Impact of measles vaccination on clinical characteristics and outcomes in children in Ramadi, Iraq

Abstract

BACKGROUND

Measles is a highly contagious disease that caused by a measles virus. While measles vaccination is highly effective in preventing the disease, those who are unvaccinated or have not completed the vaccine series are at significant risk.

AIM

To assess the clinical characteristics and outcomes of measles in vaccinated vs unvaccinated children in Ramadi city.

METHODS

Clinically confirmed cases of measles at Al-Ramadi Teaching Hospital for Maternity and Children, identified between June and December 2023, were enrolled in this prospective cohort study. The cases were divided into two groups (vaccinated and unvaccinated). The clinical characteristics and outcomes were compared between unvaccinated and vaccinated children.

RESULTS

Of 289 kids, there were 222 (76.8%) children under 5 years old, and 161 (55.7%) boys. Around 2/3^rd children were unvaccinated. Besides, only 5 (4.9%) kids from the vaccinated group received three doses. Fever, maculopapular rashes, and cough were the most common manifestations. Unvaccinated children had higher rate of developing complications (pneumonia and diarrhea with P values 0.001 and 0.01 respectively), longer hospital admission period (P value = 0.008), and the need for respiratory care unit (RCU) admission comparing with the vaccinated children (4 cases for unvaccinated group vs 1 case for vaccinated group).

CONCLUSION

Unvaccinated kids were associated with more complications, longer admission hospital stays, and RCU admission. We recommend that public health directors utilize artificial intelligence tools to help control future measles epidemics.

Key Words: Measles; Measles vaccine; Young children; Vaccination coverage rate

Core Tip: Measles is a preventive disease by vaccine. Outbreak of measles can occur due to decrement in vaccination coverage rate. We aimed to compare vaccinated vs unvaccinated children with measles regarding disease severity and outcomes. The most affected children are in the age group < 5 years (222/289) and boys (161/289). The majority of affected children are either non-vaccinated or incomplete vaccination. Children with unvaccinated status are more prone to develop complications, respiratory care unit admission, and longer hospital stay.

INTRODUCTION

Measles is one of highly contagious diseases that caused by a measles virus. The virus is a spherical, single-stranded ribonucleic acid with a diameter of 100-250 nm, belongs to the family of Paramyxoviridae, and the genus is of Morbillvirus. Measles is characterized by high fever, cough, coryza, conjunctivitis, and a prominent exanthem. After an incubation period of 8-12 days, the prodromal phase begins with a mild fever followed by the onset of conjunctivitis with photophobia, coryza, a prominent cough, and increasing fever[1].

Before the introduction of the measles vaccine in 1963, major epidemics occurred every few years, causing millions of deaths annually. In the next years, the number of measles infections and deaths decreased with more spread of the vaccine globally[2]. Therefore, measles is considered as a vaccine-preventable disease, and vaccination programs had successfully caused marked decrease in the number of measles worldwide[2].

The eradication of measles has experienced a marked regression in recent years, with a significant increase in the number of measles cases and deaths in many countries. Countries with low vaccination coverage, especially those in sub-Saharan Africa and the Asia-Pacific region, experienced the highest burden of these cases[3].

Chains of transmission are common among household’s contacts, school-age children, and health care workers[4]. There are no latent or persistent measles virus infections that result in prolonged contagiousness, nor are there animal reservoirs for this virus. In temperate climate, annual measles outbreaks occur in the late winter and early spring[5].

The global epidemiology of measles shows a revival, with most cases occurring in unvaccinated or under vaccinated individuals, especially in lower-middle-income countries[6].

World Health Organization (WHO) recommended two-doses of measles vaccinations should be carried out. They are; monovalent measles vaccine and measles, mumps and rubella vaccine (MMR) which given at nine months and 15 months, respectively[7]. Between 2000 and 2022, measles vaccination is estimated to have prevented approximately 57 million deaths worldwide, despite fluctuations in certain years due to various factors[7].

During 2000–2019, the estimated coverage worldwide with the first dose of measles containing vaccine (MCV) increased from 72% to 86%, then declined to 84% in 2020, meaning that more than 22 million children did not receive their first dose in 2020. It further declined to 81% in 2021 during the coronavirus disease-2019 (COVID-19) pandemic, representing the lowest coverage since 2008. In 2022, first-dose MCV coverage increased to 83%[7]. The decline in measles vaccine coverage has not yet led to a noticeable increase in case numbers or deaths, possibly due to the impact of COVID-19 mitigation measures; such as mask-wearing, travel restrictions, and social distancing, which also helped reduce the transmission of other viruses, including the measles virus. Additionally, underreporting due to weak surveillance systems may have contributed to the apparent reduction[8].

