Health awareness

Finding joy after surviving cervical cancer twice

How one woman embraced life, marriage and motherhood despite her cervical cancer diagnosis

September 25, 2025

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Chrstine Granado and her family

Several years ago, Christine Granado was living happily in New Jersey with her fiancé and then-9-year-old son, but she felt something wasn’t right.

In the span of a year, she lost three pregnancies. The first miscarriage came as a total shock. With the second, she felt confused. After the third, she was afraid something was terribly wrong. She decided to go for a routine checkup. While undergoing a series of tests ordered by her OB-GYN, she got surprising news: she was diagnosed with stage IIB squamous cell cervical cancer that had spread to her lymph nodes. At just 28, Christine said she felt disbelief.

“How can I have cancer at this age?” she asked herself. “I remember peeking through my bangs, feeling like I was trying to hide behind them.”

Young women are at risk for cervical cancer, too

Granado wasn’t alone in asking herself that question. Cervical cancer is most often diagnosed between the ages of 35 and 44. In 2022, over 660,000 people around the world were diagnosed with cervical cancer. In 2025, it’s estimated that around 13,000 people will be diagnosed with cervical cancer in the U.S.

Regular screenings can catch early changes in the cervix before they turn into cancer, but not everyone has the same access or risk factors for cervical cancer. That’s why it’s so important to make sure everyone gets the care they need.

Beginning her cancer treatment journey

Granado started treatment as soon as possible. She was prepared for physical side effects but was overwhelmed by the other changes that soon followed, including how she felt about losing her fertility. She and her partner discussed preserving her eggs but decided against it as doing so would have delayed her treatment.

Granado’s cancer went into remission for three years, and she found joy again: She and her fiancé got married and decided to have a baby via surrogate.

The shock of a recurring cancer diagnosis

Then, soon before her son was born, Granado started having unexplained chest pains. A CT scan found enlarged lymph nodes. She was diagnosed with metastatic cancer.

“When I got the recurrence diagnosis, I was devastated. It was hard to hear, but it motivated me to finish things, to contact a lawyer and get things in my kids’ names — to think about life after me,” she said. 

It also motivated her to continue with more treatments. During her second round of treatment, Granado was able to welcome her new son. When she saw him, she took him in her arms: “I bawled my eyes out.” 

A focus on mental health 

In addition to her son’s arrival, Granado said a focus on herself has sharpened her resolve to live her best life. When the cancer came back, she grieved for her life. She would cry and sleep all day. Her depression stopped her from enjoying precious time with her family.

“The most disabling thing I dealt with was the depression,” she said. “There were days when I would feel physically OK, but I’d still stay in bed all day.” Thankfully, Granado had the support of a psychologist and a psychiatrist who helped her feel well again. 

little boy laying with a dog

Cervical cancer won’t stop her from living her best life 

Granado has been able to complete a master’s degree in health leadership, and her family has a new border collie named Harry. Even everyday activities like going to the hardware store and winding down with a book mean so much more now. She appreciates the small details, like watching TV with her son on the couch.

“Life has been amazingly boring,” she says. “In a good way.” 

Granado said she hopes her story will inspire others and give them hope in the face of a cancer diagnosis.

Innovation

Macrocyclic peptides: a new research frontier

Merck scientists are exploring macrocyclic peptides, a new way to combine the properties of a biologic in a pill.

September 15, 2025

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Macrocyclic peptides

Small molecules, generally taken as pills, make up nearly 90% of medicines used today. It’s hard to think of a world without them. The use of small molecules has been critical in expanding the reach of and access to medicines around the world.

But it’s challenging for small molecules to impact the large featureless surfaces of protein-protein interactions, which govern a wide range of biological processes in our bodies.

Chris Plummer, Senior Director, Discovery Chemistry, Merck

To target these interactions, scientists have turned to large molecule biologic therapies, like monoclonal antibodies, which — taken by infusion or injection — have been critical in advancing the treatment of many diseases, including some cancers and autoimmune disorders.

Over a decade ago, Merck scientists began investigating a way to create a new kind of medicine that would combine the potency and precise targeting of an antibody with the stability and ease of administration of a small molecule or pill.

