The Real Crazy Train: Measles

Yet another large measles exposure occurred in this country as the result of an unvaccinated individual contracting the illness while in Asia. 

The patient, who is a college student in California, rode a public transportation train and potentially exposed thousands of individuals to the virus, which can be deadly in select cases.

This incident has several aspects that worth highlighting:

• Though measles has been nearly eradicated from the US that is not the case in the rest of the world
• Unvaccinated individuals, who may have a relatively low (but not zero) risk of contracting the disease in the US, are at a high risk of infection when traveling to areas in which measles is still present and human populations are not immunized to a high degree, i.e. herd immunity has not been achieved
• Measles is extremely contagious and if exposed individuals were not adequately vaccinated, for personal reasons or because they are less than 1 year of age, they may contract measles

The bottom line: Measles is too contagious of a disease for the human population to become lax about.

I Sense Your Skin

Tonight, I attended one of the meetings of the University of Pittsburgh School of Medicine's "Bug Club". The members of this club are largely 1st and 2nd year Pitt med students who have a general interest in infectious diseases, especially of the tropical flavor.

The focus of the meeting tonight was on schistosomiasis, an awesome disease caused by a parasitic worm that jumps between humans and snails. 

One of the most intriguing aspects of this disease is how the worm finds its human host. Schistosomes emerge from snails in freshwater and, after finding a human, penetrate human skin to begin the process of infection. To detect that a human is in their environ, the organism "smells" human skin, i.e. the molecules on the skin of a human (e.g. linoleic acid). This attraction is so great that it sometimes prompts them to reverse the direction in which they are swimming.

Such an awesome proclivity--and "desire"--to infect humans by microbes is what makes my job as an infectious disease physician so much fun. I get to battle these things! 

UTIs Can Really Drive You Crazy

When a person with a known psychotic disorder has an exacerbation of their illness one often tries to determine hear the inciting cause might be. Did the person stop their medications, experience a major life stressor, or use an illicit substance? Is their condition progressing?

A new study identifies a potential cofactors that may have been overlooked: urinary tract infections. 

In a study published in the Journal of Clinical Psychiatry, 21% of those presenting with a psychotic episode who were admitted to the hospital had evidence of a urinary tract infection (as determined by their urinanalysis). By comparison only 3% of controls displayed evidence of infection.

I think that this finding is very intriguing and has the potential to change practice. It is well established that urinary tract infections can induce delirium and exacerbate dementia, so it is not surprising that they may have the same effect in psychotic disorders. Whether the generalized inflammatory response induced by the infection or some other factor is responsible remains to be determined.

At the least, awareness and screening for urinary tract infection should be considered in the evaluation of psychotic patients presenting with worsening symptoms. 

Polio in Kabul: The Polio Hydra in Pakistan Strikes Again

The news that a polio case has occurred in Kabul is another setback for the eradication program. While Afghanistan has cases of polio annually--14 last year--none have occurred in Kabul since 2001. Almost all cases from 2013 were linked to Pakistan. Similarly, in this case, members of the patient's family reportedly travelled to the polio-endemic nation of Pakistan where the virus was contracted. 

To date this year, 2 cases of polio have occurred in Afghanistan while 7 have occurred in Pakistan. No other nations have reported cases. 

A case in the highly populated capital city is concerning because of the potential for the virus to spread and spark further cases. Accordingly, an immunization campaign in Kabul has been launched. 

This case illustrates the fact that Pakistan, an area rife with murderous violence against polio vaccinators, is the head of the hydra that must be severed to control this disease.

Antibiotic Resistance, the End of Precision Medicine, & Job Security

Today I came across an interesting perspective on antimicrobial resistance, a phenomenon that, as an infectious diseases physician, commands a great deal of my attention. In The Innovator's Prescription, the diagnosis of many infectious diseases is described as having moved from a stage in which diagnosis and treatment was intuitive, expert-led, and hypothesis-driven to a more precise stage in which diagnoses is largely exact and response to therapy predictable (think strep throat). 

The book goes on to make the point that antimicrobial resistance, by rendering our standard treatments obsolete, may reverse this trend relegating us back to a stage in which response to treatment is not predictable and treatment regimens may require a lot of expert-led contemplation and hypothesis testing (think multi-drug resistance Acinetobacter). 

At least this fascinating and dire analysis predicts job security for my colleagues and me.