As a worldwide pandemic, coronavirus disease 2019 (COVID-19) is referred to as a public health emergency of international concern [1]. Iraq’s first confirmed cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections were reported in Najaf governorate in February 2020. By April, there was a sharp rise in the number of confirmed cases in Baghdad, Basra, Erbil, Sulaymaniyah, and Karbala, resulting in a great burden on the social and mental health all over Iraq [2, 3].

So far, over 2,460,844 cases and 25,356 deaths due to COVID-19 have been reported in Iraq till 20 October 2022 [4]. Control measures such as containment measures, mask mandate and social distancing, case detection, and tracing were taken to reduce the spread of the infection [5]. Despite the potential effectiveness of such strategies, successful control of severe COVID-19 only became possible with the development of safe and effective vaccines. Zhen et al., in a meta-analysis of 51 studies, indicated that Pfizer-BioNTech and Moderna vaccines had observed effectiveness of 91.2% and 98.1% against infection [6].

As of 11 October 2022, Iraqis have received 19.3 million doses of COVID-19 vaccine, and 18.8% of the population (7.57 million people) are fully vaccinated [4], while some neighboring countries such as Iran and Egypt have fully vaccinated almost 70% of their population [7]. Studies have shown that vaccine rollouts have been only partially successful. In a review, Troiano and Nardi have demonstrated that a maximum of 77.6% of the general population have declared they will accept the COVID-19 vaccine; with the number decreasing according to the socioeconomic status of the population. Factors such as working status, religiosity, political views, and even gender have been proposed to influence vaccine acceptance [8]. Sherman et al. have indicated that over 75% of participants in an online survey completed in the United Kingdom were willing to receive COVID-19 vaccine, with others believing that vaccination was only needed by those at serious risk of illness, or is just a means for manufacturers to make money [9]. Another study conducted in Italy revealed that over 90% of participants desired to be vaccinated [10]. Studies in low/middle-income countries demonstrated widespread conspiracy theories and reluctance to receive COVID-19 vaccines [11, 12].

It is important to understand socio-demographic factors that affect vaccine decision-making [11]. Moreover, successful vaccine rollout depends on identifying and mitigating factors associated with vaccine hesitancy and knowing the sociodemographic factors associated with vaccine hesitancy would aid health decision-makers in adopting specific measures to prompt vaccination among targeted groups [12]. While COVID-19 vaccine acceptance has been documented as low among Kurdish people (13%) [13], so far, no studies have focused on the factors associated with vaccination coverage among Iraqis. This study reports COVID-19 vaccination coverage amongst populations of host communities, internally displaced persons (IDPs) and refugees in five governorates of northern Iraq. In addition, it reports factors associated with vaccination acceptance in the areas surveyed.

Infectious diseases can be successfully controlled through vaccination; therefore, vaccination can be labeled as one of the most remarkable achievements of science. However, vaccination success can be negatively affected by people’s hesitation to get vaccinated. Therefore, there has always been the challenge of encouraging people’s desire to be vaccinated [16]. Iraq has experienced an alarming prevalence rate of COVID-19, with high daily reported new cases and hundreds of deaths reported monthly from June 2020. Therefore, combating COVID-19 in Iraq is only possible through vaccination [17]. However, vaccination hesitancy is still a big barrier to reaching high rates of vaccination in Iraq.

The results of the current study revealed that nearly half of the participants had not been vaccinated at all. In a study conducted on Iraqi population, Alatrany et al. reported that 68% of the study population had received atleast one vaccine dose; which is close to the results of our study [18], while in a report of vaccination rates in Duhok governorate of Iraq Kurdistan region, Abdulah revealed that 83.5% of the participants had not received a vaccine with 51.4% of them not intending to receive one [19]. This number falls short in comparison to neighboring countries such as Iran and Egypt in which almost 70 percent of the population have been reported to be fully vaccinated [7].

In their review Troiano and Nardi report that vaccination rate varies between the studies with a maximum of 77.6% of general population declaring that they will accept the COVID-19 vaccine [7] pointed out that vaccine acceptance can vary from community to community and from country to country, and this variation can be justified through various factors like the people’s trust in their government and national health organizations, education and public awareness, the economies of the countries, social and political conditions, and COVID-19 prevalence and mortality rates in the local community [20]. Over 40% of participants had been vaccinated by two doses and 1.56% received their third dose. In a similar study by Qin et al. (2022), it was reported that the rate of vaccine acceptance is higher among those who are willing to receive the third dose of vaccine. They also remarked that people in least developed countries are less likely to receive the third dose, which can be attributed to vaccination hesitancy [21].

