HIV Status in Zanzibar
The HIV pandemic has not spared any continent and/or region of the world. Sub-Saharan countries have been the hardest hit, resulting in significantly higher negative outcomes including in ill-health, many deaths and reduced economic productivity. Generally, the United Republic of Tanzania and Zanzibar have not been spared from the challenges and effects of the HIV epidemic either. Each part of the Republic has witnessed and documented variations in the character and pattern of the HIV epidemic. The HIV epidemic in Mainland Tanzania is of the generalised type, largely driven by heterosexual transmission. Based on HIV surveillance surveys both at the National and ANC level, and subsequent assessment of some sub-populations, the HIV epidemic in Zanzibar has signs of being inclined to the concentrated type, and largely driven by MARPs. In-depth analysis of other diseases with a similar transmission profile, such as Hepatitis C, is suggestive of the fact that Zanzibar is not yet experiencing a mature concentrated HIV epidemic. And to ensure the full character of the HIV epidemic in Zanzibar is well characterized and understood to help in better planning and effective implementation of interventions, there is need to undertake an in-depth assessment of risk factors or drivers of the HIV epidemic in the country. This could be done through a national mode of HIV transmission study.
In 1986, the Isles of Zanzibar documented the index case of AIDS at Mnazi Mmoja Hospital. Henceforth, the country has continued to witness a growth in the cumulative number of PLHIV. Initial surveillance reports suggested the potential factors driving the epidemic in Zanzibar as being similar to those witnessed in countries/areas with generalised HIV epidemic. Hence, heterosexual HIV transmission was initially predominantly singled out as the sole mode of transmission on the Isles. The HIV epidemic has spread to all districts in Zanzibar but at unequal pace, levels and magnitude. With limited institutionalised surveillance system and available evidence characterizing the epidemic as generalized, the efforts made to combat the HIV epidemic were targeted at the addressing only the risk of heterosexual transmission.
In 2002, stakeholders queried the quality and validity of data that were collected to define the HIV epidemic in Zanzibar. In response to this, a validation survey was carried out in 2002 and the results put the national HIV prevalence at below one percent, and indications of a higher probability of the epidemic in Zanzibar being of the concentrated type. This led to revision of the surveillance protocol to address the inherent limitations in the national HIV surveillance system in an attempt to help gather relevant data to more accurately define the prevailing epidemic in Zanzibar. In addition, based on the above observations, the Integrated Behavioural and Biological Surveillance Surveys (IBBSS) have been institutionalised in Zanzibar. The IBBSS aims at equipping Zanzibar with the ability to monitor HIV and STIs in the general population as well as among some of the key identified most-at-risk populations (MARPs).
HIV infection patterns in the general population (Zanzibar)
The Tanzania HIV/Malaria Indicator Survey (THMIS III) have documented an HIV prevalence of 1.0 percent in the sexually active general population in Zanzibar. The HIV prevalence is higher among women compared to men in Zanzibar and estimates put this at 1.1% Vs 0.9% respectively (THMIS III). Projections from these observations put the estimated number of people living with HIV (PLHIV) in Zanzibar at 10,000. The available evidence shows the HIV epidemic in Zanzibar varies by sex of the individual and Island of residence.. HIV prevalence is higher among women compared to men (1.1% and 0.9% respectively) and higher in Unguja compared to Pemba (0.8% by 0.3 %) Island. Also among young Zanzibaris aged 15-24 years whose HIV prevalence is estimated at 0.2 percent, there are three females infected for male (0.3% Vs 0.1% respectively) in this age bracket.
As outlined earlier, the inherent limitations and nature of DHS in potentially concentrated epidemics, as the case may be in Zanzibar, could lead to a limited base of information on the actual context. To respond to that limitation, additional surveillance methods (such as Respondent Driven Sampling Techniques-RDS and Snowball sampling methods) to assess HIV infections patterns among MARPs have been applied in Zanzibar.