“Macrocyclic peptides allow us to cast a wider net on the protein interactions we want to drug, providing a vast and untapped opportunity to access a wider range of targets and potentially new ways to treat different diseases,” said Dani Schultz, director of chemistry.

An intermediate-sized modality: not too big, not too small

Macrocyclic peptides, with their intermediate size — not too big, not too small — combine the properties of both small molecules and biologics. With their larger size and unique ring shape, macrocyclic peptides can tightly bind ample surface area to disrupt protein-protein interactions compared to traditional, linear-shaped peptide therapies. 

Size differences between small molecule, peptide and antibody

“The design and invention of macrocyclic peptides is notoriously complicated,” said David Thaisrivongs, director of chemistry.

David Thaisrivongs

“Similarly, scaling production up for a macrocyclic peptide small molecule, with four to five times the size and complexity of a typical small molecule, represented a bold endeavor.”

  • David Thaisrivongs
    Director of chemistry, Merck

For our researchers, this work started by screening large libraries of cyclic peptides using messenger RNA display technology. This led to the identification of cyclic peptide leads that were optimized using 3-dimensional protein structure-based design and advanced computational techniques. Further molecular iterations and refinements improved the absorption, potency and stability of the first candidate.

“A diverse, interdisciplinary team of skilled and determined people from across our chemistry organization has dedicated substantial efforts to advancing this science,” said Thaisrivongs.

Macrocyclic peptides potentially open new possibilities in drug discovery 

Our ongoing macrocyclic peptide discovery efforts represent a new era in drug discovery which may one day allow us to treat diseases that have long evaded traditional small molecule approaches and help improve access to medicines typically administered via injection or intravenously. 

“Macrocyclic peptides are a new modality, and we’re still in the early stages of understanding their potential to impact disease and patient care,” said Schultz.

“There’s no playbook here, we’re innovating and developing new techniques on how to optimize and synthesize macrocyclic peptides — it’s really thrilling for me as a scientist because the potential is huge.”

  • Dani Schultz
    Director of chemistry, Merck
Dani Schultz

Health awareness

Helping protect against vaccine-preventable diseases

Vaccination is one of the many ways you can help protect your loved ones against certain vaccine-preventable diseases

September 10, 2025

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Vaccines are one of the greatest public health success stories in history

Vaccines help protect against more than 30 potentially life-threatening diseases and are one of the greatest public health achievements of our time.

We recognize and support many global health stakeholders for their efforts in raising awareness about the importance of vaccination and helping prevent infectious diseases around the world.

Broader vaccination coverage along with other public health measures have contributed to the eradication of smallpox and significantly decreased the incidence of other vaccine-preventable diseases.

Declining immunization rates persist

Childhood immunization rates have been declining in recent years, with the global population facing the largest sustained decline in approximately 30 years.

mother laying down in bed with her newborn

A downward trend in global immunization persists, with immunization coverage stalling in 2023, leaving 2.7 million more children un- or under-vaccinated compared to 2019.

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Research shows that routine childhood vaccinations for people in the U.S. born from 1994-2023 have contributed to helping prevent about 508 million illnesses and 32 million hospitalizations.

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In 2024, it’s estimated that more than 14.3 million infants around the world did not receive some routinely recommended vaccines.

Recovering immunization rates together

Now, more than ever, we have an opportunity to reimagine the role we all can play.

At Merck, our broad portfolio of vaccines helps protect against certain infectious diseases affecting individuals around the world and across all stages of life from infancy through older adulthood. Through our work in vaccines, we’re committed to helping protect people from vaccine-preventable diseases today and for generations to come.

But we can’t be successful alone. That’s why we’re working with a variety of stakeholders to help increase vaccination rates, build trust and enable access to vaccination services for everyone who can benefit from them.

We’re also encouraging individuals to speak with their health care providers about vaccines that may be recommended for them or their families.

Woman smiling outstretching her arms to hug a young girl

Merck and its legacy companies have a 100+ year history of innovation and commitment to helping prevent disease by discovering, developing, supplying and delivering vaccines.

To keep pace with the ever-evolving disease landscape, we go where the need is to find new ways to address complex public health problems. We continue to invest in groundbreaking research and breakthrough technologies to help protect against potentially life-altering vaccine-preventable diseases.

