Introduction

Cytomegalovirus (CMV) was first described in 1881 when large cytoplasmic inclusion (protozoan-like cells) were seen in the kidney of a still-born infant. The term cytomegalia was introduced in 1921, but the viral aetiology of the disease was confirmed in 1926. CMV is the leading cause of congenital viral infection in developed countries, occurring with a stable incidence of 0.4 to 2.2% of all live births ¹.

Human cytomegalovirus is an enveloped double-stranded DNA virus ¹, ²., a potential killer or a life long silent companion. It is the most common congenital virus in the world ³. Both primary and recurrent infections can result in foetal infection. The signs of the disease include encephalitis, deafness, haematological disorders, neurological abnormalities, hepatomegaly, splenomegaly, Jaundice, periventricular calcification, choriorentinitis and death ³, ⁴, ⁵, ⁶, ⁷. Congenital CMV infection is described in 30,000 to 40,000 newborns each year in United States. Approximately 9,000 of these children have developed permanent neurological sequelae. The death rate of symptomatic congenital human CMV infection is placed at approximately 30% ³. The screening of newborn infants has been recommended to help in identifying infants at high risk. Seroprevalence of CMV has been documented in many countries including Finland ⁸, ⁹, ¹⁰, ¹¹. This work was aimed at determining the seroprevalence of HCMV among pregnant women with the objective of creating awareness for its prevention among high risk group in Nigeria.

Materials And Methods

Study Population

Study Design

Age

Gestational Age

Gravidity

Ethical Considerations

Collection of Specimen

Analysis of Specimen

Data Management

Results

Out of the 253 blood sample collected, 213 (84.2%) were positive for CMV antibodies. The age bracket 21-25years had the highest prevalence of 79(31.2%) reactivity to HCMV followed by the 26 – 30 years age group which showed a prevalence of 58 (22.9%) (Table 1).

Distribution of HCMV infection in relation to gravidity, Multigravidae were more often infected, (86.1%) than primigravidae (77,1%).

Non-health workers have shown a higher prevalence (84.6%) of HCMV antibodies in their sera as compared to health workers (25.0%) in (Table 2).

Table 3, depicts the distribution of HCMV antibodies in pregnant women according to age. Teenage pregnant women were more infected (87.5%), followed by elderly pregnant women (84.2%) and adult pregnant women (83.5%).

The prevalence of HCMV infection in pregnant women in relation to gestational age is shown in (Table 4). Pregnant women in their second trimester showed the highest seroprevalence (86.2%) of HCMV antibodies followed by third trimester category of 75.9%.

Figure 1

Table 1: Distribution of HCMV infection by age groups ( years)

Figure 2

Table 2: Distribution of HCMV antibodies among health and non health workers

Figure 3

Table 3: Age variations of HCMV antibodies among patients screened

Figure 4

Table 4: Prevalence of HCMV antibodies in relation to gestational age

Discussion

The prevalence of CMV antibodies among women varies with geographical location, socio – economic status and occupation ¹. One of the most important aspect of the epidemiology of the virus is its extreme high prevalence in both developed ¹⁵, and developing countries ¹¹.

This study showed a seroprevalence of 84.2% among pregnant women in Bida, Nigeria. This is on the high side compared to previous reports of 70.7% and 77.5% prevalence in Finland and Japan ⁸, ⁹ and lower than the work done by ¹⁰, ¹¹ with prevalence of 91.05% and 96.0% in India and Egypt respectively. Racial difference between the populations, enormous cultural and economic difference between developed countries (where the study was previously carried out) and developing countries like Nigeria (Bida) are valid factors that might be responsible for this occurrence as also reported by ¹³, ¹⁴. From the results obtained in this study, the prevalence of CMV is high between ages group 21 – 30 years when compared to other age groups. This trend could be attributed to the fact that age group 21 – 30 years represents active and the sexually – matured youths with the tendency toward sexual promiscuity and its resultant likelihood of high infection rates ¹⁶.

Seroprevalence of primigravidae and multigravidae subjects might be due to anticipated increase in sexual activity as a result of longer periods of marriage among the multigravidae than in most primigravidae. Further more multiple sexual partnership could be responsible for this trend. This could be supported by previous studies where sexually transmitted infection shown to be higher among promiscuous people having sexually transmitted diseases 2, 13.

There was an increase in HCMV seroprevalence with gestational age from first trimester to second trimester in third trimester which could be due to recovery of depressed immunity.

Acknowledgements