Organic essential oils, indigenous cold pressed oils, herbs and spices in sub-Saharan Africa

The advancement of the livestock farming in sub-Saharan Africa is restricted by tick infestation. With conventional pesticides posing a threat to human and the environment, natural products are alternative anti-tick source. This study characterized the essential oils from Tithonia diversifolia, Lavandula angustifolia and Cymbopogon citratus leaves by GC-MS and, for acaricidal and repellence of R. appendiculatus. GC-MS analysis detected various chemical compounds, some of the isolated compounds have anti-tick properties. The repellence of T. diversifolia essential oil at 5% v/v was the weakest against adult ticks. All essential oils at 15% v/v paralysed nymph after 20 mins, with C. citratus after 24 h causing high mortality of nymph and adult ticks. Exposure to L. angustifolia did not achieve 50% mortality after 24 h. All essential oils caused complete inhibition of moulting of engorged larvae. The study demonstrated that the essential oils of the ethno-veterinary plants may be a source of anti-ticks agents.

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Toxicity and Oviposition Deterrent Activities of Thyme Essential Oils against Anopheles arabiensis

Psyche A Journal of Entomology ◽

10.1155/2021/6684156 ◽

2021 ◽

Vol 2021 ◽

pp. 1-7

Author(s):

Destaw Damtie ◽

Yalemtsehay Mekonnen

Keyword(s):

Essential Oils ◽

Anopheles Arabiensis ◽

Activity Index ◽

Lethal Dose ◽

Environmental Issues ◽

Field Trials ◽

Sub Saharan Africa ◽

Oviposition Deterrent ◽

Small Doses ◽

Sub Saharan

Background. Malaria is one of the deadliest mosquito-borne diseases in sub-Saharan Africa and Ethiopia. Owing to their costs and environmental issues, synthetic insecticides are poor choices to control mosquitoes. Plant-based products can be considered as safe and biodegradable alternatives. The present study aimed to test the toxicity and oviposition deterrent activities of Thymus serrulatus and Thymus schimperi essential oils (EOs) against Anopheles arabiensis. Methods. Thyme EOs were extracted by hydrodistillation using the Clevenger-type apparatus. They were named Tar, Ala, and Yil after the areas of thyme collection Tarmaber, Alamata, and Yilmana Densa, respectively. Laboratory-based tests were used to determine the larvicidal, adulticidal, oviposition deterrent, and half lethal dose (LD50) of each EO. Results. The concentrations of 100 μl/L and 50 μl/L resulted in complete mortalities of larvae and adults, respectively, for all the three Eos considered. The EOs exhibited high repellency with oviposition activity index of −1 (OAI = −1) at concentrations of 50 μl/L (Tar), 100 μl/L (Ala), and 200 μl/L (Yil). Conclusions. The EOs of T. serrulatus and T. schimperi were effective against larvae and adult mosquitoes at small doses and resulted in oviposition deterrence at doses from 50 to 200 μl/L. Thus, these EOs are promising mosquitocides and oviposition deterrents. But, further tests both in the presence of already known and effective deterrents and field trials are required.

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An evaluation of the efficacy of extracts from Xylopia aethiopica and Dennittia tripetala in controlling Dermestes maculatus(degeer) an insect pest of dry stored fish in Calabar, Nigeria

Journal of Aquaculture & Marine Biology ◽

10.15406/jamb.2020.10.00301 ◽

2021 ◽

Vol 10 (1) ◽

pp. 1-6

Author(s):

Fidelis Bekeh Ada

Keyword(s):

Essential Oils ◽

Adult Population ◽

Insect Pest ◽

Chemical Constituent ◽

College Of Education ◽

Sub Saharan Africa ◽

Small Scale ◽

Local Market ◽

Sub Saharan ◽

Xylopia Aethiopica

Laboratory bioassays were conducted in Obudu, Nigeria to evaluate the efficacy of extracts from X.aethiopica and D.tripetala in controlling D.maculatus a primary pest of dry stored fish in sub-saharan Africa. Adult population of D. maculatus was obtained in the laboratory at the Federal college of Education Obudu, to obtain fresh insects for the experimental work. Dried fruits of X.aethiopica (Dunal) and dried seeds of D.tripetala (Bak.f.) were procured from a local market in Obudu for the purpose of the work. 100g each of the spice plants were pounded separately using laboratory pestle and mortar for the extraction of essential oils (EOS). The essential oils extracted were tested for repellence and toxicity against D.maculatus at 10µl per EO in a 4-way Olfactometer. Minitab 15 statistical soft ware was used for the analysis of data. Results indicated that the essential oils (EOS) and their constituent individual compounds were significantly (p<0.05) repellent and toxic to D.maculatus with X.aethiopica more repellent and more toxic to the insect than D.tripelala. The two oils were also observed to inhibit the activities of microbes that usually cause and accelerate delaying in stored fish. This action of the essential oils of the two spice plants and their chemical constituent demonstrated their potentials for development in stored products protection, especially at the small scale resource poor farmer’s level in Nigeria.

