|Year : 2019 | Volume
| Issue : 10 | Page : 1341-1348
Incident HIV infection and perinatal transmission rates among HIV negative pregnant women who retested in labor in a tertiary health centre, South East Nigeria
SD Ejikunle1, II Mbachu2, C Okeudo1, E Dike1, E Ejikem3
1 Department of Obstetrics and Gynaecology, Imo State University Teaching Hospital, Orlu, Imo, Nigeria
2 Department of Obstetrics and Gynaecology, Nnamdi Azikiwe University, Nnewi Campus, Anambra, Nigeria
3 Department of Obstetrics and Gynaecology, Abia University Teaching Hospital, Aba, Abia State, Nigeria
|Date of Acceptance||16-Aug-2019|
|Date of Web Publication||14-Oct-2019|
Dr. I I Mbachu
Department of Obstetrics and Gynaecology, Nnamdi Azikiwe University, Nnewi Campus, PMB 5025, Nnewi, Anambra State
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Background: To reduce the number of new HIV infections among children, retesting of HIV negative pregnant women in labor to identify new infections and instituting appropriate modified obstetrics practices (MOP) has a huge role to play. Aims and Objectives: This study evaluated the HIV sero-positivity in labor among pregnant women who earlier tested negative in antenatal clinic, associated risk factors and the corresponding rate of mother-to-child transmission of HIV infection. Methods: This was a prospective observational study where pregnant women in labor who had earlier tested HIV negative in the antenatal clinic at Imo State University Teaching Hospital Orlu, Imo state, Nigeria, were retested. The infants of the women who seroconverted were tested for HIV infection at 6 weeks using Deoxyribonucleic acid polymerase chain reaction (DNA PCR) by collecting Dried Blood Sample. This study was conducted from October 2015 to March 2016. Result: Out of the 163 patients studied, 6 demonstrated HIV seroconversion giving a seroconversion rate of 3.7%. Deliveries from the seroconverted patients were 5 live births and 1 intrauterine fetal death. All the 5 live babies tested HIV negative at 6 weeks of age. Predictors of seroconversion in late pregnancy include spouse's HIV status and number of other sexual partners. Conclusion: Retesting of HIV negative pregnant women in labor to identify new infections and instituting appropriate modified obstetrics practices has a huge role to play in the prevention of mother to child transmission of HIV infection.
Keywords: HIV Seroconversion, labor, mother to child transmission, retesting
|How to cite this article:|
Ejikunle S D, Mbachu I I, Okeudo C, Dike E, Ejikem E. Incident HIV infection and perinatal transmission rates among HIV negative pregnant women who retested in labor in a tertiary health centre, South East Nigeria. Niger J Clin Pract 2019;22:1341-8
|How to cite this URL:|
Ejikunle S D, Mbachu I I, Okeudo C, Dike E, Ejikem E. Incident HIV infection and perinatal transmission rates among HIV negative pregnant women who retested in labor in a tertiary health centre, South East Nigeria. Niger J Clin Pract [serial online] 2019 [cited 2020 May 26];22:1341-8. Available from: http://www.njcponline.com/text.asp?2019/22/10/1341/269008
| Introduction|| |
Perinatal transmission of HIV infection is of increasing importance globally because of increase in number of women with HIV infection who are of childbearing age., The burden of mother-to-child transmission (MTCT) of HIV is higher in sub-Sahara Africa.,, This is because of high levels of hetero-sexual transmission, high prevalence of HIV in women of reproductive age group, high total fertility rate, high rate of prolonged breastfeeding and poor access to effective intervention aimed at preventing mother-to-child transmission of HIV.
More than 90% of children who acquire the virus do so before birth, during birth or through breastfeeding. MTCT prevention programs are effectively reducing child transmission among mothers with known HIV infection. Although the prevalence of HIV infection in Nigeria is 3.1%, the large population means that high proportion of people living with HIV are in Nigeria. This makes Nigeria a potential target for any strategy to reduce the global paediatric HIV disease burden.