Sustainability

Merck publishes Purpose for Progress Impact Report 2024/2025

August 18, 2025

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Our company’s purpose is to use the power of leading-edge science to save and improve lives around the world. This purpose serves as our compass and guides us every day. Our Purpose for Progress: Merck 2024/2025 Impact Report provides a comprehensive view of how we’re pursuing innovative science for the health of people and animals and ensuring our efforts drive significant and sustainable value.

“Our long-standing commitment and focus on advancing access to health, operating responsibly and implementing strategies that protect the health of people, animals and the planet is unwavering,” said Rob Davis, chairman and CEO. “As we continue to navigate the rapid pace of change happening all around us, I am proud of the progress we’ve made thus far, and I remain optimistic about our future.”

A few highlights from this year’s report*

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>247M

People enabled access to our innovative medicines and vaccines through access solutions.

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>66M

People reached with our social investments in low- and middle-income countries and in underserved populations in high-income countries. We've surpassed the goal of reaching 50 million by 2025.

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92%

Countries reached globally with our products, surpassing our goal for the fourth year in a row.

*All numbers as of 2024 (report page 15)

Our employees worldwide played a pivotal role in delivering novel solutions that addressed some of the world’s most serious and complex global health challenges. We’re proud that in 2024, our medicines and vaccines reached more than 450 million people around the world.

Our sustainability strategy has four main areas of focus

  • Access to health: In collaboration with global health stakeholders, our social investments aim to advance access to quality health systems, and we seek to ensure that our products are accessible and affordable worldwide.
  • Employees: We recognize that our ability to excel depends on the integrity, knowledge, imagination, skill, diversity of thought, perspectives and experiences, and well-being of our employees.
  • Environmental sustainability: We strive to operate our business sustainably, considering the impact on both the health of our planet and its inhabitants, while also providing opportunities for product innovation and reduction in costs and risks. We have a long history of environmental stewardship and compliance, and we continuously evolve our strategy and efforts in the face of a changing climate.
  • Ethics and values: Our ethics and values are at the center of everything we do. Through our unwavering commitment to transparency, we are committed to earning the trust and confidence of our stakeholders.

Learn more about our progress in these areas and read this year’s report.

Innovation

Our Q2 2025 financial results

July 29, 2025

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Merck’s (NYSE: MRK) Q2 2025 sales performance reflects strength across oncology and animal health, as well as increasing contributions from new launches. Our company announced Q2 worldwide sales of $15.8 billion.​

​”Earlier this month, we were pleased to announce our pending acquisition of Verona Pharma, which augments our portfolio and pipeline and is another example of acting decisively when science and value align,” said Rob Davis, chairman and CEO. “Today, we announced a multiyear optimization initiative that will redirect investment and resources from more mature areas of our business to our burgeoning array of new growth drivers, further enable the transformation of our portfolio, and drive our next chapter of productive, innovation-driven growth. With these actions, I am confident that we are well positioned to generate near- and long-term value for our shareholders and, most importantly, deliver for our patients.”​

​Merck anticipates full-year 2025 worldwide sales to be between $64.3 billion and $65.3 billion.​

​Take a look at the infographic below for more details on Q2 2025 results.

2025 Q2 Financial result

Download infographic

Innovation

Exploring KRAS: A precision approach in oncology

Merck scientists research oncogene mutations driving cancer growth

July 18, 2025

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3D depiction of KRAS protein complex
3D depiction of KRAS protein complex

How oncogenes like KRAS drive cancer growth

Armed with an ever-deepening understanding of cancer biology and advanced precision medicine tools, scientists have traced the molecular basis of cancer cell formation and tumor growth to alterations in key genes, known as oncogenes. Oncogenes play a crucial role in driving cancer growth by disrupting normal cellular processes that control cell growth and division.

When oncogenes are mutated, they cause cells to grow and divide uncontrollably, leading to tumor formation and cancer development. Understanding how oncogenes drive cancer development provides a potential means to explore new research approaches aimed at the specific genetic drivers of a patient’s cancer compared with a one-size-fits-all approach.

