HIV Transmission After Birth: Mechanism, Complications, and Prevention

Introduction:

Acquired immunodeficiency syndrome (AIDS) is one of the fatal medical conditions. This is caused by the infection of the human immunodeficiency virus (HIV). HIV infection disrupts normal defense and is associated with a spectrum of fatal conditions. mechanism of the body Around 38.5 million people worldwide are suffering from AIDS. Among these people, around 1.3 million women living with HIV become pregnant each year. One of the main complications associated with pregnancy in HIV is the transmission of infection to the newborn. 95 percent of cases of infant HIV are associated with maternal transmission. This is associated with a significant number of infant mortality among newborns.

What Is HIV?

Human immunodeficiency viruses (HIV) are types of retrovirus. They enter the human body as single-stranded RNA (ribonucleic acid) viruses. After which they entered the target cell and changed to double-stranded DNA (deoxyribonucleic acid) with the help of the reverse transcriptase enzyme. HIV virus is of two types. HIV 1 virus is predominantly seen all over the world. This type of virus is highly virulent and infectious. HIV 2 is less virulent and mainly seen in West African counties.

• Transmission of HIV:

The main mood of transmission of HIV is:

1. Through unprotected sexual contact. The virus can transmit through vaginal fluids, semen, and secretions of the genital organs.

2. During a blood transfusion, if the donor receives the blood of the affected person.

3. Needle prick is the most common cause of cross-contamination using the same needle that is off the infected person or sharing needles (occasionally done by drug addicts) may cause transmission of infection.

4. It can transmit the child from the mother during pregnancy via placental circulation. HIV can infect trophoblast and placental macrophages. Transmission may also occur during delivery due to membrane rupture, blood contamination, or breastfeeding. This mood of transmission is also called vertical transmission. Also, oral exposure to maternal genital secretion may be associated with vertical transmission.

5. This infection is not transmitted through touch, kissing, or saliva.

• Pathophysiology of HIV:

The envelope or the outermost layer of the HIV viruses fused with the cell membranes of macrophages and CD4+T lymphocytes by adsorptions of glycoproteins. They can also infect dendritic cells (antigen-presenting cells) transmitted through the sexual route. After this, ribonucleic acid and various enzymes are injected into the cells. Here synthesis of complementary deoxyribonucleic acid (DNA). These infected CD4+ T cells are destroyed by CD8+ T cells. As a result, the number of CD4+ cells dropped dramatically. In the chronic phase, the drop in CD4+ t lymphocyte cells causes the secondary infection. Infection also affects cells like the nervous system's macrophages, monocytes, and microglia cells.

What Are the Complications?

HIV in pregnancy is associated with preterm delivery, stillbirth, and abortions are potential medical complications. Fetal transmission can lead to several complications:

1. Growth reradiation and low birth weight can be seen.

2. Cardiac disorders of the newborn, such as septal defects, can be seen.

3. Smaller head circumference of the baby due to cortical atrophy and calcification of basal ganglion.

4. Alteration of brain function and neurological dysfunctions.

5. Pneumocystis carinii pneumonia is one of the most common complications. The fungi Pneumocystis jiroveci causes this.

What Is the Delivery Protocol?

The child's delivery status depends upon the mother's anti-viral therapy. The following protocols should be maintained during delivery:

1. If the mother is under anti-retroviral therapy and the viral load is less than 1000 copies per milliliter, normal vaginal delivery can be performed under proper sterilization and asepsis conditions.

2. For women whose anti-viral therapy status is unknown and whose viral load is more than 1000 copies per milliliter, cesarean delivery can be performed at the 38th week of pregnancy. In such cases, intravenous administration of zidovudine (ZDV), three hours before the surgery (dose - 2 milligrams per kilogram), followed by continuous infusion over 2 hours (dose - 1 milligram per kilogram per hour) during the procedure is administered.

3. In case of spontaneous fetal membrane rupture, delivery should be done within 24 hours.

4. Post-delivery breastfeeding should not be done.

What Is the Treatment Protocol For the Mother?

Treatment of the infected mother is necessary to reduce the chance of vertical transmission. For this purpose, HIV tests are done at various stages of pregnancy. The advised treatment regimen is as follows:

1. Ideal anti-retroviral therapy is the administration of Zidovudine (300 milligrams twice daily) and Lamivudine (150 milligrams twice daily). Together with these drugs Efavirenz (200 milligrams twice daily) or Nevirapine (600 milligrams once daily) is also advised. Another protocol of medication includes Tenofavir (300 milligrams once daily) along with Lamivudine (300 milligrams once daily or 150 milligrams twice daily if Nevirapine is used) and Efavirenz (600 milligrams once daily) or Nevirapine (200 milligrams twice daily) is prescribed.

2. For pre-exposure prophylaxis of high-risk individuals, A combination of tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) is prescribed daily for oral consumption.

What Is the Treatment Protocol for Newborns?

As discussed, the treatment protocol for the child starts with the mother's treatment. For a child whose mother is receiving anti-retroviral therapy and the baby is born after the 37th week of pregnancy, the following treatment protocol should be maintained:

1. Zidovudine (AZT) is prescribed to a child whose weight is more than 2500 grams. The dose reign is 15 milligrams per dose twice daily for four to six weeks. If the child's weight is less than 2500 grams, 10 milligrams of Zidovudine (AZT) are given twice daily for four to six weeks.

2. Nevirapine (NVP) can be prescribed alternatively. For children weighing more than 2500 grams, 15 milligrams can be given once daily for four to six weeks. If the child weighs between 2000 to 2500 grams, 10 grams once daily. If the weight is below 2000 grams, the Nevirapine (NVP) dose regimen is 2 milligrams per kilogram of body weight.

Both drugs can be extended up to 12 weeks. But in certain cases, a shorter regimen of two weeks of prophylaxis treatment is advised. In this scenario, the mother must have completed more than four weeks of antiretroviral therapy, and the viral load should be less than 50 copies per milliliter in at least two tests two weeks apart. There is also a second category of children who are considered high-risk groups. In such cases, the mother has received neither anti-retroviral therapy nor intrapartum anti-retroviral drugs. In such cases, the viral load is not suppressed significantly. In such cases, a three-drug regimen is prescribed. Three drugs are Zidovudine (AZT), Lamivudine, and either Nevirapine (NVP) or Raltegravir (RAL). This is also known as presumptive HIV Therapy.

Conclusion:

Vertical transmission is a major risk factor during pregnancy. HIV infection transmitted to the child via the mother may cause severe complications. Assessment of HIV infection of the mother at various stages of pregnancy and proper anti-viral therapy helps reduce the chance of exposure. Also, proper medication and delivery technique is helpful in minimizing HIV complications.