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Contagions is place to collect some thoughts on history, infectious disease and science in general. My primary interests are in the history of plague, and the impact of malaria, smallpox, and yellow fever on the Americas.

Michelle Ziegler
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  • August 24, 2013
  • 11:23 PM

Western Iranian Plague Foci Still Active, 2011-2012

by Michelle Ziegler in Contagions

In a letter in this month’s Emerging Infectious Diseases, an Iranian and French team of epidemiologists report that the old plague focus in western Iran bordering Kurdistan is still active. Between 1947 and 1966 there were nine human plague epidemics causing 156 human deaths.  The last recorded human case occurred in 1966 and in animals […]... Read more »

Esamaeili S, Azadmanesh K, Naddaf SR, Rajerison M, Carniel E, & Mostafavi E. (2013) Serologic survey of plague in animals, Western iran. Emerging infectious diseases, 19(9). PMID: 23968721  

  • August 8, 2013
  • 09:30 AM

Antibiotic Resistance, Agriculture, and the Plague

by Michelle Ziegler in Contagions

Antibiotics have ended the uncontrollable outbreaks of plague in humans that stalked our ancestors. Today, outbreaks are usually snuffed out after a couple of cases with antibiotic treatment of patients, prophylactic treatment of contacts and vector control. Our greatest risks from plague today are a pneumonic plague outbreak/attack and the emergence of antibiotic resistance. Beginning […]... Read more »

Prentice MB, James KD, Parkhill J, Baker SG, Stevens K, Simmonds MN, Mungall KL, Churcher C, Oyston PC, Titball RW.... (2001) Yersinia pestis pFra shows biovar-specific differences and recent common ancestry with a Salmonella enterica serovar Typhi plasmid. Journal of bacteriology, 183(8), 2586-94. PMID: 11274119  

  • June 10, 2013
  • 02:54 AM

Trench Fever: An Ancient Zoonosis

by Michelle Ziegler in Contagions

Trench fever is an ancient disease with a surprisingly short history. Named after its discovery in the trenches of World War I, its case history is only about a century old. Yet, the louse transmitted Bartonella quintana that causes trench fever has been found in human remains as old as 4000 years and is one […]... Read more »

Li H, Liu W, Zhang GZ, Sun ZZ, Bai JY, Jiang BG, Zhang YY, Zhao XG, Yang H, Tian G.... (2013) Transmission and maintenance cycle of Bartonella quintana among rhesus macaques, China. Emerging infectious diseases, 19(2), 297-300. PMID: 23347418  

  • April 7, 2013
  • 01:55 PM

Fleshing out Yersinia pestis

by Michelle Ziegler in Contagions

Up until a few months ago there were a few representative samples of the Yersinia pestis genome. Important windows into its secrets, but windows none the less. In January a Chinese group remedied this situation by expanding the number of fully sequenced genomes from 15 to 133 (Cui et al, 2013).  China supplied 107 genomes [...]... Read more »

Cui, Y., Yu, C., Yan, Y., Li, D., Li, Y., Jombart, T., Weinert, L., Wang, Z., Guo, Z., Xu, L.... (2012) Historical variations in mutation rate in an epidemic pathogen, Yersinia pestis. Proceedings of the National Academy of Sciences, 110(2), 577-582. DOI: 10.1073/pnas.1205750110  

Rajanna C, Ouellette G, Rashid M, Zemla A, Karavis M, Zhou C, Revazishvili T, Redmond B, McNew L, Bakanidze L.... (2013) A Strain of Yersinia pestis With a Mutator Phenotype from the Republic of Georgia. FEMS microbiology letters. PMID: 23521061  

Vogler, A., Chan, F., Nottingham, R., Andersen, G., Drees, K., Beckstrom-Sternberg, S., Wagner, D., Chanteau, S., & Keim, P. (2013) A Decade of Plague in Mahajanga, Madagascar: Insights into the Global Maritime Spread of Pandemic Plague. mBio, 4(1). DOI: 10.1128/mBio.00623-12  

  • January 20, 2013
  • 06:28 PM

Reactivation of Ancient Plague Foci in Libya, 2009

by Michelle Ziegler in Contagions

Plague has been called a re-emerging disease primarily because cases have begun to appear in areas where plague has been absent for decades. Two recent surprising outbreaks occurred in Algeria, where plague had been absent for over 50 years, and in Libya after a 25 year absence. A team led by the Institut Pasteur explored [...]... Read more »

Cabanel, N., Leclercq, A., Chenal-Francisque, V., Annajar, B., Rajerison, M., Bekkhoucha, S., Bertherat, E., & Carniel, E. (2013) Plague Outbreak in Libya, 2009, Unrelated to Plague in Algeria. Emerging Infectious Diseases, 19(2), 230-236. DOI: 10.3201/eid1902.121031  

