The global community is currently facing a pandemic, the coronavirus disease, better known as COVID-19. ^{Reference Płusa1–Reference Faber3} The first case of the COVID-19 virus was discovered in Wuhan City, Hubei, China, in mid-December 2019. ^{Reference She, Jiang and Ye4,Reference Wu, Chen and Chan5} Since then, the global transmission of COVID-19 has splurged around the world. By June 1, 2021, the virus had infected over 171 468 758 people worldwide, with 3 565 021 deaths confirmed. ⁶ The first case of the COVID-19 infection in Malaysia was detected on January 25, 2020, which originally came from China. Although the majority of COVID-19 cases can be traced back from foreign countries, the rise of local clusters in Malaysia began to escalate in early 2020. Several local clusters such as the cluster of religious gathering of Tablighi Jamaat in Kuala Lumpur in February 2020, the cluster of Sabah state election in September 2020, the cluster of Top Glove factory employees in late 2020, followed by the festive season in early 2021 have further worsened the transmission of COVID-19 in Malaysia. ^{Reference Dollah, Jafar and Joko7} From February 2020 to August 2021, the total number of cases reached over 20 000 per day, leading to the downfall of the premiership of Muhyiddin’s cabinet which lasted only 17 months. ⁸ The cases of infection fell to roughly 2000–3000 cases in early January 2022. However, the arrival of the Omicron variant had further again sparked a surge during February 2022. As of March 8 2022, the number of COVID-19 infections in Malaysia has reached 30 000 daily cases. ⁹ COVID-19 contributes to a significant global fatality ^{Reference Nuryana and Fauzi10} and other global concerns such as the global economic crisis, ^11,12 issues of mental health, ^{Reference Sheek-Hussein, Abu-Zidan and Stip13–Reference Miki, Yamamoto and Inoue15} and other public health problems. ^{Reference Sharma and Bhatta16,Reference Pausé, Parker and Gray17}

The COVID-19 pandemic has indeed sparked a global calamity, alarmed state governments around the world to increase preparedness and response to halt the transmission of the virus. As a result, state governments around the world had initiated security and public health measures to deal with the COVID-19 pandemic, including the long-term vaccination program. Existing studies have also demonstrated that the vaccine formulated against COVID-19 increases immunity in human bodies and halts the transmission of the virus. Herd immunity can be achieved if 80 to 90% of the total population in a country receives inoculation against COVID-19. ^{Reference Fine, Eames and Heymann18} However, the growing resentment among the public against the vaccination program may have decreased global efforts to contain the virus. The rejection of the vaccine program has been recently coined as “vaccine hesitancy.” ^{Reference Sonawane, Troisi and Deshmukh19} Therefore, understanding the growing reluctance of participating in the immunization program is crucial to ensure the continuity of global preparedness in curbing the spread of the virus.

The Malaysian Government, for instance, has imposed medical and non-medical measures to manage the pandemic. These include border restriction with the implementation of the Movement Control Order (MCO), the declaration of national emergency and the introduction of public health measures such as the banning of mass gathering, social distancing, and the use of face masks, among others. ^{Reference Aziz, Othman, Lugova and Suleiman20,Reference Kuok Ho21} In line with the advisory of the World Health Organization (WHO), the Malaysian Government states that the only way to contain the threat of the COVID-19 pandemic is through the implementation of the vaccination program. ^{Reference Jafar, Dambul and Dollah22} As a result, the Malaysian Government introduced the National COVID-19 Immunisation Programme (PICK) on February 24, 2021. ²³ The vaccine brands provided by the Malaysian Government for the Malaysian populations are Pfizer BioNTech, ^{Reference Tee24} Sinovac (CoronaVac), ^{Reference Chung25} and Oxford-AstraZeneca. ²⁶ The aim of the PICK program is to contain the transmission of the COVID-19 virus. Controlling transmission is crucial for restoring a safe environment. This would enable the public to resume normal life activities that would certainly help the government in stimulating the national economy. ^{Reference Schuchat27}

