Deoxyribonucleic Acid-Polymerase Chain Reaction Status of HIV Exposed Infants in a Sub Regional Prevention of Mother-to-Child Transmission of HIV Programme during the Period 2009-2020

Elon Warnow Isaac^1,2, Ayomikun Ajani³, Jalo Iliya¹, Mohammed Manga^2,4, Abubakar Joshua Difa^2,5, Oyeniyi Christianah Oluwaseun², Muhammad Danlami Hassan⁶

¹Department of Paediatrics, College of Medical Sciences, Gombe State University, Gombe, Nigeria.
²Infectious Disease Training and Research Group Gombe, Gombe, Nigeria.
³Kettering General Hospital University Hospitals of Northamptonshire, Kettering, United Kingdom.
⁴Department of Medical Microbiology, College of Medical Sciences Gombe State University, Gombe, Nigeria.
⁵Department of Community Medicine, College of Medical Sciences Gombe State University, Gombe, Nigeria.
⁶Department of Molecular Microbiology, Federal Teaching Hospital Gombe, Gombe, Nigeria.

DOI: 10.4236/ojepi.2023.134024                

Abstract

Introduction: Transitioning to more efficacious Antiretrovirals for HIV infected pregnant women and infant prophylaxis has reduced Mother to child transmission of HIV significantly. This study aimed to determine HIV infection status in HIVexposed infants who had their first DNA polymerase chain reaction test in our molecular Laboratory. Subjects, Materials and Methods: Dried Blood Spots for HIV DNA results from 5 states between 2009 and 2020 were analyzed in the PCR laboratory of the Federal Teaching Hospital, Gombe. Results: Nine thousand eight hundred and twenty-three Human Immunodeficiency Virus Deoxyribonucleic acid polymerase Chain Reaction results were analysed; 4937 (50.2%) were males. During the study period, there was an overall declining trend in the mother-to-child transmission rate from 3.8% in 2009 to 1.0% in 2020. 6120 (62.3%) of HIV + mothers received Highly active antiretroviral therapy HAART before pregnancy. 7845 (76.2%) of the infants received Nevirapine prophylaxis. Dried blood spot samples were collected from 4077 (41.5%) at 6 - 8 weeks. 8438 (85.9%) received cotrimoxazole. 9469 (96.4%) were ever breastfed. Of the 9823 HIV DNA PCR results, 255 (2.6%) were positive while 69/4077 (1.7%) and 109/2662 (4.1%) were positive for HIV DNA at 6 - 8 weeks and > 12 weeks respectively. (p = 0.001). 86/747 (11.5%) of infants whose HIV-positive mothers received no ARVS were HIV DNA positive. (p = 0.001). 106/884 (12.0%) of infants who had no Antiretroviral prophylaxis had positive HIV DNA results; 7/413 (1.7%) with Zidovudine/Nevirapine prophylaxis had positive results. (p = 0.001). 246/9469 (2.6%) of infants that were ever breastfed were positive for HIV DNA; 11/354 (3.0%) that never breastfed had positive HIV DNA. Conclusion: Lack of maternal/infant ARVs and prolonged breastfeeding increased the risk of infant HIV infection.

Keywords

Mother to Child Transmission of HIV, Antiretrovirals, HIV Exposed Infants, Deoxyribonucleic Acid Polymerase Chain Reaction, Early Infant Diagnosis

1. Introduction

Nearly all young children newly infected with HIV are infected through mother-to-child transmission (MTCT); about 86% of the estimated 160,000 children newly infected with HIV in 2018 were in the WHO African Region. [6] With a PMTCT of HIV coverage of 46%, Nigeria harbours about 27 % of the global burden of mother-to-child transmission of HIV and is one of UNAIDS’s 23 priority countries for PMTCT. [7] There is geographic disparity in PMTCT of HIV coverage among states and within regions in Nigeria. [8]

Early infant diagnosis uses Dried blood spot samples of HIV-exposed infants to detect HIV-DNA using the polymerase chain reaction technique in infants postpartum. Early Infant Diagnosis facilitates early linkage of HIV-infected infants to treatment care and support. [9] [10] Early initiation of antiretroviral therapy (ART) in the first 3 months of life reduces early infant mortality by 76% and HIV disease progression by 75%. [11] Globally, in 2018, only an estimated 59% of HIV-exposed infants received early infant diagnostic (EID) nucleic acid test by age 2 months, and only 54% of children living with HIV received ART. [12] In Nigeria, EID coverage has remained low; it has increased from 15% in 2015 to 27% in 2019. [7] EID programs require coordination and management of multiple separate health facilities/systems as well as significant logistical, financial, and human investments thus making it complex process with multiple challenges, requiring effective specimen transport, laboratory testing and results delivery, and potential loss of HIV-exposed infants at many points along the EID cascade. [13] Low demand for EID, inefficient procedures to follow up; infrastructure constraints especially power supply; stock out of EID commodities; EID backlogs, inconsistencies in sample pick up, loss of EID results long turnaround time of test results have been identified as some of the myriad of issues facing the EID programme in Nigeria. [8] [14]

