Better ways to monitor beaver fever

The current approach in the U.S. water industry for monitoring Cryptosporidium and Giardia has weaknesses that have contributed to the difficulty of interpreting resulting data. This often leads to potentially significant and dangerous misinterpretation. The purpose of this paper is to summarize information on which the conflicting conclusions on the occurrence and distribution of Cryptosporidium and Giardia have been based.

giardia_lambliaEffort is made to determine the most plausible and supportable interpretation. The objective is to provide a basis for rethinking the current approach to monitoring and management of Cryptosporidium and Giardia in water.

The importance of measuring recovery efficiency and reporting measurements of these organisms in terms of concentration to any quantitative application is emphasized. Data presentation to illustrate critical features of organism concentration levels and variation is reviewed. Analysis of major data sets resulting from the U.S. Environmental Protection Agency Information Collection Rule Supplemental Survey (USEPA ICR SS) and the Long-Term 2 Enhanced Surface Water Treatment Rule (LT2) monitoring and other previously published relevant data sets is presented to illustrate key features of Cryptosporidium and Giardia occurrence in surface water and their universal geographic distribution. Current thinking emphatically requires revision.

Cryptosporidium and Giardia in water: reassessment of occurrence and significance

ASCE

Jerry E.Ongerth

http://ascelibrary.org/doi/abs/10.1061/(ASCE)EE.1943-7870.0001161

Giardia — beaver fever – can be serious

Although most individuals with a Giardia infection are asymptomatic, this pathogen is increasingly recognized as a cause of pathologies beyond the classical manifestations.

beaver.feverMorbidities associated with Giardia, including extra-intestinal manifestations and long-term consequences, have been identified increasingly over the past decades. The importance of this pathogen in terms of patient well-being and its effect on quality of life, due to being a continuing cause of patient discomfort and pain, has been highlighted .

Sequelae of giardiasis: an emerging public health concern

Angel A. Escobedo, Pedro Almirall, Sérgio Cimerman, Alfonso J. Rodríguez-Morales

International Journal of Infectious Diseases, August 2016, Volume 49, Pages 202-203, DOI: http://dx.doi.org/10.1016/j.ijid.2016.06.008

http://www.ijidonline.com/article/S1201-9712(16)31092-X/abstract

Beaver fever: Petting zoos, untreated water primary sources of Giardia at home and abroad

The purpose of this study is to determine how demographic and exposure factors related to giardiasis vary between travel and endemic cases.

beaver.feverExposure and demographic data were gathered by public health inspectors from giardiasis cases reported from the Region of Waterloo from 2006 to 2012. Logistic regression models were fit to assess differences in exposure to risk factors for giardiasis between international travel-related cases and Canadian acquired cases while controlling for age and sex. Multinomial regression models were also fit to assess the differences in risk profiles between international and domestic travel-related cases and endemic cases.

Travel-related cases (both international and domestic) were more likely to go camping or kayaking, and consume untreated water compared to endemic cases. Domestic travel-related cases were more likely to visit a petting zoo or farm compared to endemic cases, and were more likely to swim in freshwater compared to endemic cases and international travel-related cases. International travellers were more likely to swim in an ocean compared to both domestic travel-related and endemic cases.

These findings demonstrate that travel-related and endemic cases have different risk exposure profiles which should be considered for appropriately targeting health promotion campaigns.

Beaver_FeverA comparison of exposure to risk factors for giardiasis in non-travellers, domestic travellers and international travellers in a Canadian community, 2006–2012

Epidemiology and Infection, Volume 144, Issue 5, April 2016, pages 980-999, DOI: http://dx.doi.org/10.1017/S0950268815002186

L. Swirski, D. L. Pearl, A. S. Peregrine, and K. Pintar

http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=10216090&utm_source=Issue_Alert&utm_medium=RSS&utm_campaign=HYG

Beaver fever in U.S., 1971–2011

My friend was at his cabin near Algonquin Park (that’s in Canada) and twittered that his wife wanted to know if it was OK to use stream water to boil potatoes.

french.dont.eat.poopHe said sure, as long as you don’t mind the beaver poop.

We’ve had a long tradition of don’t eat poop, but if you do, make sure it’s cooked.

Giardia intestinalis is the leading parasitic aetiology of human enteric infections in the United States, with an estimated 1·2 million cases occurring annually. To better understand transmission, we analysed data on all giardiasis outbreaks reported to the Centers for Disease Control and Prevention for 1971–2011.

