Two innovative Grade Six learners from Milestone Group of Schools have developed an animal collar that can alert communities of potential human-wildlife conflicts.

As reported by The Manica Post, the tech-savvy girls, Zoe Mderere and Netariro Vengai, both aged 12, commenced their research while in Grade Four in 2022, and came up with the innovative idea in May 2023.

Their collar alerts community members directly, with an application made available to the community members instead of Zimbabwe Parks and Wildlife Management Authority (ZimParks) officials.

Tsetse flies

The G. m. morsitans Westwood colony, originally derived from pupae collected in Zimbabwe, was established at the Liverpool School of Tropical Medicine in 2004. Flies were reared at 26 ± 2 °C, 68–76% relative humidity, with a 12-h photoperiod. Adult flies were fed three times per week on defibrinated horse blood (TCS Biosciences, Buckingham, UK) using artificial silicone feeding membranes [10].

Generation of primary cell cultures

On 28 June 2018, 10-week-old female G. m. morsitans with large white abdomens (typically indicative of pregnancy) were cold-anaesthetised in a Petri dish on ice. Flies had received their last feed of defibrinated horse blood 5 days earlier to minimise blood meal contamination during dissection. Using dissecting tweezers, each fly’s head was pinched off at the neck, and the headless body was transferred into a class II microbiological safety cabinet where it was surface-sterilised by immersion in either 70% ethanol for 1–2 min or 0.1% benzalkonium chloride for 1 min, followed by 70% ethanol for 1 min, and placed on sterile absorbent paper towel for 1 min to remove excess fluid. The body was then dissected aseptically in a 20-µl drop of sterile phosphate-buffered saline on a sterile glass slide using sterile watchmakers’ forceps. The penultimate abdominal segment was grasped, and the reproductive tissues were gently pulled out of the posterior end of the abdomen to avoid midgut rupture. The developing ovarioles, spermathecae, uterus and larva were freed from other connective tissues (Fig. 1), and the larva was transferred to Hanks balanced salt solution (HBSS) in a sterile bijou container. The developmental stage of each larva was recorded as instar stage L1, L2 or L3.

Reproductive tissues dissected out from the body of an adult female Glossina morsitans morsitans fly. The uterus was gently retracted to visualise the posterior end of the developing larva. Ov ovarioles, Sp spermatheca, FB fat body, Ut uterus, 1st instar L1 larva. Scale bar = 0.5 mm

Full size image

Within 2 h of harvest, each larva was individually macerated using sterile watchmakers’ forceps and the tissue pieces transferred to a flat-sided cell culture tube (Nunc, Thermo-Fisher, Loughborough, UK) with 2 ml complete culture medium. Membrane-like tissues of adult origin surrounding four L1 larvae and two fertilised eggs (isolated from the uterus) were collected and placed together in a separate culture tube with medium. Four complete culture media were used: L-15 (Leibovitz) supplemented with 10% tryptose phosphate broth (TPB) (L-15), L-15B [11] supplemented with 10% TPB and 0.1% bovine lipoprotein concentrate (L-15B), HBSS supplemented with 0.5% lactalbumin hydrolysate (H-Lac) and Schneider’s Drosophila medium (Schneider’s). All media were additionally supplemented with 20% foetal bovine serum, 2 mM L-glutamine, 100 units/ml penicillin and 100 µg/ml streptomycin. Medium components were supplied by Invitrogen (Thermo-Fisher, Loughborough, UK) or Sigma (Sigma-Aldrich, Gillingham, UK). All cultures were incubated sealed, in ambient air, in a dry incubator at 28 °C. Medium was changed weekly by removal and replacement of ¾ of the volume using freshly prepared complete medium, and cultures were examined weekly by inverted microscope for evidence of cell growth.

Development of the GMA/LULS61 cell line

When growing cells covered at least 50% of the flat surface of the culture tube, they were initially resuspended by gentle pipetting and allowed to reattach. Following regrowth to at least 75% confluence, subculture was carried out by adding 2.2 ml fresh complete medium, pipetting and transferring half of the resultant cell suspension to a new flat-sided tube. Later subcultures were made into T25 flasks by combining half of the cells from two flat-sided tubes to give a final volume of 5 ml. Subcultures from T25 flasks were subsequently made by addition of 5 ml fresh medium, resuspending the cells by scraping or pipetting and transferring 5 ml cell suspension to a new flask.