To guide Quality PMTCT implementation at all levels of health care, Nigeria has transitioned through seven PMTCT guidelines from 2001 through to 2020 with Single-dose Nevirapine to mother and Nevirapine prophylaxis to the infant as the first ARV in preventing vertical transmission of HIV. [15] Currently, more efficacious cART with viral load determination is the standard of care for all HIV-positive pregnant women with ARV prophylaxis and EID for their exposed infants. [16]

The MTCT rate provides a measure of the effectiveness of the programme for preventing infant infections in pregnant women living with HIV. [17] The earliest PMTCT effectiveness studies [18] - [23] conducted in Nigeria reported MTCT rates of between 2.4% [24] and 22%. [25]

Transitioning to more efficacious cART for PMTCT between 2010 and 2012, several studies [26] - [42] in the country reported MTCT rates of between 0% [43] [44] and 9.7% [45] . Most recent reports from Sokoto, [46] FCT/Nasarawa state, [47] Delta, [48] Rivers [49] and Imo state [50] showed MTCT rates of 0.9%, 1%, 4%, 1.1%, and 3.7% respectively. A very large subregional report of EID of HEI by Dakum et al. [51] reported a MTCT rate of 5.2% at 12 weeks postpartum. Khamofu et al. reported declining MTCT rates with more efficacious cART in Nigeria. [52]

While most of these MTCT rates were determined at 6 - 8 weeks, in breastfeeding women in small sample sizes and short-duration reports, they no doubt were significant contributions to the PMTCT effort in the country. The current 2020 National HIV guideline [16] recommends that all HIV-exposed infants should have DNA PCR testing or NAT at birth, 6 - 8 weeks of age, 9 months and 8 - 12 weeks after complete cessation of breastfeeding. If the baby is not being breastfed, DNA PCR testing should be done at birth and 6 weeks.

The aim of this study was to report HIV infection in HIV-exposed infants from 5 states in the North East and North Central regions of Nigeria from 2009 to 2020.

2. Subjects, Materials and Methods

2.1. Study Design

This was a retrospective analysis of the results of Dried Blood Spot samples for DNA PCR testing of HIV-exposed infants.

2.2. Study Setting

Dried Blood Spot sample test results for HIV DNA from 5 states (Gombe, Yobe, Bauchi, Benue and Kaduna) in the Northern Region of the country from 2009 to 2020 were analyzed in the regional Polymerase Chain Reaction laboratory in the Federal Teaching Hospital, Gombe. DBS samples were from all levels of health care facilities including public and private, private profit and nonprofit and faith-based facilities in both rural and urban Nigeria. All HIV-exposed infants with positive DNA PCR were referred to the Paediatrics ART clinic.

This Molecular laboratory is one of the earliest DNA PCR Laboratories established in the country to support the Early Infant Diagnosis of HIV in the country. Cobas AmpliPrep (CAP)/Cobas TaqMan 96 (Roche Molecular Systems NJ) was used to detect HIV DNA. Molecular methods of DNA determination were used in accordance with the Manufacturer’s guide. The Quality Control and Assurance were ensured and maintained as recommended by the Federal Ministry of Health. The sample size was all consecutive Dried Blood spot samples that were analysed with their results from 2009 to 2020 in the Molecular laboratory in our health facility.

The following information was retrieved from the Laboratory forms and analyzed: Maternal ARV, ARV and Cotrimoxazole prophylaxis given to the infant, age at DBS Sample collection, sex, infant breast-feeding status and HIV DNA PCR test result.

Laboratory forms with incomplete information were excluded from analysis.

2.3. Ethical Clearance

Ethical clearance was received from the research and ethics committee of the Federal Teaching Hospital, Gombe (NHREC/25/10/2013).

2.4. Data Analysis

Data was analyzed using Epi info version 3.5.1. All data were analyzed with a statistical significance level set at p < 0.05. Frequencies, proportions, confidence intervals were computed. Results were summarized using tables and figures. Hypothesis testing was performed using Pearson Chi-Square as appropriate.

3. Results

Table 1 shows that 9,823 PCR DNA results were analysed during the study period. There was an over-all declining trend in the MTCT rate from 3.8% in 2009

Table 1. Yearly DBS sample collection 2009-2020 and HIV DNA PCR results.