In setting with high HIV incidence, new maternal infections may actually be responsible for a substantial proportion of the MTCT of HIV. A study from Botswana estimated that MTCT secondary to sero-conversion during pregnancy accountsfor more than 40% of all ongoing MTCT. Samson et al. advocated retesting in communities with HIV incidence of one per 1000 person-years or higher in the third trimester.
HIV is active and transmissible during the window period and may be missed by rapid antibody test kits., HIV infection acquired during pregnancy may have a worse prognosis with a higher risk of vertical transmission without any intervention., Several studies have stressed the need for a retest later in pregnancy to identify sero-converters, bearing in mind the fact that women who test negative in early pregnancy remain at risk of acquiring HIV, and also the fact that the risk of transmission to the infant is very high with new infection.,
To achieve the targets relating to PMTCT of reducing the number of new HIV infections among children to fewer than 40,000 by 2018 and fewer than 20,000 by 2020, retesting to identify new infections and instituting appropriate Modified Obstetrics Practices has a huge role to play in actualizing these lofty goals.
Different studies in developing countries have documented the existence of HIV seroconversion in late pregnancy which contributes a large proportion of MTCT of HIV infection.,,, However, most of these studies failed to evaluate the effects of Modified Obstetrics Practices on the seropositive state of the children. This study evaluated the prevalence of HIV sero-positivity in labor among all booked pregnant women who earlier tested negative in antenatal clinic in tertiary health institution, associated risk factors and the corresponding rate of mother-to-child transmission in the above patients.
| Methods|| |
This was a prospective observational study among all booked pregnant women in labor who had earlier tested HIV negative in the antenatal clinic and infants of the mothers who tested HIV positive during labor at Imo State University Teaching Hospital Orlu, Imo state in South East Nigeria. This study was conducted over a 6-month period from October 2015 to March 2016 in the labor ward of the Teaching Hospital.
The subjects were pregnant women who presented to the labor ward of the Teaching Hospital and their infants. This included booked pregnant women in labor who earlier tested negative in the antenatal HIV routine testing and counseling (HTC) at booking and who consented to the study. All pregnant women who withheld consent, pregnant women who were HIV positive from the initial antenatal HIV HTC, known HIV clients and pregnant women who presented in labor but whose initial HIV screening was done outside our facility were excluded from the study.
Ethical clearance was obtained from the institution's ethics committee and all the participants gave an informed consent. The study was conducted according to Helsinki's declaration on studies involving human subjects.
Sample size determination
This was determined using the formula n = z 2 pq/d2
Where n = sample size, z = standard normal deviation set at 1.96 for 95% confidence interval, P = prevalence of HIV among pregnant women attending antenatal care at the study site = 8.2%, q = complimentary probability of P = I-P (degree of accuracy or precision = 0.005), d = degree of accuracy or precision level = 0.05. n = 156. Accepting a non-response rate of 4%, the calculated sample size was 163.
Patients who met the inclusion criteria and gave consent were recruited consecutively in the labor ward until the number of the sample was reached. The recruitment was from Monday to Sundays every week for the period of the study.
Data was collected with self-administered confidential semi-structured questionnaires. The coded questionnaires also had provision for recording the test results. The relevant variables collected include the age, occupation, parity, marital status, sexual and social practices of subject and her partners. Others include risk factors for transmission of HIV. Statistical analysis of the result was done using SPSS version 20.0. There were cross tabulations to explore relationships between variables. The level of statistical significance was set at P value 0.05 providing 95% confidence interval.
The medical folders of antenatal women who presented in labor were scrutinized daily in the labor ward to select those who met the inclusion criteria. Counseling of the women about the study was done.
Maternal HIV retesting
The researcher and HIV adherence counselors carried out pre-test counseling and thereafter the questionnaires were filled. Following consent, all booked pregnant women in labor who earlier tested negative in the antenatal HIV routine testing and counseling at booking clinic had about 3mls of venous blood collected using disposable syringe and hypodermic needle by the researcher or any of the research assistants. The blood was immediately emptied into an ethylenediaminetetraacetic acid (EDTA) bottle that was coded to match the subject's questionnaire for easy identification.
