Prevalence and risk factors of intestinal parasitic infections among pregnant women in Taiz Governorate, Yemen: A hospital-based study

The World Health Organization (WHO) reported that approximately 1.5 billion individuals, about 24 % of the world’s population, are afflicted with intestinal parasites (WHO, 2020). Developing countries suffer from a high rate of parasitic intestinal infections due to poverty, illiteracy, poor nutrition, poor hygiene and unsafe drinking water (Dutta et al., 2013).

It is expected that tens of millions of pregnant women are infected with parasites, directly or indirectly affecting the mother and fetus. Neglected treatment for intestinal parasites during pregnancy can impose a considerable strain on the health of the mother, developing fetus, and newborn (Aschale et al., 2022). During any stage of pregnancy, parasitic infection can occur, but infections in the first trimester have more severe effects on the fetus and placenta. Moreover, primigravida women are more susceptible to infection than other gravida (Alula et al., 2021).

Pregnant women often contract parasitic infections due to weakened immune systems, which can profoundly affect the body’s physiological systems (Houweling et al., 2016). Furthermore, pregnant women with IPI are at greater risk of maternal complications, impaired fetal growth, low birth weight, and perinatal mortality (Mahande et al., 2016). IPIs can potentially induce anemia in several ways. Some may encourage the loss of native nutrients by damaging the intestinal mucosa, obstructing digestion, and inducing diarrhea. Loss of blood and inflammation-induced iron absorption restriction are results of G. lamblia and E. histolytica infection. Hookworms, schistosomiasis, and T. trichiura can impair nutritional intake, and decrease appetite, in addition to causing intestinal blood loss (WHO, 2023).

In Yemen, there’s no strategy or program for eradicating or controlling parasitic infections, especially during the civil war since 2014. Yemen has a high prevalence of IPI infection, and the extent of infection varies from place to place, primarily due to poor quality drinking water supply and unsanitary living conditions (Alharazi, 2022; Al-Yousofi et al., 2022). Most previous studies conducted in Yemen involving parasitic infections have focused mainly on preschoolers and schoolchildren (Alharazi, 2021; Alsubaie et al., 2016; Alwabr et al., 2016; Edrees et al., 2022). As a result, this study was necessary to assess the prevalence of intestinal parasitic infection among pregnant women in Taiz city in particular, which is not well addressed in the country as a whole. The findings would provide relevant data on the prevalence and risk factors of parasitic intestinal infection in pregnant women in Taiz governorate, serving as a springboard for the regional health office and health officers and providing baseline data for future studies.

The Ethical Committee of the Faculty of Medicine and Health Sciences at Taiz University has reviewed and approved this study. (Ref. No ECFM/04/22).

Participants in the study provided written informed consent before the study commencement. Personal hygiene and sanitation counseling were provided to study subjects.

IPIs remain a public health challenge in low-income countries such as Yemen. Designing effective intervention mechanisms for high-risk communities requires studies in different settings. According to our knowledge, this is the first study to assess the prevalence and risk factors associated with IPI among pregnant women in Yemen and Taiz city.

According to our study, the prevalence rate of parasitic intestinal infection among pregnant women in Taiz was 36.6 % which was in line with previous studies conducted in different countries, such as 36.7 % in Ethiopia (Derso et al., 2016), in northern Ghana (Ahenkorah et al., 2020) (31.7 %), and Southeastern Iran (34.2 %) (Abbaszadeh Afshar et al., 2020). In contrast, our findings were lower than those reported from Ethiopia (70.6 %) (Feleke et al., 2018), Kenya (76.2 %) (Van Eijk et al., 2009), Thailand (70 %) (Boel et al., 2010) and Venezuela (73.9 %) (Rodríguez-Morales et al., 2006). However, it was higher than 14.3 % among pregnant women in Gondar City, northwest Ethiopia (Alem et al., 2013), and 17.6 % in Ghana (Baidoo et al., 2010). There is a possibility that these differences are related to different sanitation and hygiene practices, as well as the socioeconomic statuses of the study participants.