X²: 84.047, p < 0.001.

to 0.8% in 2020 with blips in 2011 and 2016. Of the 9823 HIV DNA PCR results, 9568 (97.4%) had Negative DNA PCR while 255 (2.6%) were Positive.

Table 2 shows the distribution of maternal ARVs and Infant HIV DNA status; 6120 (62.3%) of HIV + mothers were receiving ART before pregnancy; 25.2 % (2475) started ART in pregnancy; 747 (7.6%) and 285 (2.9%) of HIV positive pregnant women did not receive and had unknown ARV status respectively. Regimen received by HIV-positive women was AZT + 3TC at 34 - 36 weeks gestation, AZT from 14 weeks gestation and single dose NVP in labour. Table 2 shows that 86 (11.5%) infants whose HIV-positive mothers received no ARVS were HIV DNA PCR positive; 98/6120 (1.6%) of mothers;32/2475 (1.3%); 10/98 (10.4%); 3/69 (4.5%) and 26/285 (9.1%) of infants whose HIV positive mothers had ART before pregnancy; ART during pregnancy; AZT mono-therapy; NVP Mono-therapy and those with unknown ARV status were HIV DNA PCR positive respectively (p = 0.001).

Infants who received ARV prophylaxis but whose mothers did not receive ART in pregnancy 747 (8.1%) had significantly more infection (p = 0.000) compared to infants who had received ARV with maternal ART (p = 0.971).

Table 2 shows that 7485 (76.2%) of HIV-exposed infants received NVP prophylaxis; 884 (9.1%) had no prophylaxis; 560 (5.6%) received AZT; 413 (4.2%) AZT/NVP and 481 (4.9%) of infants had unknown ARV (prophylaxis) status; 106/884 (12.0%) of HIV exposed infants who had no ARV prophylaxis; 10 (1.8%), 120/7485 (1.6%); 7/413 (1.7%) infants who received AZT mono-prophylaxis; NVP

Table 2. Maternal ARV status and infant HIV DNA PCR test results.

mono-prophylaxis and AZT/NVP dual prophylaxis had positive HIV DNA PCR result. (p = 0.000)

Dried Blood Spots samples were collected in 2514 (25.6%) of HIV exposed infants at <6 weeks of age; 41.5% (4077) at 6 - 8 weeks; 5.8% (570) at >8 - 12 weeks and 27.1% (2662) at >12 weeks postpartum. Table 3 shows that (58/2514) 2.3% 1.7% (69/4077); 3.3% (19/570) and 4.1% (109/2662) were positive for HIV DNA PCR at <6 weeks of age; 6 - 8 weeks; 8 - 12 weeks and >12 weeks respectively. There was an increasing likelihood of positive DNA PCR test results with a delay in DBS sampling and this was statistically significant (p = 0.000).

Table 3 also showed that 96.4% (9469/9823) infants were ever breastfed and 3.6% (354) had never breastfed. Daily cotrimoxazole was received by 85.9% (8438/9823) of the infants. About 2.6% (246/9469) of infants that were ever breastfed were positive for HIV DNA PCR and 2.5% (9/354) of infants that were never breastfed were positive for HIV DNA PCR (P = 0.348) (Table 3). In Table 3 more male infants than females had positive DNA PCR tests and was statistically significant p = 0.001. At the time of DBS sample collection infants of mothers who were not breastfeeding were DNA PCR positive compared to infants whose mothers were breastfeeding. However, this was not statistically significant (p = 0.295)

4. Discussion

This study showed that the HIV infection rate using the first DNA PCR at 6 - 8

Table 3. HIV-exposed infants’ profile and HIV DNA PCR result.

weeks in HIV-exposed infants was 2.6%. This rate is less than 5% expected in breastfeeding women on ART. [4] [5] Significantly there was a trend of declining MTCT rate over the years as the country transitioned to more efficacious combination ART. This similar trend was demonstrated earlier by Itiola [45] and Khamofu [52] in the country and Olana in Ethiopia. [53] These studies however had smaller number of mother-infant pairs and shorter study duration. Efficacious cART with viral load determination is the standard of care for all HIV-positive pregnant women with ARV prophylaxis and EID for their exposed infants. [10] [15] [16]

Increased DBS samples from 2016 in this study were as a result of additional logging to our laboratory from non-functional PCR laboratories in some parts of in the country.