The collected blood sample was used to perform a repeat HIV screening. Serial rapid HIV testing algorithm was done with Determine (Alere Japan), Uni-Gold (Trinity Biotech Ireland) and Statpak (Chembio Diagnostic Systems, Inc, USA) rapid test kits as appropriate. Determine test kit was used for screening and the positive samples were confirmed using Uni-Gold test kits while STATPAK test kit served as the tie breaker.
Interpretation of the test
Reactive test is a test with two lines of any intensity in both the control and test areas while non-reactive test is made when one line appeared in the control area, and there was no line in the test area. The test is adjudged invalid test when no line appeared in the control area. Invalid results were not reported. Test was repeated with a new test kit device even if a line appeared in the test area.
| Disclosure of Result|| |
Subjects that tested positive with the serial rapid test algorithm were diagnosed as being HIV positive. The client was informed about a negative result in an individualized post-test counseling session that was undertaken by the researcher. Those with positive repeat HIV testing had post-test counseling including infant feeding options. In postpartum, the discussion on the disclosure of the result were made as well as partner and family testing.
Modified obstetrics practice and management of pregnant women who retested positive to hiv in labour.
The parturients were commenced on highly active antiretroviral therapy (Zidovudine, Nevaripine and Lamivudine). Labor monitoring, delivery and postpartum were conducted with standard practice and techniques to reduce MTCT of HIV.
These include limiting the number of vaginal examinations, use of partograph to avoid prolonged labour and delay of artificial rupture of membrane. Cutting the umbilical cord under gauze cover and bathing the neonate with water and antiseptic liquid (chlorhexidine gluconate). Neonatal antiretroviral prophylaxis with Nevirapine was instituted in conjunction with the neonatologist.
Infant HIV diagnosis: Determination of the HIV status of the exposed infant was done in accordance with National Guideline for PMTCT 2014. All HIV exposed infants were tested for HIV using DNA PCR by collecting the dried blood sample (DBS) at the age of 6 weeks. The collected blood samples were sent to the IHVN Polymerase Chain Reaction (PCR) laboratory in Nnamdi Azikiwe University Teaching Hospital, Nnewi, Anambra State for processing. Neonatal antiretroviral prophylaxis with nevirapine was instituted for all exposed neonates in conjunction with a neonatologist/infectious disease pediatrician until diagnosis was made at six weeks which was the evaluation point in this study. However, further infant management, evaluation and testing was done in Pediatric outpatient clinic of our hospital following an appropriate referral system and was guided by result outcome in accordance with National Guidelines for PMTCT of HIV 2014.
Results validation and interpretation
HIV-1 DNA detected: when HIV-1 OD > 0.8 (regardless of IC OD)
HIV-1 DNA not detected: when HIV-1 OD < 0.2 and IC OD > 0.2
Invalid: when HIV-1 OD < 0.2 and IC OD < 0.2, needed retest
Indeterminate: when HIV-1 OD was between 0.200 and 0.800, and/or if HIV-1 + sample was in a well next to a positive control or if a new HIV-1 + sample was next to a well with a previously known HIV + sample, needed retest.
Retesting: If retesting was required, duplicate repeat testing was performed on the processed specimen. The final interpretation of these specimens was determined using 0.2 cut off.
When invalid result (i.e. HIV-1 OD < 0.2 and IC OD < 0.2), re amplification and re-detection were performed. If still invalid, a different DBS vial was processed and tested. When sample was a valid 'negative' i.e. a whole blood DNA PCR or plasma RNA PCR came up as positive, then original extract retested. When still negative, another punched disk was retested from the same sample. If the sample was still negative it was reported as HIV-1 DNA not detected.
- Specimens were reported as HIV-1 DNA detected or HIV-1 DNA not detected.