From 2021 to 2022, reported measles cases increased to 67% globally, and the number of countries experiencing large or disruptive outbreaks increased by 68% as COVID-19 mitigation measures were lifted, surveillance improved, and declining MCV coverage left millions of children unprotected from measles[7]. Over 61 million doses of MCV were postponed or missed from 2020 to 2022 due to delays in supplementary immunization activities. Global coverage of the second dose also declined in 2020 to 70%, from 71% in 2019. By the end of 2022, 74% of children received 2 doses of measles vaccine[9].

Iraq has faced challenges with measles outbreaks, especially during periods of conflict and insecurity due to disruptions in healthcare services, population movements, and difficulties in implementing effective vaccination campaigns. The presence of internally displaced persons and refugee migrants further complicates disease control efforts. These outbreaks were exacerbated by decreasing population immunity due to conflict and insecurity across the country[10]. The reporting system in Iraq for infectious diseases including measles still facing challenges and the announced numbers may not reflect the real numbers on the grounds for the same aforementioned reasons above, and more than 1.3 million cases of measles have been reported from Iraq over the last 50 years, with an annual average of 25114 cases, 750-1250 deaths, and a case fatality rate of 3%-5%. However, adoption of the WHO Expanded Program on Immunization (EPI) in Iraq in the early 1980s reduced the average number of measles cases from 39000 to 9400 annually[11]. During COVID-19 pandemic, there was a marked reduction in measles vaccine coverage rate in Iraq. For example, a study compared the vaccination coverage rate in children under 5 years old in Nasiriyah, Iraq before and during the COVID-19 pandemic, and the result was a decrease in vaccination coverage rate from 83.7% in 2018 to 63.6% in 2020[12]. The last updated data that reported to WHO from August 2023-January 2024 ranked Iraq as number 3 (20469 cases) in top 10 countries with measles outbreaks and the last updated rank in November 2024 skipped to number 2[9]. Therefore, it is worthy to study the effect vaccination coverage rate on the measles outbreak and prognosis of the disease. Hence, this study aimed to assess the clinical characteristics and outcomes of measles infections in vaccinated vs unvaccinated children in Ramadi city, Anbar, Iraq.

MATERIALS AND METHODS

This prospected cohort study was conducted between June 2023 and December 2023, in Al-Ramadi Teaching Hospital for Maternity and Children. The study included children with measles of an age between 9 months and 14 years from both sexes. The current study was approved by the Ethical Approval Committee of the University of Anbar (Reference number 88, dated 2023-05-23). Informed consent was obtained from the parents of the children.

The diagnosis of measles was made clinically according to the following; generalized maculopapular rash lasting more than 3 days, Koplik’s spots, presence of fever and cough with coryza or conjunctivitis. Patients with an age below 9 months and above 14 years, received measles vaccine before 2 weeks from the onset of symptoms, unknown vaccine status, immune deficiency conditions, malnutrition, patients who had missing or incomplete data, atypical measles, and parents who decline to participate in the study were excluded.

The sample size was calculated based on the hospital-based design of the study using OpenEpi software. The calculation aimed to detect a relative risk of 2, assuming an incidence of 10% in the unexposed (vaccinated) group and 20% in the exposed (unvaccinated) group. Accordingly, the required sample size for each group was approximately 190. To account for a 10% dropout rate due to loss to follow-up or incomplete data, the total required sample size was adjusted to approximately 420 participants (210 per group). However, the total number of patients collected during the study period was limited to 289.

Data were registered for each participant regarding the following: Age, sex, residence, parents' education, vaccination status (complete, incomplete, or unvaccinated) was recorded based on the child's vaccination card or, when unavailable, according to parental recall, presence of malnutrition, history of immune deficiency, comorbid diseases, any index case of measles in the family, clinical features (fever, skin rash, cough, coryza, and conjunctivitis), complications (pneumonia, bronchiolitis, vomiting, diarrhea, otitis media, croup, tracheitis, keratitis, encephalitis, myocarditis, and others), laboratory results [white blood cells and differential, hemoglobin, platelets, erythrocyte sedimentation rate, and C-reactive protein], chest X-ray findings, hospital stay in days, admission to respiratory care unit (RCU), and outcome (deceased or full recovery).

