1. Introduction
Influenza viruses typically cause outbreak son a local scale and then spread to a worldwide scope including Africa, the Americas, and Oceania, with potentially severe consequences for human health and national economies [
1,
2]. According to new estimates by the United States Centers for Disease Control and Prevention, the World Health Organization (WHO) and global health partners, up to 650,000 deaths annually are associated with respiratory diseases from seasonal influenza [
3]. In the recent report of the WHO, it also claimed that another influenza pandemic is inevitable. In this interconnected world, the onset of the next global flu outbreak is only a matter of time and no conditions to be fulfilled—it will have far-reaching consequences. A severe pandemic could lead to millions of deaths and wipe out more than 1% of global GDP [
4]. “These figures indicate the high burden of influenza and its substantial social and economic cost to the world”, said Dr Peter Salama, Executive Director of the WHO’s Health Emergencies Programme. “They highlight the importance of influenza prevention for seasonal epidemics, as well as preparedness for pandemics”. Vaccination has been commonly recognized as an ideal way to prevent and control, and even eradicate, all types of flu [
5]. In the event of an influenza pandemic, the rapid development, production, and distribution of vaccines may save millions of lives. The WHO encourages countries to prioritize influenza prevention and produce national estimates to inform prevention policies, and annual influenza vaccination is recommended to prevent disease and complications from influenza infection. It is believed that influenza virus vaccine (IVV) plays an important role in preventing influenza and protecting people’s health. However, the numerous serotypes and high variability of the influenza virus challenge the research and development (R&D) of influenza vaccines. Preparation for new vaccines depends not only on domestic R&D investment but also on international collaboration. Hence, enhancing the understanding of the international scientific collaboration in the IVV field is of crucial importance for promoting technical innovation. In addition, preventing the influenza pandemic via international scientific collaboration in the IVV field is related to healthcare which is the third of the 17 Sustainable Development Goals (SDGs): ensure healthy lives and promote well-being for all ages. It can strengthen the sustainability of healthcare from following aspects: on one hand, international scientific collaboration in the IVV field can promote the common development and coordinated development of different countries’ related healthcare system to cope with the possible crisis; on the other hand, through in-depth international collaboration, the development efficiency and technological level of vaccines can be improved, thereby enhancing the effectiveness of relevant healthcare measures and achieving efficient development.
Vaccine research is closely linked to global sustainable healthcare matters and has always been a concern of many scientists. As early as 1998, Guzman et al. described and discussed the scientific production of Iberian-American countries in the fields of vaccines [
6]. Results showed that there was a discontinuity in the vaccines’ scientific production over the years and that each country had peculiar behaviors. Later, an increasing number of scholars analyzed and evaluated vaccine research carried out in different parts of the world using different bibliometric indicators in different research areas, such as the malaria vaccine [
7], childhood immunization [
8], the Ebola virus [
9,
10], nor walk viruses [
11], and so forth. Nevertheless, few bibliometric studies dealing with IVV research have been reported in literature, especially for issues of the international scientific collaboration network.
With the development of information technology and the acceleration of globalization process, the importance of international collaboration has already received theoretical and practical recognition [
12,
13,
14,
15]. Scientific research collaboration among authors from different places can facilitate keeping up with advances in findings and methods of related fields and foster more efficient development outcomes [
16,
17]. There are many scientists who work on international publications, and different scholars conduct studies from different angles (at the country or institution level, or both) and draw different conclusions. The approaches commonly used to examine international publication trends and collaboration performance of a certain research field are bibliometrics and social network analysis. Recent studies have highlighted the necessity of also considering intercity collaboration to fully understand cooperative and innovative activities [
18,
19]. However, studies examining the relationships among these three levels of international scientific collaboration are not yet fully developed.
In our previous work, we designed a technology classification system and search strategy for the identification of the IVV field and presented a global analysis of the IVV field’s technology resource distribution and development characteristics [
20]. Uneven distributions of technology resources and an imbalance in the national scientific and technological strengths in IVV require extensive R&D collaboration at the country and city levels as well as the more specific institution level. In 2006, the WHO launched the Global Action Plan for Influenza Vaccines (GAPI), calling on all countries of the world to take a positive position on the research and development of effective vaccines. Three years later, the WHO issued a new Global Action Plan for Influenza Vaccines (GAP II) to succeed the activities of GAP I. Greatly supported and promoted by the WHO, newer and expanded R&D alliances have been formed in both developed and developing countries, and progress is being made with new scientific achievements and technologies [
21]. The objectives of this paper are to create a map of multilevel international scientific collaboration within the IVV field around the world after the GAPs were put into effect and to discuss the similarities and the differences between three types of collaboration networks. The paper intends to draw the policy implications to enhance the further research in IVV field which hope to prevent the disease and promote the sustainability of global healthcare.
The remainder of this paper proceeds as follows:
Section 2 describes the research framework for the multilevel analysis and presents the research questions.
Section 3 introduces the data and methods.
Section 4 analyzes the characteristics of the global scientific collaboration network in the IVV field, discusses the empirical results, and probes how these findings can enlighten international collaboration activities. Concluding remarks are provided in the last section.
5. Conclusions and Discussion
From the perspective of multilayered relation networks, this paper constructs a multilevel analytical framework of international scientific collaboration. We longitudinally examined the regional distribution, dynamic changes, and common themes of collaborations (at the country, city, and institution levels) of the IVV field, based on scientific publications from 2006 to 2013 collected from the WoS database. The results suggest that multilayered analysis helps provide a more comprehensive understanding of international scientific collaboration. The following conclusions are drawn from the analysis of the three levels of international scientific collaborations in the IVV field from 2006 to 2013.
