Online Communication as a Potential Travel Medicine Research Tool: Analysis of Messages Posted on the TravelMed Listserv

Liane Macdonald MD, Douglas W. MacPherson MD, MSc(CTM), FRCPC, Brian D. Gushulak MD
DOI: 7-12 First published online: 1 January 2009


Background Access to the Internet and electronic mail has created opportunities for online discussion that can facilitate medical education and clinical problem solving. Research into the use of these information technologies is increasing and the analysis of these tools can support and guide the activities of professional organizations, including educational endeavors.

Objective The initial objective was to analyze patterns of information exchange on the International Society of Travel Medicine’s (ISTM) travel health electronic mailing list related to a specific area of society interest. Secondary objectives included the analysis of listserv use in relation to subscriber demographics and rates of participation to support travel health educational activities.

Methods This study examined the use of the ISTM TravelMed listserv over an 8‐month period from January 1, 2006, to July 31, 2006. Descriptive data analysis included TravelMed user demographics, the type of posting, the topic and frequency of postings, and the source of information provided.

Results During the study period, 911 (47%) of the eligible ISTM members subscribed to the TravelMed listserv. About 369 of these subscribers posted 1,710 individual messages. About 1,506 (88%) postings were educational; 207 (12%) postings were administrative. A total of 389 (26%) of the educational postings were primary queries and 1,120 (74%) were responses, with a mean string length of 2.9 responses per query (range: 1–51). Twenty participants contributed 40% of the educational postings. The topics with the most frequent postings were vaccines and vaccine‐preventable diseases (473/31%) and malaria (258/17%). Postings focused on special populations, including pregnant women or immigrants, comprised a total of 14 postings (<1%).

Conclusions During the study period, a limited number of ISTM members (19%) authored postings on the listserv. Regular discussion centered on a limited number of recurring topics. The analysis provides several opportunities for the support of educational initiatives, clinical problem solving, and program evaluation.

As the accessibility of Internet‐enabled electronic communication expanded in the 1980s, the rapid and simultaneous distribution of information to multiple recipients became both feasible and uncomplicated. The use of electronic mailing lists to link large numbers of individuals who share particular interests is now common in scientific and nonscientific spheres alike. Early electronic mailing lists were manually administered, but since the introduction of automated programs in the mid‐1980s, listserv capacities have increased. 1 The expanding use of the Internet and electronic communication has created opportunities for online information exchange that can facilitate medical education and clinical problem solving. 2 Additionally, during the past decade, studies have explored potential roles of this technology for Internet‐based communication between providers and patients. 3 As use of these e‐health tools grows, research into health care professionals’ use of these information and communication technologies is also increasing. 4 This study used the analysis of the electronic mailing list of the International Society of Travel Medicine (ISTM), the TravelMed listserv, to describe and compare interest in particular aspects of the society’s activities.

The nature of the practice of modern travel medicine and the scope of activities of the ISTM are broad. 5 Determining the relative level of interest in one aspect of the society’s activities, the area of refugee and migrant health, has been a long‐standing interest of the ISTM committee that is mandated to address this issue. This study was initially designed and proposed to examine the number, frequency, and character of messages on the TravelMed listserv specific to refugees or migrants, and to quantitatively relate that information to listserv messages pertaining to other subjects.

As the study progressed, it became apparent to the investigators that the information and resulting analysis, while addressing aspects of the initial question, could also provide useful insight for the society executive and management and the membership as a whole.


This study examined the use of the ISTM TravelMed listserv over an 8‐month period from January 1, 2006, to July 31, 2006.

The listserv was founded by the society’s Electronic Communications Committee in 1995 and has functioned continuously since that time. It is an unmoderated electronic discussion forum supported by the volunteer service of society members. TravelMed automatically and in real time disseminates postings, comments, and replies to all subscribers. At the time of the study, the listserv operated on Listserv® 14.5 software.