Statistical analysis

SPSS version 26 was used for statistical analysis. Continuous variables were presented as means ± SD. While categorical variables were presented as frequencies and percentages. χ² test was used to compare categorical variables. Independent t-test or Mann-Whitney U test, as appropriate, was used to compare continuous variables. A P value of less than 0.05 was considered a statistically significant difference.

RESULTS

Of 289 of children with measles, there were 187 (64.7%) unvaccinated and 102 (35.3%) vaccinated. Out of 102 vaccinated children, there were 65 (63.7%) received single dose, 32 (31.4%) two doses, and only 5 (4.9%) three doses.

The mean age of the vaccinated (50.9 ± 39.9 month) was higher than unvaccinated children (39.9 ± 35.1 month). The majority of cases are in the age group under 5 years (n = 222, 76.7%), with a statistically significant difference observed between the two groups (P value = 0.021). The majority of non-vaccinated children are from rural areas (n = 132, 70.6%) with a significant difference between the two groups (vaccinated vs unvaccinated) regarding the residence of children (P value = 0.021). Other variables (sex and parents' education) show no significant (P value > 0.05) difference between the two groups (Table 1).

Table 1 Comparison of socio-demographics according to measles vaccination status of the study group, n (%).

Variables	Total (n = 289)	Not vaccinated (n = 187)	Vaccinated (n = 102)	P value
Age (months), mean ± SD
		39.9 ± 35.1	50.9 ± 39.9	0.0211
Age group
< 5 years	222 (76.8 )	171 (77.02)	51 (22.98)
≥ 5 years	67 (23.2)	16 (23.88)	51 (76.12)
Sex				0.589
Male	161(55.7)	107 (57.2)	54 (52.9)
Female	128 (44.3)	80 (42.8)	48 (47.1)
Residence
Rural	186 (64.4)	132 (70.6)	54 (52.9)	0.021
Urban	103 (35.6)	55 (29.4)	48 (47.1)
Father education				0.597
Illiterate	119 (41.17)	79 (42.2)	40 (39.2)
Primary	118 (40.83)	78 (41.7)	40 (39.2)
Secondary	25 (8.65)	16 (8.6)	9 (8.8)
College	19 (6.57)	9 (4.8)	10 (9.8)
Higher education	8 (2.78)	5 (2.7)	3 (2.9)
Mother education				0.809
Illiterate	142 (49.16)	89 (47.6)	53 (52)
Primary	101 (34.94)	69 (36.9)	32 (31.4)
Secondary	36 (12.45)	23 (12.3)	13 (12.7)
College	6 (2.07)	3 (1.6)	3 (2.9)
Higher education	4 (1.38)	3 (1.6)	1 (1)

¹Significant at 0.05 by independent t-test.

Fever is found in all patients (whether vaccinated or not). Following the fever, the commonest two symptoms are cough (n = 277) and typical skin rash (n = 277). While, the least manifestation is Koplik’s spots (n = 96, 33.2%). Skin rash, Koplik’s spots, and coryza are mostly affected the unvaccinated children with P values of 0.01, 0.001, and 0.002 respectively (Table 2).

Table 2 Comparison of signs and symptoms of measles among the study group, according to their vaccination status, n (%).

Signs and Symptoms	Total (n = 289)	Not vaccinated (n = 187)	Vaccinated (n = 102)	P value
Cough	277 (95.8)	182 (97.3)	95 (93.1)	0.088
Skin rash				0.011
Typical	277 (95.8)	182 (97.3)	95 (93)
Atypical	3 (1)	0 (0)	3 (3)
Koplik’s spots	96 (33.2)	82 (43.8)	14 (13.7)	0.0011
Conjunctivitis	268 (92.7)	170 (90.9)	98 (96.1)	0.106
Coryza	208(72)	146 (78.1)	62 (60.8)	0.0021

¹Significant at 0.05 by Pearson’s χ² test.

All laboratory tests are comparable between the vaccinated and unvaccinated children with measles apart from platelets counts (293.1 ± 89.4 in unvaccinated vs. 261.5 ± 84.5 in vaccinated children) with a statistically significant difference (P value = 0.003) between the two groups (Table 3).

Table 3 Comparisons of laboratory tests according to measles’ vaccination status of the study sample, n (%).

