Pneumonia can occur across life’s stages—prevention should too

Most vaccination programs focus on discrete life stages, such as childhood, but this can mean that other at-risk stages fall through the cracks. With a life-course approach, in which vaccines are given through all life’s phases, people are better protected at critical times that are often otherwise missed.

Many experts believe that this approach is key for preventing pneumonia.

“From bacteria, to viruses, to pollution, pneumonia has many causes that have fueled its persistent reign as the world’s number one killer of children before age five. Yet, the dangers are even more nuanced,” says Bruce Innis, MD, PATH Global Head of Respiratory Infections and Maternal Immunization.

“Risks can be greater if a person is very old or young, has underlying health issues, is pregnant, or lives in lower-income regions—all factors that necessitate, yet too often impede, vaccine access.”

With 2.5 million deaths due to pneumonia each year worldwide (670,000 of them children), we need more than one strategy to fight this multiheaded beast. That’s why PATH is part of a global effort investing in a diverse arsenal of integrated prevention, treatment, and diagnostic measures as the best path to victory.

“A goal and best practice named in the Immunization Agenda 2030, life-course vaccination is a way to add more layers of defense, including against pneumonia,” adds Dr. Innis.

As such, PATH is deploying our vaccine development and delivery expertise to reach underserved people where and when pneumonia is likeliest to strike—including early infancy, pregnancy, and childhood. And we’re doing so against some of pneumonia’s toughest pathogens.

Respiratory syncytial virus (RSV) is the top cause of severe respiratory infections and hospitalization in infants worldwide. It’s associated with a staggering 40 percent of severe pneumonia cases in the first year of life and 1 in every 28 deaths before 6 months of age—mainly in the world’s poorest areas.

“RSV immunization has the potential help keep millions of children out of the hospital, prevent thousands of deaths, reduce burdens on families, and free up resources for other health priorities, but the historic lack of licensed vaccines has been a problem,” says Deborah Higgins, Director of PATH’s RSV Vaccine Project.

“For young infants, direct vaccination tactics are rarely options because their immune systems can be too immature to mount an effective response. We urgently need other ways of providing these babies with the antibodies they need.”

Fortunately, some promising early prevention products for RSV could be on the market soon.

One is a vaccine designed for maternal immunization (or vaccination in pregnancy)—an approach with a successful track record against tetanus and other pneumonia-causing pathogens like influenza and pertussis. A pregnant person’s heightened antibodies can transfer to a baby in utero and protect for months after birth.

In fact, a maternal RSV vaccine candidate recently demonstrated positive safety and efficacy results in Phase 3 clinical evaluation, meaning approval could be around the corner.

The other product is monoclonal antibodies (mAbs), which are manufactured antibodies that can be given to a newborn at birth or soon thereafter to protect in early life. The first single-dose mAb for RSV was recently approved in Europe, and other promising candidates suitable for use in low-income contexts are in development as well.

Both strategies involve reaching life stages less conventional for vaccination and navigating some unfamiliar territory. First, RSV will be a new disease target for countries. Second, service delivery (especially for immunization and antenatal care programs) will likely need to be adapted in new ways. So, global, regional, and country consideration and planning around what introduction will take needs to start now.

“PATH is helping by partnering on several studies to estimate potential costs and health impacts of delivering RSV maternal vaccine and/or mAbs,” says Ranju Baral, PhD, Health Economist at PATH. “This kind of information will help countries decide how RSV prevention can fit within their public health priorities.”

PATH is also collaborating to raise RSV prevention awareness, track prevention products in development and clinical trials, landscape pregnancy registries for monitoring vaccine safety, inform service delivery for antenatal care timing and RSV vaccination windows, and advance assay standardization for consistent RSV vaccine testing. A bonus is that much of this work informs strategies beyond RSV too.

In addition to preventing disease in young infants, maternal immunization is also a robust tool for preventing respiratory infections with heightened risks during pregnancy, like COVID-19.

“During the pandemic, we’ve seen increased risk of severe illness in pregnant populations and complications in their newborns associated with COVID-19—emphasizing the importance of vaccination for safeguarding maternal health and pregnancy outcomes,” says Sadaf Khan, DrPH, Program Advisor for Maternal, Newborn, and Child Health and Nutrition at PATH.

The pandemic has highlighted how factors like pregnancy status can drive vaccine inequity. While maternal immunization isn’t yet being used to its full, lifesaving potential—neither as a broader health service nor against COVID-19 (despite the World Health Organization’s interim recommendations)—momentum blossoming out of the pandemic is encouraging.

For instance, more than 120 countries (as of October 2022) explicitly recommend COVID-19 vaccination for some or all pregnant people. Global collaborations like COVAX’s Maternal Immunization Working Group and other initiatives are further spurring progress. Also, PATH’s aforementioned maternal immunization work informs the global COVID-19 response along with our COVID-19 Maternal Immunization Resource Library, which we developed in collaboration with the World Health Organization.

In a life-course approach, childhood vaccination is a cornerstone, including for pneumococcus—a top cause of deadly pediatric pneumonia as well as meningitis, sepsis, and debilitating middle ear infections.

Pneumococcal conjugate vaccines (PCVs) have significantly reduced child deaths and illnesses from this bacterium, but they also have a history of price and supply barriers leaving millions of kids without access.

To address a need for more sustainably affordable and accessible PCV options, PATH came together with Serum Institute of India, researchers in Africa and India, and others to develop PNEUMOSIL®—a state-of-the-art PCV now saving lives on the global market.

At just US$2 per dose, the vaccine is priced roughly 30 percent less than Gavi, the Vaccine Alliance prices for predecessor PCVs and dramatically less than PCV prices typically available to non-Gavi countries. PNEUMOSIL can also be produced at high volume and is designed to cover certain varieties (or serotypes) of pneumococcus causing the most disease in low- and middle-income regions.

In addition to tackling price and supply barriers, PATH also maintains a PCV cost calculator to help countries analyze costs when choosing between the different PCVs available. We’re also supporting efforts to develop new PCVs that increase the number of vaccine serotypes to expand the potential to prevent several deadly and emerging serotypes not yet covered by existing PCVs.

Immunization is even more powerful in tandem with other pneumonia interventions. Vaccines along with oxygen therapy, pulse oximetry, antibiotics, clean air, good nutrition, and breast milk can hit pneumonia from various angles and at life’s most critical junctures. Pair this toolkit with other disease control efforts, like those for diarrhea, and the lifesaving potential skyrockets.

Whether a person has just been born, is in later life, is expecting a baby, or lives in a poor or remote part of the world shouldn’t determine their access to disease prevention. That’s why life-course vaccination is so important.

To defeat pneumonia, we’re going to need to go where immunization has never (or rarely) gone before. At PATH, we’re up for the challenge.

Editor’s note: PATH's style guide prioritizes gender neutral language when discussing pregnancy, which can be experienced by all genders. A few instances linked in this article refer to recommendations or language drawn from other organizations and, therefore, may not align with our written style guide. We will continue to promote inclusive language in our sector and in our work—and hope to see this reflected in all public health applications. \

( Video courtesy of IMPRINT. )