Prevalence of sexually transmitted infections, and its associated factors among students in Ethiopia: a systematic review and meta-analysis study

Background Sexually transmitted infections (STIs) are illnesses mainly spread through unprotected sexual activity. There is a scarcity of aggregate evidence in Ethiopia. The aim of this review was to assess the pooled prevalence of STI, and its associated factors among students in Ethiopia to fill the aforementioned gap. Methods We extensively searched the bibliographic databases of PubMed, Scopus, and Google Scholar to obtain eligible studies. Further screening for a reference list of articles was also done. The Microsoft Excel Spreadsheet was used to extract data, and Stata 17 was used for analysis. The PRISMA-guidline and Newcastle-Ottawa quality assessment scale were used for quality appraisal. To check heterogeneity, the Higgs I2 and Cochran’s Q tests were employed. Sensitivity and subgroup analysis were implemented. To detect publication bias, Egger’s test and funnel plots were used. Results The pooled prevalence of STI among students in Ethiopia was 13.6% with a 95% CI (10.2, 17). Findings from sub group analysis based on student category shows that the pooled prevalence of STI were 14.5% among University students, 14.2% among college students and 10.6% among high school students. Having multiple sexual partners (AOR 3.31; 95% CI: 2.40–4.57), not using condoms during sexual intercourse (AOR 2.56; 95% CI: 1.72–3.81), and having poor knowledge about sexually transmitted infections were 3.08 times (AOR 3.08; 95% CI: 1.84–5.15) significantly associated with STI. Conclusion The pooled prevalence of STIs among students in Ethiopia was high, and factors like having multiple sexual partners, not using condoms during sexual intercourse, and having poor knowledge about sexually transmitted infections were significantly associated with STIs. Hence, reduce STIs among students, strengthening sexual and reproductive health services, raising awareness about transmission and prevention, and promoting consistent condom use through health information dissemination is crucial. Further qualitative studies are suggested to explore the barriers and facilitators of STI prevention.


Introduction
Sexually transmitted infections (STIs) are illnesses mainly spread through unprotected sexual activity [1].More than 30 different bacteria, viruses, and parasites cause STIs.From these microorganisms, four of them namely, syphilis, gonorrhea, chlamydia, and trichomoniasis can be cured [2].
STIs are diagnosed by laboratory testing and clinical presentation.Laboratory diagnosis is the most accurate technique of diagnosis, but because it requires advanced laboratory facilities and skilled workers who can execute technically difficult operations, it is expensive and impracticable in many contexts [3].In resource-limited countries including Ethiopia, most laboratory investigations to detect STIs are not feasible, thus the diagnosis is based on a syndromic approach which was recommended by WHO [3,4].
STIs are a major public health concern globally and especially among women in resource-limited countries [5].Even though strategies were applied for decades, the magnitude of STIs is still high [6].STIs are among the most common communicable diseases worldwide, and their global burden remains high.According to a World Health Organization (WHO) report, an estimated 374 million new infections with one of four curable STIs occur each year [2].Globally, the magnitude of these infections varies by region and it is relatively high in the African region [7] with a higher proportion in Sub-Saharan Africa [8].
Different factors, including age, marital status, occupation, level of family income, residence, level of education, length of partnership with current partner, the age difference between the woman and her partner, parity, history of abortion, history of stillbirth, history of STI, gestational age, sexual history with a new partner, number of sexual partners, age at first sexual intercourse, perineal hygiene cleaning practice, and condom use affect STI prevalence [9][10][11].Because these factors influence social and sexual networks, access to and provision of care, willingness to seek care, and social norms regarding sex and sexuality, they may pose serious barriers to STI prevention [12].
In addition to the physical health problems including pelvic inflammatory disease (PID), infertility, ectopic pregnancy, chronic pelvic pain, cervical cancer, and urethral stricture [13,14], diagnosis with STI will have a negative psychosocial and economic impact on the patient and their family [7,15].
Investigating STI among students are crucial because adolescents and young adults are at a higher risk of contracting STIs due to factors such as risky sexual behavior, lack of information, and vulnerability to peer pressure [16].Educating students about VCT and HIV prevention can lead to early adoption of healthy behaviors, reducing the long-term risk of HIV transmission and other STIs [17].Students represent the future generation, and instilling knowledge and positive attitudes towards STIs can have a ripple effect on the broader community [16].
In Ethiopia, though evidence regarding the magnitude is limited, available literature indicated a higher prevalence of STI in the country [9,18].To prevent and control STIs, Ethiopia has developed national STI prevention, care, and treatment strategies, programs, and guidelines.Since 2001, Ethiopia has used a syndromic approach to STI screening and treatment, which is one of the services provided [3].Despite this, the evidence from pieces of studies conducted in different geographical locations in Ethiopia has shown that STIs remain public health challenge in the country.
There is no systematic review or meta-analysis report about prevalence of STI among students in Ethiopia.In addition, systematic review and meta-analysis are needed for the results of earlier research that diverge from one another.Determining the pooled prevalence of STI and related variables among Ethiopian students is the aim of this systematic review and meta-analysis study.