G. lamblia was identified most frequently (12.2 %) among the parasites identified. A similar finding was found in northwestern Ethiopia (13.3 %) (Derso et al., 2016) and southeastern Iran (10.6 %) (Abbaszadeh Afshar et al., 2020). But, it was higher than those reported from Southern Ethiopia (5.4 %) (Bolka et al., 2019), Northwest Ethiopia (6.3 %) (Kumera et al., 2018) and Ghana (2.3 %) (Abaka-Yawson et al., 2020). The reason for this could be attributed to the implementation of comparable infection prevention and control measures nationwide, along with the adoption of environmental and personal hygiene practices within the community.

The prevalence rate of A. lumbricoides was 10.9 % in this study. This result is consistent with previous studies conducted in Ethiopia (10.0 %) (Buchala et al., 2022) and Nepal (11 %) (Yadav et al., 2020) but lower than previous results from Wondo Genet (24.9 %) (Bolka et al., 2019) and Mecha district, Oromia (32.7 %) (Feleke et al., 2018). On the other hand, it is higher than the findings from Felege Hiwot Referral Hospital (2.9 %) (Derso et al., 2016), Kasoa Polyclinic, Ghana (4.3 %) (Abaka-Yawson et al., 2020), and Kenya (6.5 %) (Wekesa et al., 2014). The observed differences in prevalence rates could be attributed to variations in the health service delivery systems across countries, differences in the socioeconomic status of the study participants, and variations in the study periods and designs. The prevalence of E. histolytica/dispar in this study (7.4 %) was similar to that reported in northwestern Ethiopia (7.8 %) (Derso et al., 2016). Nevertheless, it was more significant than what was reported in Wondo Genet (3.4 %) (Bolka et al., 2019) and Gondar city, northwest Ethiopia (2.9 %) (Alem et al., 2013). The high prevalence of E. histolytica in this study may be explained by using contaminated water as the leading cause of amebiasis. Most participants in our study area reported drinking from unsafe water (wells, streams, rain, dams), increasing the possibility of parasitic infections.

Our study found that the prevalence of Enterobius vermicularis was 4.3 %, which is lower than that reported in another study (6.9 %) (Kebede et al., 2022) but higher than the prevalence of 0.7 % reported in Kenya (Wekesa et al., 2014).

According to the findings of the multivariate logistic analysis, occupation (being a farmer) and the source of drinking water was found to have a statistically significant association with IPI (P < 0.05). The odds of contracting IPIs were 2.7 times greater in pregnant women who worked as farmers than those employed by the government. This finding has been supported by several studies, including those conducted by Hailu et al. (2020) and Yesuf et al. (2019), which have identified occupation (being a farmer) as a significant contributing factor to IPI. Pregnant farmers poorly understand the transmission of intestinal parasites during pregnancy. In addition, pregnant women are not regularly educated about intestinal parasite transmission. According to our study, pregnant women who drank unsafe water (rivers, wells, streams) were approximately 3 times more likely to develop IPIs than those who drank from protected tap water. This result is consistent with the previous study conducted in northwestern Ethiopia (Shiferaw et al., 2017). According to Wekesa et al. (2014), the potential infiltration of human waste from latrines into drinking water sources may be the cause.

Due to insufficient funding, the examination of fecal samples was limited to the wet mount and concentration method, which may have led to an underestimation of the prevalence of IPIs. In addition, light microscopy does not distinguish E. histolytica and E. dispar. Furthermore, the prevalence of IPIs was estimated based on one fecal sample rather than three consecutive samples, which could have resulted in an underestimation of infection levels.

A higher prevalence of intestinal parasitic infections, such as giardiasis and ascariasis, was observed among pregnant women in referral hospitals in Taiz, Yemen. It can be attributed to the participants’ farming occupation and consumption of unsafe drinking water. To address those risks, the government must implement health policies that provide health education and medical screening tests for pregnant women, particularly during their visits to referral hospitals. Additionally, ensuring access to safe drinking water not only for pregnant women but also for the entire community is essential in preventing the contraction of parasites. Furthermore, enhancing awareness of intestinal parasites among pregnant women through health education, promoting proper personal hygiene practices, and considering the co-administration of metronidazole with sulfadoxine-pyrimethamine can reduce the incidence of intestinal parasitic infections during pregnancy.