Dengue research in India : A scientometric analysis of publications , 2003-12

Address for the correspondence: Dr. Mueen Ammed KK, Director, SciBiolMed.Org, No. 24, Bore Bank Cross Road, Harris Main Road, Benson Town, Bangalore, India E-mail: mueen.ahmed@gmail.com The present study quantitatively analyze Indian dengue research output during the 10 years from 2003 to 2012, using Scopus international multidisciplinary database. The study focused on global publication output, share, rank, and citation impact of top 15 most productive nations, India’s publications output, growth, global publication share and research impact, international collaborative papers share in national output and the share of major international collaborative partner countries in total India’s international collaborative papers, contribution of various sub-fi elds and distribution by population age groups, productivity and citation impact of its leading Indian institutions and authors and Indian contribution in most productive journals. Indian contribution in dengue fever research consisted of 910 papers, which increased from 27 papers in 2003 to 193 papers in 2012, witnessing an annual average growth rate of 28.19%.Among the top 15 most productive countries, India holds second position in dengue fever research output, with global publication share of 10.22% during 2003-12. The average citation per paper scored by India was 3.27, the least among the top 15 most productive countries during 2003-12. India’s share of international collaborative papers was 10.55% during 2003-12, which increased from 9.12% during 2003-07 to 11.13% during 2008-12. The present India’s research efforts in dengue research are low in view of the 50,222 cases of dengue in 2012 alone. The country needs to increase its research output and also increase its research impact substantially particularly through enhanced national and international collaboration, besides evolving a national policy for identifi cation, monitoring and control of dengue cases and also evolving a research strategy with suffi cient funding commitment to solve this growing national problem.


INTRODUCTION
Viruses are tiny agents that can infect a variety of living organisms, including bacteria, plants, and animals.Like other viruses, the dengue virus is a microscopic structure that can only replicate inside a host organism.The dengue viruses are members of the genus Flavivirus in the family Flaviviridae.Along with the dengue virus, this genus also includes a number of other viruses transmitted by mosquitoes and ticks that are responsible for human diseases.Flavivirus includes the yellow fever, West Nile, Japanese encephalitis, and tick-borne encephalitis viruses. [1]ngue fever (DF), also known as breakbone fever, is an infectious tropical disease, caused by the dengue virus.Symptoms include fever, headache, muscle and joint pains, and a characteristic skin rash (similar to measles).In smaller proportion of cases, the disease develops into the life threatening dengue hemorrhagic fever (DHF) resulting in bleeding low levels of blood platelets and blood plasma leakage, or into dengue shock syndrome (DSS), where dangerously low blood pressure occurs. [2]nternational Journal of Medicine and Public Health | Jan-Mar 2014 | Vol 4 | Issue 1 Dengue is transmitted between people by the mosquitoes Aedes aegypti and Aedes albopictus, which are found throughout the world.The Aedes aegypti mosquitoes are the primary vector of dengue.The virus is transmitted to humans through the bites of infected female mosquitoes.The Aedes aegypti mosquitoes live in urban habitats and breeds mostly in manmade containers.Unlike other mosquitoes Aedes aegypti is a day time feeder, its peak biting periods are early in the morning and in the evening before dusk.Aedes albopictus, a secondary dengue vector in Asia, has spread largely due to international trade in used tyres (a breeding habitat) and other goods (e.g., lucky bamboo). [3]e incidence of dengue has grown dramatically around the world in recent decade.Over 2.5 billion people -over 40% of the world's population -are now at risk from dengue.The incidence of dengue has increased 30-fold over the past 50 years.World Health Organization (WHO) currently estimates that they may be 50-100 million dengue infections worldwide every year.Before 1970, only nine countries have experienced severe dengue epidemics.The disease is now endemic in more than 100 countries.As estimated, 500,000 people with severe dengue are hospitalized each year, a large proportion of them are children.About 2.5% of those affected die. [3]veral southeast Asian countries are seeing record numbers of people infected with DF, a mosquito-borne virus for which there is currently no approved vaccine or specifi c drug treatment.Researchers from the University of Oxford and the Wellcome Trust estimated that 70% of the world's serious dengue cases are in Asia, with India alone accounting for 34% of the total. [4]e Directorate of National Vector Borne Disease Control Program (NVBDCP) is the central nodal agency for the prevention and control of vector borne diseases, that is, malaria, dengue, lymphatic fi lariasis, kala-azar, Japanese encephalitis, and chikungunya in India.It is one of the Technical Departments of Directorate General of Health Services, Government of India.There has been a surge in dengue cases in the country in 2012 when as many as 50,222 cases were reported against 18,860 in 2011.According to India's Health Minister, 28,292 cases were reported during the year 2010.He said in view of upsurge and geographical spread of dengue to newer areas, a mid-term plan has been developed by Government of India for prevention and control of dengue and many advisories have been issued from time to time to control and manage the outbreak of dengue in India.Field visits are carried out to assess the preparedness and to provide technical guidance to states.Training is also imparted to clinicians on case management as per Government of India guidelines and to other health care functionaries on program activities.For augmenting diagnostic facilities, the number of Sentinel Surveillance Hospitals (SSHs) with laboratory support has been increased to 347 across the country from 110 and linked with 14 apex referral laboratories with advanced diagnostic facilities for back up support for dengue across the country. [5]e Department of Biotechnology (DBT) of India has launched a program to promote and accelerate research activities in containing dengue disease and enhance the capacity and capability of those committed to dengue research.Establishment of dengue laboratory network program with defi ned gene amplifi cations for understanding the genotypes, serotypes, strengthening regional laboratories for rapid and confi rmatory diagnosis of suspected dengue cases, development of integrated companion diagnostic tests (Ag/Ab) and new rapid point of care diagnostic test systems and validation, and novel strategies for vaccine development has be promoted under the initiative.It will also enable utilization of primary human cell targets to understand the translational data on platelet, monocytes, DCs, and endothelial cells by using stem cell technology, studies on pathogenic antibodies in dengue hemorrhagic fever (their generation, specificity, regulation, seroepidemiology, etc.), development of advanced research program on platelet pathology and study on molecular markers of neurotropism and vector preference. [6]

