Bibliometric Analysis of Pfizer-BioNTech (BNT162B2): A COVID-19 Vaccine

© The Author(s) 2021. Open Access. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License which permits unrestricted use, sharing, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. Hassan & Ara | J Pure Appl Microbiol | 15(3):1211-1229 | September 2021 Article 7039 | https://doi.org/10.22207/JPAM.15.3.11


INTRODUCTION
Coronavirus disease 2019 (COVID- 19), is a highly transmissible global pandemic. It was 1 st detected and identified in Wuhan, China, in December 2019. It causes an infection in nose, sinuses, upper throat or lower respiratory tract (windpipe and lungs). Some of the major sympotoms are fever, coughing, shortness of breath, trouble breathing, fatigue, chills, sometimes with shaking, body aches, headache, sore throat, congestion/runny nose, loss of smell or taste, nausea, and diarrhea. The virus can lead to pneumonia, respiratory failure, heart problems, liver problems, septic shock, and ultimately may lead to death. According to WHO, globally, there have been 160,074,267 confirmed cases of COVID-19, including 3,325,260 deaths (till 14 th May, 2021).
Bibliometrics is the qualitative and quantitative analysis of scientific articles, books, or the chapters of a book. It is widely used for analysis of the research outputs of individual authors, institutes, and countries. It can also help in identifying the impact of research in a particular field. The new and emerging areas of research can also be explored with the help of bibliometrics. It may help to identify the potential research collaborators and find suitable sources or journal in which the research documents can be published [1][2][3][4] . However, there are a few issues related with bibliometric analysis. The citation rates vary by subject or field. For example, the top-ranked journals in mathematics have impact factors of around 3; while, in cell biology the journals may have 30 impact factor. Similarly, the h-index varies by field. The life scientists, physicists and social scientists top out at 200, 100 and 20-30 (h-index), respectively. This indicates the differences between various disciplines. The citation is also database dependent. For example a researcher in Web of Science may have an h-index of 10. But in Google Scholar he/she may have 20 h-index [5][6][7] .
The scientific literature about COVID-19 has exponentially increased and various bibliometric studies are reported in this regard  8 . Similarly, Saed H. Zyoud explored the Arab region's contribution to global COVID-19 research. Precisely, they retreived a total of 143,975 publications about COVID-19. The Arab region contribution was 4.25% or 6131 documents 9 . Its worthy to note that Chinese government has implemented substantial policies to prevent and control the COVID-19 epidemic. Jiang Wu et al., performed bibliometric analysis to understand the transitions and effects of policies over time. A total of 366 policies of epidemic prevention were collected and bibliometrically analyzed 10 [15][16][17] .
Recently, Cascella et al., provided detail information about the significant progress in the development of novel therapeutics and vaccine development for COVID-19. Currently, a variety of therapeutic options are available which are either approved by U.S. Food and Drug Administration (FDA) (Emergency Use Authorization ( EUA) or being evaluated for COVID-19. For example the anti-SARS-CoV-2 monoclonal antibodies (e.g., bamlanivimab/ etesevimab, casirivimab/imdevimab), antiinflammatory drugs (e.g., examethasone), immunomodulators agents (e.g., baricitinib, tocilizumab) etc. We will specifically highlight the antiviral drugs 18 . Initially Hydroxychloroquine and chloroquine were proposed as antiviral treatments. However according to recent findings the use of hydroxychloroquine with or without azithromycin in hospitalized patients did not improve the clinical status or overall mortality compared to placebo [19][20] . Lopinavir/ritonavir is an FDA-approved combo therapy for the treatment of HIV. It was also proposed as antiviral therapy against COVID-19. However a recent data reported no benefit against COVID-19. Currently it is not indicated for the treatment 21 . Ivermectin is an FDA-approved anti-parasitic drug proposed for the treatment of COVID-19. However no significant efficacy was observed in recent trial. Therefore it is currently not indicated for the treatment of COVID-19 22

Data sources and visualization
On 13 th May, 2021, we retrieved the data from Scopus, one of the largest databases in the world. In search field the following term was used i.e. "Pfizer-BioNTech" OR "BNT162b2". It was searched in article titles, abstracts and keywords i.e. TIT/ABS/KEYWORDS. We quantitatively and qualitatively analyzed in Microsoft Excel 2013. For science mapping and visualization, we used VOSviewer version 1.6.9 and Bibloshiny (Bibliometrix).