Laboratory tests	Not vaccinated, mean ± SD	Vaccinated, mean ± SD	P value
WBC count × 103	7.5 ± 3.2	7 ± 2.6	0.129
Neutropenia	11 (5.9)	3 (2.9)	0.266
Hemoglobin (mg/dL)	10.6 ± 1.4	10.7 ± 1.1	0.484
Platelets × 106	293.1 ± 89.4	261.5 ± 84.5	0.0031
ESR	10.7 ± 5.1	10.7 ± 4.8	0.988
Positive C-reactive protein	29 (15.5)	10 (9.8)	0.175

¹Significant at 0.05 by independent t-test. WBC: White blood cells; ESR: Erythrocyte sedimentation rate.

Only hospitalization stay period is a significant factor between the vaccinated (2.3 ± 1.6 days) and unvaccinated (3.1 ± 2.4 days) children with measles (P value = 0.008) as shown in Table 4.

Table 4 Comparison of index measles case, hospitalization stay, and admission to respiratory care unit according to measles’ vaccination status of the study sample, n (%).

Variables	Not vaccinated (n = 187)	Vaccinated (n = 102)	P value
Any index case of measles	107 (57.2)	54 (52.9)	0.484
Need hospitalization	125 (66.8)	61 (59.8)	0.232
Hospitalization (days), mean ± SD	3.1 ± 2.4	2.3 ± 1.6	0.0081
RCU admission	4 (2.1)	1 (1)	0.47

¹Significant at 0.05 by independent t-test. RCU: Respiratory care unit.

The highest complication is pneumonia (110 in unvaccinated vs 39 in vaccinated children), while the least complication croup (only 2 cases of unvaccinated children). Pneumonia and diarrhea are mostly affecting the unvaccinated children with P values of 0.001 and 0.01 respectively. However, otitis media is mostly affected the vaccinated children (P value = 0.005) as illustrated in Table 5.

Table 5 Comparison of complications with measles among the study group, according to their vaccination status, n (%).

Complications	Not vaccinated (n = 187)	Vaccinated (n = 102)	P value
Pneumonia	110 (58.8)	39 (38.2)	0.0011
Vomiting	84 (44.9)	46 (45.1)	0.977
Diarrhea	70 (37.4)	23 (22.5)	0.011
Otitis media	13 (7)	18 (17.6)	0.0051
Bronchiolitis	8 (4.3)	4 (3.9)	0.885
Febrile seizure	1 (0.5)	2 (2)	0.253
Encephalitis	3 (1.6)	0 (0)	0.198
Croup	2 (1.1)	0 (0)	0.295
Death2	3 (1.6)	0 (0)	0.198

¹Significant at 0.05 by Pearson’s χ² test.

²Death refers to measles-related mortality.

DISCUSSION

Measles vaccination plays a tremendous role in preventing lethal outcomes of the disease. Besides, the main reason for measles outbreak is the reduction in the vaccination coverage rate, which could be due to immigration, improper methods of importing vaccines, and genetic diversity of the measles virus[13]. The main outcome of the current study is the low number of participants (n = 102, 35.3%) taking measles vaccine and nearly 2/3^rd of them taking single dose.

It is well known that measles affects mainly younger children worldwide[14-16]. The present study aligns with this fact as it revealed that three-quarters of the participants below the age five years.

In a recent systematic review and meta-analysis reported that there is a high incidence of male sex in comparison with female in younger age group. This may be due to physiological and biological differences and not behavioral factors. However, at higher age groups, a male preponderance may be related to different exposure between the two sexes[16]. Our study also showed that the boys to girls’ ratio was 1.27: 1. This was close to a study from Iraq where the ratio was 1.3:1[17]. However, studies from the United States and Ukraine where the ratios were totally opposite for girls[18,19]. Most of children’s parents in this study were either illiterates or just finished primary school education, and this was in concordance with the characteristics of the sample studied by Zengin et al[20] from Turkey, which also pointed the role of the parents’ education on the vaccination status of their children and similar to our study about two thirds of the included children were unvaccinated, and only one third of the vaccinated children had completed their routine vaccine regimen. In Iraq, 2 studies had been done in both 2022, and 2024 with a relatively similar results in which 15.2% and one third of the included children have completed vaccination doses respectively[17,21]. Low coverage rate of measles vaccination was also reported in other studies[14,18]. The low vaccination rate in the above-mentioned investigations might due to the parents’ attitudes as well as cost of the vaccination. In comparison between measles cases in the current study, we can see that vaccinated group were significantly older as they might have the chance to take their complete vaccine routine or the requirement of kindergarten or school enrollment. This was also reported in the study from the United States[18], while the opposite was reported in the study from Turkey[20]. However, there was no significant differences in the age according to the vaccination status of the cases in a recent study from Somalia[22].

