You're Never Too Cool for Pneumonia

One of the crucial interventions to undertake after a person suffers cardiac arrest is therapeutic hypothermia. This intervention cools the body temperature (by a few degrees Centigrade) in order to minimize damage to then brain that might have occurred during the period of time the person was deprived of oxygen and after circulation has been restored. 

There are several means to achieve a lowered body temperature and usually include either the insertion of a cooling catheter in a major vein or a special cooling blanket. 

One of the caveats to therapeutic hypothermia is that it increases the risk of infection. A recent systematic review and meta-analysis published in Critical Care Medicine, tries to asses the magnitude of this risk. 

Pooling the results of prior research, as was done in this paper, revealed that therapeutic hypothermia increases the risk of pneumonia and sepsis. This is not a surprising finding given the impact cold temperatures can  have on the immune system. Specifically, hypothermia blunts the ability of cells to employ specific cytokines thus rendering the individual in a net state of immunosupression. 

This finding illustrates the delicate balance physicians must strike in order to optimally treat a patient, continually weighing risks versus benefits. In the end, therapeutic hypothermia--for those who need it--confers too high of a  benefit to be jettisoned secondary to a heightened risk of infection. 

Legionairre's Disease: Three Rivers Nurture It

Today, the Department of Veterans Affairs conceded negligence in one of the fatal cases of hospital-acquired Legionnaire's Disease that have plagued the VA in Pittsburgh. In total 21 cases have been identified.

Irrespective of the issues regarding the VA, which likely resulted in the resignations of regional and local VA personnel, the fact remains that the Pittsburgh area is rife with Legionella. In fact, if taken as a state, the city of Pittsburgh would rank high as a state. Perhaps the confluence of our famed three rivers provide the perfect environment for Legionella.

In Pittsburgh, every case of pneumonia is considered a potential Legionella case. 

MRSA Probably Attends Every Super Bowl

As everyone was watching the Super Bowl today, I thought it appropriate to review an infection that is common in those who play football: MRSA skin and soft tissue infections.

One of the most famous associations of this organism with a football team was with the 2003 St. Louis Rams. In that incident, MRSA skin infections occurred in 9% of the Rams with--ominously--42% of players and  staff colonized in their nasal passages. 

More recent studies, have confirmed similarly high prevalence of infection with MRSA in high school football players as well.

Skin abrasions (i.e. turf burn) are thought to predispose to infections while the close contact amongst players coupled with suboptimal hygiene predisposes to colonization.

MRSA--another reason to prefer skateboarding (my favorite sport).

Going Viral: Gossip vs. Ebola

In the sci-fi movie I Am Number Four one of the characters states that "gossip spreads like Ebola." The point being made is that gossip spreads quickly and widely. Although this type of spread is definitely applicable to gossip, it's really a false analogy because Ebola, thankfully, doesn't spread like gossip. 

Ebola outbreaks, which can be explosive, do not sustain themselves. The highly lethal virus appears to spillover from its animal reservoir (probably bats) to apes, monkeys, antelopes, and humans for an unknown reason. Once in a human population, it often exploits lax care practices that expose caretakers--including healthcare personnel--to bodily fluids. In fact, once minimal infection control procedures are instituted, new infections cease.

Additionally, diseases which kill fast with severe symptoms can strictly delimit the ability of the virus to find new individuals to infect. The fact that one is basically confined to a bed with Ebola coupled to the fact that Ebola transmission is via bodily fluids, provides little opportunity to spread the virus beyond close contacts.

Understanding the cycle of why Ebola outbreaks is the subject of some fascinating research (see Spillover) but, barring some mutations, gossip is more viral than the Ebola virus.

Is that Justinian's Plague Caught in-between Your Teeth?

Justinian's Plague, long thought to be the result of infection with Yersinia pestis, was responsible for killing approximately 50 million individuals in 541. Justinian's plague represented the 1st pandemic of plague and was followed about 800 years later by the more famous 2nd plague pandemic, The Black Death. 

In 576, about 35 years following this outbreak, the Roman Empire fell and some historians credit the plague's decimation of the population with weakening the already ailing Empire to the point where it was unable to fend off barbarian attacks (see Justinian's Flea). 

Using a remnant of a tooth found in a burial pit in Germany that dates from the time of Justinian, a research team was able to extract the DNA of the plague bacillus from dental pulp confirming that Y.pestis indeed was the culprit organism. 

It's interesting to imagine what the fate of the world would have been had this plague not occurred. I tend to think that the Roman Empire was already on a death spiral and the plague may only have served to hasten its fall.

Epidemics and their impact on history are a fascinating topic and one of the reasons the subject provides endless enjoyment for me.