Participants were chosen through Twitter’s search function using the terms “public health practitioner,” “MPH” (master’s in public health), “public health,” and “APHA” (American Public Health Association). After individuals were identified as public health professionals, participants were chosen based on a set of inclusion and exclusion criteria. Inclusion criteria were as follows: the individual was a public health professional and had to have a minimum of 300 followers. Exclusion criteria were as follows: the individual could not be a part of an academic institution, and it could not be an organization’s Twitter page (eg, CDC, local health departments, and NIH). Overall, 220 public health professionals were chosen to examine their tweets during a 6-month period from October 1, 2014 to March 31, 2015. A total of 15,236 tweets were collected and then analyzed using the constant comparison method.

The constant comparison method was used to analyze the tweets to reduce the data into manageable units and coded information [14-16]. The process began with open coding, which can be defined as “the process of breaking down, examining, comparing, conceptualizing, and categorizing data,” where 2 trained researchers (NS and MH) open-coded all the tweets and discovered major themes [14-16]. The tweets were then selectively coded into those major themes by the same 2 trained researchers (MH and NS; [14-16]). Open coding was done by hand versus using keyword searches through data mining software to take on the full context of the tweets/posts.

Informing and education tweets centered around informing and educating the public on various aspects and updates in public health. Within the theme, there were seven major topic areas covered: Ebola; human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS); Affordable Care Act (ACA)/health care; health law and policy; emergency/emergency preparedness; environmental health factors; and health and nutrition (Textbox 1). During the 6-month period of tweets collected, panic about Ebola was prevalent, and many public health professionals tweeted information to dispel panic and myths (see Figure 1).

Another area where public health professionals tweeted information to dispel misinformation was about the ACA (see Figure 2).

Although social media has drastically changed the way of communication, it has also created a way to spread misinformation quickly. As public health professionals have the credentials/authority tied with their Twitter accounts, they can dispel misinformation as well as spread other important health information to the public at a rapid rate.

Tweets identified as monitoring health status and trends were not using surveillance techniques, instead they were informing the public of updates on specific health statuses and trends (see Figures 3 and 4). Within the theme, there were seven major topic areas covered: HIV/AIDS; health and nutrition; influenza; smoking/tobacco/marijuana; technology/innovation; infectious diseases; and noninfectious diseases (Textbox 1).

Through the word limit function in Twitter, public health professionals are forced to condense important information into 140 characters, making these important updates on specific health statuses and trends more relatable to the lay population.

Social justice tweets focused on raising awareness and support for various public health issues (see Figures 5 and 6). Within the theme, there were seven major topic areas covered: global poverty/homelessness; global famine/water; charity/organizations/APHA; education and literacy; mental health; violence/safety/social justice; and non-public health–related (Textbox 1).

Twitter provides a space for public health professionals to share items they are passionate about, within or outside, their field. This platform also allows them to connect and collaborate with other professionals who are interested in the same social justice issues.

Professional development occurred when health professionals tweeted new public health information obtained at conferences and forums, as well as with the exchange of sources of scientific literature back and forth between other public health professionals and the general public (see Figures 7 and 8). This particular theme contained only one tweet category: conference/forum/APHA (Textbox 1).

Twitter provides a unique platform for professional development as budget cuts decrease the opportunity to connect and collaborate with other public health professionals.

Similar to public health organizations, public health professionals are also using Twitter to inform and educate the public. These results are not surprising, as one of the main tenets of public health is to “educate and inform” [7]. This information and education on social media is crucial, as Twitter’s main users (aged 18 to 29 years), do not obtain “news” from regular media (newspapers, magazines, and television) but from social media [17]. As social media has become a main resource of knowledge for many, so has misinformation. With the credibility seen in microblogging, it is important for public health professionals with credentials/authority to dispel this misinformation among the public [6]. The results show public health professionals attempting to combat misinformation on Ebola.

Public health organizations use Twitter to monitor health status and trends through syndromic surveillance [7,11,12]. However, public health professionals were not using surveillance techniques, they were informing the public about updates on specific health statuses and trends. This also allows public health professionals to take technical research and translate it into 140 characters, or lay terms, for the public to understand and disseminate among their social groups. These tweets may also contain embedded links, which then lead individuals to health department websites or other credible websites where they might not have gone to in the first place [7]. The nature of Twitter also provides the public with a way to ask questions directly, allowing public health professionals to provide information they may not have otherwise [7].

The most visible tenet of public health is the concept of social justice [18]. The concept of social justice stems directly from public health’s mission to “protect and promote health of the population as a whole” [18]. Results mirror this founding ethical principle and show that public health professionals are passionate about many health inequalities. Twitter also allows these same professionals a way to connect with other professionals, within and outside public health, who are also advocating for the same issues.

Finally, akin to public health organizations, public health professionals are also using Twitter as a means of professional development. Over the years, many states have seen significant decreases in funding for public health, severely limiting resources available to the public as well as to the public health professionals (eg, continuing education and conferences). Twitter provides public health professionals with a unique platform, to still engage with local conferences, as individuals attending tweet about sessions while they are occurring. Twitter also provides a way for public health professionals to connect and collaborate with other public health professionals in real time, despite being limited in funding for travel.

The scope of the tweets examined was during a 6-month window and was limited to that specific time frame. Although limited throughout the 6 months, the tweets reached saturation before 6 months, ensuring that tweets collected were representative of public health professionals’ Twitter activity. A second limitation was that the individuals analyzed only had to have a minimum of 300 followers. Although this is a small number of followers, because public health professionals are early adopters, they will not have a large following yet. The final limitation was that the category “non-public health–related” was the most common tweet category. Looking at the categories as a whole makes it appear that public health professionals are not talking about public health the majority of the time, but when one looks at the tweets (see Table 1) as two categories—non-public health and public health—11,204 tweets were on various public health topics, and only 4032 were non-public health–related.

For more adoption to occur among public health professionals, public health organizations should consider removing social media filters, specifically from Twitter. The removal of social media filters would eliminate the barrier of public health professionals only being able to tweet during after work hours, thereby encouraging increased adoption of the social media platform among public health professionals as well as enabling them to rapidly spread critical health information to the public as it occurs “in real time.” Unlike the majority of health organizations, public health professionals’ individual Twitter accounts outside organizations are not monitored by the government, and they are able to disseminate important information to colleagues and the lay population, such as how climate change affects public health, that organizations may not be able to disseminate, despite how critical that information is to the overall public health in the United States.