The three kinds of collaboration networks all suggest strong core-periphery characteristics and dynamic structures. The values of degree centrality of collaboration networks are subject to segmented Zifp-Pareto distribution.
Although the number of multinational papers has shown an obvious increase in recent years and its proportion also exhibits an overall upward trend, the global scientific collaboration network of IVV is far from being complete and suggests strong core-periphery characteristics. Its center is formed by the United States and some European and Asian countries, while many other countries are in the periphery, playing the role of participants; and so it is with the city-level and institution-level collaboration networks. At the city level, for instance, the core members are very limited and include Atlanta, London and Tokyo. HL-type, LH-type, and LL-type cities have the most in number.
Also, the network positions of countries, cities and institutions vary with time: some present small fluctuations and others make considerable changes during the investigation periods; in terms of direction of movement, they moved from central to relative peripheral positions or in the opposite direction. For example, cities, such as London and Tokyo, and institutions, such as the University of Wisconsin and St. Jude’s Children’s Research Hospital, have always been on the cutting edge. Atlanta and the CDC have become collaborating centers of global IVV research, but some have slipped backwards, such as Memphis, TN, USA; Marburg, Germany; and Herts, United Kingdom.
Despite the regional imbalance of scientific papers distributed in the countries, cities, and institutions, the degree centrality distribution of the three levels of international scientific collaboration networks in the IVV field follows the Zipf-Pareto distribution. After that, the intensity of cooperation of all countries, cities, and institutions can be divided into high, medium, and low degrees according to the curves’ hierarchical characteristics.
It is known that there exist corresponding relationships among countries, cities, and institutions for geographical location; however, their associated categories, network locations, and changing trends are all non-conformal.
At first, all partner countries, cities, and institutions are classified into four types (HH, HL, LH, and LL); however, the associated categories of one institution, its city, and its country differ universally. Secondly, there is a real asymmetry between several cities and their countries’ positions in the corresponding collaboration networks. The United States remains substantially ahead at the country level; however, American cities are not always in the lead at the city level. This could be mainly due to more equally distributed research over the cities in the United States, in contrast to countries such as the United Kingdom, Canada, and Australia, which have highly concentrated and dependent research in some specific cities. In addition, there are some cities that have reached global prominence whose countries do not belong to the HH type, such as Auckland, New Zealand; São Paulo, Brazil; Mexico City DF, Mexico; and Seoul, Korea.
Because all three levels change with time, and the trend of each change is not similar, it is not appropriate to conclude how the three levels as a whole are behaving. The ranking changes of multinational paper counts of most institutions and their cities and countries did not take place at the same time. China, for instance, has formed good international collaboration networks in the IVV field. Owing much to emphasis placed on vaccine R&D expenditure and the demand for biomedical advances, the world has witnessed a spectacular rise and development in the international collaboration of Chinese cities in recent years. To be specific, six cities including Hong Kong, Beijing, Shanghai, Harbin, Tianjin and Shantou have entered the HH quadrant and in particular, Beijing has risen to the world’s fourth place from 2012–2013.Nevertheless, at the institution level, the universities, enterprises, and research institutes of Beijing did not even make the top 10. As for this situation, promoting the engagement of multileveled sectors in governance for health is required.
In the context of implementing a global action plan for influenza vaccines coordinated by the WHO and the sustainability of healthcare, each government should enhance the optimal design for policy relevance. Local governments should boost their presence in international scientific collaboration activities, as well as change and improve the external environment, as far as possible to fit into the global competition and opportunities. Every institution should identify partners that have wider collaborative breadth and deeper collaborative depth, then increase their engagement in international collaboration. On the basis of those endeavor, we consider that the ability of global IVV research can be enhanced to improve the preventive effect of IVV, which then can help us to prevent the disease, protect people’s health, and maintain social stability. Therefore, to some extent, it can make contribution on achieving the SDGs: ensure healthy lives and promote well-being for all ages. Furthermore, in order to achieve the sustainability development of healthcare, such as common development, coordinated development and efficient development, the specific manners to stimulate international collaboration in the IVV field still need further discussion. For instance, governments can establish a collaborative fund or a transnational scientific program for advancing the international collaboration in the IVV field.
This kind of multilevel analytical framework and analysis process can give an integrated pattern of international scientific collaboration. It can also be extended for utilization in other technological fields. Nevertheless, the paper has its limitations. First, the data of this study simply comprise published papers. In a follow-up study, patent data and vaccine business cases will be added. With this data, the relationship between scholarly literature and patent documents in the IVV field may be uncovered as a result of tracing citation links by both scientific fields and technological sectors. In addition, by matching the affiliated addresses both in papers and in patent data combinations, we intend to assess the extent of the overlap between the two communities and to identify the role of key institutions in the process of knowledge transfer. A well-tailored case study, such as the needle-free nasal spray formulation H5N1 flu vaccine test lesson, and well-developed collaboration network analysis for a specified country (or city or institution) should be helpful to the recognition of different collaborative patterns. Second, although we depict a cross-correlation map to show institutions that are working on similar topics, the relativity between the number of multinational papers and the similarity of research themes has not been analyzed fully and specifically by correlation analysis. Neither has the relationship between the three levels. What is their inner link? What is their external connection? Could they replace or supplement each other? These topics will be covered and probed in our future study.