Petechial rash caused by Rocky Mountain Spotted Fever

Petechial rash on my ankle caused by RMSF (2004)

More than 3 years ago I shared a personal story where I  describe my experience with Rocky Mountain Spotted Fever or RMSF – a condition caused by Rickettsia rickettsii, a species of bacteria that is spread via tick bites. That blog post has become the most commented (178 so far) where people share with the world their horrifying accounts of RMSF.

There is a tool by Google – “Insights for Search” (still beta) that shows web search interest for a given search term(s) over a period of time. The results can be  filtered based on a geographical location, and general search categories. Google also offers an option to forecast the search trend for your query about one year into the future.

I examined the search phrase “rocky mountain spotted fever” in the US from 2004 to present. Here is the graph (click to enlarge):

Rocky Mountain Spotted Fever Trends

Rocky Mountain Spotted Fever Search Trends (2004-2010)

As you can see, every year there is a significant spike in the number of searches around June; however, year after year that peak is becoming shorter and shorter, forming a steadily descending trend line.

What does this year over year decline imply? You could say if fewer people get sick, than less googling for “rocky mountain spotted fever” will be done, right? Well, I don’t think it is that simple. Google reliably shows that the interest is declining; however, you can still have a decline in interest while the number of people who get sick with RMSF holds steady or even increase. The explanation could be very simple – RMSF is easily misdiagnosed. When a doctor is presented with the initial onset of  symptoms such as high fever, muscle ache, headache, petechial rash and etc., I really doubt that Rocky Mountain Spotted Fever will even make the top 10 on the list.

The Center for Decease Control and Prevention (CDC) only shows the number of reported cases through 2002:RMSF CDC

But as you can see there is a sharp increase in the number RMSF cases from 1997 to 2002, I seriously doubt that trend stopped, but I could be wrong.