FAU Researchers identify new vaccination barriers.

Vaccinations against common and serious infectious diseases have had more of an effect than any other medical advance during the 20th century on improving human health, surpassing even sanitation and potable water provision. From global eradication of smallpox in 1980 to developing effective and safe mRNA vaccines for COVID-19 in 2003, vaccinations have proven crucial in saving millions from premature deaths or hospitalizations from infectious disease outbreaks both adults and children.

These remarkable efforts involve coordinated local, regional, national and international organizations along with dedicated clinical and public health professionals working across borders. Unfortunately, decreasing vaccination rates now threaten the enormous positive impacts vaccination has in both the US and globally.

These barriers include increasing vaccine hesitancy in the United States. Florida Atlantic University’s Schmidt College of Medicine researchers and colleagues detail new clinical and public health challenges related to vaccination of U.S. adult citizens in an article published online prior to print in The American Journal of Medicine.

“Within the U.S., continuing efforts of clinical and public health professionals along with technological innovations in vaccine development provide promise for a bright future”, stated senior author Charles Hennekens M.D. – Sir Richard Doll Professor of Preventive Medicine and Academic Advisor in Population Health & Social Medicine departments of medicine at Yale.

Health care providers and public health officials must recognize that increasing vaccination rates alone are insufficient; surveillance-containment requires rapid detection and reporting of confirmed cases, immunizing household members and close contacts within 24 hours, using isolation as necessary, rapid antiviral or antibiotic medication; social distancing techniques, respiratory hygiene etiquette practices or masking as required, home or large scale quarantines as appropriate, masking; as well as continuing and expanding efforts on part of U.S. providers if successful in these efforts.” Success requires joint efforts by health care providers with public health officials both parties working on behalf of both parties involved.”
Charles Hennekens was appointed first Sir Richard Doll Professor for Preventive and General Medicine at Florida Atlantic University.

Health care providers in the U.S. face considerable difficulty in attaining high vaccination rates against COVID-19, respiratory syncytial virus (RSV), and influenza; which present particular risks among elderly and immunocompromised patients. They caution about potential concerns surrounding recent reports of H5N1 influenza strain emergence in China.

Hennekens stated, “the pneumococcal vaccine has been demonstrated safe and effective through multiple randomized trials for adults aged 18-79 years, including those over 80. This vaccine may prove especially valuable to elderly, immunocompromised individuals and those at high risk for pneumonia; thus making it especially helpful.” Furthermore, herpes zoster (shingles), affects one out of every three people over 65 and results from varicella zoster virus reactivation from previous chickenpox infections that reactivation from previous chickenpox infections; debilitating complications may ensue making these individuals particularly susceptible compared with immunocompromised individuals; therefore our FDA-approved vaccine makes for safe, effective protection.”

Though measles was eliminated in 2000, its challenges remain significant both clinically and publicly. Recent outbreaks in areas with lower vaccination rates combined with recent vaccine hesitancy has lead to herd immunity being lost; by July 2023 116 out of 195 countries reported lower measles vaccination rates than expected (WHO estimates this has prevented over 154 million premature deaths since 1974, 101 million among infants).

“Vaccinations against 14 diseases have contributed to a 40% global reduction in infant deaths since 1994. Within the U.S. alone, from 1994-2024 measles vaccination is estimated to have prevented 508 million cases, 32 million hospitalizations, and over one million deaths,” according to Hennekens. Furthermore, maintaining herd immunity remains key in order to stop future outbreaks that lead to subsequent measles outbreaks and deaths.

Last August, the World Health Organization declared mpox an international public health emergency. Mpox is a variant of smallpox that had previously been managed through vaccination campaigns since 1980 but these had seen decreased coverage since its eradication.

“The spread of new variants, particularly Clade Ib, poses increased mortality risks,” according to Hennekens. A recently developed vaccine has proven highly successful at restricting its spread; particularly in areas at increased risk, like sub-Saharan Africa. Global vaccination efforts face specific difficulties related to limited supplies and improper coverage for vulnerable populations.

The authors conclude that in the U.S., ongoing efforts by health care and public health professionals combined with advances in vaccine technology offer great hope of eliminating or even eradicating many infectious diseases altogether. Achieving such goals requires sustained collaboration as well as increasing vaccination rates.

John Dunn is a second-year FAU medical student studying under Barry R. Davis (MD, PhD) of Schmidt College of Medicine; Alexandra Matarazzo also from Schmidt; Yanna Willet a premed student attending Virginia Tech; Sadine Al-Farauki who just started Ross School of Medicine after being an FAU graduate; Dennis G Maki MD who holds the Ovid O. Meyer Professorship emeritus chief infectious diseases at University of Wisconsin School of Medicine & Public Health
Journal reference:Dunn, J. and colleagues (2024). New clinical and public health challenges associated with vaccination of U.S. adult population.The American Journal of Medicine doi.org/10.1016/j.amjmed.2024.09.025.