- Report form was prepared and sent to molecular monitoring team for review.
- When approved, results were sent back to researcher either as an electronic or hard copy.
Disclosure of infant hiv status result and subsequent management:
All the mothers whose infants tested negative where given further counselling. Those who were breastfeeding were encouraged to continue the HAART therapy and the infants were to be tested after cessation of breastfeeding.
| Results|| |
The mean age of the women was 29.1 years (SD = 4.2). 65 (39.9%) of the women were in the age category of 25-29 years. 22 (13.5%) were within 20-24 years, 1 (0.6%) was below 20 years while 3 (1.8%) were above 40 years of age. Majority of the women, 99 (60.7%) had secondary education, 5 (3.1%) had primary education while 56 (34.4%) had post-secondary education. 3 of the subjects (1.8%) had no formal education. A greater percentage, 156 (95.7%) were currently married while 2 (1.2%), 1 (0.1%) and 4 (2.5%) were separated, widow and single, respectively. 90 (55.2%) of the women were multiparous, 12 (7.4%), 14 (8.6%) and 47 (28.8%) were grand multiparous, primigravida and primipara, respectively. [Table 1] shows the socio-demographic characteristics of the women.
163 pregnant women participated in this study. The number of HIV seroconversion was 6 of the 163 subjects that participated in the study which gave a HIV seroconversion rate of 3.7%. Deliveries from the seroconverted patients were 5 live births and 1 intrauterine fetal death. All the 5 live babies tested HIV negative with HIV DNA PCR test at 6 weeks of age.
[Table 2] shows the association between sociodemographic characteristics and HIV seroconversion in labor. Age range 20-24 accounted for the highest repeat HIV seroconversion rate 3/6 followed by 30-34 (2/6). 150 women were currently married accounting for the 2/6 of HIV seroconversion while 4/6 were single which accounted for 66.7% repeat HIV seroconversion.
|Table 2: Association between Sociodemographic Characteristics and HIV Seroconversion in Late Pregnancy|
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[Table 3] shows the association of HIV repeat seroconversion in labor with selected partner's factors: The partner's factors that had significant relationship with retesting seroconversion include HIV status of the partner and number of other sexual partners. The patients' factors which significantly correlated with seroconversion include numbers of sexual partners greater than 2, sex for money and past history of STI. Blood transfusion, alcohol intake, anal sex, use of barrier method of contraception were not significantly associated with increased repeat HIV seroconversion rate. This patient factors are as shown in [Table 4]. The flow diagram is shown in [Figure 1].
|Table 3: Association of HIV seroconversion in Late Pregnancy with selected Partner's factors.|
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|Table 4: Association of HIV seroconversion in late pregnancy with selected Patient's factors|
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| Discussion|| |
The number of HIV seroconversion was 6 of the 163 patients that participated in the study. This translates to HIV seroconversion rate of 3.7%. Deliveries from the seroconverted patients were 5 live births and 1 intrauterine fetal death. All the 5 live babies tested HIV negative with HIV DNA PCR test at 6 weeks of age. Correlates of seroconversion in late pregnancy include marital status, number of sexual partners and past history of sexual transmitted diseases. Others are the partners' HIV status and number of other sexual partners.
HIV seroconversion prevalence of 3.7% among the antenatal attendees who were previously HIV sero-negative earlier in pregnancy observed in our study conforms with the CDC's cut off >(1.2%) for high risk populations. It is comparable with the 3.9% sero-conversion rate found by Umeononihu et al. at Nnewi, South East Nigeria. It is higher than the 2.3% and 2.2% HIV seroconversion rate found by Afolabi et al. at Ogbomoso, South West Nigeria and Qolohle et al. at Durban Southern Africa among antenatal attendees, respectively., Lower rate of 1.2% and 0.25% were recorded at Abuja and Benin both in Nigeria., A Russian study recorded 0.4% seroconversion rate among pregnant women with previous HIV seronegative results. The relative similarity of the repeat HIV seroconversion prevalence with that of Nnewi study may be due to similarity of the socio-demographic characteristics of the subjects. Like in their study, majority of the patients in this study were Igbo (96%) and young (modal age: 25-29).
