Nav: Home

Mumps study shows immunity gaps among vaccinated people

September 02, 2019

Immunity against mumps virus appears insufficient in a fraction of college-aged people who were vaccinated in childhood, research from Emory Vaccine Center and the Centers for Disease Control and Prevention indicates. The findings highlight the need to better understand the immune response to mumps and mumps vaccines.

The results of the study are scheduled for publication in PNAS.

In the last 15 years, several mumps outbreaks have occurred among college students, sports teams and in close-knit communities across the United States. Two possible contributing factors include waning vaccine-induced immunity and differences between the strain of mumps virus now circulating and the vaccine strain, which is part of the standard measles, mumps, and rubella (MMR) childhood vaccine.

"Overall, the MMR vaccine has been great, with a 99 percent reduction in measles, mumps and rubella disease and a significant reduction in associated complications since its introduction," says Sri Edupuganti, MD, MPH, associate professor of medicine (infectious diseases) at Emory University School of Medicine and medical director of the Hope Clinic of Emory Vaccine Center. "What we're seeing now with these mumps outbreaks is a combination of two things - a few people were not making a strong immune response to begin with, and the circulating strain has drifted away from the strain that is in the vaccine."

Emory and CDC scientists collaborated on a study that included 71 people, aged 18 to 23, in the Atlanta area - the largest study so far of mumps memory B cells in vaccinated people. Recruitment of participants took place in 2010. Although almost all (69/71) had received two MMR doses, 80 percent of the participants received their second MMR more than ten years before enrolling in the study.

Most participants (93 percent) had antibodies against mumps, but ten percent of people in the study had no detectable mumps-specific memory B cells, which would normally be capable of producing antiviral antibodies as part of a memory response after exposure to mumps virus. On average, the frequency of memory B cells in participants' blood was 5 to 10 times lower for cells making antibodies against mumps, compared with cells making antibodies to measles or rubella.

In addition, antibodies from the participants did not neutralize wild-type mumps virus as efficiently as the vaccine virus. At least six study participants may have been potentially susceptible to infection with the currently circulating wild-type mumps strain, the paper concludes. The researchers did not see a clear relationship between the timing of vaccination and low antibody or memory B cell levels.

Other research has shown that a third MMR dose resulted in increased neutralizing antibody responses to mumps in some individuals with low neutralization titers; however, the antibody levels declined toward baseline by 1 year so the effect was not long-lasting. In 2017, the CDC's Advisory Committee on Immunization Practices approved a third dose of MMR vaccine for groups of people who are at risk because of an ongoing mumps outbreak.

The Jeryl Lynn mumps vaccine strain in the MMR vaccine was originally cultured from a scientist's daughter's throat in the 1960s. Though there is only one serotype of mumps virus, the current circulating strain ("genotype G") is genetically distinct from the vaccine strain. How these genetic changes affect the antigenic properties of the wild-type strain is not fully understood.

Additional studies to characterize the immune response to wild-type and vaccine strains of mumps are clearly needed to determine if developing a new mumps vaccine is warranted. Developing a new mumps vaccine would take a large investment in clinical trials needed to demonstrate safety and efficacy.

Symptoms of mumps include those common to viral illnesses - fatigue, body aches, headache - but a distinctive aspect is often swelling of the salivary glands. More severe cases can lead to encephalitis or deafness. The disease is spread by direct contact, droplets, or contaminated objects. It usually takes 16 to 18 days for mumps symptoms to show up after infection starts.
-end-
The first author of the paper is Ata Ur Rasheed Mohammed, PhD, previously a research associate at Emory and now at the CDC. Co-authors at Emory include Walter Orenstein, MD and Rafi Ahmed, PhD, and at the CDC, Carole Hickman, PhD, mumps team lead in the Division of Viral Diseases. Ahmed is a Georgia Research Alliance Eminent Scholar.

Emory University received a research grant through the Investigator Initiated Studies Program of Merck and Co., Inc. The study was also supported through the Cooperative Center on Human Immunology of the Emory Vaccine Center (National Institute of Allergy and Infectious Diseases U19AI057266).

Emory Health Sciences

Related Immune Response Articles:

How to boost immune response to vaccines in older people
Identifying interventions that improve vaccine efficacy in older persons is vital to deliver healthy ageing for an ageing population.
Unveiling how lymph nodes regulate immune response
The Hippo pathway keeps lymph nodes' development healthy. If impaired, lymph nodes become full of fat cells or fibrosis develops.
Early immune response may improve cancer immunotherapies
Researchers report a new mechanism for detecting foreign material during early immune responses.
Researchers decode the immune response to Ebola vaccine
The vaccine rVSV-EBOV is currently used in the fight against Ebola virus.
Immune response depends on mathematics of narrow escapes
The way immune cells pick friends from foes can be described by a classic maths puzzle known as the 'narrow escape problem'.
Signature of an ineffective immune response to cancer revealed
Our immune system is programmed to destroy cancer cells. Sometimes it has trouble slowing disease progression because it doesn't act quickly or strongly enough.
Putting the break on our immune system's response
Researchers have discovered how a tiny molecule known as miR-132 acts as a 'handbrake' on our immune system -- helping us fight infection.
Having stressed out ancestors improves immune response to stress
Having ancestors who were frequently exposed to stressors can improve one's own immune response to stressors, according to Penn State researchers.
Researchers discovered new immune response regulators
The research groups of Academy Professor Riitta Lahesmaa and Research Director Laura Elo from Turku Centre for Biotechnology have discovered new proteins that regulate T cells in the human immune system.
Blueprint for plant immune response found
Washington State University researchers have discovered the way plants respond to disease-causing organisms, and how they protect themselves, leading the way to potential breakthroughs in breeding resistance to diseases or pests.
More Immune Response News and Immune Response Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Climate Mindset
In the past few months, human beings have come together to fight a global threat. This hour, TED speakers explore how our response can be the catalyst to fight another global crisis: climate change. Guests include political strategist Tom Rivett-Carnac, diplomat Christiana Figueres, climate justice activist Xiye Bastida, and writer, illustrator, and artist Oliver Jeffers.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Speedy Beet
There are few musical moments more well-worn than the first four notes of Beethoven's Fifth Symphony. But in this short, we find out that Beethoven might have made a last-ditch effort to keep his music from ever feeling familiar, to keep pushing his listeners to a kind of psychological limit. Big thanks to our Brooklyn Philharmonic musicians: Deborah Buck and Suzy Perelman on violin, Arash Amini on cello, and Ah Ling Neu on viola. And check out The First Four Notes, Matthew Guerrieri's book on Beethoven's Fifth. Support Radiolab today at Radiolab.org/donate.