However, the success of the vaccination program is highly dependent on the attitude and perception of the public: the recipients of the vaccine. Unfortunately, in Malaysia, the response to PICK has been disappointing since most Malaysians are not interested in inoculation, ^{Reference Rumetta, Abdul-Hadi and Lee28} especially the COVID-19 vaccine. ^{Reference Rodzi29} The nationwide readiness to participate in the program has largely contributed to the low turnover of the vaccination program. According to Khairy Jamaluddin, the Minister in charge of PICK, only 6.1% of Malaysians have registered for the vaccination program in March 2021. Although the government has pledged to provide free vaccinations to all Malaysians, the low registration indicates that the government has fallen short in achieving herd immunity. The Malaysian Government also introduced consolation (rewards) and other incentives to vaccine recipients in several states throughout Malaysia, signaling its commitment to increase immunization rates among its population. ^{Reference Abdullah30} Unfortunately, the issue of vaccine hesitancy still persists today. ^{Reference Pauzi31} In fact, as of March 24, 2022, almost 1 year after the government had initiated PICK, only 79% of the total Malaysian population has received 2 doses of the vaccine.

Communication deficiencies are one of the causes of vaccine skepticism and can hamper vaccination acceptance in any circumstances. At the same time, communication may be an effective tool, if well planned and integrated, for influencing the behaviors of populations on a variety of health concerns, such as vaccine hesitancy. ^{Reference Goldstein, MacDonald and Guirguis32} In middle-income and low-income nations, the lack of communication tools impedes the governments’ attempts to prevent the dissemination of misleading information concerning immunization programs. This is one of the greatest challenges to the effectiveness of the population vaccination campaign. Therefore, according to the World Health Organization, ³³ communication skills are lacking across the globe and must be strengthened. In addition to providing excellent targeted communication to explicitly address hesitation and boost vaccine uptake, it is necessary to address inadequate communication to encourage immunization regardless of the circumstances. Moreover, vaccine hesitancy has also been associated with psychological factors such as the presence of paranoid sentiments, ^{Reference Murphy, Vallières and Bentall34} disgust sensitivity toward blood and needles, ^{Reference Hornsey, Harris and Fielding35} and overly selfish attitudes. ^{Reference Rieger36} Concerns about safety (eg, feeling unsafe by taking vaccines, being concerned about vaccine side effects, and conflicting with religious beliefs) also contribute significantly to the phenomenon of vaccine hesitancy, ^{Reference Kanyanda, Markhof, Wollburg and Zezza37–Reference Ackah, Woo and Stallwood40} in addition to being triggered by milieu issues such as perceived social norms and perceived susceptibility to COVID-19. ^{Reference Davis, Yimam and Kalam41}

The situation is worrying, particularly in Sabah where the state recorded the lowest registration for PICK. ^{Reference Jafar, Mapa and Sakke42} On July 16, 2021, a minuscule rate of 13% from the total state population were vaccinated. The state scored the lowest rate, which is far behind the government’s target to achieve herd immunity. On March 24, 2022, only 62% of the total population in Sabah have received 2 vaccination doses. ⁴³ Apparently, rejecting vaccination will reduce the achievement of herd immunity as well as hamper the government’s efforts to contain the virus. ^{Reference Salathé and Bonhoeffer44} Therefore, the aim of this study is to understand what fuels the negative perception of the vaccination program among the population of Sabah based on 4 main components: safety, communication, psychology, and milieu. The results of this study are extremely important as supplementary data for assisting the government in increasing public participation in the vaccination program. Once the source of vaccine hesitancy is identified, it will be simple to implement measures to strengthen the vaccination program.

Methods

Data Collection

Due to the constraints of the COVID-19 pandemic, this study employs online questionnaire instruments using Google Form. Google Form, as a medium for data collection, aids in maintaining public health safety and other related security concerns in conducting research during the pandemic. Online instruments are also beneficial in widening the response rate among participants. This study is based on a simple random sampling of 1024 Sabahans who participated in the survey. The sample of this study consisted of Sabah citizens (inclusion criteria), except those 18 years of age and under (exclusion criteria). This is because, when this study was conducted, only individuals ages 18 years and above were eligible to be given the vaccine. On the other hand, children ages 12 to 17 can take the vaccine with their parents’ consent. ^{Reference Adnan and Remaja45} More than half of the respondents were female (n = 551, 53.8%) ages 41 years and under (n = 814, 79.5%).