Literature review
Few studies have been undertaken in the past on scientometric analysis of dengue research output.Dutt et al. [7] analysed 2566 papers on global research output in dengue, as covered in Science Citation Index (SCI)-Expanded from 1987 to 2008.The total output came from 74 countries of which 17 countries contributed 87% of the total output.The highest number of publications came from USA, followed by India.More than half of the scientifi c output is concentrated among four sub-disciplines of microbiology and virology, immunology and vaccine, epidemiology, and entomology.Among the prolifi c institutions, the publication output of institutions from the US and Taiwan had higher impact.About 80% of the papers appeared in journals originating from USA, the UK, the Netherlands, France, and Germany.Raja et al. [8] also analyzed world DF publication from 1999 to 2012, as covered in SCI database.The publications data is analyzed to know the authorship pattern, degree of collaboration and geographical distribution of papers, year-wise research output, geographical distribution of research output, and nature of collaboration, characteristics of highly productive institution and the channel of communication used by the scientists.
No paper has been published focusing on the analyses of Indian dengue research output till today.However, Gupta et al. analyzed bibliometric characteristics of Indian publications on several other diseases, such as typhoid, [9] diabetes, [10] tuberculosis, [11] malaria, [12] asthma, [13] HIV/AIDS, [14] and measles. [15]jectives of the study 3. To study the share of international collaboration in Indian publication output and the contribution of different collaborating countries; 4. To study the Indian contribution by sub-fi elds and by type of population groups; 5. To study the publication productivity and the impact of Indian leading institutions and authors; and 6.To study the media of communication

Materials and Methods
The study retrieved the publications data on India and top 15 most productive countries in dengue research from the Scopus database (http://www.scopus.com)for 10 years from 2003 to 2012.The keyword "dengue" was used in "title, abstract and keyword fi eld" along with India in "country fi eld" and "2003 to 2012" in time fi eld was used for searching the main publication data used in the study and this become the main search string.Similar strings were used to generate to generate publications output data on top 15 countries.For generating citation impact data, the 3, 2, 1, and zero years' citation window was used for publications during 2003-09, 2010, 2011, and 2012.For searching the international collaborative papers, a separate search strategy, which combines India's collaboration with more than 200 countries, was prepared and this string was combined with main search strategy string to generate India's total international collaborative papers and contribution of leading countries in India's collaborative papers.For analyzing institutional, author, and journals output, separate search strategies were developed, which later combined with the main search string to generate the desired output.