In this study, forty-two percent of the first DBS samples were obtained within the 6 - 8 weeks period as recommended by the National guideline; [10] [15] [16] a third of DBS were taken after this period with increasing possibility of positive DNA test result. (p = 0.01). This finding is similar to the report by Dakum et al. [51] ; however, the proportion of DBS sample obtained at 6 - 8 weeks in our study is twice as high as reported by Dakum et al. [51] and Itiola et al. [45] in the country. Reports on fairly large number of HIV-exposed infants in the country by Anoje et al., [28] Olerigbe et al., [41] Ibobo et al., [48] did not report 6 - 8 weeks age of DBS sample collection. Higher DBS collection rates at 6 - 8 weeks of 67.3%, 50%, and 79% have been reported in Ethiopia, [53] Malawi, [54] and Kenya, [55] respectively. HIV DNA PCR testing through DBS collection at 6 - 8 weeks has a very high sensitivity and is considered programmatically more efficient and therefore reported. [10] [15] [16] [56]

Overall, more than three-quarters of HIV-positive women in our report had received ART and had lower MTCT rate compared to women who had less efficacious ARV consisting of two or less ARVS. This is in agreement with the findings of Khamofu et al. [52] and Itiola et al. [45] with however much smaller sample sizes and shorter study duration. Highly Active Antiretroviral therapy or combination ART with at least three antiretroviral have more durable and sustained maternal viral suppression with reduced risk of MTCT of HIV. [23] [26] High Maternal viral load in Pregnancy is a major risk factor for MTCT. [10] [15] [16]

In this study, 7.6% of HIV-positive pregnant women did not receive ARVs and therefore had higher MTCT rates. This is similar to 7% reported by Dakum et al. [51] but lower than the 13% and 38.5% reported by Itiola et al. [45] and Anoje et al. [28] respectively. A much lower proportion of HIV-positive pregnant women did not receive ARVs in the report of these workers. [41] [48] While this study showed 2.9% of HIV-positive mothers with missing data on ARVs, these workers [49] [51] reported 17.4% and 12.2% respectively. Similarly, 9.1% of HIV-exposed infants did not receive ARV prophylaxis and 4.9% had missing data on ARVs. Infant HIV infection was highest in the former category in our study. A much higher proportion of 17.1% [45] and 38.2% [28] of HEI did not receive ARV prophylaxis. This infant status was not reported by Dakum et al. [51] Infant ARV prophylaxis is an indicator of the quality of PMTCT service delivery. [10] [15] [16] Increased odds of infant HIV infection with lack of Maternal ARV and infant HIV prophylaxis have also been reported. [53] [54] [55]

Missing data, unknown status and non-administration of ARVs in PMTCT programme remain significant challenges in the country traceable to gaps in training, human resource constraints, monitoring and evaluation and lack of electronic medical records. [7] [8] [12] [14]

At the time of DBS sample collection, 87% of HEI were breastfeeding and overall, 96.4% of these infants reported ever breastfed. In this study, there is a significant relationship between the duration of breastfeeding and positive DNA PCR test result with prolonged Breastfeeding increasing the risk. This relationship between prolonged breastfeeding and infant HIV infection has also been reported by workers in Nigeria [41] [45] [48] [51] and in Ethiopia [53] and Kenya. [55] . The risk of postnatal transmission through breastfeeding is associated with clinical, immunological and virological maternal factors and infant feeding patterns. [57] Maternal seroconversion during breastfeeding, low maternal CD4 cell count, increased maternal RNA viral load in plasma and breast milk are strongly associated with increased risk of transmission. Breast pathologies such as clinical and subclinical mastitis, nipple bleeding, and abscesses, fissures or lesions are also associated with a higher risk of transmission through breastfeeding. [57] Mother-to-child transmission rates of HIV through breastfeeding is 13% at six weeks rising to 23% at the end of breastfeeding. [7] Breastfeeding remains and will be the topmost item on the agenda of child survival globally and especially in low- and medium-income countries. [1] [2] [16]

5. Limitations

There are several limitations in this study; this is the first HIV DNA PCR results analyzed and therefore we are unable to determine subsequent and final HIV infant outcomes. Our study did not report other maternal and infant characteristics like CD4 + cell count, viral load, WHO clinical stage, follow-up infant status, or cessation of breastfeeding that would affect final infant outcomes. As a retrospective study, information may have been incomplete and the MTCT rate therefore and estimation and not the actual. In spite of its limitations, the large sample size, the long duration of review and evidence of PMTCT effectiveness through different ART regime remain the strength of this study.

6. Conclusions

Mother-to-child transmission of HIV infection rate has declined with the use of efficacious combination ARV therapy in five states of Northern Nigeria.

Prolonged breastfeeding is associated with the risk of transmission of HIV especially in the absence of maternal and infant ARV.

7. Recommendation

PMTCT requires strengthening, especially the provision of maternal and infant ARV in northern Nigeria and the country in general.

Author Contribution

Elon Warnow Isaac: Conceived of the study and study design, developed the first manuscript draft and critically reviewed all drafts of the manuscript.