The 242 outbreaks, affecting ~41 000 persons, resulted from waterborne (74·8%), foodborne (15·7%), person-to-person (2·5%), and animal contact (1·2%) transmission. Most (74·6%) waterborne outbreaks were associated with drinking water, followed by recreational water (18·2%). Problems with water treatment, untreated groundwater, and distribution systems were identified most often during drinking water-associated outbreak investigations; problems with water treatment declined after the 1980s. Most recreational water-associated outbreaks were linked to treated swimming venues, with pools and wading pools implicated most often. Produce was implicated most often in foodborne outbreaks. Additionally, foods were most commonly prepared in a restaurant and contaminated by a food handler.

giardia-posterLessons learned from examining patterns in outbreaks over time can help prevent future disease. Groundwater and distribution system vulnerabilities, inadequate pool disinfection, fruit and vegetable contamination, and poor food handler hygiene are promising targets for giardiasis prevention measures.

Giardiasis outbreaks in the United States, 1971–2011

11.jan.16

Epidemiology and Infection

DOI: http://dx.doi.org/10.1017/S0950268815003040

E.A. Adam, J.S. Yoder, L.H. Gould, M.C. Hlavsa, and W. Gargano

http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=10111419&fileId=S0950268815003040

 

Beaver fever: Giardiasis surveillance, US 2011–2012

Problem/Condition: Giardiasis is a nationally notifiable gastrointestinal illness caused by the protozoan parasite Giardia intestinalis.

Reporting Period: 2011–2012.

beaver.feverDescription of System: Forty-four states, the District of Columbia, New York City, the Commonwealth of Puerto Rico, and Guam voluntarily reported cases of giardiasis to CDC through the National Notifiable Diseases Surveillance System (NNDSS).

Results: For 2011, a total of 16,868 giardiasis cases (98.8% confirmed and 1.2% nonconfirmed) were reported; for 2012, a total of 15,223 cases (98.8% confirmed and 1.3% nonconfirmed) were reported. In 2011 and 2012, 1.5% and 1.3% of cases, respectively, were associated with a detected outbreak. The incidence rates of all reported cases were 6.4 per 100,000 population in 2011 and 5.8 per 100,000 population in 2012. This represents a slight decline from the relatively steady rates observed during 2005–2010 (range: 7.1–7.9 cases per 100,000 population). In both 2011 and 2012, cases were most frequently reported in children aged 1–4 years, followed by those aged 5–9 years and adults aged 45–49 years. Incidence of giardiasis was highest in Northwest states. Peak onset of illness occurred annually during early summer through early fall.

Interpretation: For the first time since 2002, giardiasis rates appear to be decreasing. Possible reasons for the decrease in rates during 2011–2012 could include changes in transmission patterns, a recent change in surveillance case definition, increased uptake of strategies to reduce waterborne transmission, or a combination of these factors. Transmission of giardiasis occurs throughout the United States, with more frequent diagnosis or reporting occurring in northern states. Geographical differences might suggest actual regional differences in giardiasis transmission or variation in surveillance capacity across states. Six states did not report giardiasis cases in 2011–2012, representing the largest number of nonreporting states since giardiasis became nationally notifiable in 2002. Giardiasis is reported more frequently in young children, which might reflect increased contact with contaminated water or ill persons, or a lack of immunity.

Public Health Action: Educational efforts to decrease exposure to unsafe drinking and recreational water and prevent person-to-person transmission have the potential to reduce giardiasis transmission. The continual decrease in jurisdictions opting to report giardiasis cases could negatively impact the ability to interpret national surveillance data; thus, further investigation is needed to identify barriers to and facilitators of giardiasis case reporting. Existing state and local public health infrastructure supported through CDC (e.g., Epidemiology and Laboratory Capacity grants and CDC-sponsored Council of State and Territorial Epidemiologists Applied Epidemiology Fellows) could provide resources to enhance understanding of giardiasis epidemiology.

Beaver fever closes New York spring; 6 sick from giardia

The Times Union reports the Rensselaer County Health Department closed a spring Friday after six people became sick with "beaver fever” after drinking water obtained from the site.

Residents are advised not to drink water from a spring located one-quarter mile north of the intersection of routes 22 and 43.

The intestinal illness is caused by a microscopic parasite called Giardia lamblia.