E.coli, Giardia and crypto: Beware the duck pond at NZ Botanical Gardens

Gisborne’s chief medical officer has warned parents that children do not have to be in contact with water to pick up bugs from dirty water at the Botanical Gardens.

botanical-garden-japaneseGisborne District Council this week confirmed the duck pond at the gardens contained E.coli, Giardia and Cryptosporidium.

Although a statement from GDC said someone would have to drink “a good amount” of water to get sick, medical officer of health Dr Margot McLean pointed out that was not the case.

“You don’t have to enter the pond or drink the pond water to pick up the bugs that can make you sick. You could also pick up the bugs by putting hands in the water or touching areas where there is duck poo.

“This shouldn’t put people off visiting the ducks, as long as extra care is taken with hand hygiene.

“Antibacterial wipes could be used immediately after leaving the area, however parents should supervise children washing their hands and use the 20/20 rule; 20 seconds to wash/20 seconds to dry on the return home.

“Any duck poo should be removed from shoes so that the poo doesn’t contaminate surfaces like floors, or hands.”

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


Jerry E.Ongerth


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


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


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


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



Crypto and giardia take $5 billion bite out of NYC

Two tiny organisms present a big problem for New York City’s water department: cryptosporidium and giardia.

crypto.waterThe city has spent $5 billion over the last five years combatting these organisms, which can cause fatal illnesses in the sick and elderly and gastrointestinal problems for those with healthy immune systems.

“In the city’s east-of-Hudson Croton watershed, where development has encroached on watershed land, federal regulators forced the city to filter the water; hence the $3 billion Croton filtration plant that recently opened,” City Limits reported.

The plant itself was a giant, politically fraught project.

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.

It’s not just bacteria and viruses; parasites in leafy greens

On July 7, 1997, a company physician reported to the Alexandria Department of Health (ADOH) that most of the employees who attended a corporate luncheon on June 26 at the company’s branch in Fairfax, Virginia, had developed gastrointestinal illness. On July 11, the health department was notified that a stool specimen from one of the employees who attended the luncheon was positive for Cyclospora oocysts. Many others tested positive. It was subsequently revealed in a July 19, 1997, Washington Post story citing pesto_basil_cyclosporalocal health department officials that basil and pesto from four Sutton Place Gourmet stores around Washington D.C. was the source of cyclospora for 126 people who attended at least 19 separate events where Sutton Place basil products were served, from small dinner parties and baby showers to corporate gatherings. Of the 126, 30 members of the National Symphony Orchestra became sick after they ate box lunches provided by Sutton Place at Wolf Trap Farm Park.

In May 2001, 17 people in British Columbia were sickened with cyclospora associated with basil from Thailand. In 2005, 300 people in Florida were sickened with cyclospora from fresh basil.

My aunt was part of that outbreak.

Parasites. They’re everywhere.

Canadian researchers report in the Journal of Food Protection a “relatively high prevalence” of Cyclospora, Cryptosporidium and Giardia in ready-to-eat packaged leafy greens; most of the products were grown in the U.S.

Abstract below.

Detection of Cyclospora, Cryptosporidium, and Giardia in ready-to-eat packaged leafy greens in Ontario, Canada

Journal of Food Protection®, Number 2, February 2013, pp. 192-369 , pp. 307-313(7)

Dixon, Brent; Parrington, Lorna; Cook, Angela; Pollari, Frank; Farber, Jeffrey


Numerous foodborne outbreaks of diarrheal illness associated with the consumption of produce contaminated with protozoan parasites have been reported in North America in recent years. The present study reports on the presence of Cyclospora, Cryptosporidium, and Giardia in precut salads and lettuceleafy greens purchased at retail in Ontario, Canada. A total of 544 retail samples were collected between April 2009 and March 2010 and included a variety of salad blends and individual leafy greens. Most of these products were grown in the United States, with some from Canada and Mexico. Parasites were eluted and concentrated before detection by PCR and immunofluorescence microscopy. DNA sequences were aligned with reference sequences in GenBank. Cyclospora spp. were identified by PCR-restriction fragment length polymorphism in nine (1.7 % ) samples and by DNA sequence analysis. Cryptosporidium spp. were identified in 32 (5.9%) samples; 29 were sequenced and aligned with the zoonotic species Cryptosporidium parvum. Giardia duodenalis was identified in 10 (1.8%) samples, and of the 9 samples successfully sequenced, 7 aligned with G. duodenalis assemblage B and 2 with assemblage A, both of which are also zoonotic. The presence of Cryptosporidium oocysts and Giardia cysts was confirmed in some of the PCR-positive samples using microscopy, while Cyclospora -like oocysts were observed in most of the Cyclospora PCR-positive samples. The relatively high prevalence of these parasites in packaged salads and leafy greens establishes a baseline for further studies and suggests a need for additional research with respect to the possible sources of contamination of these foods, the determination of parasite viability and virulence, and means to reduce foodborne transmission to humans.

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.

Don’t kiss fish

I’ve written extensively about the salmonella-related dangers of kissing pet turtles during my time as an emotionally-vacant adolescent.

Martin Armstrong, a member of the Fisheries Advisory Council, a life member in Trout Unlimited and a member of the Outdoor Writers Association of America, asks in The Advocate, ever watch a competitive angler on TV kiss a big fish that he just caught?

Did you ever kiss a big fish that made your day or, better yet, win a party boat pool?

Well, when you kiss that big fish you are risking contracting a bothersome intestinal parasite.

Giardiasis is a diarrheal illness caused by a microscopic parasite, Giardia intestinalis (also known as Giardia lamblia or Giardia duodenalis). Once a person or animal has been infected with Giardia, the parasite lives in the intestine and is passed in feces. Because an outer shell protects the parasite, it can survive outside the body and in the environment for long periods of time — often several months or even a year or more.