KRAS is one of the most frequently mutated oncogenes found in cancer. In healthy cells, KRAS serves as an on-off switch that regulates cell growth. However, when the gene is mutated, KRAS can become stuck in the “on” position, causing uncontrolled cancer cell growth and proliferation. Several different mutations of KRAS have been identified, and commonly found types include G12C, G12V and G12D.

The KRAS G12C mutation occurs in approximately 14% of non-small cell lung cancer (NSCLC) and 3-5% of colorectal cancers.

Dr. Jane Healy
Vice president and head of oncology early development, Merck Research Laboratories

“We now know there’s no one-size-fits-all approach to treating cancer. By focusing on key oncogenes like KRAS, we’re exploring how to harness precision approaches to potentially impact tumor growth at its source.”

  • Dr. Jane Healy
    Vice president and head of oncology early development, Merck Research Laboratories

Advances in targeting KRAS

Despite decades of research, the smooth, spherical structure of the KRAS protein hindered efforts to impact its activity on a molecular level. That’s because chemists often look for places to engage with the protein on its surface, like crevices or cracks.

After 40 years of research and informed by a greater understanding of the detailed structure of the KRAS protein, scientists have discovered ways to engage with a pocket that appears on KRAS when the protein is maintained in an inactive state.

Dr. Marjorie Green
Senior vice president and head of oncology, global clinical development, Merck Research Laboratories

“As we advance our KRAS research efforts, we’re hopeful that we may uncover new ways to impact the underlying processes that fuel cancer growth.”

  • Dr. Marjorie Green
    Senior vice president and head of oncology, global clinical development, Merck Research Laboratories

Today, our scientists are building on these findings to advance potential targeted approaches in oncology research. Our precision oncology research efforts are a key tenet in our robust oncology pipeline.

Our people

Meet two scientists at the forefront of our HIV research

Two esteemed scientists share their motivations and hopes for the future of HIV research

July 1, 2025

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Rebeca Milanesi Plank, Senior Principal Scientist, Clinical Research, MSD and Bonnie Howell, Vice President, Head of Quantitative Biosciences

The field of HIV research has changed drastically in the past 40 years. In that time, we’ve evolved from helping people with HIV struggle to survive to seeing them fully thrive. Now we’re chasing a cure for HIV.

We spoke with two of our own researchers who are leading the charge, Bonnie Howell, Ph.D., and Rebeca Plank, M.D., about what drives them, what’s changed and what’s next in the HIV research landscape.

What drew you to HIV research?

Plank: I think my interest was first sparked at home by my parents, who actually met doing public health work in Chile. But it’s funny, despite that background, I wasn’t pre-med in college. I was an anthropology major. But during my senior thesis, I worked on a project around HIV prevention messaging. That stuck with me.

Image for audio file from Rebeca Plank

Howell: I can relate to that. I started working in HIV research after years of working in oncology and quickly recognized the unmet medical need. I realized that a lot of what I learned about cancer research could be applied to HIV as well.

I became passionate about HIV research because I saw it as an opportunity to change the storyline and apply my oncology experience to this different field.

In your mind, what’s been the biggest shift in HIV care?

Plank: I think the vast shift can be summed up by what I saw in med school. I was studying in San Francisco between 1996–2001, and I watched an inpatient hospital ward go from a place that housed critically ill people living with HIV to a general medicine ward full of people rightfully expecting to feel better and go back home.

And that’s all due to the fast and impactful medical innovations — such as antiretrovirals to treat HIV — that helped save so many lives.

In a field that’s been historically male dominated, how does it feel to be a female in science and HIV research?

Howell: My experience is definitely unique because I’ve been at Merck for my entire career — and I’ve been constantly surrounded by powerful and brilliant women. It’s been a privilege to be a part of a company that has empowered me to roll up my sleeves and contribute day in and day out to this important mission.

And I’m grateful for the chance to continue to add to the legacy Merck has established for itself in HIV — helping to change the way HIV has been treated since the start of the epidemic.

Plank: That said, there are still challenges facing women in HIV research. As a med student and also as a resident, it struck me that, looking around the hospital, there were relatively few women who were further along in their careers. It can be so important to see people succeeding who look like you, as role models and mentors — they show you what’s possible.

