Who Started the Disneyland Measles Outbreak?

By Tetyana Obukhanych, Ph.D.

It is well known that not everyone infected with the measles virus will exhibit classical measles with a telltale 7-day rash.  There is a type of measles called modified measles (or measles without rash), which happens when the measles virus infects a previously vaccinated individual, whose protective titers are still high enough to prevent the rash but not high enough to prevent a respiratory infection, resulting in generalized sickness that may look and feel like the flu.  One may not be able to tell it apart from the flu, unless a laboratory confirmation on the virus is done.  But who would be testing their flu for the measles virus, unless they have a good reason to do so?
 
While modified measles in itself is not considered important enough to be a reportable disease (hence cases of modified measles do not contribute to measles stats), is this type of measles contagious?  If it is, then a person with modified measles might be spreading the measles virus, unbeknown to themselves and authorities. 
 
The only sure way to tell if modified measles is contagious or not is to re-create it under controlled laboratory conditions in experimental animals (e.g. macaques can be infected with the measles virus), then house them together with other susceptible animals and monitor virus transmission.  To my knowledge, such experiment has not been done.  Attempts to track transmissibility of the measles virus from a significant number of modified measles cases in humans in unpredictable epidemiological settings are likely to be cost-prohibitive and come up empty-handed. 
 
However, one could make a peculiar theoretical prediction about an outbreak started by a modified measles case, if it were contagious.  The prediction is that such an outbreak would lack an identifiable index case.  Because by the time a bunch of susceptible contacts would have developed their measles (typically 2 weeks later due to the virus incubation period), it would be too late to search for their common contact who might have had something that looked like the flu, as far as they could tell, but was in fact a case of modified measles and the original source of measles exposure.
 
Was there at any time in recent history a measles outbreak where the index case could not be identified? 

The 2015 California Disneyland measles outbreak.  Bingo.
 
If I remember correctly, the official story about the absence of an identifiable index case was that the person who started the outbreak was a foreign visitor to Disneyland, who managed to leave the country before public health officials could figure out who he or she was.  This scenario comes very close to being implausible, given that according to the CDC, measles may be transmitted from 4 days before to 4 days after rash onset. In addition, fever and flu-like respiratory symptoms typically precede the rash by 2-4 days (the prodrome), thus leaving merely 0 to 2 days for a window of transmissibility without symptoms.  

In other words, in a span of zero to two days, a mysterious visitor went to Disneyland, then right away got to the airport and onto the international flight back to their home country, all before fever and cough made them noticeably sick and possibly apprehended and tested for some deadly disease during international travel.  Not to mention that the mysterious visitor apparently infected many people in Disneyland, but no one on the international flight right after the Disneyland visit, thus remaining untraceable.  I sure hope I am missing some important detail here that could make the tale of a measly foreign visitor to Disneyland more real.  Because I do want to believe our trusty authorities. 
 
Or could the index case have simply been a contagious case of modified measles, who never left the country after visiting Disneyland and who was never suspected to have had measles infection because it didn't produce rash?
 
We cannot see black holes, but we can deduce about their existence from how visible matter behaves in their vicinity.  Clinical measles is ‘visible’ to public health, whereas modified measles is not.  But we can similarly deduce about the existence of a contagious modified measles case from a pattern of an outbreak that happens without an apparent index case, especially when the official explanation was a bit of a stretch.  
 
Moving forward, public health officials will have to stop ignoring modified measles in vaccinated individuals, which may be posing a bigger 'threat' than vaccine hesitancy to the eradication of the measles virus.  But eventually, humanity will wise up and stop unproductive and protracted attempts at measles eradication altogether and will instead re-focus on the immune system to turn measles into a perfectly survivable disease all around the world. 

But do not wait for authorities to tell you how to build up your immune system.  Watch the NIF class so that you can do it yourself.