ERF of waterborne microbes

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Question

What are the dose-response functions of pathogens in drinking water?

Answer

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Rationale

Data

ERF of waterborne microbes(-)
ObsExposure agentResponseExposureExposure unitER functionScalingThresholdERFDescription
1campylobactercampylobacter infectioningestion?beta poisson approximationNone0.0110.024
2rotavirusrotavirus infectioningestion?exact beta poissonNone0.1910.167
3norovirusnorovirus infectioningestion?exact beta poissonNone0.0550.04
4cryptosporidiumcryptosporidium infectioningestion?exact beta poissonNone0.1760.115
5giardiagiardia infectioningestion?exponentialNone00.0199
6E.coli O157:H7E. coli infectioningestion?exact beta poissonNone9.160.157E. coli O157:H7 strain

⇤--arg6688: . Find out the units of the parameters to understand the functions precisely. --Jouni (talk) 12:54, 11 July 2019 (UTC) (type: truth; paradigms: science: attack)

----arg2087: . The ERF and Threshold numbers in the tables correspond to parameters called alpha and beta respectively in the papers cited below in the cases of campylo, rota, noro and crypto. The equations alpha and beta are used in in the papers don't (seem to) match the equations below. At least for campylo the equations are significantly more complicated. For giardia the value in ERF does seem to be used in the paper it's from in the way the exponential equation shows. In the paper it's marked as r, the probability of infection. The equation in the paper uses "mean number per portion" where Dose is in this equation. E.coli is the biggest mystery: I wasn't able to find the numbers in the table above from the paper sited for it at all. --Heta (talk) 10:32, 12 July 2019 (UTC) (type: truth; paradigms: science: comment)

In these equations, Param1 and Param2 are in Threshold and ERF columns, respectively.

  • Beta Poisson approximation: 1-(1+Dose/Param2)^-Param1
  • Exact beta Poisson: 1-exp(-(Param1/(Param1+Param2))*Dose)
  • Exponential: 1-exp(-Param1*Dose)
Pathogen Reference
Campylobacter [1]
Rotavirus [2]
Norovirus [3]
Cryptosporidium [4]
Giardia [5]
E.coli O157:H7 [6]

Calculations

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⇤--arg5268: . The code below is old and does not work with the new ERF table. --Jouni (talk) 12:54, 11 July 2019 (UTC) (type: truth; paradigms: science: attack)

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See also

References

  1. Teunis, P., van den Brandhof, W., Nauta, M., Wagenaar, J., van den Kerkhof, H. and van Pelt, W. 2005. A reconsideration of the Campylobacter dose–response relation. Epidemiol. Infec. 133, 583-592. DOI: https://doi.org/10.1017/S0950268805003912
  2. Teunis, P. F. M. and Havelaar, A. 2000. "The beta Poisson dose‐response model is not a single hit model."Risk Analysis 20(4): 513-520. https://doi.org/10.1111/0272-4332.204048
  3. Teunis P.F.M., Moe, C.L., Liu, P., Miller, S.E., Lindesmith, L., Baric, R.S., Le Pendu, J., Calderon, R.L. 2008. Norwalk Virus: How Infectious is It? Journal of Medical Virology 80:1468-1476. https://doi.org/10.1002/jmv.21237
  4. Teunis, P.F.M., Chappell, C.L., Okhuysen, P.C. 2002. Cryptosporidium Dose Response Studies: Variation Between Isolates. Risk Analysis 22(1) 175-183 https://doi.org/10.1111/0272-4332.00014
  5. Teunis, P.F.M., van der Heijden, O.G., van der Giessen, J.W.B., Havelaar, A.H. 1996. The dose-response relation in human volunteers for gastro-intestinal pathogens. RIVM report No. 284550002. http://hdl.handle.net/10029/9966
  6. Teunis, P., Takumi, K. and Shinagawa, K. 2004. "Dose response for infection by Escherichia coli O157:H7 from outbreak data." Risk Analysis 24(2): 401‐407. https://doi.org/10.1111/j.0272-4332.2004.00441.x