PNG COVID research offers insight into vaccination levers for the hesitant

A research survey conducted in PNG at the height of the COVID-19 crisis has cast light on the difficulty of getting health messages across to people in developing countries.

Data for health care interventions in PNG are notoriously unreliable, but the WHO says that in Papua New Guinea – a country of 9.1 million people – there have been 45,819 confirmed cases of COVID-19 with 668 deaths. As of 29 October 2022, a total of 494,272 vaccine doses have been administered.

The COVID-19 Vaccination tracker reported that up to July this year less than 4% of PNG people had been vaccinated.

“Addressing vaccine hesitancy in developing countries”, a research report published in PLOS ONE, gives some hope on ways of improving this.

Chief among the findings was that about half of all people could have their minds changed about their intentions to vaccinate if they were encouraged to do so by health care workers. The other two groups of influence were families and church leaders.

Almost no other group of influencers — such as teachers, political leaders, high profile athletes — was mentioned in any substantial way.

Conducting surveys in developing countries is beset by difficulties. In PNG the phone system is not universal; phone use seems to be dominated by males, and there is no widespread media penetration. However it is estimated that 20% of the adult population uses Facebook.

The phone survey revealed very high levels of vaccine hesitancy in PNG. Only a small minority (18%) of Papua New Guineans who had heard a vaccine was available were planning on being vaccinated. Most respondents stated they were unwilling to be, or not sure about being, vaccinated against COVID-19.

People said they were worried about the side effects of the COVID-19 vaccine. The second most common response was low trust in the vaccine.

The survey data shows that respondents who trusted the vaccine and who believed that their family and friends would be vaccinated were much more likely to be willing to get the vaccine.

But, although vaccine hesitancy was high, the survey suggested people might be amenable to having their views changed. Respondents that did not plan on being vaccinated or were unsure were asked, “Would you be more likely to receive the COVID-19 vaccine if any of the following individuals/authorities receive or recommend the vaccine?”

While 34% of respondents stated that “no one could change their mind”, 48% of respondents said that recommendations from health workers would make them more likely to be vaccinated. In addition, phone survey respondents were asked their most preferred way of receiving information about the vaccine and the vast majority of respondents (77%) stated face-to-face communication from health workers.

Key messages for policy-makers

“Our study highlights three key areas for policymakers to prioritise as they attempt to reduce vaccine hesitancy,” the researchers wrote.  “First, it provides evidence that boosting people’s trust in COVID-19 vaccines and reducing their fear of adverse effects from vaccination appears to be integral in increasing people’s willingness to be vaccinated.

“Second, the importance of social norms in shaping people’s willingness to be vaccinated was illustrated by the effects of the social norms treatment and reaffirmed by phone survey findings showing a clear relationship between vaccine intentions and people’s beliefs about whether their family and friends would be vaccinated.

“Third, health workers have a prominent role to play in increasing people’s willingness to receive a vaccine for COVID-19.

“In addition, the failure of the expert advice treatment to shift people’s views in the online experiment suggests that generic advice from experts will not serve as an adequate substitute for specific matter-of-fact advice received from trusted local health workers.

“One potential complicating factor, in PNG at least, is that vaccine hesitancy is comparatively high among health workers themselves. This suggests that high priority should be given to educating local health workers about COVID-19 vaccines so they can become advocates in their community for vaccination.

The rise of COVID-19 in Papua New Guinea

The report has an important list of limitations.

“There remains the possibility that people participating in the experiment differ from the population of PNG as a whole in a manner that was both not captured by the sociodemographic traits that we used to weight our data, and which had a direct impact on treatment efficacy.

“More importantly, both the survey and experiment asked people about their vaccination intentions: they did not measure whether people actually got vaccinated or not. For feasibility’s sake, we were limited to focusing on surveyed intentions. Yet, work in the United States has shown stated vaccine intentions and actual practice can differ. This is an acknowledged limitation.

“Another limitation with the experimental findings is that, although they changed participants’ views in the short-term, it is always possible that the effects of the information treatments waned over time.

“Finally, in a country like PNG, online messages have a potentially useful role in changing people’s views. Yet, the main task of increasing people’s willingness to be vaccinated will fall to community health workers. There is always a chance that the efficacy of information is different when delivered in person by health workers, rather than online.”