium Parvum ◽  
Protozoan Parasite ◽  
Recreational Water ◽  
Log Reduction ◽  
Cryptosporidium Oocysts ◽  
Water Conditions ◽  
Control And Prevention

Cryptosporidium is a chlorine-resistant protozoan parasite and the etiological agent in many disinfected recreational water outbreaks. While previous studies have reported disinfection Ct values for Cryptosporidium parvum using sodium hypochlorite, these studies have employed conditions and procedures which are not ideal for establishing public health remediation recommendations for chlorinated recreational water venues. In the present study, free chlorine Ct values were measured at pH 7.5 using young oocysts (<1 month old) and tissue culture to determine oocyst viability. Two different oocyst isolates were used: one originating from Iowa and one from Maine (USA). This study determined that the Ct values for a 3-log reduction in oocyst viability were 10,400 (Iowa) and 15,300 (Maine) at pH 7.5. These Ct values are higher than the Centers for Disease Control and Prevention (USA) currently recommends (Ct=9,600) for achieving a 3.0-log inactivation of Cryptosporidium oocysts during remediation of recreational water venues following fecal diarrhea accidents.

scholarly journals The effect of cyanuric acid on the disinfection rate of Cryptosporidium parvum in 20-ppm free chlorine

2008 ◽  
Vol 7 (1) ◽  
pp. 109-114 ◽  
Author(s):  
Joan M. Shields ◽  
Michael J. Arrowood ◽  
Vincent R. Hill ◽  
Michael J. Beach
Keyword(s):  
Public Health ◽  
Cryptosporidium Parvum ◽  
Cyanuric Acid ◽  
Free Chlorine ◽  
Swimming Pool ◽  
Swimming Pools ◽  
Log10 Reduction ◽  
Chlorine Residual ◽  
Cryptosporidium Oocysts ◽  
Reduction Current

Cyanuric acid is used to stabilize free chlorine to reduce photodegradation in outdoor swimming pools. While there have been numerous studies examining its effect on the disinfection rates of bacteria and viruses, it is not known whether cyanuric acid can significantly impact the effectiveness of hyperchlorination for inactivating Cryptosporidium oocysts present in fecally-contaminated swimming pools. This study examined the effect of cyanuric acid on the disinfection rate of Cryptosporidium parvum under swimming pool hyperchlorination conditions (20 mg/ml free chlorine). When 50 mg/L cyanuric acid was present there was a 0.70-log10 reduction in oocyst viability after 10 hours as compared to a 3.7-log10 reduction without cyanuric acid. Aids to remediation, such as decreasing the pH to enhance the germicidal efficiency of the free chlorine and doubling the amount of free chlorine residual, were still unable to achieve a 3-log10 reduction. Current public health recommendations for hyperchlorination and pool remediation are insufficient for pools using cyanurate-stabilized chlorine to achieve a three log inactivation of the parasite.

scholarly journals Disposable swim diaper retention of Cryptosporidium-sized particles on human subjects in a recreational water setting

2011 ◽  
Vol 9 (4) ◽  
pp. 653-658 ◽  
Author(s):  
James E. Amburgey ◽  
J. Brian Anderson
Keyword(s):  
Human Subject ◽  
Human Subjects ◽  
Disease Outbreaks ◽  
Protozoan Parasite ◽  
Bulk Water ◽  
Recreational Water ◽  
Swimming Pools ◽  
Polystyrene Microspheres ◽  
Cryptosporidium Oocysts ◽  
The Usa

Cryptosporidium is a chlorine-resistant protozoan parasite responsible for the majority of waterborne disease outbreaks in recreational water venues in the USA. Swim diapers are commonly used by diaper-aged children participating in aquatic activities. This research was intended to evaluate disposable swim diapers for retaining 5-μm diameter polystyrene microspheres, which were used as non-infectious surrogates for Cryptosporidium oocysts. A hot tub recirculating water without a filter was used for this research. The microsphere concentration in the water was monitored at regular intervals following introduction of microspheres inside of a swim diaper while a human subject undertook normal swim/play activities. Microsphere concentrations in the bulk water showed that the majority (50–97%) of Cryptosporidium-sized particles were released from the swim diaper within 1 to 5 min regardless of the swim diaper type or configuration. After only 10 min of play, 77–100% of the microspheres had been released from all swim diapers tested. This research suggests that the swim diapers commonly used by diaper-aged children in swimming pools and other aquatic activities are of limited value in retaining Cryptosporidium-sized particles. Improved swim diaper solutions are necessary to efficiently retain pathogens and effectively safeguard public health in recreational water venues.

