Today, I review, link to, and excerpt from The Cribsiders‘ #136: Vaccine-Preventable Illnesses – Measles, Mumps, Rubella, and Varicella: The Throwback Party Nobody Wanted.*

*Beneschott N, Ward BT, Dehority W, Berk J, Chiu C, Masur S. “#136: Vaccine-Preventable Illnesses – Measles, Mumps, Rubella, and Varicella: The Throwback Party Nobody Wanted”. The Cribsiders Pediatric Podcast. https:/www.thecribsiders.com/ March 19, 2025.

All that follows is from the above resource.

Summary:

Are you missing cases of measles, mumps, rubella, or varicella in your clinical practice without even knowing it? With declining vaccine rates, it is more important than ever to spot vaccine-preventable illnesses, diseases you may have only ever seen on board questions! Dr. Walter Dehority, a pediatric infectious disease physician at the Monroe Carell Jr. Children’s Hospital at Vanderbilt and an expert in vaccines, walks us through need-to-know pearls about the MMR-V suite, including how to spot measles before your colleagues do and which complications should make you think mumps, even without the stereotypical swelling.

Vaccine Preventable Illness Pearls

1. Vaccine-related disparities are a moving target, especially after COVID, and exist in a variety of populations including traditionally underserved racial and ethnic minorities and rural populations.
2. In measles, Koplik spots present about a day before the rash and can lead to an incredibly astute early diagnosis if noticed. From Koplik’s Spots from StatPearls. Prachi Jain; Manu Rathee. Last Update: May 1, 2023.
3. Rubella is not endemic to North America. If diagnosed in the United States, it is most likely imported.
4. Encephalitis due to mumps can occur in the absence of the classic parotitis.
5. While reliable in other infectious diseases, IgM testing is NOT reliable for varicella.
6. There is a specific varicella antibody product for post-exposure prophylaxis in  immunocompromised individuals who cannot receive the live varicella vaccine.

Vaccine Preventable Illness Notes

Background

• Declining Vaccination Rates
  • Vaccine hesitancy and disparities exist across different populations.
  • COVID-19 pandemic has affected vaccine uptake; trends continue to shift.
  • Example disparities:
    • Black women have higher cervical cancer rates, yet lower HPV vaccine uptake. (1)
    • American Indian/Alaska Native children have lower flu vaccine rates and higher flu-related hospitalizations. (2, 3)
• Barriers to Vaccination
  • Rural areas face challenges due to access and skepticism.
  • Community-based solutions:
    • Mobile vaccination clinics
    • Trusted local messengers
    • Non-traditional vaccine sites (e.g., schools, community centers)
• Approaching Vaccine Hesitancy
  • Contextualize discussion based on individual concerns
  • Avoid rigid scripts; engage in conversations
  • Address specific fears and misconceptions

Measles (Rubeola)

• Presentation (classically cough, coryza, and Koplik spots)
  • Non-exudative Conjunctivitis
  • Rash: Starts at the face → spreads downward (cephalocaudal). Resolves in reverse (head resolves last)
  • Koplik spots: Bluish-white lesions in the mouth, typically near molars
  • Cough and other respiratory symptoms
• Transmission
  • Highly contagious; airborne
  • By way of example, in 1991, an athlete on the field of the Minneapolis Metrodome had measles. Two unimmunized individuals sitting in the upper deck of a 60,000-seat stadium contracted the same strain (4).
  • Requires airborne precautions: N95 masks, negative pressure rooms
• Diagnosis
  • PCR (throat swab and blood), will turn positive around the time of the rash, more sensitive than IgM
  • IgM serology (useful after 3-7 days)
  • Paired IgG titers over time; fourfold rise is positive, though less helpful in the acute setting
• Complications:
  • Pre-vaccine era, about 1 in 1,000 fatality rates
  • Encephalitis is a well-described complication
  • Subacute sclerosing panencephalitis; a rare, but fatal post-measles degenerative neurologic illness
• Treatment
  • Primarily supportive care
  • Vitamin A: Reduces severity; recommended in hospitalized children. The mechanism of benefit is unclear
  • No strong recommendation for antiviral treatment such as ribavirin
• Post-Exposure Prophylaxis
  • Within 72 hours: MMR vaccine for immunocompetent unvaccinated individuals
    • One MMR has about 95% seroconversion, two shots 99% seroconversion
    • May vaccinate down to 6mo of age in outbreak settings
  • Within 6 days: Measles immunoglobulin (younger than 12 months old) or IVIG (older than 12 months old) for high-risk individuals (e.g., immunocompromised, pregnant people)

Rubella (German Measles)

• Presentation
  • Mild fever, rash, lymphadenopathy (posterior auricular, occipital)
• Differentiation from Measles
  • Much rarer than measles in the U.S. (all cases are imported)
  • Rash is less uniform than measles, spreads from head to toe but resolves in the same order (feet resolve last)
  • Rubella rash does not turn coppery (unlike Measles rash)
  • Less likely to have conjunctivitis or cough
  • No Koplik spots
  • Posterior auricular and occipital lymphadenopathy is Rubella specific
• Transmission and Diagnosis
  • PCR (nasopharyngeal or urine)
  • IgM serology (positive ~1 week after rash)
• Treatment
  • Supportive care; no specific antiviral or vitamin A recommendation.
• Post-Exposure Prophylaxis
  • No clear benefit from IVIG; vaccine prevents rubella

Differential Diagnosis: Viral illness such as adenovirus or EBV/mononucleosis, Kawasaki disease, leptospirosis, toxic shock syndrome.