Howell: I completely agree. I also count myself lucky that I was mentored by female leaders who charted the course. Now I pay that forward and mentor the next generation of female researchers — especially those pursuing HIV.

Why do you think gender diversity is critical in HIV research?

Howell: Globally, women bear a huge brunt of this epidemic. A 2024 report showed that 53% of all people living with HIV in 2023 globally were women and girls.

It’s important to make sure that the female perspective is represented within the HIV research community, so women with HIV can have advocates who share and understand their unique female experiences.

Plank: Prior to joining Merck, during my time doing field work in Kenya and Botswana, I learned a lot about the nuances and unique hardships of the female HIV experience. Globally, advocating for herself may not always be a woman’s first priority. Not to mention that the stigma of HIV is still too prevalent around the world, which may make it harder to seek care.

Image for audio file from Bonnie Howell

What advancement in HIV research do you hope to see during your lifetimes?

Howell: A cure. Whether that’s eradicating HIV from peoples’ bodies or remission, where the virus still exists in the body but is controlled without lifelong treatment.

Plank: And then getting this cure — as well as other treatments and better methods for HIV prevention — to people in need, in the manner they need it. Access remains a huge issue, and part of that is the mode of treatment such as frequency of pills or injections. We hear consistently that having discreet treatment and prevention options would be critical.

What gives you the most hope?

Plank: So much can evolve in a single generation. These young women we’re working to help, someday they’ll be grandmothers. By empowering them with knowledge and by continuing our work in HIV, we hope to protect future generations.

Howell: The HIV community is so passionate and engaged, and we’re designing studies and treatments with those affected in mind. I’m excited to see what the future brings.

Health awareness

Navigating RSV disease: one family’s journey

As the leading cause of hospitalization for infants in the U.S., respiratory syncytial virus (RSV) can progress to severe illness for some babies

June 11, 2025

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Caring for a child with respiratory syncytial virus (RSV) can be challenging. New parents Amanda and Jeremy thought they were as prepared as possible for any illness for their daughter Charlotte.

women wearing a mask comforting a child in hospital bed

Charlotte’s first night in the pediatric ICU.

They had an established pediatrician, supportive family and friends and a variety of resources and supplies on hand to help manage symptoms. But they weren’t prepared for Charlotte to progress from having what they initially thought was a cold, with a cough and runny nose, to being admitted to the pediatric intensive care unit for RSV at only 7 months old.

RSV is a contagious, widespread seasonal infection and the leading cause of hospitalization for infants under a year old in the U.S. Infants are among the populations most at risk of contracting the severe virus during their first RSV season, which typically starts in the fall and peaks in the winter in most regions of the U.S.

Charlotte’s experience with RSV

“Charlotte was a happy, chill baby. When she wasn’t happy, it was usually a sign that she was about to get sick,” said Amanda, who as a first-time parent hadn’t thought much about RSV up until that point.

Smiling infant in crib wearing nasal cannula

On the day Charlotte was cleared to go home.

As Charlotte’s symptoms worsened, their doctor told Amanda and Jeremy what to look out for, mainly retracting or pulling in between and under the ribs, which was a sign of her struggling to breathe.

Amanda and Jeremy were surprised when Charlotte was admitted for difficulty breathing due to RSV and stayed in the pediatric ICU for a week.

Fortunately, she recovered and Amanda and Jeremy were so appreciative of her medical care. Today, Charlotte is a healthy and happy 3-year-old who loves spending time with her parents and younger brother.

Amanda understands that her family’s experience is unfortunately not unique.

"I urge all parents to understand the signs and symptoms of RSV so you can be prepared."

— Amanda

The impact of RSV on infants

RSV is a common seasonal respiratory infection that can be spread through virus droplets when an infected person coughs or sneezes, or through direct contact with the virus, like kissing the face of a child with RSV.

It’s the most common cause of hospitalization in infants under one year old in the U.S.

Common symptoms include a runny nose, fever, coughing and wheezing. While RSV doesn’t usually cause severe illness, healthy and at-risk infants can develop more severe cases that may lead to illnesses such as bronchiolitis (inflammation in the small airways of the lungs) or pneumonia (infection of the lungs) and may require hospitalization.

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It’s important for caregivers to speak with a health care provider to learn more about RSV and its symptoms.