Participation in TravelMed is open to all members of the ISTM and subscription to the listserv is integrated with the society’s membership renewal processes. Postings are archived and the ISTM provides members with access to these archives. Information regarding subscription and use of the TravelMed listserv can be found at the society’s Web site (

A sequential prospective approach was used to better assist in tracking the linear relationship of threads generated from specific postings. Postings, many of which are generated by patient consultation, may evolve through subsequent discussion and member comment. Relating linkages by message title using the aggregated message repository was more complicated and time consuming than sequentially following the e‐mail traffic. Permission to collect and analyze the TravelMed postings was sought and obtained from the ISTM executive. A single observer (B. D. G.) gathered and classified each posting on the mailing list during the study period. Messages were recorded according to the date and time (coordinated universal time minus 1 h) they were received by the cataloging observer. Messages were first classified as either queries or responses. The content of each message, rather than its format, determined its categorization as query or response. Any reply containing a new question or query was also classified as both a query and a response. All messages were then collated according to a series of 27 primary and 201 secondary topics.

Message authors were coded according to geographic location, professional qualification, and the indication as to whether or not their listing on the ISTM Web site indicated that they had received their ISTM Certificate of Knowledge in Travel Medicine (CTH®).

Messages dealing with the functioning of the society, the operation of the listserv, absences from the office, or duplicate messages were classified as administrative. Those related to clinical situations, health, and disease including geographic aspects of health were considered educational. When a message contained information about travel health practice or education, it was further coded as opinion, opinion supported by described clinical or educational experience or information supported by reference material, either online or published.

Study authors conducted a literature search to anticipate the unique ethical challenges of research involving online communities, including listservs. Data extraction, analysis, and reporting methods proved ethically consistent with the current recommendations of the relevant Internet research ethics literature.


Use of the TravelMed listserv during the study period

During the study period, 1,710 messages were received and coded for analysis. At that time, the ISTM had 1,935 members, 911 (47%) of whom subscribed to TravelMed (ISTM Secretariat, personal communication, 2006).

A total of 1,506 (88%) of the messages were classified as educational. The remaining 204 (12%) were administrative in nature. Of the 1,506 messages classified as educational postings, 389 (26%) were primary queries. The remaining 1,120 (74 %) were postings in response to primary query. Analysis by query indicated that each original query elicited a mean string of 2.9 responses. The number of responses per query ranged from 1 to 51. The mode was a single response (Table 1).

View this table:
Table 1

Educational TravelMed listserv postings, from January 1, 2006, to July 31, 2006

TotalPrimary question/commentReply
Total1,506 (100%)389 (26%)1,120 (74%)
20 most frequent users662 (43% of total)157 (40% of questions)495 (44% of replies)
10 most frequent users448 (30% of total)100 (26% of questions)348 (31% of replies)

User demographics

During the study period, 369 members, representing 19% of the total society membership and 41% of the TravelMed listserv subscribers, posted at least one message.

Most subscribers submitted a self‐report of their professional status. Of these, 252 (68%) were physicians and 80 (22%) identified themselves as members of the nursing profession. The professional status of others posting messages included pharmacists, paramedics, nurse practitioners, medical assistants, and paraprofessionals. The professional status of 6% (21) of users was unknown.

Twenty‐six percent of all subscribers during the study period had indicated that they had obtained their ISTM CTH. 6 Seventy percent did not have ISTM certification. The ISTM certification status of 4% of users was unknown. In comparison, 18% of the 1,935 ISTM members in 2006 were reported as having the ISTM certificate.

The geographic location of subscribers posting messages during the study period revealed that the majority of users resided in North America. Sixty‐five percent of the educational postings originated in Canada and the United States. European subscribers contributed 18% of educational postings. Of the remaining postings, 6% originated in Oceania, 5% in Asia, 2% in Africa and the Middle East, 1% in South America, 1% in an unknown region, and less than 1% in the Caribbean.