RESULTS AND DISCUSSION
Total one hundred and seventy three (n=173) research documents are published about Pfizer-BioNTech vaccine. It majorly comprised of articles (n=91), reviews (n=42), letters (n=22), notes (n=12), editorials (n=6), short surveys (n=4) and errata (n=1). For detail analysis we focused on articles and reviews (n=133) with 1359 citations. One of the advantages of biblioshiny is that it can provide detail information about the local and global citations. Local citations are the citations which are received from documents included in data.While, global citations are the total citations that an article has received from other documents indexed in a database (WOS, Scopus, etc). The local and global citation details of only cited documents are provided in Table 1.
The highest citations are received by three documents which are published in "New England Journal of Medicine". In the 1 st report (TC=686), the authors performed a multinational, placebo-controlled, observer-blinded, pivotal efficacy trial (conducted in USA and Germany) to test the efficacy of BNT162b2 vaccine. 21, 720 participants were given BNT162b2 and 21, 728 with placebo injections. The author claimed and concluded 95% efficacy of BNT162b2 in preventing Covid-19.
In the 2nd most cited document (TC=219), the authors explored the efficacy of two lipid nanoparticle-formulated vaccine candidates (a) BNT162b1 and (b) BNT162b2. Two groups of individuals 18 to 55 years and 65 to 85 years were included in the placebo-controlled, observer-blinded, dose-escalation and phase 1 trial conducted in USA. The author confirmed the safety and immunogenicity data of (BNT162b1) trial conducted in Germany.
In the 3 rd highest cited report (TC=51), the authors obtained data from Clalit Health Services (CHS), the largest health care organization in Israel. recisely, they evaluated and discussed the effectiveness of the BNT162b2 mRNA vaccine. 1,163,534 vaccinated cases were included in this study along with 596,618 placebo/control subjects. During the period from 14 to 20 days after the first dose, the authors analyzed effectiveness against, documented infection, symptomatic Covid-19, hospitalization, severe disease and death. 46%, 57%, 74%, 62% and 72% effectiveness were (respectively) noted for above four categories. While, during the period from 21 to 27 days after the first dose, the estimated effectiveness for these outcomes was 60%, 66%, 78%, 80% and   84%, respectively. Based on the data, the authors suggested that the BNT162b2 mRNA vaccine is effective against Covid-19. The 4 th most cited document is about the summary of "the advisory committee on immunization practices' interim recommendation for use of pfizer-BioNTech COVID-19 Vaccine -United States, December 2020". "On December 12, 2020, the Advisory Committee on Immunization Practices (ACIP) issued an interim recommendation for use of the Pfizer-BioNTech COVID-19 vaccine in persons aged ≥16 years for the prevention of COVID-19".
The 5 th most cited work (TC=34) is published in Science. In background, the authors provided brief information about a novel SARS-CoV-2 variant, lineage B.1.1.7 discovered in UK. The authors tested efficacy of BNT162b2 (30 μg) for neutralization of SARS-CoV-2 Wuhan and lineage B.1.1.7. The data suggested that new line "will not escape" BNT162b2-mediated protection.   Fig. 3A,B. The co-authorship network for institutes.

AUThORS, UNIVERSITIES AND COUNTRIES
Based on biblioshiny (bibliometric) analysis, 1160 authors have contributed to all publications. Fourteen (n=14) authors published single-authored documents and 1146 authors published multi-authored documents. The documents per author was 0.119, while authors per document was 8.41. Collaborative Index (CI) can be used as a quantitative measure of research collaboration. It was proosed by Lawani in 1986. It can be calculated by the following formula.