The total population of Sabah is approximately 3 904 500. ⁴⁶ Therefore, a minimum of 400 samples is required to be considered as broadly sufficient in representing the entire population of Sabah. ^{Reference Yamane47} In terms of district representation, respondents have been drawn from all zones throughout Sabah, as follows: 9.2% from the Northeast Zone, 9.6% from the Southeast Zone, 13.7% from the Southwest Zone, 17.6% from the Interior Zone, 21.9% from the Northwest Zone, and 28.1% from the Midwest Zone. The purpose of selecting representative responders from each zone is to acquire more comprehensive data. The data collection process was conducted for 2 weeks, starting from March 30, 2021, to April 15, 2021.

Questionnaire (Google Form)

The questionnaire instrument is divided into 2 sections: A and B. Part A focuses on demographics, whereas Part B focuses on respondent perceptions toward the PICK program. In Part B, the questions were created in the form of a Likert scale with 5 possible responses: “1 (Strongly disagree),” “2 (Disagree),” “3 (Neutral),” “4 (Agree),” and “5 (Strongly agree).” The purpose of the Likert scale is to assess the degree of agreeableness for each question. All questions in Section B have been formatted in the opposite form (Table 1). For instance, respondents who answered “1 (Strongly disagree)” have a high, positive perception toward the PICK program. On the contrary, the score “5 (Strongly agree)” represents a negative perception of the PICK program. The questions have been derived from the previous works of Fauzi et al., ^{Reference Fauzi, Razif and Ramli48} Rumetta et al., ^{Reference Jafar, Dambul and Dollah22} and Sallam. ^{Reference Sallam49}

Table 1.

Variables used to determine the reaction of the Sabah community toward the vaccination program

Statistical Analysis

This study used the statistical analysis consisting of the K-means clustering, the Mann–Whitney U test, the mean score, the spatial analysis, and frequency in extracting the outcomes from the raw data. The K-means algorithm analysis is tailored for group respondents, which can be divided into 2 clusters based on their responses to the PICK program. The function of the K-means algorithm analysis is to produce group variables with a high degree of similarities within each group and a low degree of similarities between groups. ^{Reference Hastie, Tibshirani and Friedman50,Reference Morissette and Chartier51} The Elbow and Silhouette method determines the optimum number of clusters. ^{Reference Rousseeuw52,Reference Damayanti and Wijayanto53} The Elbow and Silhouette graphs are generated through machine learning analysis known as Python to determine the optimum number of clusters, which turned out to be 2, as indicated in Figure 1.

Figure 1.

Determination of the optimum number of clusters.

The K-means clustering analysis in this study uses the spatial mapping of the Geography Information System (GIS) to identify the distribution of each cluster based on the localities in Sabah. The mean score for this study is intended to compare the population’s response to the COVID-19 vaccination program for each cluster group. This is to determine whether the responses are more likely to be positive or negative. The mean scores are divided into 5 groups to interpret the data: very low (1.00–1.80), low (1.81–2.60), moderate (2.61–3.40), high (3.41–4.20), and very high (4.21–5.00). ^{Reference Baba54} The greater the mean score value, the more it reflects on higher negative perceptions of respondents toward the PICK program. Public perception is analyzed using 4 components: communication, safety, psychology, and milieu.

The mean value of Cluster 1 is more than that of Cluster 2 for all 4 attributes, indicating that Cluster 1 can be identified as the “vaccine hesitancy” category. A Mann–Whitney U test with a confidence level of 95% (P = 0.05) was used to measure whether any significant link is present between these 4 components and the demographic variables of respondents. However, the normality test using the Kolmogorov–Smirnov test revealed that the data from Cluster 1 are not normally distributed. Therefore, this study suggests that the non-parametric analysis, such as the Mann–Whitney U test, is the most suitable instrument to compare and determine the factors (or components) related to the vaccination program within the clusters identified in this study.

