When it Comes to Tamiflu 48 Hours is just the Title of a Movie

One thing that I really annoys me is the common misconception that Tamiflu should only be used within 48 hours of symptom onset and is only able to diminish symptoms. While the strongest data supports the above two claims, there is evidence that Tamiflu confers additional--and potentially lifesaving--benefits.

What must be kept in mind is that when Tamiflu received FDA approval it was studied in uncomplicated influenza cases and was shown to be maximally (not exclusively) beneficial when administered within 48 hours of symptom onset. Severe cases were not included in those randomized controlled trials and, consequently, strong data regarding pneumonia and other severe complications of influenza do not really exist. 

The other element of this story is that because severe influenza is unequivocally life-threatenening it is not possible to conduct a placebo-controlled trial as withholding antiviral treatment from a severely ill individual can not be justified. 

While strong data (i.e. prospective, randomized, placebo-controlled) may not exist that does not mean no data exist. Retrospective data has shown Tamiflu to be beneficial in severe cases, especially when given early. 

M y practice is to use Tamiflu (or Relenza) for influenza cases irrespective of how long symptoms have occurred, especially in those at high risk of a severe course.

A Fever Without a Cause

Today one of my friends told me about a mother of one of her friends having an ongoing fever for 2 weeks. I immediately thought that this is likely not the result of an infectious disease, but of a malignancy of some sort.

What this person has is a fever of unknown origin (FUO). FUOs almost always require infectious disease consultation, represent a challenging aspect of infectious disease, and a problem I relish tackling. 

Usually an FUO is the result of an infection,  an autoimmune disease, or a malignancy. In those under the age of 65, infections make up the majority of cases. As one ages, however, infection becomes less likely as malignancy becomes more common. 

A fever is best understood as a warning sign and adaptation from the immune system that can be caused by a myriad of different processes. Nevertheless, they  prompt extensive work-ups in order to find the inciting cause, especially when present for two weeks.

Could Spock Have Been Infected With a Fungi?

Actor Leonard Nimoy, of Star Trek fame, recently announced that he has chronic obstructive pulmonary disease (COPD), a lung disease that comprises emphysema and chronic bronchitis. COPD is usually thought to be almost exclusively caused by smoking tobacco. 

While smoking is clearly a major etiologic factor responsible for the development of this condition, fascinating work--much of it done by Dr. Allison Morris at Pitt, has shown that a fungal infection may also play an important--and independent--role. This fungus, Pneumocystis jiroveci, usually headlines as the most common opportunistic infection that US HIV patients contract. However, this fungus also has the ability to colonize non-HIV infected individuals.

Colonization rates of this fungus are higher in COPD patients and the higher the colonization density, the more severe the COPD. 

Hypotheses regarding how this infection might be involved with COPD are centered on the inflammation its presence may trigger and the subsequent lung damage that occurs.

If COPD is indeed proved to be an infectious disease, it may translate into novel treatments that could decrease the considerable burden of this disease.

If There's A Raccoon in Your Bed, Call A Doctor

When I heard that a raccoon attacked a Massachusetts woman in her bed, I immediately assumed the raccoon to rabid--and it was. 

As a virus that infects the brain, rabies has the ability to change its host's behavior. As rabies is spread via saliva, it makes perfect sense, in evolutionary terms, for the virus to prompt some change in behavior in order to facilitate saliva exposure in potential new hosts. Hence, rabid animals "foam at the mouth" and become aggressive. See the book Rabid for a great history of the disease.

A raccoon's natural proclivity is to avoid human contact. For a raccoon, the most commonly reported wildlife reservoir for rabies in the US, to pounce into a bed and attack a woman is an unequivocal behavior change consistent with rabies. 

In the US, human deaths from rabies seldom occur given the ability of those exposed to access effective post-exposure prophylaxis which consists of the vaccine (thank you Louis Pasteur) and immune globulin. For those who develop symptoms, a fatal course is to be expected (unless the Milwaukee Protocol is initiated and is efficacious). 

Among the pantheon of infectious diseases, rabies has a special place in my heart as it was the children's book detailing Pasteur's work to develop the rabies vaccine that first captured my interest in the field.

Grave-robbers, No Need to Fear Smallpox

Since smallpox has been eradicated from the planet, thanks to DA Henderson, the human population has little to no immunity to this deadly pathogen. This fact is what prompts concern about its use as a bioweapon. 

In lectures, I often say that one case of smallpox represents a likely bioterror event. However, a recent paper published in Emerging Infectious Diseases details the ability of smallpox to persist in relics (corpses, scabs). 

The conclusion of this interesting paper is that historical relics do not pose a major threat of smallpox exposure as infectious viral particles have not been recovered from myriad samples, though viral DNA has been discovered. 

So grave-robbers are likely safe from this pathogen.