The Germlines
The Podcast about the Movement of Infectious Diseases Through Populations and Across the Landscape
Podcaster: Michael Walsh
I am in the Department of Epidemiology and Biostatistics in the School of Public Health at the State University of New York, Downstate. I teach infectious disease epidemiology and conduct research on parasitism, vector-borne infections, and landscape epidemiology. I have a particular interest in disease ecologies and social and geographic health disparities.
PODCAST.GERMLINES.ORG
Germlines 11: Birds of a feather flock together: Avian influenza meta-analysis
This time on the Germlines I rejoined the cast of This Week in Virology to discuss controversial meta-analyses of several population-based studies of human H5N1 infection across varied geographies primarily in Southeast Asia. We discussed two papers. The first is entitled Seroevidence for H5N1 Influenza Infections in Humans: Meta-Analysis by Wang, et al. and can be found here. The second is entitled Mammalian-Transmissible H5N1 Influenza: Facts and Perspective by Osterholm and Kelley and can be found here. It was another fantastic discussion with the TWiV team covering important aspects of these seroepidemiologic studies and highlighting the conclusions we can confidently draw from these data.
This episode was recorded, produced and published by This Week in Virology and was titled, TWiV 173: Going to bat for flu research
Download | Duration: 01:57:24
Germlines #10: Mr. Smith Goes to Washington (Heights)
This time on the Germlines I had the great opportunity to join the outstanding cast of This Week in Virology to discuss some of the core concepts in epidemiology as well as some of its limitations. We also discussed the controversial H5N1 research ban by the National Science Advisory Board for Biosecurity. Vincent, Dickson, Alan, Rich, and I discussed the importance of carefully assessing causal claims, getting the metrics of occurrence right, and letting scientists do science. The TWiV team is a wonderful group, so it was an excellent discussion.
This episode was recorded, produced and published by This Week in Virology and was titled, TWiV 169: Epidemiology causes conclusions (p<0.05)
Download | Duration: 02:32:16
Germlines #9: Vaccines 101
This time on the Germlines I am giving an introduction to vaccines. We will cover what they are, how they work, and the extensive and rigorous research process they must complete in order to show they are safe and efficacious. This episode was inspired by my increasing dismay over the ongoing and growing lack of vaccination among populations that have more than adequate access to vaccines. This episode seeks to provide a scientific basis and clear explanation for the importance of vaccination. There is a saying in many parts of the world that goes, "Don't count your children until the measles have passed." I don't think there could be any message for vaccination that is more poignant than that. Vaccines have provided powerful landscapes of protection for many diseases. Let us not recreate new deadly landscapes of infection because we are misinformed.
Here is a link to extensive information on vaccination in general and the measles vaccine in particular at Infection Landscapes:
Measles Part 2: The Vaccine and the Control of a Killer
Here is a link to a very nice summary of herd immunity in the Vaccine Times:
Herd immunity
Here is a link to extensive information on vaccination in general and the measles vaccine in particular at Infection Landscapes:
Measles Part 2: The Vaccine and the Control of a Killer
Here is a link to a very nice summary of herd immunity in the Vaccine Times:
Herd immunity
Download | Duration: 01:04:15
Germlines #8: Survivorbug 2: Home is Where the Hearth Is
This time on the Germlines we revisit the primary vector of Chagas disease in South America, Triatoma infestans. We will review another paper by the same group we reviewed last time in the context of sylvan refuge populations of T. infestans, which we discussed may pose a threat to the effectiveness of vector elimination insecticide programs. This time we discuss those characteristics specific to the home and domestic environments that are favorable to infestations with this reduviid bug. This paper is entitled, Factors Affecting Infestation by Triatoma infestans in a Rural Area of the Humid Chaco in Argentina: A Multi-model Inference Approach, and was published October 18, 2011 in PLoS Neglected Tropical Diseases. It is available for free here.
You can find background information on Chagas disease at Infection Landscapes: Trypanosomiasis Part 2: Chagas disease
For those interested, I am also including some links on logistic regression and negative binomial regression.