  • November 28, 2012
  • 01:17 AM

Siberian Mummy Yields 300-year-old Smallpox DNA

by Michelle Ziegler in Contagions

It was the mass grave that got their attention. Four bodies crammed into one casket, with one child outside but with the casket. Multiple graves are not common in Yakutia, Siberia. Examination of the late 17th to early 18th century mummies indicates that burial came quickly after death. The casket contains one adult male over [...]... Read more »

Biagini, P., Thèves, C., Balaresque, P., Géraut, A., Cannet, C., Keyser, C., Nikolaeva, D., Gérard, P., Duchesne, S., Orlando, L.... (2012) Variola Virus in a 300-Year-Old Siberian Mummy. New England Journal of Medicine, 367(21), 2057-2059. DOI: 10.1056/NEJMc1208124  

  • November 4, 2012
  • 08:24 PM

Leprosy in Medieval Scandinavia

by Michelle Ziegler in Contagions

Leprosy is an ancient disease. References to leprosy and the social stigma attached to it go back to 600 BC from India and in the Old Testament. However, like the plague, it was not until relatively late (1873) that the term leprosy became attached to a particular microbe, Mycobacterium leprae. Although some medieval descriptions suggest [...]... Read more »

Economou, C., Kjellström, A., Lidén, K., & Panagopoulos, I. (2013) Ancient-DNA reveals an Asian type of Mycobacterium leprae in medieval Scandinavia. Journal of Archaeological Science, 40(1), 465-470. DOI: 10.1016/j.jas.2012.07.005  

  • October 22, 2012
  • 08:00 AM

Enzootic Plague and the Great Gerbil of Central Asia

by Michelle Ziegler in Contagions

Meet the Great Gerbil The Great Gerbil of Central Asia is not much like the little gerbils found in American pet stores. This bad boy can get as long as 13 inches head to tail, about the size of a  prairie dog or large black rat. It holds a similar ecological niche as the prairie [...]... Read more »

  • September 16, 2012
  • 10:00 AM

Insights from Plague Genomics, Part 1: The Chromosome

by Michelle Ziegler in Contagions

Most of the news lately has been about the plague phylogenetic tree produced by looking at single nucleotide polymorphisms (SNPs). The plague tree is remarkably simple and can lead to the mistaken impression that the rest of plague genomics are/will be simple. Michel Drancourt has recently compiled an array of genomic information that shows that [...]... Read more »

Drancourt, M. (2012) Plague in the genomic era. Clinical Microbiology and Infection, 224-230. info:/

  • August 15, 2012
  • 08:00 AM

When Yellow Fever Came to the Americas

by Michelle Ziegler in Contagions

In the early Americas, nothing scared people more than when Yellow Jack came knocking at the door of their city. Yellow Jack, or as we know it better today Yellow Fever, has rightly been called the plague of the Americas. It has long been assumed that yellow fever came to the Americas with its vector, [...]... Read more »

J E Bryant, E C Holmes, & A D T Barrett. (2007) Out of Africa: A Molecular Perspective on the Introduction of Yellow Fever Virus into the Americas. PLOS Pathogens, 3(5). info:/doi:10.1371/journal.ppat.0030075

Auguste A. J., Lemey P., Pybus O. G., Suchard M. A., Salas R. A., Adesiyun A. A., Barrett A. D., Tesh R. B., Weaver S. C., & Carrington C. V. F. (2010) Yellow Fever Virus Maintenance in Trinidad and Its Dispersal throughout the Americas. Journal of Virology, 84(19), 9977. DOI: 10.1128/JVI.00588-10  

  • August 7, 2012
  • 08:00 AM

The Landscape of Super-Spreading

by Michelle Ziegler in Contagions

Super-spreading individuals and disease hot spots have been known for over a century, but rarely have they been considered together. Sara Paull and colleagues [1] have pulled together all of the recent work the ecology of disease hot spots and transmission heterogeneity (super spreading) to explore the continuum between individual transmission heterogeneity and the landscape [...]... Read more »

  • July 29, 2012
  • 05:34 PM

Metagenomics, Lyme Disease, and the Tyrolean Iceman’s Tattoos

by Michelle Ziegler in Contagions

When the genetic analysis of the 5,300 year old Tyrolean Iceman, better known as Ötzi, was published in February, most of the attention was naturally focused on his genomic DNA. His genomic DNA produced some interesting results: he had brown eyes, blood type O+, was probably lactose intolerant and from a southern European gene pool. [...]... Read more »

Keller, A., Graefen, A., Ball, M., Matzas, M., Boisguerin, V., Maixner, F., Leidinger, P., Backes, C., Khairat, R., Forster, M.... (2012) New insights into the Tyrolean Iceman's origin and phenotype as inferred by whole-genome sequencing. Nature Communications, 698. DOI: 10.1038/ncomms1701  

  • June 28, 2012
  • 08:30 AM

Plague at the Siege of Caffa, 1346

by Michelle Ziegler in Contagions

The first stage of the Black Death among Europeans was said to begin with the whoosh of a Mongol trebuchet. Gabriele De’ Mussi, a lawyer from near Genoa writing in about 1348, is believed to have recorded the account of the earliest use of plague as  weapon of war at Caffa in 1346. “The dying [...]... Read more »