The differences with findings from other studies may be due to varying socio-demographic characteristics of the subjects, the prevalence and accuracy of testing and associated risk factors.,,
One of the strengths of this study was the prospective follow up and testing of the infants of mothers that seroconverted in late pregnancy. Previous studies in Nigeria at Ogbomoso and Nnewi missed the excellent opportunity of determining the impact of the interventions aimed at PMTCT of HIV infection.,
This study further documented that all the babies of the patients with HIV seroconversion in labour were HIV negative at 6 weeks postpartum with DNA PCR testing. This confirms the excellent opportunity provided by repeat HIV screening in labor for prevention of mother to child transmission of HIV infection especially in developing countries with high disease burden. This suggests that a reliable HIV testing during labor provides a critical opportunity for administering appropriate interventions to prevent mother-to-child transmission of HIV.
The importance of this study is obvious when compared to a retrospective study by Kendall et al., where approximately 11% of infants whose mothers seroconverted during pregnancy were infected with HIV. This may be as a result of lack of PMTCT interventions during labor and puerperium in those women. It is also consistent with findings by retrospective study by Sagay et al. in Jos Nigeria. Similarly, Drake et al. in a systematic review and meta-analysis on the incident HIV during pregnancy and postpartum and risk of mother-to-child, showed that MTCT risk was significantly higher among women with incident HIV during pregnancy who did not benefit from appropriate MTCT preventive measures. Their study showed that MTCT risk was significantly higher among women with incident HIV during pregnancy who did not benefit from appropriate MTCT preventive measures. Afe et al. in a case series reports on HIV sero-conversion among pregnant and breast-feeding mothers and the risk of vertical transmission of HIV in Nigeria noted that three out of the five babies whose mothers seroconverted were HIV infected as confirmed by HIV DNA PCR test. These three babies could not benefit from the intervention for PMTCT because the mothers had the repeat HIV test in late postpartum.
The 0% rate of PMTCT of HIV among these women who seroconverted in late pregnancy in our study is strongly linked with the modified obstetrics practice instituted during delivery, use of HAART for the women, PEP for the infants and safer infant feeding.
Correlates of seroconversion in this study include women who were not currently married, who had sex for money or had multiple sexual partners during the period of pregnancy and past history of STI which is comparable to other studies., Other correlerates include women whose partners were HIV positive or had multiple sexual partners. This group of high risk people should be targeted in any strategy for PMTCT and retesting in late pregnancy.
The high repeat HIV sero-prevalence is unacceptable because it implies that for every 27 women that screens HIV negative early in the antenatal period, one woman will likely turn positive in late pregnancy. It is difficult to say from the design of this study whether these are new infections or purely true sero-conversion. Nonetheless, the obvious fact is that a single HIV screening in early pregnancy for antenatal attendees in our environment is inadequate and definitely leads to true missed prevention opportunity because these women had availed themselves of antenatal care and testing.
Despite the obvious strength of our study, it also has some limitations. We did not evaluate the infants' HIV status at 18 months. However, it is not expected to be different since all the babies received artificial infant feeding. In addition, recruiting the women earlier at booking may have made the study more robust.
| Conclusion/recommendations|| |
The findings from this study support routine HIV retesting in labor for pregnant women who are HIV seronegative in early pregnancy. This will help in the implementation of prevention of mother to child measures like modified obstetrics practice for those who are HIV positive and appropriate post exposure prophylaxis for their infants.
Further studies to determine the reasons for seroconversion will be of immense value so that cost-effective preventive measures will be applied especially in developing countries with very high disease burden. Multicenter community based researches are recommended in view of the interventional benefit in this study to determine whether the new infections were cases that seroconverted or new infections that developed during the latter part of the pregnancy.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4]