Mumps

• Classic Presentation
  • Painful bilateral parotid gland swelling (90% of cases)
  • Prodrome: Fever, malaise, headache (1-2 days before swelling)
  • Orchitis (testicular inflammation) in ~25% of post-pubertal males
• Complications
  • CNS involvement (encephalitis, transverse myelitis)
  • Sensorineural hearing loss (1 in 1,000 cases)
  • Myocarditis, pancreatitis, glomerulonephritis
• Transmission
  • Highly transmissible, less transmissible than measles
  • Still endemic in the United States
  • Transmitted by airborne and respiratory droplets.
  • Can spread easily in college dorms due to waning immunity
• Diagnosis
  • PCR from buccal mucosa (best from Stensen’s duct), best at the time of parotitis.
  • IgM serology (useful after ~7 days)
  • CSF PCR for encephalitis cases
• Treatment
  • Supportive care (hydration, pain management)
  • No role for antivirals
• Post-Exposure Prophylaxis
  • During outbreaks, a third MMR dose can be given.
  • Mumps vaccine effectiveness declines over time (waning immunity in young adults).

Fun story: the current MMR still uses the Jerell Lynn strain, named for the daughter of the Mumps vaccine researcher Dr. Maurice Hilleman. Dr. Hilleman isolated the strain from his daughter when she contracted mumps in 1963. The mumps vaccine is  the second fastest vaccine developed behind the COVID-19 vaccines.

Varicella (Chickenpox)

• Classic Presentation
  • Prodrome: Fever, malaise (~1 day before rash)
  • Rash Pattern:
    • Starts centrally (face, trunk) → spreads outward towards extremities
    • Lesions in various stages: macules, papules, vesicles, crusted scabs
    • “Dew drop on a rose petal” appearance (vesicles on erythematous base).
  • Highly pruritic (itchy) as well as painful
  • Respiratory disease, cough (often overlooked)
• Breakthrough Varicella
  • Vaccinated individuals may develop a milder form (<50 lesions)
  • May have small amount of lesions after vaccinations
  • Not highly contagious.
• Transmission
  • Airborne and direct contact.
• Diagnosis
  • PCR of a freshly unroofed lesion (best test)
  • Serology:
    • IgG can confirm past infection
    • IgM not very reliable
  • Depending on clinician comfort, may be diagnosed by exam alone (but this is maybe old-school)
  • May also swab for herpes or coxsackievirus
• Treatment
  • Supportive care: Antipyretics, oatmeal baths, antihistamines.
  • Acyclovir/Valacyclovir is indicated for higher-risk group such as Immunocompromised, unvaccinated older children (>12 years), or children with eczema or underlying skin conditions. It is not routinely needed for healthy young children.
• Post-Exposure Prophylaxis
  • Varicella vaccine (within 3-5 days) for immunocompetent individuals.
  • Varizig (Varicella immune globulin) for immunocompromised individuals.
  • Acyclovir prophylaxis (if vaccine or Varizig not possible) should be delayed until day 7 post-exposure (targets second viremia phase).
• Shingles (Zoster) Considerations
  • Varicella vaccination reduces wild-type VZV boosting in adults.
  • Some studies suggest standard vaccination may increase early shingles cases in adults
  • Zoster can occur after vaccination, but usually mild.

Take Home Points

• Keep vaccine-preventable illnesses in the back of your mind, especially in unimmunized or under immunized patients.
• You don’t have to remember everything, but keep a few high-yield pearls or red-flags that cue you in. Here are a few examples but make them your own!
  • Measles: non-exudative conjunctivitis
  • Rubella: posterior auricular and occipital adenopathy
  • Mumps: encephalitis can occur without parotitis
• Children’s Hospital of Philadelphia has great vaccine resources, especially for families!

Citations

1. Arvizo C, Mahdi H. Disparities in cervical cancer in African American women: What primary care physicians can do. Cleve Clin J Med. 2017 Oct;84(10):788-794. doi: 10.3949/ccjm.84a.15115. PMID: 28985174.
2. Brewer, L.I., Ommerborn, M.J., Nguyen, A.L. et al. Structural inequities in seasonal influenza vaccination rates. BMC Public Health 21, 1166 (2021). https://doi.org/10.1186/s12889-021-11179-9
3. Prabhu P. Gounder, Laura S. Callinan, Robert C. Holman, Po-Yung Cheng, Michael G. Bruce, John T. Redd, Claudia A. Steiner, Joseph Bresee, Thomas W. Hennessy, Influenza Hospitalizations Among American Indian/Alaska Native People and in the United States General Population, Open Forum Infectious Diseases, Volume 1, Issue 1, Spring 2014, ofu031, https://doi.org/10.1093/ofid/ofu031
4. Ehresmann KR, Hedberg CW, Grimm MB, Norton CA, MacDonald KL, Osterholm MT. An outbreak of measles at an international sporting event with airborne transmission in a domed stadium. J Infect Dis. 1995 Mar;171(3):679-83. doi: 10.1093/infdis/171.3.679. PMID: 7876616.

 

Links

CHOP Vaccine Education Center HERE

While not mentioned often in the episode, the RedBook is the infectious disease handbook of the AAP and can be found HERE.