Vaccinology has repeatedly held the future health of humanity in its hands. The specialist branch of medicine has historically been called on to save lives through the clinical formulation of a vaccine for diseases such as polio, measles and tuberculosis, and there are a multitude of other conditions that have seen an impactful response from the scientific community.
VIDA in the Faculty of Health Sciences at Wits University works intensively in the field and has valuable experience and is poised to contribute at a time when a vaccine for the novel SARS-COV-2 virus is sought. Academics and postgraduates at VIDA (previously known as Respiratory and Meningeal Pathogens Research Unit; RMPRU) have previously focused on the epidemiology and clinical development of lifesaving vaccines against pneumonia and diarrhoeal disease.
Many of these Wits heroes who wear lab coats have informed the World Health Organization (WHO) on recommendations that include the use of the lifesaving pneumococcal conjugate vaccine, rotavirus vaccine, and influenza vaccination for pregnant women.
Conceiving new hope for newborn babies
One of the projects that inspired hope through vaccinology was VIDA’s contribution to the development of a vaccine to safeguard pregnant women against stillbirth and infant death. The body of work resulted in the world’s first maternal multi-valent Group B Streptococcus (GBS) vaccine trial, which if 80% effective and reached 90% of women, could potentially prevent 231,000 infant and maternal GBS cases.
GBS is carried by up to a third of pregnant women (usually with no symptoms) but it is their babies that are more vulnerable to the infection, as their immature immune systems cannot fight the multiplying bacteria. If untreated, GBS can cause serious infections, such as meningitis and septicaemia in young infants, and could also cause stillbirths. Babies surviving this infection can develop permanent problems including hearing or vision loss, or cerebral palsy.
Although GBS vaccine development has been ongoing since the 1970s, there are no vaccines currently available to immunize pregnant women to protect the foetus and their young infants. This is the reality, despite the stark contrast that GBS accounts for more than the combined neonatal deaths from tetanus, pertussis [whooping cough] and respiratory syncytial virus, for which maternal vaccines are already in use or further advanced in development.
The clinical development of a multi-valent GBS vaccine currently underway in South Africa is especially important as the highest incidence of invasive GBS in young infants globally has been reported here for the past 20 years. Furthermore, pioneering work by VIDA indicates that at least 1,250 South African women would have a stillbirth due to GBS every year. This further emphasises the need for a GBS vaccine, since GBS prevention strategies such as intrapartum antibiotic to colonized women in labour only partly reduce disease in infants.
To have a GBS vaccine licensed, VIDA is also leading large scale natural immunity studies in mother-newborn dyads, to accelerate the licensure pathway to GBS vaccine for pregnant women.
Identifying why babies were stillborn
VIDA continued its mandate to advance paediatric medicine and, in 2019, pursued research to identify methods to accurately determine the causes of stillbirth in South African women. A pilot study undertaken at the Chris Hani Baragwanath Academic Hospital in Soweto informed the rollout of Minimally Invasive Tissue Sampling (MITS) in low- and middle-income (LMIC) countries globally via CHAMPS – the Child Health and Mortality Prevention Surveillance Network.
The researchers found that 20–25% of stillbirths occurred due to invasive bacterial infections, and others due to maternal medical conditions such as hypertension and diabetes, and obstetric complications. Also, invasive bacterial disease was either the immediate or underlying cause of death in 57.5% of all neonatal deaths. The novel approach to ascertaining cause of death attribution, also spotlighted that 74.4% of the neonatal infection-related deaths were hospital-acquired, mainly due to multidrug-resistant bacteria.
The MITS study revealed the issue of inadequate infection control practices in public healthcare facilities, which in the context of Covid-19 has hit headlines and requires immediate action. With higher levels of awareness around Covid-19, we need to ensure that we strengthen infection control measures moving forward.
The reality is that we will not destroy the Covid-19 virus and in fact, the natural trajectory of the virus is set for an increase in infection rates in the next few months, irrespective of what level of the lockdown exists. Whilst this is the first wave of the Covid-19 pandemic, in all likelihood we will experience at least 2-3 waves for the next 1-2 years. Hence, we are in for a long haul, at least until we can secure some level of community immunity, ideally with a vaccine, which hopefully will become available soon.
The work being done today by the medical and scientific communities is critical for the health of all people. Vaccinology can and will play its part, as it simultaneously reminds us that every life matters in the context of medicine. Let us remain hopeful, as there are experienced minds at work to enable us to secure future healthcare solutions. In this regard, Professor Madhi’s research unit is preparing to launch the first COVID-19 vaccine studies in Africa shortly. DM
Professor Shabir Ahmed Madhi is the Director of the Medical Research Council Vaccines and Infectious Diseases Analytical Research Unit (VIDA, previously known as Respiratory and Meningeal Pathogens Research Unit; RMPRU); and Department of Science and Technology/National Research Foundation Research Chair in Vaccine Preventable Diseases at the University of the Witwatersrand.
Listen to the Wits Impacts For Good podcast on 702 with Professor Madhi: