PREVALENCE OF TRICHOMONAS VAGINALIS AND HIV CO-INFECTION AMONG ASYMPTOMATIC PREGNANT WOMEN IN ZARIA, NORTHERN NIGERIA
Background: Trichomonas vaginalis is the most common curable sexually transmitted infection worldwide. Serious adverse reproductive health outcomes including pregnancy complications, pelvic inflammatory disease, and an increased risk of HIV acquisition have been linked to Trichomonas vaginalis infection.
Objective: To determine the prevalence of Trichomonas vaginalis in asymptomatic pregnant women and their HIV status in Ahmadu Bello University Teaching Hospital Zaria, Northern Nigeria.
Methodology: A prospective cross-sectional descriptive study, using a proforma to obtain demographic and reproductive health information from consenting pregnant women attending antenatal clinic. Vaginal swab and blood samples was taken and analysed for Trichomonas vaginalis and HIV respectively. Data was analysed using SPSS V17 with p value of significance was set at 0.05.
Results: The overall prevalence of Trichomonas vaginalis was 19.2%.There was an inverse relationship between the level of education and acquisition of Trichomonas vaginalis infection in pregnancy; women having no formal education had a higher prevalence of the Trichomonas vaginalis infection (7.5%) as against those who had tertiary education (1.7%). The 26- 30 years age group had the highest prevalence of both HIV infection (5.0%) and Trichomonas vaginalis infection (5.8%); strongly suggesting the possibility of co-infection between the two agents. There was a statistically significant association between Trichomonas vaginalis infection and HIV infection with a P value of 0.0003. The relative risk of acquiring HIV in the presence of Trichomonas vaginalis infection was 4. (RR 4.193 confidence Interval 1.756-10.01).
Conclusion: Improvement of the socioeconomic status and education of women especially sexual health; will reduce the prevalence of Trichomonas vaginalis and HIV co-infection.
Keywords: Pregnancy, Trichomonas vaginalis, HIV infection
Trichomonas vaginalis has continued to cause serious adverse reproductive health outcomes including pregnancy complications, pelvic inflammatory disease, and an increased risk of HIV acquisition1 The magnitude of social and economic consequences of sexually transmitted infections (STIs) in developing countries has made it a major public health problem. 2, 3 STIs are also found in pregnant women and the prevalence is higher in Africa causing significant maternal and perinatal morbidity. 3-5
Trichomonas vaginalis is a unicellular flagellate protozoan organisms that cause STI.6 Many STIs including those due to Trichomonas, can be transmitted to the fetus via transplacental spread or by passage through the birth canal and via lactation to the neonate. 6 Sexually Transmitted Infections (STIs) and other Reproductive Tract Infections (RTIs) have been associated with a number of adverse pregnancy outcomes which includes abortion, stillbirth, preterm delivery, low birth weight, postpartum sepsis, neonatal pneumonia, neonatal blindness & congenital infection. 2-5, 7 Recent research has shown that having one untreated STI increases the risk of contracting another potentially more dangerous one, like Human Immunodeficiency Virus (HIV) infection if there is exposure. 8, 9Trichomoniasis in pregnancy has been reported to impacts adversely on birth outcomes and is also a co-factor in Human Immunodeficiency Virus (HIV) transmission and acquisition. 10, 11
Clinical infection with Trichomonas vaginalis in the neonate is an unusual occurrence and has been reported in a two weeks old girl child presenting with vaginal discharge with complete resolution to metronidazole treatment.12 Due to high frequency of the infection during pregnancy and the development of metronidazole-resistant isolates, therapeutic alternatives to 5-nitroimidazole are being searched like Triterpenes; which are natural products presenting several biological activities such as anti-protozoal activity.13
The prevalence of Trichomonas vaginalis infections are typically underestimated due to poor sensitivity of diagnostic tests.6 However, the World Health Organization (WHO) quoted the overall prevalence as 3.1%.6, 14 In Nigeria the prevalence observed in an Enugu study was 6.9%; 15 4.7% was seen in Ilorin16 and 29.8% in Lagos.17
In the sub-Saharan Africa, including Nigeria, Trichomoniasis has neither been the focus of intensive study nor of active control programs, and this neglect is likely a function of the relatively mild nature of the disease. 18 This study explored the rate of Trichomonas infection in pregnancy as well as the level of co-infection with HIV with a view to adding to the growing body of literature and suggests control measures.
This was a cross sectional study which was conducted over a three month period. Questionnaires were used to obtain the socio-demographic and reproductive profile from consenting clients who were attending antenatal clinic for the first time in their current pregnancy at the Ahmadu Bello University Teaching Hospital, Zaria, Northern Nigeria. High vaginal swabs and blood specimens for both Trichomonas vaginalis and HIV were obtained and analysed. The data obtained was analyzed using Statistical Package for Social Science (SPSS) Version 17.0 for windows. The level of significance was considered to be p-value <0.05. The level of association between Trichomonas vaginalis and HIV infection was determined using the Epi-Info software.
