The 3rd ESCMID Conference on Vaccines, which was held in Lisbon, Portugal, from March 6th to 8th in 2015, was attended by more than 220 participants from 52 countries around the world, a number that highlights the continued growth of ESCMID member interest in vaccines.
The main theme of the meeting was vaccines for mutual protection, which was developed over a comprehensive series of symposia and debates that covered the entire field of vaccination. Numerous internationally renowned experts were present, providing the attendees with an unrivaled opportunity to exchange information and experiences.
The first day of the conference began with an introductory symposium dedicated to the role of vaccine-related mutual protection in disease prevention and included detailed discussions on the concept of herd immunity, the role mathematical models play in vaccine policy and the level of effective vaccine coverage that is needed to stop the transmission of disease. The European Vaccine Action Plan (EVAP) was presented by Robb Buttler (World Health Organization, Denmark), vaccine-preventable outbreaks (including measles) were discussed in detail, and the role of political commitment in reducing the population's hesitancy and refusal to receive vaccines was highlighted. Additionally, the importance of using surveillance to assure mutual protection as well as the need to improve monitoring of diseases and vaccines were considered.
The focus of the meeting then turned to influenza vaccination and the control of human papillomavirus (HPV). A symposium on influenza discussed seasonal and pandemic influenza vaccinations, taking into account the importance of mutual protection for influenza control. Additionally, advances and difficulties in the preparation of a universal influenza vaccine were presented, focusing on the role of host immune response. An HPV symposium presented the advantages and disadvantages of administering the HPV vaccination to only females versus to both females and males, including an in-depth discussion of problems related to safety and public perception, which are the great enemies of HPV vaccination programs.
The day finished with a debate on the utility of administering the 13-valent pneumococcal conjugate vaccine (PCV13) to adults, in light of the already widespread use of pediatric PCV13 in Europe. Two different positions were presented with animosity from Ron Dagan (Beer Sheva University, Beer Sheva, Israel) and Marc Bonten (University Medical Center Utrecht, Utrecht, The Netherlands), and the discussion included audience participation. The audience was divided on whether to use universal pneumococcal vaccination or a risk-based preventive strategy in adults.
The next day of the conference began with a symposium on the safety issues of vaccine administration and the potential risk of mutual protection. The reasons that are used by the public to oppose vaccination include problems created by available rapid communication channels (global media, internet, satellite TV) and the management of adverse events. It was highlighted the importance to actively involve parents in vaccination decisions and better supporting the majority of parents who vaccinate their children so they may act as powerful advocates in their communities. The degree to which an unvaccinated population impacts the greater community in which they live was analyzed, in addition to the link between risk perception and risk communication.
Focus then shifted to pertussis protection and the prevention of viral gastroenteritis across age groups. A symposium on pertussis highlighted that cases of pertussis are on the rise due to waning immunity after vaccination and strain change. These conditions have led to an increased susceptibility in the elderly and the subsequent need to guarantee protection throughout life by administering booster doses to adolescents and adults. The potential advantages of pre-partum maternal immunization or neonatal immunization were discussed, and new avenues of vaccine research were presented in detail in an engaging lecture by Stanley Plotkin (University of Pennsylvania, PA, USA). A symposium on viral gastroenteritis analyzed the epidemiology of rotavirus and norovirus gastroenteritis, showing that rotavirus will continue to circulate despite high levels of vaccine coverage and demonstrating the degree to which the importance of norovirus is underestimated. The efficacy and safety of available rotavirus vaccines were reviewed and data obtained with new candidate vaccines against norovirus were shared.
The day ended with a debate on whether we can achieve meningococcal control in Europe. The UK experience was presented to show that the meningococcal C conjugate vaccine has led to a reduction in disease caused by serogroup C, with the largest impact being due to the interruption of carriage transmission. However, due to the increased incidence of serogroups W and Y, the importance of switching from administering a monovalent C conjugate vaccine to a quadrivalent ACWY conjugate vaccine to adolescents was highlighted. Additionally, a thorough analysis of the immunogenicity, safety, and cost-effectiveness of using meningococcal B vaccines was presented.
On the final day, the focus was on recent threats of poliovirus. Data were presented to show that wild poliovirus has been detected in countries such as Israel, which has high population coverage of the inactivated poliovirus vaccine (IPV). Differences in population immune status amongst countries were presented, in addition to a discussion regarding the discrepancy between reported IPV coverage and actual poliovirus immunity, as evaluated by seroprevalence. It has been highlighted the importance of ensuring high vaccination coverage in vulnerable and hard-to-reach populations was highlighted, in addition to the need for travelers to areas where wild poliovirus circulates to be up to date in their poliovirus vaccination status. The need for a new and improved vaccine was also discussed.
Finally, a debate ensued regarding whether to administer a universal varicella vaccination to children. Adam Finn (Bristol University, Bristol, UK) was in favor of this approach because of the direct and indirect effects that are caused by varicella-related complications and hospitalizations, whereas Hanna Nohynek (National Institute for Health and Welfare, Helsinki, Finland) was against it, citing concerns related to the public health benefits of a universal vaccination program, its cost-effectiveness and the actual impact that it would have on herpes zoster rates in the population.
The conference also provided an opportunity for researchers to share original data through poster presentations and to discuss the implications of their data with the attendees. Moreover, the meeting was an opportunity to network with colleagues from different backgrounds and to develop new ideas for research.