Review of the geographic distribution of the general membership of the society in 2006 indicated that 1,198 or 62% of members resided in North America, while 450 or 23% were located in Europe.

Initial messages

About 389 or 26% of educational messages dealt with new queries or topics. These initial questions and original comments originated from 169 (46 %) of the 369 ISTM listserv participants who posted messages during the study period. Subscribers identified as physicians posted 68% of such messages. Those identified as nurses posted 27%. During the study period, 40% of those who posted queries reported that they had successfully obtained their ISTM CTH. Physicians who posted initial queries were more than twice as likely as nurses who posted queries to possess ISTM certification (38% of physicians vs 18% of nurses).

The mean number of primary questions or comments per individual user was 1.05, with a range of 0 to 13, and a mode of 0. Twenty users generated 40% of primary questions or commentary postings. Ten individual subscribers contributed 26% of primary postings.

Responses to initial messages

About 1,120 responses to original questions or comments were posted. Of those, three both responded to a query and raised a new query [as such, they were counted in both categories, but only once in the total number of postings, accounting for the discrepancy between the sum of queries and responses (1,509), and the total number of responses (1,506)].

About 262 (70%) of the TravelMed listserv subscribers replied to a question or comment. The mean number of replies per individual subscribers was three replies, with a range of 0 to 62. Ten individuals accounted for 31% of all replies and the 20 most frequent responders generated 44% of all replies. Physicians posted the majority (82%) of replies, while nurses accounted for 14% of messages coded as replies. Similar rates of ISTM certification characterized those who replied to questions, with 56% of repliers not indicating CTH certification. Similar to the situation observed in the original query/comment group, physicians replying to a message were more likely than nurses to have CTH certification (41% vs 23%).

Topics of queries on the TravelMed listserv

When messages were coded into 1 of 27 primary classifications (see Table 2), 7 of these topic clusters (Table 3) represented 83% of all postings. The topic that generated the longest response string with 51 postings during the study related to the use of the society’s Web site for providing expert opinion. The second longest message string (24 postings) was generated by a question regarding tungiasis in a returned traveler. Two aspects associated with the provision of travel medicine services, the reimbursement and billing for the provision of advice and managing requests by patients for the administration of vaccines only, generated strings of 15 and 14 messages, respectively. Questions and discussion regarding the side effects of antimalarial medication (15 postings) and methods of cleaning raw fruits and vegetables (14 postings) made up the other long discussion threads.

View this table:
Table 2

Primary posting classification of TravelMed, from January 1, 2006, to July 31, 2006

Primary topicPostings (%)
Administrative (International Society of Travel Medicine)15
Air travel1
Business of travel medicine4
Complex cases2
Human immunodeficiency virus1
Japanese encephalitis1
Local provider search4
Medication/drug availability1
Migrants or refugees1
Prevention during travel7
Returned travelers3
Tick‐borne disease>1
Travelers diarrhea1
Women travelers1
View this table:
Table 3

Aggregate topics of primary queries on TravelMed, from January 1, 2006 to July 31, 2006

Message topic groupPercentage of messages
Vaccine‐preventable diseases/vaccines37
Vector‐borne diseases (malaria, etc)22
Environmental issues (altitude, heat, etc)4
Special populations (pregnant women, migrants)3
Human immunodeficiency virus/tuberculosis3
Water exposure issues (sewage, etc)2
Ingestion issues (food and beverage associated)1

Vaccine‐preventable diseases (VPDs), including vaccines themselves, predominated in the content of 37% (143) of all original questions or comments. VPDs that generated the most original queries or comments included yellow fever (11%), Japanese encephalitis (6%), and rabies (5%). Messages related to vector‐associated diseases accounted for a further 22% of original questions or comments. Malaria was the single most frequent topic of original questions or comments on the listserv (n = 74, or 19%).

