Seroprevalence of human cytomegalovirus among pregnant women who had undergone abortion(s) attending El-Damazin Hospital for Obstetrics and Gynecology, Sudan: A cross-sectional study

Introduction

Cytomegalovirus (CMV) is the most ubiquitous member of the herpes virus family. Human cytomegalovirus (HCMV) is the most common cause of congenital malformation resulting from viral intrauterine infection in developed countries¹. CMV infects a high percentage of individuals during their life and after recovery of disease it hides in leukocytes. Although this virus is not considered as hazardous to health, in pregnant women it is a major factor that threatens the health of neonates². Primary CMV infection occurs in 0.15%–2.00% of all pregnancies and may be transmitted to the fetus in 40% of cases³.

Seroprevalence of HCMV in adults ranges from 55% in developed countries to as high as over 90% in developing countries like China⁴. In Sudan, age is significantly associated with CMV IgM detection, and history of miscarriage was associated with CMV IgG positive women⁵. Additionally in Sudan, a study conducted in 2013 by Elamin and Omer at Khartoum Teaching Hospital reported the seroprevalence rate among pregnant women with recurrent abortion as 55.3% and 3.2% for HCMV IgG and IgM antibodies, respectively⁶. Another recent study in Sudan conducted at Omdurman Maternity Hospital reported a sero-frequency rate of HCMV among pregnant women as 74.4% for CMV IgG and 14.4% for HCMV IgM⁷.

HCMV can produce maternal infection and exhibits a high tropism for cervical mucosa and is considered as the most implicated virus in recurrent spontaneous abortion (RSA)⁸. Many pregnant women in Blue Nile State, Sudan, have suffered from recurrent pregnancy loss, and currently there is no available data concerning the prevalence of HCMV in Blue Nile state; therefore, this study aimed to determine HCMV antibodies (IgG and IgM) among pregnant women, who had undergone abortion(s) in this state.

Methods

Results

A total of 270 women were enrolled in the study. The majority of the women were aged between 26 and 40 years. Low socioeconomic status was recorded in 84.8% (229/270) of participants, and illiteracy and women obtaining primary education was observed in 80% of participants. Most women were observed to be in the first trimester of pregnancy (85.5%; 231/270) (Table 1). In total, 27.8% (75/270) of the women had a history for 1-7 abortions, while 72.2% (195/270) had no history.

The seroprevalence of HCMV IgG and IgM among the 270 women was 74.8% (202/270) and 13.3% (36/270), respectively (Figure 1).

Figure 1. Sero-prevalence of HCMV IgG and IgM among 270 aborted pregnant women.

HCMV IgG detection was significantly correlated to socioeconomic status and gestation stage, but was not correlated to age group and education level (Table 2).

Discussion

CMV is globally distributed, with 40–100% of the global population positive for CMV antibodies^10,11, particularly among low economic individuals¹². In Sudan, there are only a few published data (Western and Central Sudan, and Khartoum) concerning epidemiology of HCMV among pregnant women. In our study area, which it located in the South of Sudan, there are no findings about the seroprevalence of HCMV in pregnant women who have had abortions.

The relationship between seroprevalence of HCMV and socioeconomic and education level among the present study population is significant, which may explain poor health status and susceptibility to certain diseases. Numerous studies have evaluated socioeconomic and education level for seroprevalence of HCMV, and most of these studies confirm the strong association between the socioeconomic disparities and high seropositivity^13–17

HCMV IgG level in this study was significantly correlated to abortion in the 1^st trimester gestation, which has also been shown by other studies^1,18. HCMV infection is considered a significant public health problem because it can cause disease in those with weakened immune systems, which has been confirmed by a study in Sudan in which a high frequency (98.3%)of seroprevalence of HCMV among pregnant women was reported¹⁹.

In the present study, the sero-prevalence of HCMV among the participants was 74.8% for IgG and 13.3% for IgM; these findings are in total agreement with another study in Sudan among pregnant women⁷, but is in contrast to other study in Iran in which the frequency for HCMV IgG and IgM was 14.28% and 28.25%, respectively²⁰. Larger and smaller frequencies of HCMV IgG level have also been reported in Egypt²¹ and Iran²², respectively. The IgM level found in this study is similar to findings reported in Poland (13%) by Fowler and Boppana²³, and similar results were obtained by other authors in Iraq²⁴ and India²⁵. Higher results have been reported in Egypt (32.6%) for HCMV IgM¹⁸, and lower results have been reported in Turkey²⁶ and Korea²⁷ (1% and 1.7%, respectively). Many factors may contribute to HCMV transmission and prevalence, such as socioeconomic and lifestyle factors, and it should be notes that most immunocompetent carriers of HCMV remain asymptomatic²⁸

In this study, 11.9% of the study population revealed primary infection with HCMV, i.e. positive results for both IgG and IgM. This frequency is larger than that recorded previously in a hospital in Khartoum²⁹.

Conclusions

Seroprevalence of HCMV in Blue Nile State, Sudan, among pregnant women who had undergone abortion(s) was 74.8% for IgG and 13.3% for IgM. HCMV prevalence in pregnant women -was most prevalent for women in the first trimester- with low economic status.

Data availability