Analysis
The global publication share to top 15 most productive countries in dengue research varies from 2.38% to 25.26% during 2003-12.The USA tops the list with global publication share of 25.26%, followed far behind by India (10.22% share and second rank), Brazil (9.75% share and third rank), Thailand, UK, France, and Singapore (their global publication share ranging from 4.32% to 7.39% and rank from fourth to seventh), Australia, Taiwan, and Malaysia (their global publication share ranging from 3.02% to 3.81% and rank from eight to tenth ) and Japan, China, Cuba, Germany and Mexico (their global publication share ranging from 2.38% to 2.77% and rank from 12 th to 15 th ) during 2003-12 [Table 1].
Among the top 15 most productive countries, the publication rank has increased in France (from 6 th to 5 th ), Singapore (from 9 th to 7 th ), Malaysia (from 13 th to 9 th ), and China (from 15 th to 11 th ) as against decrease in UK (from 5 th to 6 th ), Australia (from 7 th to 8 th ), Taiwan (from 8 th to 10 th ), Japan (from 11 th to 12 th ), Cuba (from 12 th to 13 th ), Germany (from 10 th to 14 th ), and Mexico (from 14 th to 15 th ) from 2003-07 to 2008-12.During the same period, the publication rank has remained the same in USA, India, Brazil, and Thailand [Table 1].
In terms of research impact, the ranks have altered compared to ranks in publication productivity.The highest rank in terms of research impact among 15 most productive countries is occupied by UK with average citation per paper of 11.76 (with 5 th rank in   In all international collaborative papers of India, there may be one or more collaborating countries.As a result, the combined output of 15 foreign collaborating countries listed above in Indian international collaborative output will be more than its total international collaborative papers

Profi le of 15 productive Indian institutions in dengue research
The top 15 most productive Indian institutions involved in dengue research have published 14 or more papers each during 2003-12.
These 15 institutions involved in dengue research together have contributed 41.87% (381 papers) in the cumulative publications output of India in dengue research.The publication profi le of these 15 institutions along with their research output, citations received and h-index values are presented in Table 6.The average publication productivity per institution reported by the top 15 institutions was 25.4 and only 7 institutions have registered higher output than the group average.These are All India Institute of  TP = Total papers, TC = Total citations, ACPP = Average citation per paper, *There is some overlapping of papers under sub-fi elds.As a result, the combined output of India under seven sub-fi elds will be more than its actual total output

Profi le of top 15 most productive authors in dengue research
The top 15 most productive Indian authors involved in dengue research have published 12 or more papers each during 2003-12.
The publication profi le of these 15 authors along with their research output, citations received, and h-index values are presented in

Research communication in high productive journals
The 15 most productive journals publishing Indian research papers in dengue research together contributed 306 papers, which accounts for 33.63% share of the total output of India during 2003-12.The cumulative publications output share of these 15 most productive journals showed a decrease in India's publications output from 42.70% during 2003-07 to 29.87% during 2008-12 [Table 8].The severity of the dengue endemic in India is underestimated by lack of accurate information related to the incidence and cost of dengue illness.Furthermore, the manifestation of dengue in India appears to be changing from its benign form to its severe forms of DHF and DSS.This change is leading to an increase in the frequency of outbreaks, morbidity, and mortality.Dengue is a notifi able disease in India since 1996.However, misdiagnosis and underreporting of dengue cases persist due to clinical defi nition challenges, scarcity of diagnostic tools, and lack of healthcare providers' familiarity with dengue The huge hike in dengue cases is posing questions about the way India is going about its dengue prevention and control strategy aimed at source reduction.The government is now trying to rope in rural and urban local bodies for carrying out a special campaign for sanitation and cleanliness, fogging, increasing sentinel surveillance sites and training of health personnel.
Dengue mortality can be reduced by implementing early case detection and appropriate management of severe cases; reorienting health services to identify early cases and manage dengue outbreaks effectively; and training health personnel, along with appropriate referral systems, at primary health-care levels.Dengue morbidity can be reduced by implementing improved outbreak prediction and detection through coordinated epidemiological and entomological surveillance; promoting the principles of integrated vector management and deploying locally adapted vector control measures including effective urban and household water management.Effective communication can achieve behavioral outcomes that augment prevention programs.Research will continue to play an important role in reversing the trend in dengue, a neglected tropical disease, by improving methods and systems for surveillance, prevention, and control.
India urgently needs a permanent dengue surveillance system to monitor and control a mosquito-borne viral disease.Existing technologies such as geographical information systems, polymerase chain reaction, rapid antigen tests, genetic sequencing, and bioinformatics can be harnessed to provide a holistic approach to suppress dengue resurgence, in collaboration with the WHO's Dengue Net.Databases could be continuously updated and the reporting of dengue cases from India's existing network of institutions and laboratories standardized, with a view to predicting epidemics and reducing fatality rates.
India's research output is very low keeping in view of 50,222 cases of dengue in India in 2012 alone.Therefore, the country needs to increase its research output and also increase its research impact substantially particularly through enhanced national and international collaboration.
There is also need to evolve a national policy of identifi cation, monitoring, and control of dengue cases and also evolving a research strategy with suffi cient funding commitment and involvement of different type of Indian organizations to solve this growing national problem.