Communications and Politics

2018 ◽  
Author(s):  
Joshua M. Sharfstein
Keyword(s):  
Public Health ◽  
Disease Control ◽  
Accurate Information ◽  
Political Judgment ◽  
Political Leaders ◽  
Health Crisis ◽  
Public Health Crisis ◽  
Control And Prevention ◽  
Public Health Officials ◽  
Centers For Disease Control

An effective communications approach starts with a basic dictum set forth by the Centers for Disease Control and Prevention: “Be first, be right, be credible.” Agencies must establish themselves as vital sources of accurate information to maintain the public’s trust. At the same time, public health officials must recognize that communications play out in the context of ideological debates, electoral rivalries, and other political considerations. During a public health crisis, this means that health officials often need to constructively engage political leaders in communications and management. Navigating these waters in the middle of a crisis can be treacherous. Figuring out the best way to engage elected leaders is a core aspect of political judgment.

scholarly journals Users’ Beliefs Toward Physical Distancing in Facebook Pages of Public Health Authorities During COVID-19 Pandemic in Early 2020

2021 ◽  
pp. 109019812110144
Author(s):  
Soon Guan Tan ◽  
Aravind Sesagiri Raamkumar ◽  
Hwee Lin Wee
Keyword(s):  
Public Health ◽  
Health Belief Model ◽  
United States Public Health ◽  
Health Belief ◽  
The United States ◽  
Health Authorities ◽  
Public Health Authorities ◽  
Control And Prevention ◽  
Belief Model ◽  
The Health Belief Model

This study aims to describe Facebook users’ beliefs toward physical distancing measures implemented during the Coronavirus disease (COVID-19) pandemic using the key constructs of the health belief model. A combination of rule-based filtering and manual classification methods was used to classify user comments on COVID-19 Facebook posts of three public health authorities: Centers for Disease Control and Prevention of the United States, Public Health England, and Ministry of Health, Singapore. A total of 104,304 comments were analyzed for posts published between 1 January, 2020, and 31 March, 2020, along with COVID-19 cases and deaths count data from the three countries. Findings indicate that the perceived benefits of physical distancing measures ( n = 3,463; 3.3%) was three times higher than perceived barriers ( n = 1,062; 1.0%). Perceived susceptibility to COVID-19 ( n = 2,934; 2.8%) was higher compared with perceived severity ( n = 2,081; 2.0%). Although susceptibility aspects of physical distancing were discussed more often at the start of the year, mentions on the benefits of intervention emerged stronger toward the end of the analysis period, highlighting the shift in beliefs. The health belief model is useful for understanding Facebook users’ beliefs at a basic level, and it provides a scope for further improvement.

scholarly journals High Diversity of Cryptosporidium Species and Subtypes Identified in Cryptosporidiosis Acquired in Sweden and Abroad

Pathogens ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 523
Author(s):  
Marianne Lebbad ◽  
Jadwiga Winiecka-Krusnell ◽  
Christen Rune Stensvold ◽  
Jessica Beser
Keyword(s):  
Cryptosporidium Parvum ◽  
Ribosomal Rna ◽  
Diarrheal Disease ◽  
Protozoan Parasite ◽  
Small Subunit ◽  
Cryptosporidium Species ◽  
Intestinal Protozoan ◽  
Genotype I ◽  
Glycoprotein Gene ◽  
High Diversity

The intestinal protozoan parasite Cryptosporidium is an important cause of diarrheal disease worldwide. The aim of this study was to expand the knowledge on the molecular epidemiology of human cryptosporidiosis in Sweden to better understand transmission patterns and potential zoonotic sources. Cryptosporidium-positive fecal samples were collected between January 2013 and December 2014 from 12 regional clinical microbiology laboratories in Sweden. Species and subtype determination was achieved using small subunit ribosomal RNA and 60 kDa glycoprotein gene analysis. Samples were available for 398 patients, of whom 250 (63%) and 138 (35%) had acquired the infection in Sweden and abroad, respectively. Species identification was successful for 95% (379/398) of the samples, revealing 12 species/genotypes: Cryptosporidium parvum (n = 299), C. hominis (n = 49), C. meleagridis (n = 8), C. cuniculus (n = 5), Cryptosporidium chipmunk genotype I (n = 5), C. felis (n = 4), C. erinacei (n = 2), C. ubiquitum (n = 2), and one each of C. suis, C. viatorum, C. ditrichi, and Cryptosporidium horse genotype. One patient was co-infected with C. parvum and C. hominis. Subtyping was successful for all species/genotypes, except for C. ditrichi, and revealed large diversity, with 29 subtype families (including 4 novel ones: C. parvum IIr, IIs, IIt, and Cryptosporidium horse genotype VIc) and 81 different subtypes. The most common subtype families were IIa (n = 164) and IId (n = 118) for C. parvum and Ib (n = 26) and Ia (n = 12) for C. hominis. Infections caused by the zoonotic C. parvum subtype families IIa and IId dominated both in patients infected in Sweden and abroad, while most C. hominis cases were travel-related. Infections caused by non-hominis and non-parvum species were quite common (8%) and equally represented in cases infected in Sweden and abroad.