High Risk behaviors (sexual and drug related behaviours) among MARPs
There is high HIV and other STI prevalence among MARPs (MSMs, FSWs and IDUs) because of their higher risk behaviour (including unsafe sex and drug abuse practices) compared to the general population. Various studies conducted among MARPs in Zanzibar have documented high sexual and drug related risk behavior. These include the following in the recognized sub-groups:
According to the 2007 IBBS survey the HIV prevalence among people who inject drugs in Zanzibar is 16.0%. The prevalence of Hepatitis B virus is 6.5 percent; Hepatitis C virus - 26.9 percent; and Syphilis – 0.3 percent. Among PWIDs who tested positive for HIV, 45.1% also tested positive for HCV infection.
The behaviour of sex between males is present in all societies. In Zanzibar the behaviour of male-male sex is highly stigmatised in line with cultural and religious beliefs. While some men who have sex with men do so because it aligns with their sexual preference, others have sex with men for financial reasons although they are primarily attracted to women. This includes transactional sex for money or goods or opportunity. As reported in the 2007 IBBS the median age of sexual debut for men who have sex with men in Zanzibar was 18 years and the majority of MSM (59.5%) reported their first sexual partner was a man.
Female sex work is Zanzibar is more common in Unguja than Pemba, and is often associated with the tourism industry areas, though significant trading of sex also occurs in the local population. Female sex workers typically range in age from 15 – mid 50s and the median age of women selling sex is in the middle 20s. The majority of female sex workers report earning less than 120,000 TZS monthly, with 25.6% reporting a personal income of less than 50,000 TZS. Only 14.4% of female sex workers in the 2007 IBBS had a monthly income of more than 200,000 TZS. The majority of female sex workers (73.9%) earn their income primarily from sex work while 20.6% of female sex workers also report earning income through private income generating activities. According to the 2007 IBBS survey the HIV prevalence among female sex workers in Zanzibar is 10.8%. The prevalence of Hepatitis B virus is 5.1 percent; Hepatitis C virus - 1.9 percent; and Syphilis – 1.3 percent.
HIV prevalence is higher among female sex workers reporting less education and selling sex for a longer period: 16.7% of female sex workers who completed 1 to 7 years of school were HIV-infected compared with 3.1% of those who completed 8 to 10 years of school. HIV prevalence was highest among female sex workers who reported selling sex for 10 years or more (28.6%), compared with that of female sex workers who reported selling sex for three years or less (3.6%).
Disconnect between high levels of HIV related knowledge among Zanzibaris and high risk sexual behaviour
THMIS documented high levels of HIV awareness among the studied populations in Unguja and Pemba Islands. HIV related awareness levels in both men and women in Zanzibar is about 99 percent. Despite this, less than 50 percent of both men and women in Zanzibar knew condoms are a HIV prevention intervention/commodity while only 32.9 percent of men and 20.3 percent of women claimed to have used a condom in the last high risk sexual encounter. Non consistent and incorrect use of condoms by those engaged in risk sex behaviour might fuel the epidemic in Zanzibar.
There is now evidence that young women in Zanzibar are getting exposed to sex at an early age, and those involved are often oblivious of the dangers this poses to tem especially the risk of HIV infection. About 6 percent and 13 percent of young people aged 15-24 years have had pre-marital sex, and which in most instances, is unprotected. This pre-disposes these young people to higher risks of contracting STDs and HIV infection. Similarly, unprotected sex among married couples who have multiple concurrent sexual partnerships poses challenges to prevention efforts and could aggravate the HIV epidemic in Zanzibar.
High mobility and high migration by Zanzibaris
Internal and external migration is common among Zanzibaris and to those residing within the vicinity of Zanzibar. These include business people, migrant workers (pre-dominantly hoteliers), tourists and MARPs (all MARPs sub-populations have been documented to be highly mobile). Based on circumstances these might not have power to protect themselves and some might participate in high-risk sexual activity for their survival. Frequent access to proper and quality health services is also quite limited among these groups.
The Socioeconomic Impact of HIV in Zanzibar
As is the case in other neighbouring Sub-Saharan African countries, the HIV epidemic has had a negative impact on Zanzibar, and effective strategies are needed to respond. Many challenges stand in the way of the development and implementation of effective strategies due to the nature and type of the epidemic in Zanzibar, and in part, as a result of limited reliable data. There are few assessments that have done to look in greater detail at the impact of HIV epidemic on the Islands. In view of this, the HIV effects at household and national levels are yet to be fully defined.