Dr Iliya Jalo, Dr. Abubakar Joshua Difa, and Ms. Oyeniyi Christianah Oluwaseun: Conducted quantitative data analysis and reviewed all drafts of the manuscript.

Dr Mohammed Manga and Mr. Muhammad Danlami Hassan: Reviewed and commented on the data.

Acknowledgments

We wish to acknowledge Hajiya Fatima Y Aliyu, Hajiya Zainab Dan-Malam and Hafsat Sabo of the Data unit of Paediatrics department for extracting the data.

Funding

There was no funding received for this study.

Conflicts of Interest

The authors declare no conflicts of interest regarding the publication of this paper.

References

[1]	World Health Organization (2018) Mother-to-Child Transmission of HIV. https://apps.who.int/iris/bitstream/handle/10665/259517/9789241513272-eng.pdf
[2]	United Nations Children’s Fund (2020) Monitoring the Situation of Children and Women. Elimination of Mother-to-Child Transmission. https://data.unicef.org/topic/hivaids/emtct/
[3]	Joint United Nation Programme on HIV/AIDS (2021) Miles to Go—Closing Gaps, Breaking Barriers, Righting Injustices. https://www.unaids.org/en/resources/documents/2018/global-aids-update
[4]	United Nations Children’s Fund, Joint United Nation programme on HIV/AIDS and World Health Organization (2021) Key Considerations for Programming and Prioritization. Going the “Last Mile” to EMTCT: A Road Map for Ending the HIV Epidemic in Children. http://www.childrenandaids.org/Last-Mile-to-EMTCT
[5]	United Nations Children’s Fund and Joint United Nation Programme on HIV/AIDS (2016) Sustainable Development Knowledge Platform: Sustainable Development Goals. https://sdgs.un.org/goals
[6]	Global Health Observatory (GHO) Data (2019) Prevention of Mother-to-Child Transmission. Situation and Trends. https://www.who.int/data/gho/data/themes/topics/indicator-groups/indicator-group-details/GHO/prevention-of-mother-to-child-transmission
[7]	Joint United Nation Programme on HIV/AIDS (2017) Start Free, Stay Free, AIDS Free: 2017 Progress Report. https://www.unaids.org/sites/default/files/media_asset/JC2923_SFSFAF_2017progressreport_en.pdf
[8]	(2021) The Global Fund to Fight AIDS, Tuberculosis & Malaria. https://www.theglobalfund.org/media/10170/core_pmtctearlyinfantdiagnosis_review_en.pdf
[9]	World Health Organization (2016) Consolidated Guidelines on the Use of Antiretroviral Drugs for Treating and Preventing HIV Infection: Recommendations for a Public Health Approach. https://apps.who.int/iris/handle/10665/208825
[10]	Federal Ministry of Health (2010) Guidelines for HIV Prevention Treatment and Care Nigeria National HIV/STIs Prevention and Control Programme, Nigeria.
[11]	Violari, A., Cotton, M.F., Gibb, D.M., et al. (2008) Early Antiretroviral Therapy and Mortality among HIV-Infected Infants. The New England Journal of Medicine, 359, 2233-2244. https://doi.org/10.1056/NEJMoa0800971
[12]	Joint United Nation Programme on HIV/AIDS (2019) Power to the People. Geneva. https://www.unaids.org/sites/default/files/media_asset/power-to-thepeople_en.pdf
[13]	Mofenson, L.M., Cohn, J. and Sacks, E. (2020) Challenges in the Early Infant HIV Diagnosis and Treatment Cascade. JAIDS Journal of Acquired Immune Deficiency Syndromes, 84, S1-S4. https://doi.org/10.1097/QAI.0000000000002366
[14]	Inalegwu, A., Phillips, S., Datir, R., Chime, C., Ozumba, P., Peters, S., et al. (2016) Active Tracking of Rejected Dried Blood Samples in a Large Program in Nigeria. World Journal of Virology, 5, 73-81. http://www.wjgnet.com/2220-3249/full/v5/i2/73.htm https://doi.org/10.5501/wjv.v5.i2.73
[15]	Federal Ministry of Health (2016) National Guidelines for Prevention of Mother to Child Transmission of HIV in Nigeria. National HIV/STIs Prevention and Control Programme, Federal Ministry of Health.
