Initially, it seemed like just another, now annual, outbreak. Plague is endemic in Madagascar, producing about 400 infections per year. As of October 13, there were 684 cases infections with 57 deaths. Four days later (the weekend update), the case number jumped to 804 cases and 74 deaths for a 9.3% mortality rate and pneumonic plague reached 74%... Continue Reading →
Multi-strain Plague Blooms Over Landscapes
Two articles have come to my attention over the couple months that argue strongly for an environmental role in plague epidemics/epizootics over clonal expansion. Taken together these studies suggest that multiple strains of Yersinia pestis percolate out of multiple reservoirs at the same time. The strongest support comes from Madagascar where ten MLVA defined strains from... Continue Reading →
A Synopsis of an Unusual Pneumonic Plague Outbreak in Madagascar, 2011
Plague appears in Madagascar every year, but it can still come as a surprise. It did in the January of 2011 when it appeared in an area of northern Madagascar that had never had an outbreak before. Not only was it a new area, but all of the cases were pneumonic. Not one case of... Continue Reading →
Yersinia pestis found in human fleas, Madagascar 2013
Madagascar is consistently one of the top two countries in Africa (and usually the world) in cases of plague, caused by Yersinia pestis. For five years prior to January 2013, Madagascar registered 312 to 648 cases per year, with a majority being laboratory confirmed of which >80% were bubonic plague. Of the multiple reservoir species in... Continue Reading →
Antibiotic Resistance, Agriculture, and the Plague
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... Continue Reading →
Fleshing out Yersinia pestis
by Michelle Ziegler 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... Continue Reading →