Results

Sociodemographics of Respondents

The K-means analysis indicates that the number of respondents in Cluster 1 consists of 55.9%, whereas Cluster 2 recorded 44.1%. Cluster 1 also has more respondents (a total of 60%) who had not registered for the vaccination program as opposed to the 19% in Cluster 2. In terms of employment, the average respondents within Cluster 1 consist of 24.1% of private employees and 24.1% of unemployed. On the other hand, Cluster 2 is predominantly drawn from government civil servants. Cluster 1 is more affluent in educational background with 41.4% as compared to 31.2% in Cluster 2. Cluster 1 has a higher rate of adults between 18 and 40 years old (82.3%). Cluster 2 also has adults between 18 and 40 years old (75.9%). Gender representation in both clusters has shown a similar trend, with females outnumbering males (Table 2).

Table 2.

Sociodemographics of respondents

Public Response Toward the PICK Program in Sabah

Based on the data, it was found that respondents in the Cluster 1 category displayed a high negative response (M = 3.25, SD = 0.288) toward the vaccination program as compared to Cluster 2 (M = 2.44, SD = 0.375) due to communication problems (M = 3.37, SD = 0.439). In this regard, the Cluster 1 group views that the information related to vaccines (M = 3.88, SD = 0.799) and the immunization program (M = 3.78, SD = 0.787) was difficult to obtain. They also found it difficult to trust the information from the mainstream media (M = 3.86, SD = 0.785). Psychological factors have also influenced this group in becoming more pessimistic toward vaccines (M = 3.33, SD = 0.588). In their opinion, it is sufficient to adhere to the standard operating procedures (SOPs) to prevent COVID-19 transmission (M = 3.69, SD = 0.949). This group also has a negative view of vaccines in relation to their milieu component (M = 3.30, SD = 0.536) and safety (M = 2.99, SD = 0.623).

Cluster 2, on the other hand, warmly welcomes the COVID-19 vaccination program, which can be identified through the psychology components (M = 2.01, SD = 0.562) and safety (M = 2.37, SD = 0.406). They do not consider vaccines as a conspiracy (M = 1.81, SD = 0.844) and are safe to use (M = 1.71, SD = 0.658). In addition, this group was not affected by the viral trends of social media in illustrating the negative aspects of the vaccine campaign (M = 2.19, SD = 1.01) (Table 3).

Table 3.

Perceptions of the COVID-19 vaccination program in Sabah

The geographical space domain reveals that the Cluster 1 population dominated 17 out of 26 total districts in this study. The average population identified in Cluster 2 covers 7 districts: Kuala Penyu, Beaufort, Papar, Keningau, Tambunan, Ranau, and Lahad Datu. Most of these districts in Cluster 2 are situated within the Southwest and Interior Zones (Figure 2).

Figure 2.

The distribution of Cluster 1 and Cluster 2 based on the districts of Sabah.

Source: modified from the Department of Sabah Town and Regional Planning, 2021.⁵⁵

Table 4 presents a comparison of the community’s reaction to the COVID-19 immunization program based on the characteristics of sociodemographic information in Cluster 1. According to Table 4, there is a substantial difference between respondents who have not registered for the vaccination program compared to those who have registered, and this can be measured from the component of safety (0.001, P < 0.05) and psychological components (0.001, P < 0.05). In this case, the mean value of respondents who have not registered for the vaccine is higher (MR = 325.9) than those who have registered for the vaccine (MR = 227.4) based on their perception of the safety component. Similarly, the mean value for the psychological component among respondents who have not registered for the vaccine is higher (MR = 319.1) than those who have registered for the vaccine (MR = 237.7).

Table 4.

Comparison of public reactions toward the COVID-19 immunization program with sociodemographic factors in Cluster 1

These findings indicate that individuals who have not registered for the vaccines are more skeptical toward the safety of the vaccine as they have been influenced by psychological elements compared to those who have registered for the vaccine. This study also found that there is a substantial difference in the educational background (P < 0.05) between respondents with low education and highly educated respondents, which can be measured through the safety component. This reflects on their negative perceptions regarding the vaccination program. The group with a low education background also has a higher mean value in the safety component (MR = 310.6) than the highly educated group (MR = 269.4). The analysis from this result indicates that those with low education have high negative perceptions in relation to the safety component of the vaccine as compared to the highly educated group.