**5. HIV/AIDS prevention strategies, how well have they worked?**

There are three major strategies of HIV prevention, namely, education or knowledge base, contraceptives, and antiretroviral treatment.

#### **5.1. Peer education**

strain identified in at least three individuals who have no direct epidemiological relationship. Three full-length genomic sequences are required but two complete genomes together with partial sequences of a third strain could also define a new subtype, sub-subtype, or CRF. CRFs are derived from recombination between viruses of different subtypes which are each given a

> 4\_BG,CRF03\_AB, 31\_BC,CFR06/18\_CPX

53/54/55/58/59\_01B

CRF11/45/49/37/36\_CPX

CRF05\_DF,CRF13\_CPX,

E CRF01\_AE\* Africa [55]

CRF32\_06A1,CRF33/34\_01B,C RF35\_AD,CRF38/39/40/42/44/ 46/47/70/71/72\_BF,CRF43\_02G

CRF50\_A1D,CRF60/61/62/64\_

CRF04/06/18/27\_CPX,CRF21\_

BC,CRF17\_BF1CRF 49\_01B,CRF63\_02A1

P:Pending West-Central Africa, Cameroon

O:Outlier Cameroon [58]

A None

I CRF04\_CPX Only in central America [57]

F (F1 F2) CRF12\_BF1,CRF22\_01A1,CRF 25\_CPX,CRF26\_AU

<sup>G</sup> CRF02\_AG,CRF09/56/65\_CPX

CRF07/8\_BC,CRF15/48/51/52/

**CRFs GEOGRAPHICAL SPREAD**

[55]

CRF16\_A2D,CRF19\_CPX Eastern and Central Africa [55]

,CRF20/23/24\_BG Africa and Central Europe [56]

A2D Congo DR and Cameroon [56]

[59]

West Africa ,Cuba[52,53,54]

Europe, Japan, Thailand, Australia, the Americas [55]

S/E Africa, India, Nepal, China

Central Africa, S. America, Eastern Europe [56]

Central Africa [56]

Caribbean [56]

North, Central and W. Africa

number. CRF12\_BF, for example, is a recombination between subtypes B and F.

<sup>C</sup> CRF10/41\_CD,

**SUBTYPE(subsubtype)**

I M: Major (90%) A*(A1,A2A3)* CRF19\_CPX,CRF01\_AE,CFR1

8 Trends in Basic and Therapeutic Options in HIV Infection - Towards a Functional Cure

B

D

H

J

K

N:Non- M,Non-O

**HIV type**

II

**GROUP (%)**

Amongst the many ways of curbing the onslaught of the HIV, one of the most vital is educating the populace about the disease and its transmission dynamics. This significantly prevents reinfection and protects those who are not already infected [63, 64, 65]. Therefore, inadequate knowledge of the disease transmission equals resultant failure of all the measures originally put together to tackle the spread of the disease. In a research conducted in 2006 to access the effect of prior knowledge of HIV transmission relative to the number of occurrence of the infection in Boston, USA, it was found that a significant proportion of the infected people are those with significantly little or no knowledge of the disease or its mode of transmission [66]. Increase in HIV education, particularly amongst young people, remains the most effective way of tackling the HIV onslaught. Where this form of education is limited, the disease is known to prevail [67, 68] as also noted from various data in sub-Saharan Africa. Education on HIV/ AIDS plays a major role in controlling the spread of the disease amongst young people, which consequently determines the global spread of infection. HIV infection has been captured as the second most prevalent killer amongst young people. As of 2012, one-third of the global new HIV infection was discovered to be amongst young people, with total infection of about 780,000 and concentrated within 15–24 age group [69]. This number has obviously dropped down from 2012 to present due to vigorous and continuous education campaigns but, even so, HIV/AIDS deaths amongst the young people worldwide are still at an alarming rate [70, 71]. Proper education enables young people and married adults to better protect themselves against the sexually transmitted route of HIV infection, vertical transmission, and also behaviours such as intravenous drug use [72]. So significant was the global implication of HIV/ AIDS infection on young people that it was opined that HIV education should be dispensed even to healthy ones.