Our people

A lifelong commitment to addressing dengue fever

How our colleague’s personal experience fueled his desire to help others

June 10, 2025

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A mosquito sitting on a baby's hand

With roughly half of the world’s population at risk of contracting dengue fever, Dr. Bin Pangilinan and his colleagues are dedicated to helping address this global health challenge.

Growing up in the Philippines, Pangilinan experienced firsthand the serious impact of dengue, one of the fastest-growing mosquito-borne viral diseases. He saw classmates become ill from the disease and, even though it was not contagious, unfortunately contracted it himself from infected mosquitos multiple times throughout his childhood. The care he received helped shape the course of his life in profound ways.

Dr. Bin Pangilinan at about seven years old

Pangilinan around 7 years old

His first encounter with dengue at age 7 landed him in the hospital, an experience marked by high fevers and severe body aches. “You would hear about outbreaks in the news, but being at the center of one was entirely different,” he said.

At age 10, a more severe episode required a two-week stay in the hospital — alarming both him and his parents. Finally, at age 15, Pangilinan was diagnosed with dengue once again, a third hospitalization disrupting his college admission tests and highlighting the disease’s unpredictability.

Joining the fight against dengue

His experience with dengue as a child ignited Pangilinan’s passion for medicine, driving him to pursue a career helping others. After completing his medical training, he faced dengue from the other side as a medical intern. “It was one of the most challenging moments in my medical career,” he said. “Treating patients impacted by dengue was a pivotal moment that further fueled my desire to help address this disease.”

Dr. Bin Pangilinan during his medical training

Pangilinan during his medical training

Pangilinan’s career journey eventually led him to Merck in 2013, where he’s worked with various groups including advocacy, medical affairs, access and policy to help address infectious diseases. His personal journey inspires his professional work with a unique empathy and understanding, particularly in his current role, where he is part of a team supporting efforts to alleviate the burden of dengue and infectious diseases.

“The commitment of my colleagues and the dedication of the global public health community to fight dengue are incredibly inspiring,” Pangilinan said.

“That passion energizes me every day and drives me to confront this disease and make a difference for those at risk around the world, especially for my hometown in the Philippines, where my story with dengue began.”

Pangilinan and his colleagues remain committed to leveraging science, innovation and collaboration to help address the impact of infectious diseases like dengue on communities around the world.

Dengue facts and figures

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Transmission and symptoms

Dengue is spread to people by infected mosquitos. Mild symptoms of dengue infection may include fever, rash and muscle and joint pain, while severe dengue disease can lead to shock, internal bleeding and even death.

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Statistics

Around 4 billion people are at risk for dengue.

Dengue is regularly found in more than 100 countries.

Around 105 million dengue infections are estimated to occur around the globe each year.

Around 4 million people may require hospitalization for dengue symptoms each year.

Health awareness

Infectious disease detection and prevention

Learn more about how to detect and help prevent many infectious diseases

June 2, 2025

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Adult holding a child while she hands on monkey bar

Infectious diseases are illnesses caused by pathogenic microorganisms such as bacteria, viruses, fungi and parasites that can spread directly or indirectly from one person to another. These diseases can range from mild to severe and can affect various bodily systems, potentially leading to significant health complications and, in some cases, death.

Vaccination is one way we can help protect against certain infectious diseases. However, in recent years, vaccination rates have been declining, which has contributed to outbreaks of some infectious diseases. For example, measles was declared eliminated; yet in 2019, there was a large measles outbreak in the U.S. with 1,274 cases reported across 31 states, which was the greatest number of cases reported in the country since 1992. And as recently as 2025, outbreaks continue to appear in parts of the U.S.

Outbreaks like these are a worrying sign of a heightened risk for the spread of vaccine-preventable diseases.

Information about certain infectious diseases 


Hepatitis A    |    Hepatitis B     |     Measles     |     Mumps   I    Rotavirus   I    I Rubella

Hepatitis A

Hepatitis A is a disease of the liver caused by the hepatitis A virus, which spreads when someone ingests the virus, usually through person-to-person contact or by consuming contaminated food or drink. Those infected may feel sick for a few weeks or several months.

