Midgut flea proventriculus. Medical search. Frequent questions

Plague is an acute, contagious, febrile illness usually transmitted to humans by the bite of an infected flea. (medscape.com)
Plague is most often vector borne, transmitted by fleas, to a variety of rodent populations. (medscape.com)
Of the 1500 flea species identified, only 30 of them have been shown to act as vectors of plague. (medscape.com)
Oriental rat flea (Xenopsylla cheopis), the primary vector of plague, engorged with blood. (medscape.com)
Plague vectors Several species of fleas can transmit the plague. (gradebuddy.com)
It can harbor fleas infected with Yersinia pestis, the plague bacillus. (medscape.com)
The pathophysiology of plague basically involves two phases-a cycle within the fleas and a cycle within humans. (medscape.com)
Role of the Yersinia pestis hemin storage (hms) locus in the transmission of plague by fleas. (medscape.com)
Early-phase transmission of Yersinia pestis by unblocked fleas as a mechanism explaining rapidly spreading plague epizootics. (medscape.com)
Travel to endemic areas within and outside the United States, history of a flea bite, close contact with a potential host, or exposure to dead rodents or rabbits should raise suspicion for plague. (medscape.com)
Plague initially occurred as a flea-borne septicemic disease. (medscape.com)

It is a facultative anaerobic organism that can infect humans via the Oriental rat flea (Xenopsylla cheopis). (wikipedia.org)
The classic vector is the oriental rat flea Xenopsylla cheopis . (medscape.com)

Yersinia pestis is a parasite of its host, the rat flea, which is also a parasite of rats, hence Y. pestis is a hyperparasite. (wikipedia.org)
pFra codes for a phospholipase D that is important for the ability of Y. pestis to be transmitted by fleas. (wikipedia.org)
Y. pestis causes diseases through a bite of an infected rat or flea, but can also be transmitted by air. (kenyon.edu)
Y. pestis grows in the midgut and eventually blocks the proventriculus, starving the flea for blood. (kenyon.edu)
Hinnebusch BJ, Rudolph AE, Cherepanov P, Dixon JE, Schwan TG, Forsberg A. Role of Yersinia murine toxin in survival of Yersinia pestis in the midgut of the flea vector. (medscape.com)
Transmission of Yersinia pestis from an infectious biofilm in the flea vector. (medscape.com)

The blockage drives the flea wild with hunger since it cannot get food into the midgut. (gradebuddy.com)
The key to the organism's virulence is the phenomenon of "blockage," which aids the transmission of bacteria by fleas. (medscape.com)

[ 10 ] Survival of the bacillus in nature depends on flea-rodent interaction, and human infection does not contribute to the bacteria's persistence in nature. (medscape.com)

Hemoglobin from the RBCs, bacteria and other debris begin to accumulate on the proventriculus. (gradebuddy.com)
To cause the disease, about 25 pathogenic organisms are needed, but when the flea expels the gut contents, there are about 100,000 bacteria introduced into the host. (gradebuddy.com)
The detritus on the spines are bacteria and broken red blood cells.Symptoms The flea usually bites areas in the armpit or groin and the injected pathogens move via the circulatory system to the nearest lymph gland. (gradebuddy.com)
After ingestion of infected blood, the bacteria survive in the midgut of the flea owing to a plasmid-encoded phospholipase D that protects them from digestive juices. (medscape.com)

[ 9 ] These acquired genetic changes have allowed the pathogen to colonize fleas and to use them as vectors for transmission. (medscape.com)

Eventually, the proventriculus becomes blocked as does the rest of the gut. (gradebuddy.com)

Fleas can become infected by taking the blood of other infected animals. (kenyon.edu)
The infected flea, needing more blood, moves off the cooling body to find another host. (gradebuddy.com)
The flea continues to feed and the blood accumulates in the esophagus. (gradebuddy.com)
It connects the mouth to the midgut and is responsible for breaking red blood cells to release their nutrients. (gradebuddy.com)

There is cosmic justice as the flea also dies, not from the disease, but from hunger. (gradebuddy.com)

Flea proventriculus The image on the left side shows the proventriculus. (gradebuddy.com)

Yersinia pestis is a parasite of its host, the rat flea, which is also a parasite of rats, hence Y. pestis is a hyperparasite. (wikipedia.org)
It can harbor fleas infected with Yersinia pestis, the plague bacillus. (medscape.com)
Within the blocked flea model, Yersinia murine toxin (Ymt) has been shown to be important for facilitating colonization of the midgut within the flea . (bvsalud.org)

9] These acquired genetic changes have allowed the pathogen to colonize fleas and to use them as vectors for transmission. (medscape.com)
is thought to have evolved over the last 1500C20 000 years from the enteropathogen, [8], to become a flea-vectored pathogen lethal to man [9,10]. (ubatubasat.com)
Whilst the physiological and molecular mechanisms of blocked flea transmission are well characterized, the pathogen-vector interactions have not been elucidated for EPT. (bvsalud.org)

Our results show that Ymt was not required for EPT by either flea species. (bvsalud.org)

The classical 'blocked flea ' paradigm, by which a blockage forms in the flea 's proventriculus on average 1-2 weeks post- infection (p.i.), forces starving fleas to take multiple blood meals , thus increasing opportunities for transmission . (bvsalud.org)