A total of 120 women consented for the study. The socio-demographic and obstetric characteristics of the patients are as shown in Table 1.0. The mean age was 28.5 + 2.3years, mean gravidity was 3.5 and 20 weeks was the average gestational age at booking.
The overall prevalence of Trichomonas vaginalis was 19.2%. The 26-30 years age groups having a value of 5.8% which was closely followed by age group 21-25years with 5.0%. The lowest prevalence was found at age group 36-40years.
Low level of education is shown to have a positive impact on the acquisition of vaginal Trichomonas vaginalis. Clients having low level of education had a higher prevalence of the Trichomonas vaginalis; 7.5% was seen in those with Koranic (non-formal) education. The prevalence was however lowest in those who had tertiary education 1.7%.-
The highest prevalence was seen in clients who were housewives (10.5%); students and civil servants had the lowest prevalence of 1.7% and 2.5% respectively.
Mutigravidae are more likely than primigravidae to have Trichomonas vaginalis infection (15.0% vs. 4.1%). The prevalence was observed to be highest in the second trimester (10.8%) as compared to the first and third trimester which were 5.0% and 3.3% respectively.
The frequency distribution of HIV status in the study population among the consenting client is shown in Table 2.0. Sixteen out of 98 were positive for HIV giving a prevalence of 16.3%. Figure 1.0 shows the percentage distribution of HIV by client’s age group. It was observed that HIV was more prevalent in age group 26-30years (5.0%) and was least prevalent in the older age group of 36-40years (0.8%). The relationship between the occurrence of Trichomonas vaginalis and HIV infection is shown in a two by two table (Table 2.0).
The prevalence of Trichomonas vaginalis found in this study was 19.2%. The World Health Organization quoted a prevalence of between 3.0- 3.1%6, 14, 19, but added that there was under reporting of the infection. Prevalence rates as high as 29.8% was found in Lagos, Nigeria 17 16.0% was seen in Mwanza, Tanzania20 and a lower rate of 4.7% and 6.9% were found in Ilorin, Nigeria 16 and Enugu, Nigeria15 respectively. A prevalence of 3.7% was seen in a study in Togo.21 Our result compares with that of Tanzania.
In the age related prevalence, the study showed a steady increase in prevalence between ages of 16 to 30years, with the highest rate of 5.8% occurring in the age group 26-30years. This may suggest an increasing sexual activities along the age line considering the fact that Trichomonas vaginalis is sexually transmitted. This can also probably explain the decline in prevalence in the older age group with lowest rate of 0.8% at age group 35-40years. There is however a slight variation with the Enugu study which found the highest age related prevalence of 3.7% among the age group 20-25years.
There was an inverse relationship between the level of education and acquisition of Trichomonas vaginalis infection in pregnancy; women having no formal education had a higher prevalence of the Trichomonas vaginalis infection (7.5%) as against those who had tertiary education (1.7%). This was consistent with findings in Enugu and Ilorin where low level of education was associated with Trichomonas vaginalis infection. Formal education is associated with improvement in personal hygiene and sexual behavior.
The prevalence of Trichomonas vaginalis was highest among housewives and least among students; this was unlike the Enugu study that found the highest prevalence to be among the business group. The sociocultural backgrounds of the two environment relatively differs and the lack formal education among housewives in our environment can be a predisposing factor to the acquisition of Trichomonas vaginalis infection.
There appears to be a relationship between parity, trimester of pregnancy and infection with Trichomonas vaginalis. Previous pregnancies was recorded in the literature to be a risk factor.10 This study showed a higher prevalence rate among the multigravidae as compared to primigravidae. The prevalence was highest in the second trimester of pregnancy as compared to other trimesters. This findings was similar that of Cotch et al4 in their study of vaginal infections and prematurity; where Trichomonas vaginalis infection was commonest in mid gestation. The mean age at booking was 20 weeks showing that most women were seen in the second trimester when Trichomonas vaginalis infection was more likely to be present.
The prevalence of HIV infection in this study was 16.8% which was higher than the national average of 3.4% and Kaduna state average of 9.2%. 22 This may be explained by the fact that most of the clients were in their reproductive years and the Ahmadu Bello University Teaching Hospital, Zaria was a major referral center for the Prevention of Mother To Child Transmission (PMTCT) of HIV in Northern Nigeria.
Both HIV and Trichomonas vaginalis infection were highest in the age group 26-30 years; this was strongly suggestive of the possibility of co-infection between the two agents. There was a statistically significant association between Trichomonas vaginalis infection and HIV infection with a P value of 0.0003. There was a four times relative risk of acquiring HIV in the presence of Trichomonas vaginalis infection (RR 4.193 confidence Interval 1.756-10.01).
CONCLUSION AND RECOMMENDATIONS
Routine screening for STIs like Trichomonas vaginalis during antenatal period should be the standard of care because of its proven benefits on the outcome of pregnancy. Metronidazole which is the treatment option when found, is a cheap, readily available and safe in pregnancy. Additionally, screening for HIV co-infection will add value to healthcare services in the antenatal clinic.
Improvement of the socioeconomic status and formal education in women especially sexual health and lifestyle modification is likely to reduce the prevalence of Trichomonas vaginalis and HIV co infection.