The results of the current study showed that the participants’ place of residence, age group, gender, nationality, level of education, and occupation had a significant effect on COVID-19 vaccination coverage. Similarly, other studies indicated that willingness to receive COVID-19 vaccine varies in different communities and countries and is significantly influenced by factors like urban residence, being a physician or health professional, having children, previous interaction with someone infected by COVID-19, access to the media, and good practice of COVID-19 preventive measures [22, 23]. As suggested by the Health Cluster bulletin (2022), to achieve a broader coverage rate for COVID-19 vaccination, the epidemic indicators require continued emphasis by health partners on the importance of prevention, physical distancing, masking, and vaccination countrywide [13].

Regarding the reasons for avoiding vaccination in the present study, nearly 17% of the participants believed that the COVID-19 vaccine was not safe, 11.94% feared infection, and 10.79% feared its possible side effects. About 9.77% of them were generally against the principle of vaccination, and 6.46% said that vaccination could not be an effective option against COVID-19. In a study on the Iraqi population, Alatrany et al. [18] reported that distrust in government, social norms, perceived benefit of vaccination and severity of COVID-19 were significant predictors of vaccine hesitancy, while in contrast to our study, factors such as perceived infection likelihood and gender were not significant predictors of vaccine hesitancy. Abdulah has also investigated the vaccine hesitancy in Duhok governorate of Iraq Kurdistan region and reported that more than half the population are concerned about benefit of vaccines, their side-effects and new vaccine technologies. In his study it was demonstrated that education levels, occupation and concerns of adverse side-effects are significantly associated with the intention to vaccination while gender was not shown to have such association [19]. Tahir et al. have also investigated vaccine hesitancy in four governorates of Duhok, Erbil, Sulaiymaniy and Halabja of Iraq Kurdistan region and have reported that as much as 35% of the participants rejected to be vaccinated. Tahir et al demonstrated that age, occupation, higher level education and loosing a family member due to COVID-19 were significantly associated with vaccination intention [15]. In line with these findings, Mubarak et al (2022) reported that high acceptance of COVID-19 vaccine in university students in Saudi Arabia is determined by belief in the effectiveness and safety of the vaccine and trust in its capability to prevent the consequent complications, while fear of side effects is regarded a major factor for refusing vaccination [24].

Studies have reported varying degrees of COVID-19 vaccine hesitancy among refugees/migrants and asylum seekers, ranging between 10 and 40 percent [25]. Our results indicate that the reasons for avoiding vaccination was mostly similar between the host communities, IDPs and refugees which consisted of belief of vaccination being unsafe and not effective, fear of infection and being against the principle of vaccination in general. In a systematic review of vaccine acceptance and hesitancy among migrants and foreign workers, the potential barriers against vaccination were vaccine safety, mistrust of vaccines and healthcare system in general, newness of vaccines and low confidence in COVID-19 vaccines, assuming the disease is not dangerous, inadequate information, logistical barriers and religious prohibition [26].

Several interventions have been conducted in studies to increase the public’s willingness to receive the vaccine. A systematic review of 39 studies shows that communicating about vaccine concerns on social media does not reduce willingness to get vaccinated, but making vaccination mandatory has negative impact on vaccine uptake [27]. Governmental incentivization and persuasion are important factors to achieve higher vaccination coverage. Although, monetary incentives can increase the vaccination coverage [28], some believes incentives alone does not effective measures to encouraging vaccination [29]. It seems that financial incentivization do not enhanced COVID-19 vaccination in the vaccine hesitant [30]. Persuasion, prestige-based incentives, and adopting behaviorally informed policies are possible alternative means [29, 31, 32]. As a general recommendation, association of vaccine coverage with demographic, personal and geographical factors emphasize that a combination of social, cultural and even religious parameters should be considered to adopt effective measures to achieve proper vaccination coverage rate.

Our study is limited by no reports on the rate of refusal to participate in the study, which might lead to selection bias, not assessing the effect of the available vaccine type on participants vaccine hesitancy, and not investigating the accessibility of vaccination facilities, which might hinder vaccination in rural, deprived, or underprivileged districts. Future studies could address these issues in order to better investigate the contributing factors to vaccine hesitancy.