Ethnomedical survey of plants used for the management of HIV and AIDS-related conditions in Mbulu District, Tanzania

1 Department of Clinical Pharmacy and Pharmacology, School of Pharmacy, Muhimbili University of Health and Allied Sciences, P. O. Box 65013, Dar es Salaam, Tanzania. 2 Department of Biological and Pre-clinical Studies, Institute of Traditional Medicine, Muhimbili University of Health and Allied Sciences, P. O. Box 65001, Dar es Salaam, Tanzania. 3 Department of Natural Products Development and Formulations, Institute of Traditional Medicine, Muhimbili University of Health and Allied Sciences, P. O. Box 65001, Dar es Salaam, Tanzania. 4 Department of Biological Sciences, University of Botswana, Private Bag UB 00704, Garborone, Botswana.


INTRODUCTION
Due to advances in the development of highly active antiretroviral therapy (HAART), HIV/AIDS has become a *Corresponding author. E-mail: marealle2010@gmail.com.
Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution License 4.0 International License manageable chronic condition. However, HIV infection is still a disease of public health concern which in 2018 accounted for 770 000 deaths globally (WHO, 2018). Among reported worldwide HIV cases, more than 70% are from Sub Saharan Africa. In Tanzania, the prevalence of HIV is about 5.1% and in 2017 it was estimated that 1.5 million people were living with HIV, 65 000 new infections were reported and a total of 32 000 AIDSrelated deaths occurred (NBS, 2017;WHO, 2018). The prevalence of HIV in Tanzania by regions ranges from 0% in some areas of Unguja and Pemba to 11.4% in Njombe region (NBS, 2017). Manyara Region is currently among regions with low prevalence of HIV in Tanzania mainland. However, in 2002, Manyara Region was among the two regions with the highest prevalence of HIV based on prevalence estimated among blood donors (Tanzania, 2002). At that time, the highest prevalence was noted in Kagera (18.6%), followed closely by Manyara (17.5%) and Iringa (14.1%) regions. In the same year, the prevalence among females by region was highest in Manyara (19.8%), followed by Dar es Salaam (18.9%) and Iringa (18.4%) (Tanzania, 2002). However, currently the prevalence of HIV in Manyara Region is significantly lower than the national HIV prevalence with the most recent prevalence of 1.5 % as per 2011-2012 HIV impact survey and 2.3% as per 2016-2017 HIV impact survey (NBS, 2017;Tanzania, 2011).
The World Health Organization (WHO) estimates that about three quarter of the population in some African countries still relies on medicinal plants for their primary health care (WHO, 2008). The great biodiversity in sub-Sahara Africa has provided the indigenous people with a range of plants that are used for traditional medicinal purposes. Mbulu District in Manyara Region is inhabited by people of different tribes, particularly Iraqw", Datooga and Hadzabe with reported use of herbal medicines for treatment and management of their health challenges (Patel and Mwamhanga, 2014;Qwarse et al., 2018). The Hadzabe are hunter-gatherers who live in the eastern rift valley in Northern Tanzania and for most of the time they have relied on natural resources (Marlowe, 2002). This remote area with poor infrastructure has not been extensively reached for the inventory of medicinal plants. The rural community is almost totally dependent on traditional medicine for their health care needs. It is therefore, reasonable to speculate that the use of alternative health seeking and coping strategies in Mbulu, including the use of herbal therapies, may have contributed to the progressive reduction of HIV/AIDS prevalence.
Despite the huge biodiversity and the history of use of medicinal plants in Manyara Region, to the best of our knowledge, no study has documented plants used for the management of HIV and AIDS-related conditions. Therefore, the purpose of this study was to identify medicinal plants used for the management of HIV and AIDS-related conditions and to compile supplementary data on ethnomedical used and pharmacological activities of respective plants.