COVID-19 pandemic is one of the possible causes that led to decrease the number of vaccinated children due to more concentration on COVID-19 than other infectious diseases, people feared from reaching the health facilities during COVID-19 pandemic time and they still for months later on, and as many of the families had lack of trust in COVID-19 vaccine, they had the same idea regarding other vaccines at that time[13]. This highlights the need for increased public awareness campaigns by health institutions regarding the importance of vaccination in preventing the spread of communicable diseases, in accordance with the schedules set by the WHO, especially in developing countries. Moreover, more efforts are needed to vaccinate all the missed children in the past years by improving access to the health services, establishing unified databases for registering children and tracking vaccination status, and strengthening cooperation between the public and private sectors to finance and implement vaccination programs.

Fever and maculopapular skin rash are cardinal features of measles. The most prevalent symptom was fever followed by skin rash and cough. A relatively similar results found in other studies[19,22]. Likewise, typical rash was presented in the majority of patients whether they were vaccinated or unvaccinated in this study and other similar studies[19]. The skin rash in measles is presented after three to five days after symptoms’ onset, it is the sign of the measles virus-specific type 1CD4 and CD8T-cell adaptive immune response, as well as lymphocyte infiltration into the tissue sites of viral replication[23]. Moreover, atypical skin rash usually follows the vaccination as it only appeared in 3% of the vaccinated cases and most probably due to attenuated viral loads. The Koplik’s spots in our study were low in comparison with other studies[24]. This might due to the children in this investigation presented to the hospital after days of symptoms appearance and these spots might disappear within two to three days. Therefore, it is crucial for families to promptly visit nearby health centers, hospitals, or private clinics when their children develop a fever accompanied by a rash, in order to confirm or rule out measles and help prevent potential complications associated with the disease.

The present study found that complete blood count shows neutropenia in about 5% and one case had thrombocytopenia and the C-reactive protein was positive in 13.5%. Similarly, Ge et al[25] included 23 children with measles in Shanghai where 13% had neutropenia and 21% had high C-reactive protein. The presence of the rash in measles cases elevates C-reactive protein in the serum of the patients and that was clearly shown in the case-control study conducted by Güzelçiçek and Demir as they found significantly elevated C-reactive protein among the measles case group compared to controls[26]. Besides, our study reported that the hematological parameters were not different according to the vaccination status, but the platelet among the vaccinated children were significantly lower than unvaccinated. This finding is related to the adverse effect of the vaccine (especially the combined vaccine) as it was reported by Gan et al[27] who emphasize the role of the vaccine in secondary immune thrombocytopenia.

More than half of our patients had complications of measles like pneumonia, vomiting, and diarrhea. Besides, 1% of total cases who had serious complications like febrile seizures and encephalitis. These complications were expected because only deteriorated patients were presented for the emergency units, while the mild cases might need healthcare advice in primary healthcare centers or private clinics. Similar results found in another study in Iraq which reported that pneumonia in 28.5% of cases[17]. These serious complications did not appear in a retrospective surveillance concerned with measles outbreak in Babylon and Karbala governorates during the years 2020 to 2022[28], this was expected as they not developed serious complications and not needed to be admitted to the hospitals. On the other hand, Mina et al[29] had studied 77 unvaccinated children who developed measles and found that the virus affected their humoral immune memory and cause pneumonia in 54% from the same postal code area, all of them had sever measles. Another study in Pakistan showed that pneumonia was found among 95 (63.3%) cases[30]. Furthermore, in our investigation, pneumonia among unvaccinated children was significantly higher than vaccinated children, this is thought to be caused by low immunity among unvaccinated cases of measles or incomplete vaccination in addition to the possibility of nosocomial infection in the admitted cases as it was described by Khan et al[30]. Similar results were found in a study by Nezgoda et al[31].

Additionally, the present study revealed that diarrhea was more prevalent in unvaccinated children. This aligns with the results from other studies[18,32]. Otitis media as a complication of measles in our study was significantly higher in vaccinated children. Among all complications of 2676 notified measles cases in an outbreak in Netherlands, otitis media was significantly higher among vaccinated and specifically those with one dose of vaccination[33]. On the other hand, no significant differences were registered in the Turkish study regarding otitis media despite it was the most prevalent complication among the measles patients[34]. Therefore, otitis media may occur in any child with measles, regardless of vaccination status, as measles, like other upper respiratory infections, can affect the middle ear through the Eustachian tube. Other studies also show some serious complications in severely infected patients ranged from 37%[18], 41.1%[35] to 100%[34] especially among unvaccinated children. Febrile seizure also recorded in one measles case in the study from Turkey[34]. This underscores the importance of providing extra care to measles patients, particularly those who have not received or completed their vaccination schedule, in order to prevent disease-related complications.

