In case you have been in a news and media blackout recently, Measles is back. I have seen headlines such as “Measles cases rocket toward record level”, “555 Measles cases spread to 20 states,” and “Measles outbreak hits ‘completely avoidable’ 25-year high”…despite being declared eliminated in the United States in 2000. If you are still in current practice, odds are that none of us have seen measles in front of us or thought that we had pretty much eliminated it. Personally, I have only seen one case a few years back and it was in an un-immunized child of a migrant farm worker. To be honest, it could have been very easily overlooked as just another “viral illness” or “viral exanthem”. Sometimes, it pays to be lucky rather than good. The purpose of this blog is to help prepare you in case this walks into your practice setting…making you both lucky and good.
Why do we care?
Measles is a viral illness. We send home hundreds if not thousands of patients with viral illnesses every month. According to the WHO, measles is one of the most infectious diseases known to mankind. Additionally, approximately 330 people worldwide die from measles daily. Most of these are children under 5. The disease is preventable with immunizations. I won’t use this space to get on my soapbox about staying current with immunizations. Suffice it to say, that in this case I feel that one person’s decision to not to get immunized can adversely effect the health of others.
As a medical provider, you will also be responsible for answering questions from patients. Think back a couple of years ago when Zika was all over the news. Immediately, I was having to hit the CDC, WHO, and health department websites to learn what I could about a viral illness I had never studied or heard of in school. Why? My patients were asking questions and I hated not having good answers. The same thing is happening again with measles. Last week, I had a mother bring in her afebrile teenage son. She was “pretty sure” that the scattered papular rash on the lower legs and arms were insect bites. After the discussion of using bug spray and topical anti-histamines, the real reason for the visit popped up. She told me that she just wanted to be sure that this wasn’t a measles rash. I can’t be the only person experiencing an uptick in measles paranoia and you can probably expect them too. Are you ready for it and are you able to answer patient questions?
MEASLES: a primer
The first thing that I think of with measles is what I learned in school: the 3C’s. Cough, Coryza, and Conjunctivitis. I didn’t even know what coryza was! According to Stedman’s Medical Dictionary, coryza is acute rhinitis. I prefer to think of it as cold/URI symptoms like runny nose and sneezing. Those 3Cs alone could send be any of the viral illnesses we send home on a daily basis. Anything from the flu to a basic allergy flare-up could fall in that broad general description.
The most important diagnostic tool you have is your history and physical exam!! One of your first questions should be about immunization status. While not entirely able to help you rule in/out measles, it could help you breathe a little easier. According to current CDC guidelines, the first measles vaccination is recommended between 12-15 months and the second immunization is recommended at 4-6 years. As you can see, there is a large window for new infants to be un-immunized. Unfortunately, this age group is hardest hit by the complications of measles such as pneumonia and encephalitis. Effects of measles on the infant age group are devastating and usually result in death. The second question should be about possible exposures…unvaccinated exposures, recent travel, etc. The biggest aid to diagnosing measles is to keep it in your differential diagnosis. I’ll admit that this is sometimes hard to do after the 20th URI diagnosis during cold and flu season. But immunization status should be a big red flag for you to stop and pause.
The CDC offers a pretty good description of measles progression which when correlated with your physical exam findings follows a fairly typical disease progression and recognizable clinical features. Initially, there is an 8-12 day incubation period following the initial exposure. Then the prodromal symptoms begin…the 3Cs. Cough, coryza, and conjunctivitis. During this phase, you may see Koplik spots (again, key-word medicine and board question fodder). Koplik spots are blue-white lesions on an erythematous base on the inner buccal mucosa. If they are present, they are typically located across from the molars. Here’s the kicker…Koplik spots are not always present. However, if they are present, they are virtually pathognomonic for measles and you have your diagnosis.
After 2-4 days of the prodromal symptoms, 2 important symptoms develop. The first is a fever. Typically, 103-104F is the norm and these patients look sick. This is typically what brings them in to your practice setting. Occasionally, they develop photophobia with the fever. The second development is a maculopapular rash. If you have studied rashes of pediatric illness you probably remember there are distinct patterns or presentations to differentiate between them (think…herald patch, reverse Christmas Tree pattern, “Slapped Cheek” appearance, and dew-drops on rose petals). For the measles rash, it will often start on the forehead near the hairline. Over the next 3 days, the rash spreads downward to the trunk and then the extremities. Often times, the papules will coalesce into macules that cover a large surface area. Then the rash will begin to fade in the same pattern that it appeared. The fever will peak after about 2-3 days after the rash begins. Patients are considered contagious from 4 days before the rash until 4 days after the rash.
Ok, you made your diagnosis, now what?
These patients are quarantined and admitted. They are highly infectious and usually very sick. Transmission of the viral respiratory illness is through droplets. There are various immunoassays and serology testing that can be used to confirm diagnosis but the turnaround time is 2-3 days and you need to act long before that. There is no specific anti-viral care for measles. Measles care is primarily supportive and aimed at treating any secondary bacterial infections that develop.
Hopefully, after a this quick primer on measles you’ll feel a bit more confident answering questions and identifying the condition should it walk into your practice. I have included a link to the CDC’s information of “measles for healthcare professionals” which also includes a small section in possible post-exposure prophylaxis. Additionally, we have included some photos of Koplik spots and measles rash to help build your clinical acumen.