[16]	Federal Ministry of Health (2020) Guidelines for HIV Prevention Treatment and Care National HIV/STIs Prevention and Control Programme, Nigeria, Federal Ministry Health.
[17]	World Health Organization (2017) HIV Global Guidance on Criteria and Processes for Validation: Elimination of Mother-to-Child Transmission of HIV and Syphilis, 2nd Edition. https://apps.who.int/iris/handle/10665/259517
[18]	Adegoke, O.D., Basir, Z., Jumare, J., Sani, S., Enzama, R., Peters, S., et al. (2009) Outcome of Early Infant Diagnosis in Exposed Infants in Northern Nigeria. JAIDS Journal of Acquired Immune Deficiency Syndromes, 51. https://doi.org/10.1097/01.qai.0000351200.37648.bc
[19]	Ugochukwu, E.F. and Kalu, S.O. (2009) Early Infant Diagnosis of HIV Infection in Southeastern Nigeria: Prevalence of HIV Infection among HIV-Exposed Babies. West African Journal of Medicine, 29, 3-7. https://doi.org/10.4314/wajm.v29i1.55945
[20]	Okeudo, C., Ezem, B. and Ojiyi, E. (2012) Mother-To-Child Transmission Rate of HIV at Orlu, South-Eastern Nigeria. The Internet Journal of Gynecology and Obstetrics, 16.
[21]	Imade, P.E., Uwakwe, N.O., Omoregie, R. and Eghafona, N.O. (2010) Effect of Prevention of the Mother to Child Transmission Program on the Prevalence of Postnatal HIV Infection in Benin City, Nigeria. Fooyin Journal of Health Sciences, 2, 58-61. https://doi.org/10.1016/S1877-8607(10)60016-1
[22]	Afe, A.J., Adewumi, N., Emokpae, A., Fagorala, T., et al. (2011) Outcome of PMTCT Services and Factors Affecting Vertical Transmission of HIV Infection in Lagos, Nigeria. HIV & AIDS Review, 10, 14-18. https://doi.org/10.1016/j.hivar.2011.02.001
[23]	Chama, C., Gashau, W. and Oguche, S. (2007) The Value of Highly Active Antiretroviral Therapy in the Prevention of Mother-to-Child Transmission of HIV. Journal of Obstetrics and Gynaecology, 27, 134-137. https://doi.org/10.1080/01443610601113854
[24]	Sadoh, W.E., Omoigberale, A.I., Esene, H.A. and Onakewhor, J.U.E. (2008) Mother-to-Child Transmission of HIV at the University of Benin Teaching Hospital, Benin City, Nigeria. Sahel Medical Journal, 11, 118-124. https://doi.org/10.4314/smj2.v11i4.12984
[25]	Audu, R.A., Salu, O.B., Musa, A.Z., et al. (2006) Estimation of the Rate of Mother-to-Child Transmission in Nigeria. African Journal of Medicine and Medical Sciences, 35, 121-124.
[26]	Chama, C.M., Bello, M., Ajayi, B.A., Zarma, S. and Gashau, W. (2010) The Use of Highly Active Antiretroviral Therapy for the Prevention of Mother-to-Child Transmission of the Human Immunodeficiency Virus in Nigeria. Journal of Obstetrics and Gynaecology, 30, 362-366. https://doi.org/10.3109/01443611003672104
[27]	Ikechebelu, J.I., Ugboaja, J.O., Kalu, S.O. and Ugochukwu, E.F. (2011) The Outcome of Prevention of Mother to Child Transmission (PMTCT) of HIV Infection Programme in Nnewi, Southeast Nigeria. Nigerian Journal of Medicine, 20, 421-425.
[28]	Anoje, C., Aiyenigba, B., Suzuki, C., Badru, T., Akpoigbe, K., Odo, M., et al. (2012) Reducing Mother-to-Child Transmission of HIV: Findings from an Early Infant Diagnosis Program in South-South Region of Nigeria. BMC Public Health, 12, Article No. 184. https://doi.org/10.1186/1471-2458-12-184
[29]	Esene, H. and Omoigberale, A.I. (2012) Prevalence of HIV among Exposed Infants in University of Benin Teaching Hospital, Benin City, Edo State, Nigeria. Journal of Biomedical Science, 11, 105-115.
[30]	Ben, O. and Yusuf, T. (2014) PCR Pattern of HIV-Exposed Infants in a Tertiary Hospital. The Pan African Medical Journal, 18, Article 345.
[31]	Sagay, A.S., Ebonyi, A.O., Meloni, S.T., Musa, J., Oguche, S., Ekwempu, C.C., et al. (2015) Mother-to-Child Transmission Outcomes of HIV-Exposed Infants Followed up in Jos North-Central Nigeria. Current HIV Research, 13, 193-200. https://doi.org/10.2174/1570162X1303150506182534