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RTS,S/AS01, a vaccine targeting pre-erythrocytic stages of Plasmodium falciparum

Emerging Topics in Life Sciences ◽

10.1042/etls20170101 ◽

2017 ◽

Vol 1 (6) ◽

pp. 533-537

Author(s):

Lorenz von Seidlein ◽

Borimas Hanboonkunupakarn ◽

Podjanee Jittmala ◽

Sasithon Pukrittayakamee

Keyword(s):

Protective Efficacy ◽

Age Groups ◽

Sub Saharan Africa ◽

Phase Iii ◽

European Medicines Agency ◽

Older Children ◽

Pivotal Phase ◽

Malaria Epidemiology ◽

Maximum Benefit ◽

Sub Saharan

RTS,S/AS01 is the most advanced vaccine to prevent malaria. It is safe and moderately effective. A large pivotal phase III trial in over 15 000 young children in sub-Saharan Africa completed in 2014 showed that the vaccine could protect around one-third of children (aged 5–17 months) and one-fourth of infants (aged 6–12 weeks) from uncomplicated falciparum malaria. The European Medicines Agency approved licensing and programmatic roll-out of the RTSS vaccine in malaria endemic countries in sub-Saharan Africa. WHO is planning further studies in a large Malaria Vaccine Implementation Programme, in more than 400 000 young African children. With the changing malaria epidemiology in Africa resulting in older children at risk, alternative modes of employment are under evaluation, for example the use of RTS,S/AS01 in older children as part of seasonal malaria prophylaxis. Another strategy is combining mass drug administrations with mass vaccine campaigns for all age groups in regional malaria elimination campaigns. A phase II trial is ongoing to evaluate the safety and immunogenicity of the RTSS in combination with antimalarial drugs in Thailand. Such novel approaches aim to extract the maximum benefit from the well-documented, short-lasting protective efficacy of RTS,S/AS01.

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Mortality and Society in Sub-Saharan Africa

Population Studies ◽

10.1080/0032472031000147416 ◽

1993 ◽

Vol 47 (3) ◽

pp. 555-556

Author(s):

Lado Ruzicka

Keyword(s):

Sub Saharan Africa ◽

Sub Saharan

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Sub-Saharan Africa

The Military Balance ◽

10.1080/04597228708459635 ◽

1987 ◽

Vol 87 (1) ◽

pp. 118-142

Keyword(s):

Sub Saharan Africa ◽

Sub Saharan

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Adolescent Suicidality as Seen in Rural Northeastern Uganda

Crisis ◽

10.1027/0227-5910/a000059 ◽

2011 ◽

Vol 32 (1) ◽

pp. 43-51 ◽

Cited By ~ 17

Author(s):

Eugene Kinyanda ◽

Ruth Kizza ◽

Jonathan Levin ◽

Sheila Ndyanabangi ◽

Catherine Abbo

Keyword(s):

Low Socioeconomic Status ◽

Sub Saharan Africa ◽

Psychosocial Risk ◽

Psychiatric Nurses ◽

Health Concern ◽

Cross Sectional ◽

Childhood Experiences ◽

Low Socioeconomic ◽

Dsm Iv ◽

Sub Saharan

Background: Suicidal behavior in adolescence is a public health concern and has serious consequences for adolescents and their families. There is, however, a paucity of data on this subject from sub-Saharan Africa, hence the need for this study. Aims: A cross-sectional multistage survey to investigate adolescent suicidality among other things was undertaken in rural northeastern Uganda. Methods: A structured protocol administered by trained psychiatric nurses collected information on sociodemographics, mental disorders (DSM-IV criteria), and psychological and psychosocial risk factors for children aged 3–19 years (N = 1492). For the purposes of this paper, an analysis of a subsample of adolescents (aged 10–19 years; n = 897) was undertaken. Results: Lifetime suicidality in this study was 6.1% (95% CI, 4.6%–7.9%). Conclusions: Factors significantly associated with suicidality included mental disorder, the ecological factor district of residence, factors suggestive of low socioeconomic status, and disadvantaged childhood experiences.

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