Study area
Mbulu District is one amongst the six districts in Manyara Region, northeastern Tanzania (Figure 1), with an estimated population of 320 279, according to the latest Tanzania National Census of 2012 (NBS, 2013). The district is bordered to the north by the Arusha region and lake Eyasi, to the east by the Babati rural district, to the south by the Hanang district, and to the west by the Singida region. People of different ethnicities inhabit this district, particularly Iraqw" (also called the Wambulu) one of the earliest agro-pastoralists who migrated south from the region of Ethiopia to Tanzania. The other indigenous ethnic groups are the Hadzabe, living in Yaeda chini and the Datooga people. Local inhabitants engage mainly in agriculture, livestock keeping, farming activities and hunting. There are plantations of onions and wheat in many places of Manyara region which attract many business people from across the country and from neighboring countries. Seasonal open markets for livestock and the presence of the Haydom Lutheran hospital, which provides specialized medical care are among factors that attract people from other parts of the region and the country to visit the district.

Study design
This was a qualitative ethnomedical survey conducted in May 2019. This study design was selected as it offers opportunity for a homogeneous exploration, raise more issues through broad and open-ended inquiry (Choy, 2014). The study employed a purposive sampling method in which selection of respondents only included THPs recognized by Health authorities in the office of Mbulu District Medical Officer (DMO). This was important to reduce the likelihood of interacting with fake or inexperienced THPs. Acknowledging the contribution of THPs in health care provision in Tanzania, the Ministry responsible for health is currently advocating registration of THPs through the offices of DMOs all over the country. The legitimacy of a THP is checked well before he/she is registered through the involvement of witnesses like neighbors, village and ward officials where the THP resides or has been practicing. During the conduct of this study, the coordinator from the office of the DMO responsible for the registration of THPs was engaged to locate the THPs, and kindly offered translation services when it was required.

Data collection
The study employed face-to-face interviews to document ethnomedical information about plants used for management of selected disease conditions mainly HIV and AIDS-related conditions using a semi-structured questionnaire. A narrative of symptoms helped in listing plants used by the THPs to treat HIV/AIDS-related conditions. The first sections of the questionnaire sought to gather demographic information about the THPs, and the conditions that the THPs are confident of treating/managing. The other sections aimed at documenting plants that are used to manage conditions/symptoms of HIV and AIDS-related diseases including; tuberculosis, Herpes zoster infection (commonly known as "mkanda wa jeshi" in Kiswahili and characterized by a pruritic rash around the chest or stomach), persistent cough, cough associated with chest pain, skin rashes, frequent fevers, chronic diarrhea, chronic wounds, genital warts and wasting.

Data analysis
Data were entered into Excel spreadsheet and summarized using descriptive statistics. The descriptive statistics were applied to identify the number and percentage of species, genera and families of medicinal plants. They were also applied to identify the percentage distribution of plant parts used and diseases treated by the identified medicinal plants. The graphs were plotted by GraphPad prism software version 8.

Ethical approval and consent to participate
This study was awarded Ethical clearance by the MUHAS institutional review board (Ethical clearance No. 2018-04-04/AEC/Vol. XII/87; Dated, 4 th April 2018). Permission to conduct the study in Mbulu District was sought from all government authorities from the district to village level. All THPs gave prior informed consent before they were interviewed.

Socio-demographic characteristics of the THPs
The study interviewed six THPs from Mbulu District. Four of them were males and two were females. Six different wards of Mbulu District were visited for the survey including Gidhim, Labay, Endamilay, Masqaroda, Yaeda chini and Haydom. The wards were chosen purposively based on the availability of THPs recognized by the coordinators from the office of DMO responsible for

General conditions treated by THPs
THPs are diverse in their professional skills and are sometimes specialized. In order to gain an insight in the overall expertise all THPs participating in this study were asked to mention disease conditions which they generally treat. All six interviewed THPs reported to be able to treat at least one type of cancer. The majority stated also being capable of treating other conditions including gonorrhea 5(83%), typhoid fever 5(83%) and syphilis 4 (67%).