Table 1 : Publication output, share, rank and research impact of top 15 countries in dengue fever research, 2003-12 Name of country Number of papers Share of papers Rank of papers TC
38% share), Brazil (8.33% share), etc.It is observed that India's international collaboration has increased with Thailand by 14.08%, Malaysia by 12.68%, UK by 11.94%, Indonesia by 7.04%, Germany by 3.04%, and Vietnam (1.63%) in contrast to decrease in USA by 12.56%, Sri Lanka by 11.55%, France by 9.18%, Canada by 7.55%, Brazil by 4.96%, Philippines by 2.37%, Singapore by 0.96%, Switzerland by 0.73%, and Australia by 0.73% from 2003-07 to 2008-12 [Table 3].India's publication output in dengue research during 2003-12 has been published in the context of seven sub-fi elds (as refl ected in database classifi cation based on journal title subject), with highest publication India's contribution, citation impact, and international collaborationIndian contribution in DF research has increased from 27 papers in 2003 to 193 papers in 2012, witnessing an annual average growth rate of 28.19%.The average citation impact per paper registered by India's research in DF during 2003-12 was 3.27, which has decreased from 4.37 during 2003-07 to 2.79 during 2008-12.India has contributed 10.55% international collaborative papers share in DF research during 2003-12, which has increased from 9.12% during 2003-07 to 11.13% during 2008-12 [Table 2].

Table 5 : Dengue research output by population age group, 2003-012 Population group Number of papers Share of papers 2003-07 2008-12 2003-12 2003-07 2008-12 2003-12
, and Christian Medical College, Vellore (4.14).The average h-index value of these 15 Indian institutions was 6.53 and 7 Indian institutions have achieved higher h-index value than the group's average.These are Defence Research & Development Establishment, Gwalior with h-index value of 11, followed by National Institute of Virology, Pune(10), International Centre for Genetics & Biotechnology, New Delhi(10), All India Institute of Medical Sciences, New Delhi (8), C S Medical University(8), Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow(7), and National Institute of Communicable Diseases, Delhi(7).
International Journal of Medicine and Public Health | Jan-Mar 2014 | Vol 4 | Issue 1

Table 7 .
These 15 authors involved in dengue research together have contributed 32.75% (298 papers) in the cumulative publications output of India in dengue research during 2003-12.

Table 7 : Productivity and citation impact of 15 most productive authors in dengue research, 2003-12 Name of the author Address of the author TP
International Journal of Medicine and Public Health | Jan-Mar 2014 | Vol 4 | Issue 1 86% share).Among different population age groups, the largest focus of research on dengue was on adults (with 28.35% share), followed by child (21.43% share), adolescents (19.78% share), middle-aged (10.99% share) and aged (6.59% share) during 2003-12.Among the Indian institutions contributing to dengue research, only 15 have published 14 or more papers each during 2003-12 and together have contributed 41.87% publication share to the cumulative publications output of India in dengue research.The average citation per paper and h-index registered by the total papers of these 15 institutions was 3.69 and 6.53, respectively, during 2003-12.Among the Indian authors contributing to dengue research, only 15 have published 14 or more papers each during 2003-12 and together have contributed 32.75% share to the cumulative publications output of India in dengue research.The average citation per paper and h-index registered by the total papers of these 15 authors was 5.33 and 6.87, respectively, during 2003-12.Among various journals publishing Indian dengue research papers, the top 15 journals have contributed 33.63% share of the total output of India during 2003-12, which has decreased from 42.70% to 29.87% from 2003-07 to 2008-12.

Table 8 : Media of communication of indian scientists in most productive journals in dengue research, 2003-12 Name of journal Number of papers 2003-07 2008-12 2003-12
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