CHAPTER ONE

INTRODUCTION

Acquired immuno-deficiency syndrome (AIDS) is a disease condition caused by infection of the human body by a

retrovirus called the human immunodeficiency virus (HIV) 1. On entry into the body, the virus invades the Cluster differentiation 4 (CD4) cells in which it replicates. Its

successful multiplication leads to the destruction of the CD4

cells. Thus, the CD4  cells count reduces as the viral load

increases.

The CD4 cells are responsible for the protection of the human

body against numerous pathogenic organisms with which it comes into contact in day to day living. Depletion of the CD4

cells leads to immune deficiency state and an increased likelihood of the body being invaded by opportunistic organisms. These organisms, which are ordinarily harmless to the human body, then become pathogenic and cause what is

known as opportunistic infections 2. It is the opportunistic infections that persistently reduce the quality of life of the

1

individual and eventually result in death if treatment is not promptly and adequately provided. Highly Active Anti-retroviral Therapy (HAART), when promptly and adequately

provided and taken, reduces HIV morbidity and mortality 3, 4.

Magnitude of the Problem of HIV/AIDS

The HIV and AIDS pandemic is one of the most serious health crises in the world today. By the end of 2008, AIDS and AIDS-related illnesses had killed more than 25 million people (2 million in 2008 alone including 280,000 children under 15 years) and an estimated 35.8million people were living with HIV, out of which 15.7 and 2.1million were women and

children under 15 years respectively5. Sub-Saharan Africa has continued to bear the greatest burden of the HIV and AIDS epidemic, with approximately 67% of the total number of people living with HIV, 68% of the new infections and 72% of AIDS-related deaths in 2008. Over the decades, the epidemic, once dominated by infected males has become progressively feminized and in sub-Saharan Africa approximately 60% of

adults living with the HIV are women6,7,8.

2

Over 90% of infection in children is acquired through mother-to-child transmission (MTCT) and as more women contract the

virus, the number of children infected also increases9. Estimate of the Global HIV pandemic demonstrated that in sub-Saharan Africa, more than 1200 children become infected

with HIV each day5. In 2008 alone an estimated 2.1 million children were living with HIV and up to 430,000 were newly infected worldwide, with sub-Saharan Africa accounting for

about 90% of both of these figures5.

Nigeria, with a population of 140 million10, is the most populous country in Africa and was ranked 2nd worst affected

by HIV/AIDS in the world in 2008 after South Africa5. Since the first case of HIV/AIDS in Nigeria was reported in 1986

involving a 13 year old girl who died of the disease11, there has been progressive increase in the total number of people living with HIV/AIDS (PLWHA). The national prevalence rose from 1.8% in 1991 to 5.8% in 2001 but declined to 5% in 2003 and 4.4% in 2005 before rising again to 4.6% in 2008

with prevalence in Anambra State determined to be 5.6%12.

3

The HIV prevalence rate is higher in the urban (5.4%) than rural areas (3.4%). Among young persons, the highest

prevalence rate of 5.6% is in the age group 25 to 29 years13. The average number of adults living with HIV was 3,500,000 in 2005 at a time when number of women (15-49 years old) living with HIV was 1,900,000, giving a female: male ratio of 1.2:1. Heterosexual transmission accounts for nearly 80% to

95% of all infections14. About 10% of HIV infections are transmitted by MTCT, while another 10% is transmitted by the use of unsterilized needles and surgical implements, infected

blood and blood products15.

Mother-to-Child Transmission of HIV

Over 90% of HIV infections in children less than 15 years are due to MTCT. In the absence of interventions, between 15% and 45% of infants born to HIV-infected mothers acquire the infection during pregnancy, delivery or through breast-

feeding16. The burden of MTCT of HIV is higher in sub-Saharan Africa than the rest of the world, because of higher

4

levels of hetero-sexual transmission, high female to male ratio, high total fertility rate (TFR) and high rate of breast-

feeding17,18. Transmission of HIV in children has become a critical health problem undermining the positive impact of

child survival strategies in the African continent19,20.

Estimated magnitude of MTCT in Nigeria

Population

140 million

Birth rate per annum

42/ 1000

Birth per annum

5,900,000

HIV prevalence in ANC women

4.4%

Total number of  infants born

to

HIV infected women exposed to the

260,000

risk of MTCT assuming no multiple

pregnancy

Number of HIV positive infants per

65,000 to 117,500

annum

Source: FMOH. National Guidelines on Prevention of Mother-

to-Child Transmission of HIV, July 2007.

5

Risk Factors for MTCT of HIV

Factors associated with increased risk of MTCT of HIV

Factors strongly associated with MTCT of HIV include viral characteristics and high viral load; maternal advanced disease, immune deficiency and HIV infection acquired during

pregnancy or breastfeeding21,22, obstetric practices like vaginal

delivery23, rupture of membranes for more than 4 hours

before delivery24; prematurity of the infant; and feeding factors like prolonged breastfeeding, mixed feeding and breast diseases like abscess, mastitis and cracked nipples during

breastfeeding25.

Other factors associated with MTCT of HIV but with limited evidence include viral resistance; maternal vitamin A deficiency, anaemia, Chorioamnionitis, sexually transmitted diseases, frequent unprotected sex, multiple sexual partners, smoking and intravenous drug abuse; obstetric practices like invasive or traumatic procedures, instrumental deliveries, amniocentesis, episiotomy, external cephalic version and intra-partum haemorrhage; and foetal or infant lesions of the skin or mucous membranes and genetic factors.

6

Prevention of Mother-to-Child Transmission of HIV

One of the goals of the June 2001 Declaration of Commitment of the United Nations General Assembly Special Session on

HIV/AIDS (UNGASS)26 is to reduce the proportion of infants infected with HIV by 20% by 2005 and 50% by 2010. The Nigeria national goal for PMTCT as contained in the 2003 AIDS Policy is to reduce the transmission of the HIV through MTCT by 50% by the year 2010 and to increase access to quality voluntary confidential counseling and testing services by 50% by the same year. To achieve this goal, a comprehensive strategy to prevent HIV infection among infants and young children has been developed, which promotes implementation in an integrated manner within the health care delivery system.

The NAUTH PMTCT programme started in 2003 as a national programme implemented by the Federal Government of Nigeria with NAUTH as one of the pilot sites. The NAUTH programme was taken over by the Institute of Human Virology Nigeria (IHVN) in 2005. NAUTH has 7 satellite sites,

7

including 3 private hospitals, for the PMTCT programme which is implemented according to the National Guidelines on

Prevention of Mother-to-Child Transmission of HIV15.

The PMTCT interventions consist of four strategic approaches which include:

1.      Primary prevention of HIV infection in women of reproductive age group and their partners

This involves provision of early diagnosis and treatment of STIs, making HIV testing and counseling widely available and provision of suitable counseling for women who are HIV negative.