Medicinal plant species documented
This study documented 37 plant species used in Mbulu for the management of a variety of human disease conditions, majority of which (81%) were for management of HIV and AIDS-related conditions ( Figure 1). The plants represent 23 families and the families with the highest number of species documented were Acanthaceae, Caesalpinaceae, Compositae and Verbenaceae with 3 species each ( Figure 2). Out of the 37 reported plant species, 23 (62%) had related cited ethnomedical uses, 23 (62%) had scientifically proven related cited biological activity and 12 (32%) had been reported to have varying activities

Plant part used, dosage forms and routes of administration
The most frequently used plant parts by the THPs were roots (58.1%) whereby 37.2% use root barks and 20.9% reported to use whole roots. The other plant part used is stem bark (23.3%) followed by leaves (11.6%) ( Figure 3). The main method of preparation used by the THPs was decoction (52%), followed by dry powder (38.1%) ( Figure  4).The methods of drug administration were oral application (81.1%) and topical application, mainly used for wounds and other skin infections (19.9%).
C. abbreviata and Plumbago zeylanica L. were among 10 plants ethnobotanically identified in Botswana and tested by our collaborators for anti-HIV activity in recent years. Both plants were among 3 plants with the highest ability to inhibit HIV-1c (MJ 4 ) replication as measured by p-24 antigen Elisa kit (Leteane et al., 2012). Their study revealed that C. abbreviata subsp. beareana (Holmes) Brenan inhibited HIV-1c in a concentration dependent manner but the activity of P. zeylanica L. was linked to its tannin content. They also tested another plant Cassia sieberiana which is in the same genus as C. abbreviata subsp. beareana (Holmes) Brenan and had the highest ability to inhibit HIV-1c replication among the 10 tested plants in a concentration dependent manner. During the survey in Manyara other plants from the Cassia genus were also reported and collected which include Cassia didymobotrya and Cassia singueana. C. didymobotrya has been reported to have no anti-HIV activity as it failed to protect the MT-4 cells from HIV cytopathy measured by MTT (Cos et al., 2002). However, there are no reports on anti-HIV activity of the other plant Cassia singueana. In Mbulu, Tanzania, C. abbreviata is mixed with several other plants for treatment of diarrhea and some of these plants have been proven scientifically to have varying antimicrobial activities including anti-HIV-1 activity. These plants include Elaeodendron buchananii, Ozoroa insignis, Ximenia americana and Zanha africana. Ximenia americana has been reported to have ability to inhibit HIV-1 replication (Maroyi, 2014). Therefore, there is a need to test the individual plants and combinations to see if the combinations will have improved antimicrobial and/or anti-HIV activity.
High percentage of the reported plant species (62%) had similar cited ethnomedical uses elsewhere and 62% have similar proven biological activities. All interviewed THPs in Mbulu reported to have ability to treat cancer and majority reported to be able to treat STIs (STIs), typhoid fever and brucellosis, diseases which are relevant in their area. Therefore, the results are indicative of how strong the THPs in Mbulu district are managing infections and cancers. This is supported by the big number of patients these THPs are receiving and attending per month. Some other reported plant species have not been screened for anti-HIV activity but some species from the same genus have been tested and found to have anti-HIV activity. A good example is Vernonia glabra, used in Mbulu for management of STIs and is confirmed to have weak antimalarial and antimicrobial activity (Frank, 2012;Kitonde et al., 2012;Ramadhani et al., 2015) but has no reports on anti-HIV activity. However, Vernonia amygdalina and Vernonia  Stem bark decoction is used in Tanzania for Cough and chest infections (Maregesi et al., 2007). In Uganda roots and leaves decoction is drunk for yellow fever (Tugume et al., 2016).
Anti-HIV/antiviral, antimicrobial, anticancer, wound-healing and anthelmintic properties (Chothani and Vaghasiya, 2011;Hussein et al., 1999;Kabbashi, 2015;Runyoro et al., 2006). An oral administration of the aqueous extract for the treatment of HIV patients has shown good results (Chothani and Vaghasiya, 2011). Decoction. One tea cup is taken twice a day for two days.
In Tanzania root decoction or infusion of leaves is drunk for treatment of dysentery and it is very potent for several infectious diseases (Maregesi et al., 2007). In Ethiopia, it is used for wound healing and cancer (Bitew et al., 2019;Tuasha et al., 2018).

Frequent fevers, epilepsy Roots
Decoction. One tea cup is taken twice a day until recovered. Used in Zimbabwe for STIs (Kambizi and Afolayan, 2001), in Mozambique for eye infection, stomach ache, diarrhea, and malaria (Ribeiro et al., 2010). Used in Botswana for general cleansing, abdominal pain, womb problems, menstrual pains, and STIs (Leteane et al., 2012).

