Mumps: Don't Call it a Comeback

In the midst of news regarding measles and pertussis, two diseases enjoying resurgences due to lack of immunity from lax vaccination attitudes (see this Pittsburgh Tribune Review article), mumps also appears to be making a comeback. In fact, however, the 2014 outbreaks at Fordham and Ohio universities are part of a trend that began in the US around 2006.

In contrast to the other vaccine preventable diseases, mumps appears to be somewhat mysterious in that it occurs in highly vaccinated populations and not in those lacking immunity. Such outbreaks didn't occur pre-2006 which leads to several questions: 

1. Has the mumps virus strain changed to a point where it is somewhat less likely to be stopped by the current vaccine's induced antibodies?
2. Do crowded conditions at college campuses somehow overwhelm immunity?
3. Are there super spreaders who shed high amounts of virus? 

Overall, though mumps is a much less virulent disease than measles and has less individual--and public health--import. 

Should Pneumococcal Meningitis Prompt a Public Health Response?

Here in Pittsburgh a 6 year old boy died from bacterial meningitis this week. There was some interest from the media and the county health department held a press conference to announce some of the specifics of the case, including the important fact that the culprit organism was treptococcus pneumoniae (the pneumococcus). As such, no major public health intervention--such as antibiotic prophylaxis--was needed. 

However, children dying of invasive pneumococcal disease is not something that should be considered commonplace in light of the availability of pneumococcal vaccines. The really are two pneumococcal vaccines that are relevant: the traditional 23-valent pneumococcal polysaccharide vaccine targeted primarily at the elderly and 13-valent (formerly 7) pneumococcal conjugate vaccine targeted primarily at children. 

While an important question will be whether the child was vaccinated and if the specific pneumococcus isolated was a vaccine serotype, I wonder what the pneumococcal vaccine rate is in his neighborhood. 

I think about this because of an innovative approach employed in Philadelphia for a similar problem that I once heard about in a lecture. In Philadelphia, rates of invasive pneumococcal disease are mapped with vaccination rates. Such an approach uncovers areas in which vaccine--which reduces carriage rate as well as infections--should be prioritized. The approach is reminiscent of the surveillance and containment approach used to eradicate smallpox. 

A Cocktail of HIV Cures

A few new developments regarding the potential for an HIV cure are sparking a round excitement. There are several manners in which an HIV cure--as opposed to a preventative vaccine--is being pursued. 

The first is in a manner such as with The Berlin Patient, a man who developed leukemia in the setting of HIV and underwent a bone marrow transplant with cells lacking the HIV co-receptor CCR5. This is the subject of a new book I'm eager to read. 

The other avenue is that taken by the Mississippi baby. In this case, a child born to an HIV positive mother--who did not receive prophylactic treatment--was immediately placed on antiretroviral therapy for a period of time. That treatment has since stopped and no detectable virus has been found in the child's blood. A similar procedure was recently reported in Long Beach. A larger trial is being planned. Similar results have been shown in adults in the Visconti cohort, albeit a small amount of viral material presents. 

The final approach is novel and involves using genetic engineering to remove the CCR5 co-receptor from a person's T-cells and then re-infusing them. Such infusions of T cells lacking this receptor were found to die much less slowly than their HIV-vulnerable counterparts, in the absence of treatment, and also to be safe.

Taken as a whole, the potential success of curative treatments and an efficacious vaccine have the potential to change the dynamics between HIV and the human race.

Steering the Antibiotic Enterprise

Today there have been multiple media stories regarding the misuse of antibiotics in hospitalized patients and the risk that this practice poses. Not only does it waste money, it sets up a scenario in which infections such as Clostridium difficult thrive. 

C.diff, as it is colloquially known, is a bacterium that can cause a range of symptoms from diarrhea to life-threatening intestinal perforation. It also adds significant days onto a hospital stay, can spread to other patients, and is expensive. 

The media attention is focused on a report from the CDC which studied the use of antibiotics in hospitals. What the CDC found is alarming:

• Over 50% of hospitalized patients receive an antibiotic of some sort
• Scrutinizing the use of vancomycin and the treatment of urinary tract infection revealed that treatment could have been improved in close to 40% of cases 
• Antibiotics prescribed for urinary tract infections were particularly egregious with many being prescribed without a definitive diagnosis (i.e. no symptoms, no culture ordered)
• Using mathematical tools, it was found that a 30% decrease in antibiotic use would decrease C.diff rates by a similar amount

The bottom line of this report is that antibiotic stewardship--something that is part of the daily routine of every infectious disease physician--is a key component of controlling the rates of C.diff, improving cost-effectiveness, and improving patient care. 

Vaccine Education Can't Cure Irrationality

A recent study on vaccine education yielded a paradoxical result. In those less likely to vaccinate their child, information aimed at illustrating the benefits of vaccines and debunking the fantastical "link" to autism actually strengthened their resolve against vaccines.

What this illustrates to me is that once one has committed to an irrational fixed belief, rational persuasion is not something that can be effective. Anti-vaccinationists, by their very position,  have declared that reason, logic, and evidence hold no sway with them. Because the benefits of vaccines are unequivocal and manifest for all to see, willful evasion must be occurring on some level. 

The anti-vaccine movement began, not in the modern era, but with the 1st vaccine (Jenner's smallpox vaccine). Today's movement is nothing more than an extension of that primitive phenomena which has, since its inception, stunted mankind's progress.