A roadmap for advancing maternal immunization against RSV

More than 60 experts, 25 organizations, 14 countries, thousands of emails ...

This is just some of what’s gone into developing a roadmap for advancing maternal immunization against one of the most common causes of severe infant respiratory infections worldwide—respiratory syncytial virus (RSV). Recently released by the Advancing Maternal Immunization (AMI) collaboration coordinated by PATH and the World Health Organization, this new resource outlines the activities needed to inform decision-making around how to bring maternal RSV vaccines from the development phase to routine use in low- and middle-income countries. Interestingly, what’s been a lynchpin for making this roadmap possible will also be key for RSV maternal immunization to have a chance at moving forward—strong collaboration across immunization and maternal, newborn, and child health communities.

So, what’s the RSV maternal immunzation roadmap all about and why is cross-sector collaboration so important? We’ve rounded up seven important things to know.

Maternal immunzation is the practice of helping a mother safeguard her baby in the first, most vulnerable, months of life, and oftentimes herself too, from certain diseases by getting vaccinated during pregnancy. It’s a powerful tool for reaching two populations through a single vaccine: pregnant women, who are often underserved in current immunization programs, and very young infants, whose immune systems are immature and require time and multiple vaccine doses to mount full defenses against many diseases. Already used safely and effectively against diseases like tetanus, influenza, and pertussis, maternal immunization may also be a promising approach for other diseases needing more prevention measures, including RSV, a significant contributor to ill-health in very young infants, and, Group B Streptococcus, the leading cause of sepsis and meningitis is young infants.

Despite its ubiquity, RSV can be hard to recognize (it is often mistaken for the common cold)—a heartbreaking error because, for infants, it can turn deadly. In these youngest children, it can lead to severe complications such as pneumonia and bronchiolitis and is responsible for 1.4 million hospitalizations in the first year of life and 120,000 deaths before five years of age worldwide each year. Infants younger than six months of age are most likely to suffer these complications, particularly in resource limited countries where healthcare resources are often unavailable or constrained. The virus is so common that it causes more than 30 million childhood respiratory infections annually. Current treatments for RSV are limited and caring for sick infants can place both an economic and emotional burden on families.

It’s not all dire, though. Vaccines against RSV are in development. Several are specifically designed to take advantage of the maternal immunization strategy and the vaccine furthest along could be available as soon as 2021.

Harnessing maternal immunization's power isn’t so simple. Even once a vaccine is approved for use, the world must be ready and able to use it—no easy feat anywhere, but particularly not in low- and middle-income countries where the ability to deliver vaccines to pregnant women within routine antenatal care may already be limited. But now is the time to remedy that. Based on a gap analysis conducted in early 2018, AMI’s RSV maternal immunization roadmap is designed to help researchers, policymakers, health practitioners, funders, and advocates at global and country levels gauge when and where to direct efforts for addressing the obstacles inherent to RSV maternal immunization introduction in resource limited countries.

The road ahead for advancing RSV maternal immunization requires venturing into largely uncharted territory and depends on information yet to come. Though maternal immunization is available in some countries, delivery challenges and information gaps prevent it from being widely used in low- and middle-income countries beyond tetanus prevention. Moving forward may not be as easy as applying the tetanus strategy to every new maternal vaccine, either; system adaptations will likely be necessary to routinely deliver RSV and other maternal vaccines in resource limited settings. Determining what adaptations are needed is a further balancing act; it is critical that strategies be applied in a way that adds value—not burden—to existing antenatal care and immunization programs.

Despite the challenges, however, we have a natural opportunity now for immunization and maternal, newborn, and child health programs to come together like never before to identify maternal immunization strategies that enhance antenatal care and immunization services overall.

The most urgent activities identified in the roadmap center on supporting vaccine development and licensure; assessing RSV maternal immunzation's potential health impact and return on investment to inform policy and financing decisions; developing communication strategies to support awareness and uptake; and ensuring countries are equipped to deliver the vaccine routinely, efficiently, and equitably once it’s available.

When an RSV vaccine eventually achieves licensure, it is destined make history not just as the first vaccine to protect against the virus, but as the first vaccine designed specifically to protect through maternal immunization. Our work to prepare for RSV maternal immunization vaccine introduction could create a blueprint for future maternal immunization vaccines, and the lessons learned can help break down the barriers to successful implementation and uptake, particularly in the face of competing public health priorities. Increased access to maternal vaccines could also serve to enhance the quality of care provided to pregnant women and their babies. Benefits could include leveraging immunization resources to improve antenatal care and overall service delivery; encouraging pregnant women to attend more well-care visits; and protecting two populations often underserved in current immunization programs: pregnant women and young infants.

No mother should lose a baby to a preventable disease. For RSV maternal immunization to have a chance at success, we must come together to answer remaining questions. Check out the roadmap to see where you can contribute to the scientific, policy, economic, regulatory, communications, and programmatic activities outlined. We all have a role to play and we must start now so that mothers can someday have the power to use maternal vaccines against RSV and other threats—no matter where they happen to live.

• A roadmap for advancing RSV maternal immunization
• Advancing maternal immunization: A roadmap brief
• Advancing RSV maternal immunization: A gap analysis report
• PATH announces new collaboration to advance maternal immunization in low- and middle-income countries
• Moving the Needle e-newsletter
• Immunization Matters e-newsletter