FAQs: Routes of Transmission

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How is HIV transmitted?

There are four routes of transmission for HIV: 1) unprotected sex with an infected person; 2) infected mother to child, either during pregnancy, delivery or through breastfeeding; 3) through contaminated blood and blood products (including organ and tissue transplants); and 4) sharing of unsterilized infected needles, syringes and other medical equipment like dentists’ instruments.

What are the conditions for transmission of HIV through unprotected sex?

One person must be infected with HIV to pass it to another person. Unprotected penetrative vaginal intercourse is the most common route of HIV transmission, while anal sex, whether male-to-male or male-to-female, poses a higher risk for transmission. It is rare but possible to acquire HIV through oral sex, particularly if the person has ulcers or sores in their mouth. Kissing and other non-penetrative sexual activities do not pose a risk of HIV transmission.

Are there times when people with HIV are more able to transmit HIV?

A person if more infectious when there is a greater viral load or concentration of the HIV virus in their blood. There is a greater viral load in the body when a person first contracts HIV, before the body has had a chance to build a defence/create antibodies to the virus, and later during the progression of the virus, when the immune system is weakened. A person with a sexually transmitted infection (STI) is also more likely to transmit HIV when they participate in unprotected sex, due to the higher concentration of HIV in their semen or vaginal fluids, as well as other conditions that lead to higher infectivity.

What can decrease the spread of HIV through sex?

Correct and consistent use of condoms significantly reduces the transmission of HIV. At present, condoms are the most effective method of HIV prevention through the sexual route. Treatment and prevention of STIs can reduce the risk of HIV transmission. STIs particularly not only increase a person’s susceptibility to getting HIV, they also increase an HIV-positive person’s infectivity, making the spread of the infection easier.

What are the conditions for transmission from mother to child?

An HIV-positive woman can pass the virus to her child during pregnancy, delivery, or through breastfeeding. Most often, a foetus is protected from infection while in the uterus, but the presence of some STIs such as syphilis can increase the likelihood of infection. Transmission between mother and child is most likely to occur during delivery when the baby is in contact with the mother’s blood and vaginal secretions. ARVs (antiretroviral drugs) greatly reduce this risk. HIV is also present in breast milk; different studies have found results ranging from a 5% to a 20% chance that the baby may become infected through breast milk. When there is no healthy alternative to breastfeeding, infected mothers are encouraged to breastfeed their children to prevent them from dying of malnutrition or water-borne diseases instead. The risks of HIV infection through breastfeeding and the risk of death due to malnutrition need to balanced and carefully considered in such situations.

What can reduce the risk of transmission of HIV from mother to child?

Using antiretroviral medicines during pregnancy and delivery can prevent transmission from mother to child. This method, combined with safe delivery practices and counselling and support for infant feeding methods can significantly reduce the transmission of the virus from mothers to their infants. It is crucial for pregnant women to know if they are HIV-positive.

Why do people now prefer to use the term parent-to-child transmission instead of mother-to-child transmission?

It has been argued that the term mother-to-child transmission puts the onus of infection of a child on the mother, which may often not be the case. Parent-to-child infection implies that the child could have got infected by the father via the mother. The use of this term holds both parents responsible for taking the necessary precautions to prevent transmission of infection to the child in case one or both parents are HIV-positive.

How can a person find out if a baby has HIV?

Most common HIV tests do not test for the virus itself, but for the presence of HIV antibodies. Since all infants carry their mother’s antibodies for the first several months of life, it is difficult to determine if an infant born to an HIV-positive mother has HIV. All the babies of HIV-positive women will have HIV antibodies in their systems for 9 to 18 months, therefore, testing infants at 9 months and again at 18 months is recommended. In addition, all infants born to HIV-positive mothers should receive regular check-ups for up to 18 months. Due to the complications in determining if the infant is HIV-positive, the infant’s health and nutrition must be carefully monitored and the use of preventative medicines may be necessary.

What are the conditions for transmission of HIV through blood and blood products?

Injecting drug use, blood transfusion, and needle sticks are the primary methods of transmitting HIV through blood or blood products. Sharing injecting needles and/or syringes for drug use is a very effective way of transmitting HIV. When infected blood is drawn into a needle while using a syringe and that needle is then used by someone else, the second person is effectively injecting HIV directly into his or her blood. Transfusion of blood infected with HIV, organ or tissue transplants are all ways of spreading HIV. Those subjected to needle stick injuries or blood splashes to the eyes or mouth in the healthcare setting are at low risk of contracting HIV.

What can be done to prevent the transmission of HIV by blood or blood products?

Single-use and proper disposal of syringes and needles can drastically reduce the spread of HIV among injecting drug users. Strict criteria and testing of blood for transfusion and organ and tissue donation can help reduce the risk of HIV transmission, as can blood safety and precautionary guidelines in healthcare settings to avoid risk incidents.

Sex workers/intravenous drug users/truck drivers are the main carriers of the HIV virus, and are the main cause of HIV. True or false?

False. It is not a particular group, but types of behaviour (for example, unprotected anal sex with person/s whose HIV status is not known) that puts a person at risk for HIV. HIV can infect a sex worker, truck driver, married woman in a monogamous relationship, or a child receiving a blood transfusion.

Can HIV/AIDS affect married men and women?

Yes, being married does not protect a person from HIV/AIDS.

Can you tell by looking at someone if they have HIV?

No. It can take up to 8-10 years or even more before someone with HIV begins to show symptoms. Now, with better access to treatment options and better lifestyle and nutrition choices, the advent of opportunistic infections may be even further delayed. Also, the ‘symptoms’ that may appear are to do with Opportunistic Infections.

Can a mosquito spread HIV?

Mosquitoes cannot spread HIV. Extensive research on this question has proven this.

Is HIV a strong or fragile virus?

HIV is a strong virus inside the body, but fragile outside the body. It survives only for a few minutes outside the body. It can only survive in moist conditions, which is why it is transmitted through bodily fluids such as blood, semen, vaginal secretion, or breast milk. It cannot penetrate through unbroken skin and condoms. HIV is sensitive to fluctuations in temperature and the presence of oxygen. One place that HIV has been known to survive for a long time is in drug injection syringes since these are airtight and often contain blood from the injector.

This is an excerpt from TARSHI’s The Orange Book: A Teachers’ Workbook on Sexuality Education. You can find a copy of the book here.