#### **5.2. Antiretroviral prophylaxis**

In poor-resource settings, it is not uncommon to use antiviral therapy as a means of controlling the spread of infection. Experiments however showed that the administration of antiviral therapy, although it has a considerable control rate on HIV infection, is limited in its cost. Many HIV populations do not have access to ART [73] and to others are very expensive [74]. In Nigeria for instance the price of generic ART reported in 2001 could be over 10 times more expensive in comparison with Asian countries and about 79% lower in some European countries [75]. When antiviral therapy is considered as a chosen measure for HIV treatment, an additional use of these therapeutic agents serves as a preventive measure rather than a treatment option. The application of ART at a specific stage of disease progression (measured by computerised simulation incorporating CD4 count and HIV RNA level) has proved to be cost effective [76]. HIV prophylaxis treatment refers to the institution of measures taken to protect a person from HIV infection to which the individual has been anticipated or is liable to be exposed to HIV. HIV prophylaxis could either be post or pre-treatment option based. According to the US CDC, pre-exposure prophylaxis (PrEP) is designed for individuals who do not have HIV but who are at substantial risk of getting it to prevent HIV infection by taking an antiretroviral drug every day [77]. Truvada which contains two HIV drugs (tenofovir and emtricitabine) is usually prescribed [78]. On exposure to HIV through sex or injection drug use, these drugs can work to keep the virus from establishing a permanent infection. PrEP has been shown to reduce the risk of HIV infection in people who are at high risk by up to 92% when adhered to for at least 3 months [77]. Similarly, WHO describes post-exposure prophy‐ laxis (PEP) as contrasted by PrEP as a short-term antiretroviral treatment to reduce the likelihood of HIV infection after potential exposure, either occupationally or through sexual intercourse [79,80]. Post-exposure prophylaxis (PEP) involves taking a 28-day course of ARVs, for adults Tenofovir combined with either lamivudine (3TC) or emtricitabine (FTC) is prescri‐ bed. The recommended third drug by WHO is ritonavir-boosted lopinavir (LPV/r), which is also a preferred drug for HIV treatment. Zidovidune (AZT) and lamivudine (3TC) backbone drugs are used for children aged 10 or below, with ritonavir-boosted lopinavir (LPV/r) recommended as the third drug choice [81-84]. As effective as this preventive option may be, it faces challenges of adherences which has reduced its efficacy to less than 56%. Another challenge is the accessibility of the drug to individuals and accurate timing of exposure.

Limited studies on supply and distribution of antiviral drugs in poor-resource areas indicated that the mechanisms of supply and delivery of these drugs are not cost-effective [85-87]. The most significant concern is rural population having access to HIV antiviral drugs and the availability of laboratory facilities to monitor viral loads of patients on antiviral drug as response to therapy and for full HIV clinical management. One of the standard laboratory interventions used in the developed countries to monitor patients receiving antiviral drugs is the plasma viral load monitoring assay [88] which is not readily accessible to the wider population of HIV patients in resource-poor regions [89].

#### **5.3. Contraceptives**

Contraceptives may simply be understood as devices or pills used to prevent unwanted pregnancies and diseases mostly sexually transmitted. These can be in the form of drugs, hormones, or devices such as condoms and intrauterine devices (IUD). Evidently, hormonal contraceptives and pills do not protect against HIV or other sexually transmitted infections (STI). At present there are no contraceptives, with the exception of condoms (male and female), that protect against HIV infection [90]. Since the only forms of birth control that will protect against HIV are abstaining from vaginal (and anal) sex or using condoms while having sex, WHO therefore recommends dual protection technique for unwanted pregnancy and HIV prevention [91]. Birth control options that do not protect against HIV infection include oral contraceptives, birth control shot (injection of the hormone Depot Medroxyprogesterone Acetate (*DMPA*) in the arm to release progestin)/Depo-provera, morning after pill (Levonor‐ gestrel or Ulipristal acetate) used after sexual activity, implants (implanon/norplant), IUDs which release progestin, female condoms such as diaphragm/vagina ring/sponge/cervical cap, withdrawal and spermicides. Currently, a new intravaginal ring that helps prevent pregnancy while simultaneously releasing low doses of an antiretroviral drug that reduces a woman's risk of contracting both HIV and genital herpes has been designed [92,93]. This device releases doses of the contraceptive Levonorgestrel and the antiretroviral HIV medication tenofovir after being inserted in the vagina for 90 days and has demonstrated a 39% protection against HIV infection in women [93]. It is obvious that many contraceptive pills may not be compatible with ARTs, the widely prescribed antiretroviral drug efavirenz substantially reduces levels of the hormonal contraceptive Levonorgestrel [94] and increases the risk of HIV infection [95,96].