Search strategy
This systematic review and meta-analysis study was undertaken following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines [19].This systematic review and meta-analysis study was registered in PROSPERO with reference ID CRD42023486676.The search strategy for this review has been done in two ways.The first was an exploration of electronic databases (PubMed, Scopus, and Google Scholar) for the presence of evidence about prevalence of STI and its associated factors among students in Ethiopia.We have used the following headings and keywords for PubMed database searching: prevalence OR magnitude AND "STI" OR "STD" AND "its associated factors" OR "risk factor" OR "determinant" OR "predictors" AND " among students in Ethiopia".Google Scholar and Scopus were conducted in line with database-specific searching guidelines using keywords used in PubMed.The second strategy was a manual search for the reference lists of the incorporated studies.We had put 2007-2023 time restrictions on our search for articles.

Inclusion and exclusion criteria
An article was eligible for inclusion if the outcome investigated should be STI and its associated factors, and the study had been conducted among students from 2007 to 2023 in Ethiopia.An article was eligible for exclusion if the publication of the article in Non-English language.

Methods for data extraction and quality assessment
The three aforementioned authors (EKB, TFA, and MGT) independently extracted the essential data from the studies included in the final analysis using a standardized data extraction template.A standardized Microsoft Excel spreadsheet was used to enter the data that had been extracted from the included research.To maintain consistency, cross-checking was done.During the extraction process, discrepancies between the extracted data were resolved through logical discussion among the three authors, and the final consensus was approved with the participation of authors ET and DE.
The table includes the author's name, the research population, the sample size, the publication year, the study area, the study design, and the evaluation tool for STI and its associated factors among students.
Utilising a PRISMA-compliant assessment form, the data from the included studies was collected [19].The Newcastle-Ottawa quality assessment scale [20] was used to rate the caliber of the research that was considered in the final analysis.This scale allows for possible scores ranging from 0 to 10.On this scale, a score of 8 or more indicated good quality, a score of 3 to 7 indicated moderate quality, and a score of less than this indicated low quality.The quality of the included studies were evaluated by two independent authors (EKB and TF) using the Newcastle-Ottawa quality assessment scale [20].The third author (ETF) discussed and resolved any disagreements.Out of the fourteen studies that were considered, ten had good quality and four had moderate quality.

Data synthesis and analysis
In this meta-analysis, we used a random-effects model to calculate the pooled prevalence of STI and its associated factors.STATA 17 was used for this meta-analysis method.Heterogeneity among the selected studies was assessed using Q and I2 statistics.Heterogeneity is absent when the I2 statistical value is zero, and small, moderate, and substantial heterogeneity are, respectively, indicated by I2 values of 25, 50, and 75% [21].
Potential heterogeneity had an impact on our study; therefore, we did a sensitivity analysis to identify its most likely source.In order to assess STI, a subgroup analysis based on sample size, publication year, and study setting had to be completed.Two tests-the ocular funnel plot test and Egger's regression test-were used to determine whether there was publication bias.P-values < 0.05 were used to define statistical significance for analyses.