Download | Duration: 00:39:29
Germlines #7: Survivorbug: Off the Grid with Triatoma
This time on the Germlines, I will discuss the occurrence of sylvan, or wild, foci of Triatoma infestans in the Gran Chaco in nothern Argentina. This reduviid bug is the most important vector for Chagas disease in South America, and these findings have important implications for the landscape epidemiology of Chagas disease in this region. The podcast is based on a publication in this month's PLoS Neglected Tropical Diseases entitled, Hidden Sylvatic Foci of the Main Vector of Chagas Disease Triatoma infestans: Threats to the Vector Elimination Campaign? The paper is open access and can be obtained freely here: PLoS Neglected Tropical Diseases paper
You can find background information on Chagas disease at Infection Landscapes: Trypanosomiasis Part 2: Chagas disease
Triatoma infestans:
Download | Duration: 00:34:58
Germlines #6: Phylogeny of Place and Plague
This week on the Germlines, I look at the geographic lines of distinction in the molecular epidemiology of Yersinia pestis in one of the world's hotspots of plague activity: Madagascar. The podcast is based on a paper published in this month's in PLoS Neglected Tropical Diseases. It is entitled, Phylogeography and molecular epidemiology of Yersinia pestis in Madagascar. You can obtain this paper for free here: PLoS NTD paper.
You can find background information on plague at Infection Landscapes: Plague
If you are interested in some background information on the processing of single nucleotide polymorphisms (SNPs) or multi-locus variable number tandem repeat analysis (MLVA) you can find it at the links below:
SNPs
Download | Duration: 00:21:58
Germlines #5: Cholera: A River Runs Through It...
In episode number 5 of the Germlines, I discuss the relationship between river discharge into marine environments and the proliferation of cholera in coastal areas. This podcast is based on a recent paper published in the American Journal of Tropical Medicine and Hygiene entitled, Warming oceans, phytoplankton, and river discharge: Implications for cholera outbreaks. Unfortunately, this is not an open access paper, but I am posting the Pubmed link with reference and abstract here.
You can find detailed background information on cholera at Infection Landscapes:
Download | Duration: 00:31:31
Germlines #4: A class-ic virus in Long Island
This time on the Germlines, I talk about West Nile virus transmission in Suffolk County, New York. Specifically, we will look at the interplay between socioeconomic status and aspects of the physical landscape in the identification of geographic risk for human infection. The podcast is based on the recent paper in PLoS One entitled, Predictive Mapping of Human Risk for West Nile Virus (WNV) Based on Environmental and Socioeconomic Factors. You can obtain this paper for free here: PLoS One Paper.
You can find detailed information on West Nile virus at Infection Landscapes:
While not necessary for listening to this podcast, if you are interested in more detail on the math used in this paper:
You can find background on logistic regression here.
And you can find background on principal component analysis here.
Download | Duration: 00:37:11
Germlines #3: A man and a mosquito walk into a bar...
This time on Germlines I will discuss the dynamics of human and mosquito population mixing in the transmission and maintenance of vector-borne infections, with the major focus on dengue fever. We are discussing a very interesting paper I came across recently that was published in 2009 in PLoS One. This is an open access journal so you can obtain a pdf of the paper here: PLoS One Paper: Man bites mosquito
Here are links to background reading at Infection Landscapes (www.infectionlandscapes.org):
Finally, while not necessary for listening to and understanding the content of this podcast, for anyone interested in a very basic outline of the epidemiologic deterministic models (as opposed to statistical models) used in this paper there is a nice website with some background information here. And a quick thumbnail sketch of the equations behind the specific SEIR model can be found here.
Download | Duration: 01:06:18
Germlines #2: Water, Mountains and Malaria, Oh My!
This time on Germlines I cover land topography, the flow of water through the landscape and the occurrence of malaria in the western Kenyan highlands. The basis for the discussion is a paper published in the open access journal, Malaria Journal. You can obtain a free pdf of the paper here.
Here are links to background malaria reading at www.infectionlandscapes.org:
Malaria vector
Malaria disease
Malaria landscape
Finally, for anyone interested in the math behind the modeling used in this study here is the wikipedia site for the negative binomial distribution, which I think is adequate.
Download | Duration: 00:34:24