C= Total Number of Authors/ Total Number of Papers
By biblioshiny we calculated the CI, and it was found to be 9.47 Lotka's Law is normally used to provide breif informaqtion about the frequency of publication of authors in a particular research field. Sometimes it is called "inverse square law", which means that there is an inverse relation between the number of publications and the number of authors. It is depicted by 1/n 2 . In other words 60% of authors will have only one publications. 1/n 2 can be further extrapolated, for example, (1/2 2 times 60) and (1/3 2 times 60). This means that 15% and 7% authors will have two and three publications, respectively [23][24] . By biblioshiny we applied Lotka's law to depict the authors frequency. Its apparent from the Fig. 1, that 1097 and 50 authors were involved in one (n=1) and two (n-2) publications, respectively.
The collaboration among authors, institutes, and countries could be explained by the fact that;  neutralization by monoclonal and serumderived polyclonal antibodies 6. BNT162b vaccines protect rhesus macaques from SARS-CoV-2 Interestingly these authors were from different institutes as shown in Fig. 3 A and B. Furthermore, twenty-six countries have published atleast two research documents. Their interconnectivity is described in Fig. 4.
While, by three fields plot we also represented authors, institutes, and countries in the same diagram (Fig. 5).

Sources
The documents are published in 102 sources. The highest documents are published in Vaccines (n=8) and Nature Medicine (n=5). However, the highest citations were noted for New England Journal Of Medicine (n=838), followed by Morbidity And Mortality Weekly Report (n=66) and Nature (n=46). The list of top 20 sources with H-index, g-index and m-index details are described in table 2.

Co-words Analysis
Based on the co-words analysis it was noted that the publications focused on clinical trials (Phase 1, 2 and 3 Clinical Trial). Different subject groups were included (young to aged) in reports. The drug designing, safety, administration, dosage, side effects of bnt162b1 and bnt162b2 was explored for the possible treatment of COVID-19. The authors also analyzed various symptoms associated with COVID i.e. fatigue, fever, headache, inflammation, infection, injection site pain, and mortality (caused by). The genetic & immune response and epidemiology was also studied in detail. The co-words are described in Fig. 6 A &B.

Limitations
One of the major limitations of the present study is that we only explored Scopus. Other common databases, such as PubMed, Embase, and WoS, were not searched. Thus, some influential papers may have been missed. Therefore, future bibliometric studies with other databases are recommended which may complement the present findings. We also did not analyze letters, notes, editorials, conference papers etc. Most of the articles are recently published. Ample time is required to get proper citations. Consequently, it may affect the rankings of the manuscript (based on citations). Citation analysis may have spelling, names changes, homonyms, clerical errors, addition of post codes, language biases and problem with journal impact factors. However we did not consider it in the present report. Furthermore, we did not analyze self-citations, which may affect the total citation count.

CONCLUSION
There are various bibliometric reports about the COVID-19. To the best of our knowledge, this is the first study in which we summarized the publication histroy of the Pfizer-BioNTech vaccine. Initially, we discussed the advantages and disadvantage of bibliometric studies. Later some information about the novel therapeutics and vaccine development for COVID-19 is added. Based on the Scopus record, one hundred and seventy three (n=173) research documents (91 articles & 42 reviews) are published about Pfizer vaccine. Based on biblioshiny analysis, the local and global citation record is provided. We also briefly discussed the top five cited documents. 1160 authors have significantly contributed to all publications. The collaborative index (CI) was found to be 9.47. By Lotka's Law, we provided breif informaqtion about the frequency of publication of authors. For example, 1097 authors contributed to only one publication. Based on the number of publication, details about the top authors, university and country is provided. By Vosviewer analysis we presented the collaboration between authors, institutes, and countries. The documents are published in 102 sources. The citations details (h-index, g-index and m-index) of the top 20 sources are also provided. Last but not the least, the trend and focus of publication is depicted by co-words analysis.