[32]	Agboghoroma, C.O., Audu, L.I. and Iregbu, K.C. (2015) Effectiveness of Prevention of Mother-to-Child Transmission of HIV Program in Abuja. Journal of HIV & Human Reproduction, 3, 7-13. http://www.jhhr.org/temp/JHIVHumReprod317-5201927_142659
[33]	Oyesakin, A.B., Akinsuli, A., Oniyangi, O., Audu, L. and Ogunfowokan, O. (2016) PMTCT Programme Reduced Vertical Transmission of HIV in Abuja, Nigeria. Nigerian Journal of Paediatrics, 43, 166-199. https://doi.org/10.4314/njp.v43i3.2
[34]	Kalu, S., Reynolds, F., Petra, G., Ikechebelu, J., Dada, M., Oluboyo, B., et al. (2014) Infant Feeding Choices Practiced among HIV-Positive Mothers attending a Prevention of Mother-to-Child Transmission (PMTCT) of HIV Program in Nnewi, Nigeria. Journal of AIDS & Clinical Research, 5, Article ID: 1000300.
[35]	Mukhtar-Yola, M., Otuneye, A.T., Mairami, A.B., Wey, Y., Nwatah, V. and Audu, L.I. (2018) Audit of Prevention of Mother-to-Child Transmission Programme Interventions in HIV-Exposed Children at National Hospital, Abuja, Nigeria. Nigerian Postgraduate Medical Journal, 25, 27-31. https://doi.org/10.4103/npmj.npmj_151_17
[36]	Chukwuemeka, I.K., Fatima, M.I., Ovavi, Z.K. and Olukayode, O. (2014) The Impact of a HIV Prevention of Mother to Child Transmission Program in a Nigerian Early Infant Diagnosis Centre. Nigerian Medical Journal, 55, 204-208. https://doi.org/10.4103/0300-1652.132039
[37]	Abdulmumini, I., Uchena, I.N., Adibe, M.O. and Ukwe, C.V. (2016) Evaluation of Prevention of Mother-to-Child Transmission (PMTCT) of HIV in a Tertiary Health Institution in South-Eastern Nigeria. Journal of AIDS and HIV Research, 8, 114-120. https://doi.org/10.5897/JAHR2016.0375
[38]	Oluwayemi, I.O., Olatunya, S.O. and Ogundare, E.O. (2015) PCR Results and PMTCT Treatment Outcomes among HIV-Exposed Infants in a Tertiary Hospital in Nigeria, 2010-2014. International Journal of Maternal and Child Health and AIDS, 3, 168-173. https://doi.org/10.21106/ijma.49
[39]	Fasakin, K.A., Omisakin, C.T., Adebara, I.O., Ajetunmobi, W.A., Adeniyi, A.A., Esan, A.J., et al. (2018) Assessment of PMTCT Success Rates Based on Antiretroviral Interventions and Feeding Options: A Prospective Cohort Study. International Journal of Maternal and Child Health and AIDS, 7, 226-234. https://doi.org/10.21106/ijma.266
[40]	Pharr, J.R., Obiefune, M.C., Ezeanolue, C.O., Osuji, A., Ogidi, A.G., Gbadamosi, S., et al. (2016) Linkage to Care, Early Infant Diagnosis, and Perinatal Transmission among Infants Born to HIV-Infected Nigerian Mothers: Evidence From the Healthy Beginning Initiative. JAIDS Journal of Acquired Immune Deficiency Syndromes, 72, S154-S160. https://doi.org/10.1097/QAI.0000000000001051
[41]	Oleribe, O.O., Enenche, E., Udofia, D., Ekom, E., Osita-Oleribe, P.I., Kim, J.U., et al. (2018) Assessment of the Effectiveness of PMTCT Program in Eight Service Delivery Points in North Central Nigeria. HIV/AIDS—Research and Palliative Care, 10, 253-259. https://doi.org/10.2147/HIV.S157685
[42]	Afolabi, A.Y., Bakarey, A.S., Kolawole, O.E. and Kola, O.J. (2018) Investigation of Mother-to-Child Transmission of HIV in Pregnancy and among HIV-Exposed Infants Accessing Care at a PMTCT Clinic in Southwest Nigeria. Journal of Immunoassay and Immunochemistry, 39, 403-415. https://doi.org/10.1080/15321819.2018.1494607
[43]	Iloh, K.K., Iloh, O.N., Ikefuna, A.N., Ibeziako, N.S., Ubesie, A.C. and Emodi, I.J. (2015) Determinants of Mother-to-Child Transmission of HIV Despite PMTCT Interventions in Enugu, Nigeria. South African Journal of Child Health, 9, 49-52.
[44]	Okafor, I., Ugwu, E., Obi, S. and Odugu, B. (2014) Virtual Elimination of Mother-to-Child Transmission of Human Immunodeficiency Virus in Mothers on Highly Active Antiretroviral Therapy in Enugu, South-Eastern Nigeria. Annals of Medical and Health Science Research, 4, 615-618.