Wheelis M. (2002) Biological warfare at the 1346 siege of Caffa. Emerging infectious diseases, 8(9), 971-5. PMID: 12194776  

  • June 10, 2012
  • 02:20 AM

Achtman on Plague Evolution

by Michelle Ziegler in Contagions

Mark Achtman who led the international team that assembled the phylogenetic tree for Yersinia pestis participated in a Royal Society meeting on ‘Immunity, infection, migration and human evolution’ in June 2011. Achtman’s contribution placed plague evolution within the context of other ‘monomorphic’ pathogens. Here are some of my notes from his published contribution: Monomorphic pathogens [...]... Read more »

Achtman, M. (2012) Insights from genomic comparisons of genetically monomorphic bacterial pathogens. Philosophical Transactions of the Royal Society B: Biological Sciences, 367(1590), 860-867. DOI: 10.1098/rstb.2011.0303  

Morelli G, Song Y, Mazzoni CJ, Eppinger M, Roumagnac P, Wagner DM, Feldkamp M, Kusecek B, Vogler AJ, Li Y.... (2010) Yersinia pestis genome sequencing identifies patterns of global phylogenetic diversity. Nature genetics, 42(12), 1140-3. PMID: 21037571  

Haensch S, Bianucci R, Signoli M, Rajerison M, Schultz M, Kacki S, Vermunt M, Weston DA, Hurst D, Achtman M.... (2010) Distinct clones of Yersinia pestis caused the black death. PLoS pathogens, 6(10). PMID: 20949072  

  • May 7, 2012
  • 01:02 AM

Leptin: Linking Malnutrition and Vulnerability to Infection

by Michelle Ziegler in Contagions

The correlation between malnutrition and vulnerability to infection has been well established (discussed previously here). While the immune dysfunction could be characterized it was not until the last 10-15 years that an exact mechanism began to resolve. It all began with the discovery of a new hormone called leptin from an unexpected place, adipose tissue [...]... Read more »

Cava, A., & Matarese, G. (2004) The weight of leptin in immunity. Nature Reviews Immunology, 4(5), 371-379. DOI: 10.1038/nri1350  

Procaccini C, Jirillo E, & Matarese G. (2012) Leptin as an immunomodulator. Molecular aspects of medicine, 33(1), 35-45. PMID: 22040697  

  • April 29, 2012
  • 10:30 AM

Tracking a Live Yersinia pestis Infection with Bioluminescence

by Michelle Ziegler in Contagions

The day has finally arrived when an experimental infection can be tracked real-time over the entire course of the infection. Developing a natural history of a rapidly lethal infectious disease has been a challenge because individual variation clouds the progression and individuals can only be studied after death. The traditional method to study these infections [...]... Read more »

  • March 23, 2012
  • 08:00 AM

Primary Pneumonic Plague Transmission in the USA, 1900-2009

by Michelle Ziegler in Contagions

Pneumonic plague is a difficult phenomenon to model. We really don’t have much data from the modern medical era. Hinckley et al. (2012) argue that most of the data studied to date has been biased by taking it from well-established epidemics. To better study all transmission conditions, they gathered all of the cases of primary [...]... Read more »

Hinckley AF, Biggerstaff BJ, Griffith KS, & Mead PS. (2012) Transmission dynamics of primary pneumonic plague in the USA. Epidemiology and infection, 140(3), 554-60. PMID: 21733272  

  • March 14, 2012
  • 08:15 PM

What makes a Super-Spreader?

by Michelle Ziegler in Contagions

Parameters that should be theoretically equal often aren’t so in the real world. Ideally everyone should have the same potential to transmit an infection during a given outbreak, but it has long been observed that this isn’t true. Super-spreaders play an extraordinary role in driving outbreaks of infectious disease. A super-spreader is a person who [...]... Read more »

Stein RA. (2011) Super-spreaders in infectious diseases. International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases, 15(8). PMID: 21737332  

Galvani AP, & May RM. (2005) Epidemiology: dimensions of superspreading. Nature, 438(7066), 293-5. PMID: 16292292  

  • February 27, 2012
  • 12:00 AM

Gothic Epidemiology? or Gothic Historiography?

by Michelle Ziegler in Contagions

I was reading David Mengel’s recent article on plague in Bohemia and he kept referring to this apparently well-known concept, gothic epidemiology. Being the early medieval geek that I am, my first thought was Ostrogoth or Visigoth, and what do they have to do with epidemiology, especially in Bohemia? Feeling that I was clearing missing [...]... Read more »

  • February 25, 2012
  • 11:20 PM

Generating Immunity to the Plague

by Michelle Ziegler in Contagions

Its pretty amazing that we still don’t have a vaccine against the plague. Work still goes on and it hasn’t been easy by any means, but it really isn’t a priority that you hear about much. Vaccines developed to date have issues with side effects and the need for repeat immunizations to be protective against [...]... Read more »

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