Identifcation of studies
A total of 1154 papers were found during our search for literature utilizing the previously mentioned search techniques.A second search for the reference list of publications that were supported by references also turned up 7 articles, for a total of 1161 articles.Before the screening, a total of 459 articles were excluded due to duplicate records (n = 341), records marked as ineligible by automation tools (n = 78), and records removed for other reasons (n = 40).
During and after screening, a total of 249 of these articles were excluded since their publication dates were more than sixteen years in the past.A total of 431 papers were eliminated by simply reading their titles.The remaining 22 studies were thoroughly examined to see whether they should be included in the meta-analysis; however, only 14 articles [22][23][24][25][26][27][28][29][30][31][32][33][34][35] were included and the remaining 8 articles were also excluded because the outcome of interest does not directly linked with STI (Fig. 1).

Sub group analysis of the prevalence of STI among adult students in Ethiopia
Since the pooled prevalence of STI was influenced by substantial heterogeneity, a subgroup analysis has been employed based on the study setting where the study was conducted, year of publication, and sample size < or > 517.

Sensitivity analysis
To identify the source of heterogeneity that affects the pooled prevalence of STI among students in Ethiopia, we conducted a sensitivity analysis.According to the findings of the sensitivity analysis, the pooled estimated prevalence of STI obtained when every single study was excluded from the analysis was within the 95% confidence interval of the pooled prevalence of STI when all studies were fitted together.Furthermore, the sensitivity analysis result showed that the pooled prevalence of STI ranges between 4% (95% CI 3, 6) and 28% (95% CI 24, 32) when each study was left out of the analysis (Table 3).

Publication bias
The presence or absence of publication bias in the prevalence of STI was checked with two methods.The first was Egger's publication bias plot.The result from this showed that publication bias exists and that its p-value is significant (P-value = 0.0005) for STI, implying that there is significant publication bias for the prevalence of STI among students in Ethiopia.Moreover, a visual inspection of a funnel plot for a Logit event rate of prevalence of STI among students (Fig. 3) against its standard error suggests supportive evidence for the presence of publication bias.To treat publication bias, we ran a trim-and-fill analysis, however it did not account for additional studies.

Factors associated with STI among students in Ethiopia
Of all studies, only seven studies reported the factors associated with STI [23,24,26].Having multiple sexual partners [22,23,26], not use of condoms during sexual intercourses [24,26], and poor knowledge of sexually  transmitted infections [24,26] were factors significantly associated with STI.The pooled effect of three studies [23,24,26] showed that students have multiple sexual partners who were 3.31 times (AOR 3.31; 95% CI: 2.40-4.57)more likely to acquire STI in Ethiopia as compared to students who have not multiple sexual partners.The pooled effect of two studies [24,26] showed that students who did not use condoms during sexual intercourse were 2.56 times (AOR 2.56; 95% CI: 1.72-3.81)more likely to acquire STI in Ethiopia as compared to students who used condoms consistently during sexual intercourse.
The pooled effect of two studies [24,26] showed that students who had poor knowledge about sexually transmitted infections were 3.08 times (AOR 3.08; 95% CI: 1.84-5.15)more likely to acquire STI in Ethiopia as compared to students who had good knowledge about sexually transmitted infections (Table 4).

