Measles, also referred to as rubeola, is a viral illness that is easily transmissible via the air. In previous decades, measles was a common childhood illness; however, vaccination has drastically reduced infection rates and even led to its eradication in the 2000s.

Unfortunately, amid declining vaccination rates and growing vaccine hesitancy in the US, measles cases have substantially increased. According to Centers for Disease Control and Prevention (CDC) data, in 2025, there were 2,289 confirmed measles cases in the US, while as of August 6, 2026, there are already 2,465 confirmed measles cases. These numbers point to how, after 25 years of largely eradicating the disease, the US is experiencing the largest measles outbreak in 35 years.

With measles outbreaks becoming more common and leading more patients to seek medical care, it’s important for healthcare professionals to identify potential measles cases promptly. Measles is a highly contagious disease, and ER nurses should spot possible measles cases even before the telltale rashes appear on the body to isolate potential measles patients and reduce disease transmissibility. Doing so can help keep immunocompromised and vulnerable patients from being exposed and provide timely treatment to those with measles.

This article provides early measles symptoms that ER nurses must know to prevent further measles outbreaks in 2026.

The Prodrome Phase: Fever, Cough, Coryza, and Conjunctivitis

The incubation period for measles is typically 11 to 12 days from first exposure to the virus. The prodromal symptoms, the earliest symptoms, appear afterward and last for about two to four days. For measles, the following are the most common prodromal symptoms to watch for in patients:

Measles Prodrome 3Cs: Fever, Cough, Conjunctivitis, and Coryza

• Fever: Gradually increasing and potentially peaking as high as 103°F to 105°F
• Cough: A dry, persistent cough that sounds barky
• Coryza: Nasal congestion, runny nose, and copious clear mucus
• Conjunctivitis: Red, watery, and bloodshot eyes

Koplik Spots: The Oral Sign That Confirms Measles Before the Rash

Right after the prodromal phase, another hallmark symptom appears: Koplik spots. Koplik spots, which appear a day before rashes, are slightly raised bluish-white spots found in the buccal mucosa or, more atypically, the soft palate and conjunctival fold. Koplik spots often appear like grains of salt with a reddish background.

They can be found in 60 to 70% of those with a measles infection and typically stay for two or three days.

Rashes: The Telltale Measles Symptom

Measles rashes typically start on an infected person’s head and gradually spread to the neck, body, arms, legs, feet, and toes. The rashes appear with both flat and bumpy or raised components (maculopapular) and can join together as they spread throughout the body. The rashes are not usually itchy, but they oftentimes feel warm to the touch.

Triage Questions to Ask Before a Patient Enters the Waiting Room

Because measles rashes appear days before the prodromal phase, when the disease is at its most contagious, nurses must screen patients properly to prevent measles from spreading, especially to high-risk patients.

The following are some helpful measles triage screening questions that nurses with presumptive measles immunity can ask at the ER door:

• Do you have a fever?
• Do you have a runny nose or nasal congestion?
• Do you have a cough? If yes, when did it start?
• Have you developed a rash?
• Have you been previously informed by your doctor or a healthcare professional that you have a weakened immune system?
• Have you received two doses of the measles vaccine (MMR)?
• Are you accompanied by a friend or a family member?
• Is there a measles outbreak in your community? Have you been exposed to anyone who’s had measles recently?
• Have you been out of the country 21 days before the symptoms started?

Patients who are suspected to have measles (2 years and older) and their companions should be given face masks and placed in an airborne infection isolation room (AIIR) or an enclosed private room. Healthcare professionals assisting patients with suspected measles infection should wear the necessary PPE and perform proper handwashing before and after assisting patients.

Proper and timely questioning about patients’ symptoms, exposure history, vaccination status, and recent travel can help identify suspected measles cases early and ensure prompt isolation and referral. Early recognition and reporting prove to be effective in limiting transmission, protecting vulnerable people, and helping keep infection rates low throughout the community.