scholarly journals Interrupted time series design to evaluate ICD-9-CM to ICD-10-CM coding changes on trends in Colorado emergency department visits related to traumatic brain injury

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Lauren Alexis De Crescenzo ◽  
Barbara Alison Gabella ◽  
Jewell Johnson
Keyword(s):  
Public Health ◽  
Traumatic Brain Injury ◽  
Emergency Department ◽  
Brain Injury ◽  
Interrupted Time Series ◽  
Emergency Department Visits ◽  
Control And Prevention ◽  
Icd 10 ◽  
Ed Visits ◽  
The Impact

Abstract Background The transition in 2015 to the Tenth Revision of the International Classification of Disease, Clinical Modification (ICD-10-CM) in the US led the Centers for Disease Control and Prevention (CDC) to propose a surveillance definition of traumatic brain injury (TBI) utilizing ICD-10-CM codes. The CDC’s proposed surveillance definition excludes “unspecified injury of the head,” previously included in the ICD-9-CM TBI surveillance definition. The study purpose was to evaluate the impact of the TBI surveillance definition change on monthly rates of TBI-related emergency department (ED) visits in Colorado from 2012 to 2017. Results The monthly rate of TBI-related ED visits was 55.6 visits per 100,000 persons in January 2012. This rate in the transition month to ICD-10-CM (October 2015) decreased by 41 visits per 100,000 persons (p-value < 0.0001), compared to September 2015, and remained low through December 2017, due to the exclusion of “unspecified injury of head” (ICD-10-CM code S09.90) in the proposed TBI definition. The average increase in the rate was 0.33 visits per month (p < 0.01) prior to October 2015, and 0.04 visits after. When S09.90 was included in the model, the monthly TBI rate in Colorado remained smooth from ICD-9-CM to ICD-10-CM and the transition was no longer significant (p = 0.97). Conclusion The reduction in the monthly TBI-related ED visit rate resulted from the CDC TBI surveillance definition excluding unspecified head injury, not necessarily the coding transition itself. Public health practitioners should be aware that the definition change could lead to a drastic reduction in the magnitude and trend of TBI-related ED visits, which could affect decisions regarding the allocation of TBI resources. This study highlights a challenge in creating a standardized set of TBI ICD-10-CM codes for public health surveillance that provides comparable yet clinically relevant estimates that span the ICD transition.

scholarly journals Tracking U.S. Pertussis Incidence: Correlation of Public Health Surveillance and Google Search Data Varies by State

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Christopher H. Arehart ◽  
Michael Z. David ◽  
Vanja Dukic
Keyword(s):  
Public Health ◽  
Linear Models ◽  
State Level ◽  
Individual State ◽  
Control And Prevention ◽  
Search Data ◽  
State Models ◽  
Uniform Manner ◽  
Google Search ◽  
The U.S

AbstractThe Morbidity and Mortality Weekly Reports of the U.S. Centers for Disease Control and Prevention document a raw proxy for counts of pertussis cases in the U.S., and the Project Tycho (PT) database provides an improved source of these weekly data. These data are limited because of reporting delays, variation in state-level surveillance practices, and changes over time in diagnosis methods. We aim to assess whether Google Trends (GT) search data track pertussis incidence relative to PT data and if sociodemographic characteristics explain some variation in the accuracy of state-level models. GT and PT data were used to construct auto-correlation corrected linear models for pertussis incidence in 2004–2011 for the entire U.S. and each individual state. The national model resulted in a moderate correlation (adjusted R2 = 0.2369, p < 0.05), and state models tracked PT data for some but not all states. Sociodemographic variables explained approximately 30% of the variation in performance of individual state-level models. The significant correlation between GT models and public health data suggests that GT is a potentially useful pertussis surveillance tool. However, the variable accuracy of this tool by state suggests GT surveillance cannot be applied in a uniform manner across geographic sub-regions.

scholarly journals Regulations concerning natural swimming ponds in Europe: considerations on public health issues

2014 ◽  
Vol 12 (3) ◽  
pp. 564-572 ◽  
Author(s):  
Saverio Giampaoli ◽  
Nathalie Garrec ◽  
Gérard Donzé ◽  
Federica Valeriani ◽  
Lothar Erdinger ◽  
...  
Keyword(s):  
Public Health ◽  
Water Management ◽  
Scientific Community ◽  
National Policy ◽  
Microbiological Analysis ◽  
Recreational Water ◽  
Health Issues ◽  
Local Authorities ◽  
European Directive ◽  
New Type

