Plague Gives Surprises in the First Decade of the 21st Century in the United States and Worldwide

Abstract

Abstract. Plague is an ancient disease caused by the bacterium Yersinia pestis and transmitted by rodent flea bites that continues to surprise us with first-ever events. This review documents plague in human cases in the 1st decade of the 21st century and updates our knowledge of clinical manifestations, transmission during outbreaks, diagnostic testing, antimicrobial treatment, and vaccine development. In the United States, 57 persons were reported to have the disease, of which seven died. Worldwide, 21,725 persons were affected with 1,612 deaths, for a case-fatality rate of 7.4%. The Congo reported more cases than any other country, including two large outbreaks of pneumonic plague, surpassing Madagascar, which had the most cases in the previous decade. Two United States scientists suffered fatal accidental exposures: a wildlife biologist, who carried out an autopsy on a mountain lion in Arizona in 2007, and a geneticist with subclinical hemochromatosis in Chicago, who was handling an avirulent strain of Y. pestis in 2009. Antimicrobial drugs given early after the onset of symptoms prevented many deaths; those recommended for treatment and prophylaxis included gentamicin, doxycycline, and fluoroquinolones, although fluoroquinolones have not been adequately tested in humans. Fleas that do not have their guts blocked by clotted blood meals were shown to be better transmitters of plague than blocked fleas. Under development for protection against bioterrorist use, a subunit vaccine containing F1 and V antigens of Y. pestis was administered to human volunteers eliciting antibodies without any serious side effects. These events, although showing progress, suggest that plague will persist in rodent reservoirs mostly in African countries burdened by poverty and civil unrest, causing death when patients fail to receive prompt antimicrobial treatment.

Seroprevalence and spatial distribution dynamics of Yersinia pestis antibodies in dogs and cats from plague foci in the State of Ceará, Northeastern Brazil

“…Plague persists in natural foci in many countries worldwide. As yet, the accumulated technological advances and scientific knowledge have not been enough to eradicate it 1,2 . Human cases of the disease are recorded annually in several countries in Africa, Asia, and the Americas…”

Identification of host factors required for Yersinia pestis macrophage intracellular survival and their impact on vacuole maturation, acidification and trafficking.

“…Globally, plague naturally occurs in the rodent population on every inhabited continent except Australia [5]. The World Health Organization estimates ~2,000 to 4,000 cases of human plague occur annually [5,6,14]. A recent review by Butler T et al, 2013, ranked the top twelve countries by human plague cases; China and the United States are seven and eleven, respectively [5].…”

“…Globally, plague naturally occurs in the rodent population on every inhabited continent except Australia [5]. The World Health Organization estimates ~2,000 to 4,000 cases of human plague occur annually [5,6,14].…”

“…Y. pestis is a zoonotic pathogen, cycling between the rodent (reservoir host) and the flea transmission vector [1]. The bacterium is endemic throughout rodent populations around the world, including the western United States [4,5]. Incidence of human plague has been increasing, suggesting that plague is a re-emerging pathogen, and not a historic disease [5,6].…”

“…The bacterium is endemic throughout rodent populations around the world, including the western United States [4,5]. Incidence of human plague has been increasing, suggesting that plague is a re-emerging pathogen, and not a historic disease [5,6]. Y. pestis has been used as a biological weapon and is considered by the U.S. federal government as a high risk for future use as a bioterrorism agent (Y. pestis is a Tier 1 Category A Select Agent) [7].…”