Neonatal and early infant morbidity and mortality remains the highest in low and middle-income countries, often caused by infections that could be prevented by vaccines.
A critical window of susceptibility, however, remains in the first 3 months of life when the newborns have only received a very limited number of vaccines. Following the vaccines against polio, hepatitis and tuberculosis (TB) given at birth, the Expanded Programme on Immunisation (EPI) schedule only sets in at 2 months of life, and several doses of the same vaccine are needed to achieve full protection.
Immunizing mothers during pregnancy against vaccine-preventable infectious diseases, such as tetanus in Africa and pertussis and flu in other settings, is an attractive strategy to reduce the infant mortality rate and has already been implemented successfully. The vaccines given in pregnancy induce antibody in the mother which then get transmitted to the baby through the placenta in the last trimester of pregnancy and safeguards the infant through passive protection. The strategy is already widely implemented to combat tetanus in newborns and has had an amazing impact worldwide. More vaccines can potentially be used in this manner, provided they are safe for mothers and babies.
In November 2015, the Vaccines and Immunity Theme (VIT) organized the 3rd International meeting for Neonatal and Maternal and Immunisation (INMIS) in The Gambia, which attracted over 100 international visitors from 22 countries and relevant speakers addressing the different quantitative and qualitative aspects of the ongoing research and future perspectives (www.inmis.org/). Participants came from all stakeholder backgrounds: academia, public health, including WHO Afro, Bill & Melinda Gates Foundation, Programe for Appropriate Technology in Health (PATH) and industry.
As vaccination against tetanus is already implemented in Africa, and vaccines against flu and pertussis have been introduced in Europe, Noth America and Australia. The key areas for discussion included the development and utilization of vaccines for pathogens that affect maternal and child health, such as pertussis, influenza, group B streptococcus, respiratory syncytial virus, meningococcus and pneumococcus. lessons learnt from these clinical trials and implementation programs can now shape the roadmap for research and practice and ultimately influence policy for these interventions at the WHO level.
To assess the safety and immunogenicity of vaccines given at pregnancy in The Gambia the VIT Theme secured funding from the Global Health Trials scheme, the European Union (EU) and the Meningitis Research Foundation for 3 clinical trials to be conducted at the MRC Unit The Gambia. During the next Quinquennial 2016-2021, the VIT will conduct a portfolio of studies to see if vaccines given to pregnant women against pneumococci, Bordetella pertussis and meningococcus A can be shown to induce protection in babies. We will carefully monitor safety and measure immune responses in mothers and babies to also clarify if vaccines given in pregnancy have a knock-on effect on the immunity induced in the offsprings, once they receive their own vaccinations.
For these trials, which are sponsored by the MRC, participants will be recruited at our established community sites and be carefully followed during pregnancy, including the use of our new ultrasound facility to accurately date the pregnancies. Following extensive community sensitization, the trials are implemented by our experienced teams in the field, lab and data management, and are led by Dr Ed Clarke, Head of Infant Immunology and Professor Beate Kampmann, Theme Leader for VIT. The trials will provide many opportunities for us to conduct novel laboratory-based science, which will explore detailed responses to the vaccines using systems vaccinology approaches, along with conventional read-outs of vaccine responses. They will also provide us with an opportunity for qualitative research into the acceptance of vaccines in pregnancy, which is an important complimentary part in this new and exciting field. There will be a number of training opportunities associated with the studies. Careful safety oversight is in place.