Natural swimming ponds (NSPs) are a new type of recreational water facility characterized by the substitution of traditional disinfection with biodepuration. While this feature meets esthetic desires of users, specific concerns on public health issues have been raised by the scientific community and local authorities. The absence of a European directive applicable to these environments leaves each country without specific and harmonized indications. The present work describes the local/national policy situation, describing adopted parameters and monitoring activities. All documents underline the need for appropriate microbiological analysis and correct water management.

scholarly journals Sources and Species of Cryptosporidium Oocysts in the Wachusett Reservoir Watershed

2002 ◽  
Vol 68 (2) ◽  
pp. 569-575 ◽  
Author(s):  
Kristen L. Jellison ◽  
Harold F. Hemond ◽  
David B. Schauer
Keyword(s):  
Public Health ◽  
Surface Waters ◽  
Management Practices ◽  
Immunofluorescence Microscopy ◽  
Cold Water ◽  
Environmental Data ◽  
The Public ◽  
Specificity And Sensitivity ◽  
Cryptosporidium Oocysts ◽  
Reservoir Watershed

ABSTRACT Understanding the behavior of Cryptosporidium oocysts in the environment is critical to developing improved watershed management practices for protection of the public from waterborne cryptosporidiosis. Analytical methods of improved specificity and sensitivity are essential to this task. We developed a nested PCR-restriction fragment length polymorphism assay that allows detection of a single oocyst in environmental samples and differentiates the human pathogen Cryptosporidium parvum from other Cryptosporidium species. We tested our method on surface water and animal fecal samples from the Wachusett Reservoir watershed in central Massachusetts. We also directly compared results from our method with those from the immunofluorescence microscopy assay recommended in the Information Collection Rule. Our results suggest that immunofluorescence microscopy may not be a reliable indicator of public health risk for waterborne cryptosporidiosis. Molecular and environmental data identify both wildlife and dairy farms as sources of oocysts in the watershed, implicate times of cold water temperatures as high-risk periods for oocyst contamination of surface waters, and suggest that not all oocysts in the environment pose a threat to public health.

scholarly journals Cryptosporidium infection in non-human hosts in Malawi

2009 ◽  
Vol 76 (4) ◽  
Author(s):  
Z. Banda ◽  
Rosely A.B. Nichols ◽  
A.M. Grimason ◽  
H.V. Smith
Keyword(s):  
Cryptosporidium Parvum ◽  
Rainy Season ◽  
18S Rrna ◽  
Cryptosporidium Oocyst ◽  
Dry Season ◽  
Cool Season ◽  
Cryptosporidium Hominis ◽  
Adult Cattle ◽  
Faecal Samples ◽  
Cryptosporidium Oocysts

Of 1 346 faecal samples from the Chikwawa and Thyolo districts of Malawi, analysed for the presence of Cryptosporidium oocysts between October 2001 and May 2003, 61.3 % were from cattle (29.8 % of these were from calves < 6 months old). Cryptosporidium oocysts were detected during all three seasons studied in Chikwawa and Thyolo. In Chikwawa, 13.6 % of adult cattle and 11.7 % of calves were infected, compared to 28.9 % of adult cattle and 36.7 % of calves in Thyolo. Dependent on season, between 7.8 % and 37.7 % (Chikwawa) and 16.7 % and 39.3 % (Thyolo) of cattle samples contained oocysts. In Chikwawa, the highest percentage of infections occurred in the cool season, whereas in Thyolo, the highest percentage of infections occurred in the dry season. Faecal samples from goats [n = 225], pigs [n = 92], sheep [n = 6]), rabbits, guinea pigs, chickens, ducks, turkeys, doves and guinea fowls were also analysed. Up to 5.6 % of goat samples contained oocysts in Chikwawa, compared to between 16.7 % and 39.3 % in Thyolo. Again, in Chikwawa, the highest percentage of infections occurred in the cool season and the lowest in the rainy season, whereas, in Thyolo, the highest percentage of infections occurred in the dry season and the lowest in the cool season. In pigs, more infections were detected in the dry season in Chikwawa, but infections in the cool season were similar (17.7 %), whereas in Thyolo, infections occurred in all three seasons (17.9 % in the rainy season, 25 % in the cool season and 60 % in the dry season). Often diarrhoeic, oocyst positive cattle faecal samples collected from Chikwawa and subjected to PCR-RFLP, four oocyst positive samples (two from heifers, one from a cow and one unknown) were amplified at an 18S rRNA and Cryptosporidium oocyst wall protein (COWP) loci. RFLP of the 18S rRNA locus indicated that Cryptosporidium parvum, Cryptosporidium hominis, Cryptosporidium bovis and / or Cryptosporidium ryanae DNA, or a mixture of them was present. Cryptosporidium parvum DNA was identified in one sample that amplified at the COWP locus, indicating the presence of the major zoonotic Cryptosporidium species in Malawi.

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