Discussion
In this systematic review and meta-analysis study, fourteen studies that were conducted between 2007 and 2023 with 7221 participants were analyzed to estimate pooled prevalence of STI, and its associated factors among students in Ethiopia.According to this meta-analysis, the pooled prevalence of STI among students in Ethiopia was 13.6%.Having multiple sexual partners, students who did not use condoms and poor knowledge about STI were significantly associated with STI.
The pooled prevalence of STI among the included studies was 13.6%, with a 95% CI of 10.2-17.This was higher than studies in South African which were 1.5% [36], east Africa, which were 8.4 [36], south east Africa, which was 1.4 [36] and among high school students in Northern Nigeria which was 9.0% [37].This difference might be due to those studies conducted in Sub Saharan Africa was rely on only laboratory investigation result instead of using syndrome diagnosis.So that laboratory confirmation results less report than syndrome approach.
Having multiple sexual partners [23,24,26] was associated with STI among students in Ethiopia.This finding is supported by findings from Ethiopian Federal Ministry of Health [38], Ethiopian Public Health Association [39] and among youth in Malawi [40].This might be because university and high school students come to a learning center from different areas to access education, they may be vulnerable to have multiple sexual partner due to peer pressure influence and financial incentives from sex seekers.This might be also due to the fact that having multiple sexual partners is one of the risky sexual behaviors that can expose individuals for the risk of contracting sexually transmitted infections including HIV/AIDS [41].Not using condoms during sexual intercourse [24,26] was associated with STI among students in Ethiopia.A high rate of not using condoms when having sex indicate that high school students had an increased risk for contracting STIs because unprotected sexual intercourse is one of the major risk factors that exposes students to STIs [38].
In this study, poor knowledge about sexually transmitted infections [24,26] was associated with STI among students in Ethiopia.This might be due to students who had poor knowledge about sexually transmitted infections engaged in early sexual activity and liable to perform unsafe sex.This in turn could result in occurrence of STIs including HIV/AIDS [42].

Strengths and limitations of the study
There are strengths and limitations to this systematic review and meta-analysis study.The employment of a predetermined search method that reduces the reviewer's bias is the first strength of the study.The study's quality evaluation and data extraction were carried out by independent reviewers, which further reduced reviewer bias.This was the study's second strength.A strength was the use of sensitivity analysis and subgroup analysis to find the source of heterogeneity.Contrarily, the heterogeneity in the study that could skew the results' interpretation is what gives birth to its limitations.Another drawback is that the validity of the estimate may be reduced by the subgroup analysis using only a small number of studies.Further more, this study included some studies that are more than 10 years old and pooled prevalence might be biased if estimates has progress over time.

Conclusion
This systematic review and meta-analysis study revealed that the pooled prevalence of STI among STI among students in Ethiopia was high.Having multiple sexual partners, not using condoms during sexual in intercourse and poor knowledge about STI were significantly associated with STI.Hence, to reduce STI among students, much consideration has to be given to modifying the associated factors by developing and strengthening sexual and reproductive health service provision in high-school and University, and by raising students awareness about STI modes of transmission, and prevention including consistent condom use through health information dissemination.Further qualitative studies are suggested to explore barrier and facilitator of STI prevention.

Implications of the results for practice, policy, and future research
The results of this systematic review and meta-analysis on STI among students have potential implications for practitioner, policy maker, and future researcher.
For practitioner: The finding of this study would be important evidence for clinical practitioners working on STI at ASRH service or youth friendly service to give much emphasis on information dissemination and counseling about STI modes of transmission, prevention including consistent condom use and risky sexual behavior including consequence of having multiple sexual partner, besides to their provision of clinical care.
For policy Maker: The policymakers and program planners would design strategies to increase knowledge of students about STI, encourage consistent condom use and discourage risky sexual behavior including having multiple sexual partner among sexually active students.
For future researcher: The high pooled prevalence of STI among students will be a motive for further qualitative research to explore barrier and facilitator of STI prevention among students in Ethiopia.

Fig. 1
Fig. 1 Flow chart for the review process *eliminated by simply reading their titles

Fig. 3 A
Fig. 3 A funnel plot for the prevalence of STI among students in Ethiopia

Table 1
Characteristics of studies on sexually transmitted infections among students in Ethiopia

Sr. no Author/year Study area Study design Sample size Out come variable % STI
CS: Cross -sectional study Fig.2A forest plot for the prevalence of STI among students in Ethiopia

Table 2
A subgroup analysis of the prevalence of STI among students in Ethiopia CI: confdence interval; DF: degree of freedom;

Table 3
A sensitivity analysis of the prevalence of STI among students in Ethiopia when each indicated studies are removed at a time with its 95% confdence interval CI: Confdence Interval;

Table 4
Characteristics of pooled associated factors with STI among students in Ethiopia