New research has identified a potential solution for a bacterial infection that affects 160 million people worldwide. According to a study published in Nature Communications, a vaccine initially developed to combat bacterial diarrhea has shown promising results in promoting faster growth in infant nonhuman primates.
The vaccine, known as HydroVax, utilizes a hydrogen peroxide-based technology. It was created by Mark Slifka, a professor at Oregon Health & Science University’s Oregon National Primate Center. The technology has also been licensed to Najít Technologies, Inc., where Slifka serves as the company’s president and chief scientific officer. HydroVax is being used to develop vaccines against other diseases including yellow fever, West Nile, and the flu.
Campylobacter-associated diarrhea is a bacterial infection that can be mild but fatal in young children, older adults, and individuals with weakened immune systems. The Centers for Disease Control and Prevention estimates that 1.5 million people in the United States are sickened by Campylobacter each year. The infection is commonly spread through consuming raw or undercooked poultry, drinking untreated water, or coming into contact with animal feces.
Infant growth stunting, a condition in which children grow at a slower pace than normal, can be caused by a combination of poor nutrition and repeated intestinal infections. The World Health Organization reports that five or more incidents of diarrhea before the age of two are the primary cause of growth stunting in 25% of children. The new study shows that the HydroVax vaccine not only protects against Campylobacter diarrhea but also improves growth rates in vaccinated infant nonhuman primates.
The researchers found that vaccinated baby monkeys were taller than their unvaccinated counterparts when measured from head to toe. A height measurement score called Length-for-Age Z (LAZ) showed that vaccinated monkeys had a LAZ improvement of 1.28 at nine months of age. In comparison, previous studies on growth stunting prevention in human infants showed only a LAZ increase of 0.2. This indicates that the HydroVax vaccine presents a significant improvement in preventing infant growth stunting.
The vaccine also demonstrated a decrease in severe diarrhea cases among vaccinated baby monkeys. After receiving the first two vaccine doses, 55% of all vaccinated baby monkeys were protected from severe diarrhea. When both the mother and infant were vaccinated, the protection rate increased to 79%. The vaccine’s efficacy in preventing Campylobacter was slightly lower in infant monkeys compared to adult monkeys, which may be attributed to changes in the circulating strain of the bacteria and pre-existing infections in the infants.
Furthermore, the study found that none of the vaccinated infants contracted a lethal Campylobacter infection. The vaccine also reduced diarrhea-associated deaths for all causes, including bacteria other than Campylobacter, by 76%. This suggests that vaccination against Campylobacter may help reduce overall diarrhea-associated deaths.
Another surprising finding of the study was that infants born to vaccinated mothers had a significantly higher body mass index (BMI) at one month of age compared to infants born to unvaccinated mothers. This result indicates that vaccinating mothers during pregnancy provides an advantage to their infants early on, similar to the benefit of the DTaP vaccine in protecting infants against whooping cough.
In light of these findings, Slifka plans to further improve the vaccine’s effectiveness by creating a multivalent shot that targets multiple strains of Campylobacter. Additionally, combining improved nutritional supplements with vaccination will be explored to determine if it can further enhance infant growth trajectories.
The study received funding from the Bill & Melinda Gates Foundation and the National Institute of Health. It is important to note that Mark Slifka has a financial interest in Najít Technologies, Inc., the company that may have a commercial interest in the research results and technology.
All research involving animal subjects conducted at Oregon Health & Science University must undergo review and approval by the university’s Institutional Animal Care and Use Committee (IACUC). The priority of the IACUC is to ensure the health and safety of the animal research subjects as well as the people involved in the research. No live animal work can be conducted at the university without IACUC approval.