[45]	Itiola, A.J., Goga, A.E. and Ramokolo, V. (2019) Trends and Predictors of Mother-to-Child Transmission of HIV in an Era of Protocol Changes: Findings from Two Large Health Facilities in North East Nigeria. PLOS ONE, 14, e0224670. https://doi.org/10.1371/journal.pone.0224670
[46]	Mairo, H., Panti, A.A., Tunau, K.A., Nasir, S., Burodo, A.T., Adamu, N.A., et al. (2018) Determinants of Mother to Child Transmission of HIV among HIV Exposed Infants Managed in Usmanu Danfodiyo University Teaching Hospital, Sokoto, Nigeria. International Journal of Reproduction, Contraception, Obstetrics and Gynecology, 7, 4413-4417. https://doi.org/10.18203/2320-1770.ijrcog20184482
[47]	Anaba, U.C., Sam-Agudu, N.A., Ramadhani, H.O., Torbunde, N., Abimiku, A., Dakum, P., et al. (2019) Missed Opportunities for Early Infant Diagnosis of HIV in Rural North-Central Nigeria: A Cascade Analysis from the INSPIRE MoMent Study. PLOS ONE, 14, e0220616. https://doi.org/10.1371/journal.pone.0220616
[48]	Ibobo, J.A., Chime, H. and Nwose, E.U. (2018) Prevention of Mother-to-Child Transmission of HIV in Delta State of Nigeria: Evaluation of the Early Infant Diagnosis Program. Journal of Health Science Research, 3, 16-23. https://doi.org/10.18311/jhsr/2018/20020
[49]	Paul, N.I. and Ugwu, R.O. (2019) Outcome of Prevention of Mother to Child Transmission (PMTCT) of HIV Services at the University of Port Harcourt Teaching Hospital (UPTH), Port Harcourt, Nigeria. Asian Journal of Medicine and Health, 17, 1-11. https://doi.org/10.9734/ajmah/2019/v17i230159
[50]	Ejikunle, S.D., Mbachu, I.I., Okeudo, C., Dike, E. and Ejikem, E. (2019) Incident HIV Infection and Perinatal Transmission Rates among HIV Negative Pregnant Women Who Retested in Labor in a Tertiary Health Centre, South East Nigeria. Nigerian Journal of Clinical Practice, 22, 1341-1348. https://doi.org/10.4103/njcp.njcp_130_17
[51]	Dakum, P., Tola, M., Iboro, N., Okolo, C.A., Anuforom, O., Chime, C., et al. (2019) Correlates and Determinants of Early Infant Diagnosis Outcomes in North-Central Nigeria. AIDS Research and Therapy, 16, Article No. 27. https://doi.org/10.1186/s12981-019-0245-z
[52]	Khamofu, H., Oladele, E.A., Ralph-Opara, U., Badru, T., Adedokun, O., Saleh, M., et al. (2015) Decline in Positivity Rates among HIV-Exposed Infants with Changes in the Prevention of Mother-to-Child Transmission Antiretroviral Regimens in Nigeria: Evidence from 7 Years of Field Implementation. Journal of HIV and Human Reproduction, 3, 34-40. https://doi.org/10.4103/2321-9157.186351
[53]	Olana, T., Bacha, T., Worku, W. and Tedesse, B.T. (2016) Early Infant Diagnosis of HIV Infection Using DNA-PCR at a Referral Center: An 8 Years Retrospective Analysis. AIDS Research and Therapy, 13, Article No. 29. https://doi.org/10.1186/s12981-016-0112-0
[54]	Phiri, N.A., Lee, H.Y., Chilenga, L., Mtika, C., Sinyiza, F., Musopole, O., et al. (2017) Early Infant Diagnosis and Outcomes in HIV-Exposed Infants at a Central and a District Hospital, Northern Malawi. Public Health Action, 7, 83-89. https://doi.org/10.5588/pha.16.0119
[55]	Gaitho, D., Kinoti, F., Mwaniki, L., Kemunot, D., Ogoti, V., Njigua, C., et al. (2021) Factors Associated with the Timely Uptake of Initial HIV Virologic Test among HIV-Exposed Infants Attending Clinics within a Faith-Based HIV Program in Kenya; a Cross-Sectional Study. BMC Public Health, 21, Article No. 569. https://doi.org/10.1186/s12889-021-10587-1
[56]	World Health Organization (2021) Early Detection of HIV Infection in Infants and Children. https://www.who.int/hiv/paediatric/EarlydiagnostictestingforHIVVer_Final_May07.pdf
[57]	World Health Organization (2007) HIV Transmission through Breastfeeding: A Review of Available Evidence: 2007 Update. http://apps.who.int/iris/bitstream/handle/10665/43879/9789241596596_eng.pdf