Questions and comments belonging to the “General” category in the ISTM Body of Knowledge for the Practice of Travel Medicine constituted the next largest cluster, producing 16% (n = 62) of the original questions or comments. This included messages related to obtaining medical providers during travel (8%), formal travel medicine education information (6%), and the business aspects of travel medicine (3%).

Pretravel concerns informed the primary topic of 12% (n = 48) of original questions or comments. Queries or observations specific to pretravel preventive measures or counseling provided 5% of all original questions or comments, while 3% represented requests for help with complex pretravel case consultations. Altitude was the primary topic of 4% of questions or comments, while other diseases associated with environmental exposure to water (including sewage exposure, leptospirosis, and schistosomiasis) were the focus of 2% of original questions or comments.

Human immunodeficiency virus and tuberculosis accounted for 1 and 2% of the primary topics, respectively. Population‐centered primary topics—including refugees, migrants, pregnancy, females, or returned travelers—characterized only 3% of the original questions or comments. Postings dealing with migrants or refugees, the major interest of the study, numbered 14 in total, less than 1% of all messages analyzed. This information is summarized in Table 2.

Sources of information for replies

The replies contained various types of response, including opinion or experience alone, opinion supported by evidence, information with citation of evidence, or other combinations with published or online reference materials. About 261 (23%) of 1,120 replies contained information from or links to published or online reference material.


The nature of the use of electronic mail lists limits the analysis of postings to those who complete and send messages. ISTM members may demonstrate their travel medicine interests through a variety of activities; this study design cannot capture the interests that ISTM members express via other fora and it cannot describe the interests of ISTM members who do not subscribe to TravelMed. This study design also cannot estimate or quantify the interests of subscribers who may have used TravelMed and not posted a message, 7 or who responded directly back to the poster of the query.

Additionally, the study reflects message postings for only an 8‐month period of time during which new members of the society joined and withdrew from the electronic mailing list. Long‐term fluctuations in either posting volume or message topic would not be apparent through this study. More sustained study over longer time periods limited to members and subscribers who participating over the entire observation period could eliminate the effects and impact of novice users and subscriber withdrawal. Similarly, a retrospective analysis of the archived TravelMed postings since 1995 could also address variations not detected by a time‐limited analysis.


The analysis revealed that the members of the TravelMed listserv rarely discussed postings related to the study’s original area of interest, refugee and migrant health issues. There are several potential reasons for this observation. Many of the TravelMed postings are generated by client or patient contact and the majority of listserv subscribers may see limited numbers of such clients or patients. Second, listserv users who do encounter refugee or migrant clients or patients may direct their queries to other venues.

This information may be useful to the Refugee and Migrant Health Committee of the ISTM as that group determines the most appropriate venues for its work. The relatively infrequent listserv postings pertaining specifically to refugee and immigrant populations in this analysis suggest that other topics may have more relevance to ISTM members. As such, the committee may wish to consider expanding its efforts beyond the tools serving the current ISTM membership. Additionally, the committee may wish to consider the use of the listserv for distribution of interesting cases or migrant‐relevant information rather than waiting for the generation of questions on TravelMed.

Beyond the primary study question, however, the study does provide insight into the use and nature of the TravelMed electronic mailing list that may be of use to the society as a whole. Health care providers are examining the roles of modern communications technology in improving information exchange and patient care. 8 These tools can be beneficial to organizations with large, widely dispersed memberships.

During the study period, TravelMed was frequently used by a limited number of ISTM listserv members who used the forum to undertake regular discussion. Issues and message threads dealing with a relatively limited number of topics recurred repeatedly during the study period. Those most frequently raised were related to vaccines and VPDs and malaria (Figure 1). Recurring items of interest related to VPDs included yellow fever, Japanese encephalitis, and rabies. This recurrent interest in particular topics, several of which are emphasized in the ISTM Body of Knowledge, 9 suggests that the analysis of TravelMed utilization and topics could assist and facilitate the design and content of continuing medical education (CME) activities for the society.