Leaves, roots Decoction
In Kenya leaves and roots are used for treatment of cancer, skin diseases, malaria, gonorrhea, ring worms, emetic, excess bile and as a purgative (Jeruto et al., 2008). In Rwanda it is used against ascariasis, and neuropsychopathy (Cos et al., 2002). In Tanzania it is used for treatment of anemia, as laxative and antihelmintic (Kamuhabwa et al., 2000).
Strong activity against Plasmodium berghei (Deressa et al., 2010).  (Njoroge and Bussmann, 2007). In Kenya the bark decoction is used for management of wounds and whooping cough (Peter et al., 2015). It is also used for syphilis, anthrax and snakebites (Kariuki et al., 2014).

Fungal infections with Tinea versicolor
Aerial parts White sap from the fresh leaves and stem applied locally
Antimicrobial and antinematodal activity (Tesfaye and Girma, 2017). In Tanzania the stem bark and root decoction is used in dysentery and jaundice (Maregesi et al., 2007). In Uganda it is used in the management of HIV/AIDSrelated conditions (Lamorde et al., 2010;Nyamukuru et al., 2017). In Rwanda it is used to treat dysentery (Maikere-Faniyo et al., 1989) . In Zimbabwe it is used in the It contains Anti-HIV-1 alkaloids (Mohammed et al., 2012)  treatment of STIs (Kambizi and Afolayan, 2001). In Ethiopia it is used for tonsillitis (Kebebew and Mohamed, 2017). In Ethiopia it is used for treatment of eye infections (Kebebew and Mohamed, 2017;Temam and Dillo, 2016), while in Angola the barks are used to treat febrile conditions (Fernandes et al., 2015).

Roots
One tea cup of decoction is taken before meal once a day for 3 days It is used in Burundi for treatment of diarrheal diseases, leaves or aerial parts used for treatment of Skin mycosis, varicella, and dysentery (Ngezahayo et al., 2015;Ngezahayo et al., 2017).
Very toxic to brine shrimps and cytotoxic to human hepatocelullar carcinoma, human mammary adenocarcinoma and human hepatocellular carcinoma cells (Moshi et al., 2009;Rea, 2003) .

Root bark Decoction
Used in the treatment of gonorrhea and candidiasis in Namibia (Chinsembu, 2010;Hedimbi and Chinsembu, 2012). Used for treatment of diarrhea in South Africa (Semenya and Maroyi, 2012). It is used as antiabortifacient, and in the treatment of HIV/AIDS, menstrual cycle irregularities, stabbing heart, stomach ache, wounds in Mozambique (Ribeiro et al., 2010).

Disease conditions/symptoms
Percentage adoensis from the same genus have been reported to have anti-HIV-1 activity (Toyang and Verpoorte, 2013). Another plant is Terminalia brownii which is used in Mbulu for treatment of pneumonia. The plant is proven to have antimicrobial activity against a big number of microorganisms (Machumi et al., 2013;Salih et al., 2017). However, the plant has not been tested for anti-HIV activity but Terminalia sericea from the same genus has been reported to have strong HIV-1 reverse transcriptase inhibitory activity (Tshikalange et al., 2008). Zanthoxylum chalybeum, used for various infections in Mbulu and elsewhere, has no reports on anti-HIV activity while Zanthoxylum davyi, a member of the same genus, has anti-HIV activity (Tshikalange et al., 2008). In Mbulu the plant in some cases is combined with Conyza pyrrhopappa leaves or roots for treatment of persistent cough and therefore, the plant and the combination are worthy of screening for antimicrobial, anti-HIV and antimycobacterial activity. Despite the previous reported ethnomedicinal uses of some of the reported plants, reports on clinical evaluation of the patients who were treated with these plants are lacking. To support the traditional uses of these plants clinical evaluation in patients is important.

Conclusion
This survey identified sixteen medicinal plants with new ethnomedical uses related to HIV and AIDS conditions. Ten of the documented plants had no reported biological reports related to HIV and AIDS-related conditions. Reports from the literature provide a strong support to the traditional medicinal use practices of Mbulu THPs for the management of HIV and AIDS-related conditions. Although the results of this study are consistent with ethnomedical and antimicrobial data from the literature, more studies are needed to validate the antimicrobial efficacies, pharmacological, cytotoxicity, and active phytochemicals in the plants.