The current study also revealed that 55.7% of the cases were with index family cases and 64.4% needed admission for about three days. Similar days of admission had been found in a study in Saudi Arabia in 2023 with a high percentage of hospital admission (88.9% of total cases) and 85% of them were unvaccinated[14]. Besides, the current study reported that five cases were seriously ill and needed admission to the RCU and three of them unfortunately died (1% fatality rate). This aligns with other studies[14,19]. It is understandable that measles generally more severe in unvaccinated children, and the more the severe the disease the more time needed to be treated and thus more hospitalization time needed for unvaccinated kids. This was in consistent with other similar studies[18,34]. However, the studies didn’t find any significant differences in hospitalization stay time according to vaccination status against measles. In a surveillance review of 864 suspected cases of measles between 2017 to 2021 in Milan, Italy reported that 40% of the cases were index cases[36]. The fatality rate of measles in a study from Somalia was 1.8%[22]. In a recent systematic review reported that measles fatality rate ranged from 0% to 13.4% in studies from different districts of Ethiopia and 1.2% in one study from Somalia[37]. The difference among the various studies is thought to be due to variance in cases severity, management, vaccination status, and/or the immunity in these areas.

Although rare, vaccine failure should be discussed with key stakeholders in the governmental health sector. A rapid response to such crises requires the development of emergency plans to address disruptions to vaccination programs, such as those caused by conflicts or natural disasters. In addition, coordination with local health authorities is essential to ensure the availability of IgM testing to confirm the diagnosis of suspected cases.

It is worthy to note that artificial intelligence (AI) tools can play a significant role in controlling future measles epidemics through the following approaches[38]: (1) Early detection of outbreaks: AI systems can analyze data from institutional health records, social media platforms, and newly published scientific studies in real time to identify early signs of a measles outbreak before it escalates into an epidemic; (2) Predictive modeling: Machine learning algorithms can predict when and where outbreaks are likely to occur based on factors such as vaccination coverage, migration patterns, history of previous epidemics, and environmental changes, including weather patterns; (3) Targeted vaccination campaigns: AI can assist health officials in identifying regions with low vaccination coverage and provide evidence-based recommendations for effective immunization strategies to enhance vaccine uptake and improve campaign efficiency; (4) Transmission tracking and visualization: AI tools can help public health authorities monitor and visualize the spread of infection, enabling timely interventions to prevent further transmission of the virus; (5) Resource allocation: AI can support optimal distribution of healthcare resources, including medical personnel, vaccines, and public health campaigns, based on real-time outbreak data and geographic disease distribution; and (6) Combating misinformation: AI-powered monitoring systems can detect vaccine-related misinformation on digital platforms, allowing health authorities to proactively launch awareness campaigns to promote accurate information and increase public confidence in vaccination programs.

The current study has four limitations. First, the sample size was small. During a measles outbreak, a considerable number of patients with suspected or confirmed measles are hospitalized. However, strict inclusion criteria and specific exclusion factors limit the number of eligible participants. Additionally, the relatively short duration of the study further constrained the sample size. It is also important to note that most measles cases resolve spontaneously without the need for hospitalization, which may have further reduced the number of cases available for enrollment. Second, during the study period, there was an imbalance in the number of patients between the two groups, which may have influenced the statistical analysis. Third, the study was conducted at a single center in one region of Iraq, limiting the generalizability of the findings. Fourth, recall bias in reporting vaccination history may have negatively impacted the accuracy of the results. Nonetheless, the results offer an objective assessment of measles manifestations and outcomes within the context of our hospital. The data collected during the study period, along with their statistical analysis, could play a significant role in preparing for future measles outbreaks, even in settings where public health response capabilities are limited.

CONCLUSION

There is a high prevalence of unvaccinated children, who are at increased risk of serious measles-related complications, including pneumonia, hospital admission, RCU admission, and even death. While measles cases have also been reported among fully or partially vaccinated children, these cases tend to be fewer in number and milder in severity compared to those in unvaccinated children. The Iraqi government should enhance vaccination promotion efforts and expand access to vaccination services, particularly in rural and underserved areas. It is recommended that public health directors adopt AI tools as part of their strategy to control future measles epidemics.