What doctors say about Zika virus

A year after Zika virus was confirmed in the Americas, Daniel Ghinn reviews HCP reactions on social media and assesses their interactions as news about the outbreak has developed over subsequent months.

This month marks one year since lab tests in Brazil confirmed that the mosquito-borne Zika virus had arrived in the Americas for the first time, sparking fears of a new global disease outbreak. In the time since then, the disease has spread explosively, according to the World Health Organisation (WHO), and has now been detected in nearly every country or territory infested with Aedes aegypti, the principal mosquito species that transmits Zika, dengue, and chikungunya.

During an emerging health crisis it can be helpful to understand what healthcare professionals (HCPs) are saying, distilling their voices on social media, for example, from all the other public and media noise. Analysis of online HCP conversations about Zika virus over the last 12 months shows how doctors and other HCPs around the world have been reacting to news about the virus, and how and where they have been learning about it.

Playing down the impact

Throughout 2015, HCP conversation about Zika virus outside of South America was limited. Our analysis suggests that most HCPs were not particularly alarmed about Zika when it first reached the Americas, with some even referring to the virus as 'dengue-lite', playing down its potential impact when compared with the debilitating mosquito-borne tropical disease dengue fever.

During this period, key events in the spread of Zika virus were annotated by doctors sharing information in affected countries; Zika's detection in Colombia in October was marked by a spike in HCP conversations in the country, as well as in the US where some doctors were watching developments.

Figure 1. During the first six months after Zika virus was detected in Brazil, the 10 countries where HCPs talked about the disease the most were predominantly in the Americas, although interest was very limited aside from discussions about significant news events. (Source: Creation Pinpoint)

Raising the alarm

One doctor in Brazil, however, was far from complacent during the early days of the Zika virus outbreak. Daniela Freitas, a professor at the University of Piauí with a special interest in microbiology, immunology and parasitology, was one of the most prolific HCPs discussing the virus, posting well over 2,000 tweets about Zika in the 12 months since May 2015. During the early days of the outbreak, she tweeted in Portuguese, sharing resources, warnings and information about the spread of the disease, such as PAHO's interim recommendations for detection and diagnosis on 24 June.

When Brazil reported that it had the virus on 7 May, Prof Freitas had shared four posts about Zika, and from this day on it appears she was on a quest to learn and share information about the virus. Her ongoing commentary cited the New England Journal of Medicine; the US Centers for Disease Control (CDC) and WHO, as well as politicians and writers.

Largely apathetic

Towards the end of 2015, as more countries in the Americas reported Zika virus, there was a gradual increase in HCP conversation about it. At this stage the HCP reaction to the virus was still largely apathetic, even when WHO issued an alert on 1 December about an association between Zika virus and congenital malformations in the Americas.

Figure 2. HCP conversation about Zika virus increased towards the end of 2015 but remained low volume even after WHO's congenital malformations warning. (Source: Creation Pinpoint)

In terms of HCP conversation, 2015 may be seen as the calm before the storm for Zika virus, with low HCP interest in sharing news and resources on the disease until early 2016. On 4 January 2016 doctors shared a Tweet posted by The Lancet Infectious Diseases journal, referring to Zika virus somewhat light-heartedly as 'the disease du jour'. But over the following hours and days a series of new reports from Brazil brought the tragic effects of Zika virus into the limelight.

On 5 January researchers reported the first diagnoses of intrauterine transmission of the Zika virus in two pregnant women in Brazil whose foetuses were diagnosed with microcephaly, including severe brain abnormalities. Throughout January, new reports confirmed cases of Zika virus associated with microcephaly, a condition in which babies are born with an abnormally small head and impaired brain development. As reports of the effects of the disease increased, so did HCPs' levels of interest and conversation.

Figure 3. In 2016, HCP online conversations exploded as WHO and CDC issued alerts and guidelines. (Source: Creation Pinpoint)

By the end of January, as the WHO warned that cases of Zika virus were 'spreading explosively', HCP conversation about the topic was fuelled by further news reports of the disease appearing in more countries, including the US. In the UK, midwives used Twitter to share advice in a briefing from the Royal College of Midwives. Some doctors, however, such as Prof Marion Koopmans, head of virology of the Laboratory for Infectious Diseases of the National Institute of Public health in the Netherlands, expressed concern that the conversation taking place about microcephaly was based on information from popular media, rather than peer-reviewed reports.

On 1 February, when the WHO declared that the association of Zika infection with microcephaly and other neurological disorders constituted a Public Health Emergency of International Concern – placing it in the same category of emergency as the 2014 Ebola outbreak – HCPs' interest in the disease peaked, reaching more than 5,000 mentions worldwide on one day.

HCP sources

As the Zika virus story has developed, doctors who were widely complacent about the disease during the initial months of the outbreak became increasingly interested in learning and sharing information. Despite some comments from HCPs about the lack of scientific content available at first – and therefore the risk of being led by popular media stories – it is perhaps reassuring to learn that the authorities HCPs were most likely to share information from included the world's major public health authorities – WHO and CDC, as well as their peers and medical journals. In fact, the Twitter profile most mentioned by HCPs in relation to Zika virus was @WHO (3.4% of all HCP Tweets about Zika virus mentioned or cited @WHO), followed by @CDCgov (2.6%).

What can we learn?

Studying the development of HCP online conversations about Zika virus, with the benefit of hindsight, illustrates some interesting behaviours. Here are my key learnings:

1. Even if many doctors are unmoved by an emerging issue, there may be some with a special interest, like Prof Freitas, who work hard to raise its profile. Throughout the Zika virus outbreak, her tweets have provided a rich resource for peers and the public.
2. During a public health crisis, doctors look to leading authorities like WHO and CDC, medical journals and their own peers for authoritative content and direction, and overall appear to trust them more than the popular media.
3. Although social media provides doctors with a platform for international collaboration, most are primarily concerned with issues that are likely to affect them, as shown by spikes in local HCP conversations following reports of Zika virus appearing in new countries.

Data for this article was analysed using Creation Pinpoint, the HCP online insights platform. A total of 129,914 HCP posts on public social media during a one-year period between May 2015 and April 2016 were studied, including Tweets, forum posts, comments and blog posts.

About the author:

Daniel Ghinn is Founder and CEO of Creation Healthcare, the HCP online insights consultancy and inventor of Creation Pinpoint. He tweets at @creationdaniel.