Figure 1

Number of postings by topic. ISTM = International Society of Travel Medicine.

Due to the original focus of this study, it was limited in time and subject to temporal variations in topics and volume of postings. Extended analysis of this type could perhaps be anticipated to other patterns of use not present during the study period. Longitudinal analysis could reveal cyclic or seasonal patterns of postings related to travel destinations frequented by tourists, recurrent health risks, and seasonal patterns in the use of vaccines and/or medications. The identification of such patterns could support the timed release or publication of reviews, recommendations, or educational material that would coincide with increased readership interest. Additionally, similar studies of longer duration could provide insight into the impact of disease outbreaks or epidemics of travel medicine–related disease on TravelMed postings. During the study period, for example, there was an outbreak of chikungunya virus infection that would subsequently have implications for travelers. 10 Two postings dealing with chikungunya and pregnancy noted in the study that longer term analysis may have provided insight into the broader reporting and travel medicine implications resulting from the event.

This analysis and more in‐depth ongoing evaluation of the topics and content of TravelMed may also indicate topics and areas of subject knowledge interest that would be useful to the society membership. This information could be used to select topics for review in the professional journal, online reference material, at conference meetings and symposia, as well as for targeted educational communication and reference material. The recurrence of traffic on specific topics or threads could be used as a trigger for reminder messages or the distribution of links to reference material, case studies, and expert opinion already prepared by the society or other organizations. On a broader perspective, the nature of the listserv and its use by culturally and linguistically diverse members of the society may also be reflected in the participation in this venue or the use of other venues for information sharing and education related to travel medicine.

Additionally, more involved and detailed analysis of TravelMed utilization in relation to subscriber characteristics, particularly in terms of ISTM certification, may provide a venue for feedback evaluation of the ISTM certification process and demonstrate the importance of certification as an educational component that facilitates the practice of travel medicine. There were, for example, suggestions that increased education in travel medicine was associated with increased use of the listserv. During the study period, 26% of those using TravelMed had indication of having received the ISTM certification in travel medicine. During the time of the survey, 18% of the general membership had acquired certification.

The demonstrated patterns of use of the TravelMed listserv suggest existing limits in both content and participation that merit future exploration. More detailed analysis of the distribution and generation of posting by physicians and nurses could, with relational surveys of practice dynamics, reveal greater insights into professional educational needs and the ISTM’s response to these needs. This information could assist in the better understanding of the differences in the provision of travel medicine services across and between nations. As noted above, analysis of this type only accounts for those who actively post messages to a mailing list. The impact on those who receive and make use of the information passively is unknown. Such information is important to ensure that expanded use of electronic educational material does not isolate significant numbers of those involved who do use these systems. 11

The results represented in this study also provide a basis from which the organized distribution of CME information, guidelines, or normative standards released through the electronic mailing list can be evaluated. The impact of clinical reviews, case studies, and other reference material could be evaluated over time by examining the frequency and nature of postings before and following their release. Disparities in TravelMed use by profession and location revealed by this and subsequent evaluation can provide information for the society that may be useful and important in increasing outreach. The results may be used to guide and support initiatives to increase the role of the ISTM and design additional tools and reference material that furthers the society’s goals. More detailed user analysis may help better define the characteristics of those who use the service. 12 The roles of undergraduate medical, nursing, and other health professional training programs; technological skill; and concerns about the Internet’s impact on workload, income, or liability may influence who chooses to participate in TravelMed.

Finally, from an academic perspective, this study reveals opportunities for the development of empirical standards and guidelines to provide standard reference sources for items of frequent or sustained interest. 13 Over time, such activity could increase the scientific basis of the practice of travel medicine.

Declaration of interests

The authors state that they have no conflicts of interest.


  • Preliminary findings of the study were elements of a poster session by the same authors that was accepted and presented at CISTM 10 in Vancouver in May 2007.


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