Signs and symptoms of hepatitis A

  • Dark urine or clay-colored stools
  • Feeling tired
  • Diarrhea
  • Fever
  • Joint pain
  • Loss of appetite
  • Nausea
  • Yellow skin or eyes (jaundice)

Potential risks and complications

In rare cases, hepatitis A can cause liver failure and death.

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Hepatitis B

Hepatitis B is a disease of the liver that’s transmitted when blood, semen or another body fluid from a person infected with the hepatitis B virus enters the body of someone who is uninfected (e.g., during sexual contact or childbirth). The disease can range from a mild, acute illness lasting a few weeks to a serious long-term, chronic infection.

Illustration of young girl

Signs and symptoms of hepatitis B

  • Dark urine or clay-colored stools
  • Feeling tired
  • Fever
  • Joint pain
  • Nausea, stomach pain or vomiting
  • Yellow skin or eyes (jaundice)

Potential risks and complications

Approximately 15%-25% of people with chronic infection develop chronic liver disease, including cirrhosis, liver failure or liver cancer.

About 9 in 10 infants infected with hepatitis B ultimately develop a chronic infection, with the risk of chronic infection decreasing as the child gets older.

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Measles

Measles is highly contagious and can cause serious health complications, especially in children younger than 5 years old. The disease spreads through the air when an infected person coughs or sneezes, with symptoms appearing seven to 14 days after contact with the virus.

By 2000, due to effective use of vaccines along with collaborative efforts with public health organizations and health care professionals, measles was declared eliminated from the U.S. However, outbreaks continue to occur.

Learn more about measles.

Illustration of small boy with red spots on his arm

Signs and symptoms of measles

  • Fever
  • Cough
  • Runny nose
  • Red, watery eyes
  • Spots in mouth
  • Rash

Potential risks and complications

Complications from measles include ear infections in about 1 in 10 children and diarrhea in fewer than 1 in 10 cases. Some children may suffer from severe complications, such as pneumonia (infection of the lungs) and encephalitis (infection of the brain).

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Mumps

Mumps is caused by a virus that affects the salivary glands. The disease spreads through direct contact with saliva or respiratory droplets from the mouth, nose or throat. It can take two to four weeks for signs of infection to show.

At one time, mumps was the most common cause of acquired deafness in the U.S.

Illustration of boy

Signs and symptoms of mumps

  • Puffy cheeks and a tender, swollen jaw
  • Fever
  • Headache
  • Muscle aches
  • Tiredness
  • Loss of appetite

Potential risks and complications

Although rare, mumps can cause serious complications, which include inflammation of the testicles (a condition known as orchitis).

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Rotavirus

Rotavirus commonly spreads in families, hospitals and child care centers with symptoms usually starting about two days after a person is exposed to the virus. Some symptoms can last three to eight days.

Illustration of baby

Signs and symptoms of rotavirus

  • Severe watery diarrhea
  • Vomiting
  • Fever
  • Stomach pain
  • Dehydration
  • Loss of appetite

Potential risks and complications

Although usually self-limiting, severe illness can result in dehydration with shock leading to hospitalization or, on rare occasions, even death

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Rubella

Rubella, also known as German measles, spreads when an infected person coughs or sneezes. The disease is usually mild with few noticeable symptoms.

About 25 to 50% of people infected with rubella will not experience symptoms but will still be at risk of spreading the infection to others.

Illustration of girl

Signs and symptoms of rubella

  • Fever
  • Headache
  • Mild pink eye (redness or swelling of the white of the eye)
  • General discomfort
  • Swollen and enlarged lymph nodes
  • Cough
  • Runny nose

Potential risks and complications

Rubella is especially dangerous to developing babies during pregnancy. If you’re pregnant and become infected with rubella, there’s an increased risk of having a miscarriage or the baby dying just after birth. The virus can also be passed on to the baby, who may develop congenital rubella syndrome, which includes birth defects such as heart problems, hearing and/or vision problems or developmental delays.

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Understanding disease prevention 

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It’s important to learn about the potential risks of these diseases.

Talk to your health care provider about ways to help prevent infectious diseases including appropriate vaccines for you and your family.

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Vaccines: Our history, our legacy

We’ve spent more than a century working to discover and develop vaccines.