Cytocentrifuge smears of resuspended cells were periodically prepared using a Shandon Cytospin 4, air dried, fixed in methanol, stained with Giemsa and examined at × 1,000 magnification (oil immersion) using a transmission light microscope. Measurements of growing cells were carried out using a Zeiss Axiovert microscope with Zen Pro software (Carl Zeiss Ltd., Cambridge, UK). Supernatant medium was periodically screened for mycoplasma using at least two commercial kits as described previously [12]. Cells were cryopreserved with 10% dimethyl sulphoxide in vapour phase liquid nitrogen and resuscitated as described previously [13].

Metaphase chromosome spreads were prepared from GMA/LULS61 cells at passage 17 by a modification of a previously described method [13]. Briefly, a 67-day-old culture at passage 16 was resuspended by vigorous pipetting and divided between two daughter flasks. On day 3 after passage, the medium was changed, 2 ml of colcemid (10 µg/ml, Roche Diagnostics, Newhaven, UK) was added to the daughter flasks, and the cells were incubated overnight at 28 °C. On the next day, the medium was removed, and the cells were rinsed with PBS and incubated in 1 ml of 0.025% trypsin/0.01% EDTA (Invitrogen) for 5 min at 28 °C. Complete L-15 medium (3 ml) was added, the cells were harvested by scraping, centrifuged at 500 × g for 5 min, resuspended in 5 ml 0.7% sodium citrate and incubated for 35 min at 37 °C. The cells were centrifuged as before; the pellet was resuspended in 2.5 ml ice-cold acetic alcohol (3 parts methanol, 1 part glacial acetic acid) and held on ice for 5 min. This fixation step was repeated once, and then the cell pellet was resuspended in an equal volume of ice-cold acetic alcohol and deposited dropwise onto wet, ice-cold microscope slides from a height of 1 m. The slides were air-dried, stained in 3% Giemsa for 1 h and examined at × 300 magnification to locate countable metaphase chromosome spreads. The chromosomes were counted in 100 spreads.

Molecular characterisation

GMA/LULS61 cells were resuspended by pipetting or scraping and centrifuged at 200 × g for 5 min at room temperature. DNA was extracted from cell pellets using a DNeasy Blood and Tissue Kit (Qiagen, Hilden, Germany) following the manufacturer’s instructions for cultured cells. To confirm species origin, PCRs targeting a ~ 1500 bp fragment of the eukaryotic 18S rRNA gene and a ~ 700 bp fragment of the mitochondrial COI gene were carried out as described previously [12, 14, 15]. To screen for contaminating bacteria, a pan-bacterial PCR targeting a fragment of the bacterial 16S rRNA gene [16] was performed as described previously [12]. Positive PCR products were detected by agarose gel electrophoresis, purified using a PureLink PCR purification kit (Thermo-Fisher, Loughborough, UK) and Sanger sequenced in both directions (Source Bioscience, Nottingham, UK). The resultant sequences were compared to published sequences in GenBank using BLAST. Phylogenetic trees were generated using the neighbour-joining Tamura-Nei model with 1000 bootstraps.

Virus screening

GMA/LULS61 cells at passage 14 in a T25 flask were harvested by scraping, pelleted by centrifugation at 200 × g for 5 min, resuspended in 1 ml PBS, transferred to a 1.5 ml microfuge tube, centrifuged as before, and the cell pellet was overlain with 1.4 ml RNAlater^® (Sigma-Aldrich, Gillingham, UK). The cell pellet was then shipped from the Tick Cell Biobank to the Insect Pest Control Laboratory (IPCL) of the Joint FAO/IAEA Centre of Nuclear Techniques in Food and Agriculture, Seibersdorf, Austria, for subsequent processing. DNA and RNA were extracted using a TRIzol^™ Reagent kit (Invitrogen, Thermo-Fisher Scientific, Waltham, MA, USA), and RNA was converted to cDNA using a Superscript III kit (Invitrogen, Thermo-Fisher Scientific, Waltham, MA, USA), following the manufacturer’s instructions. PCR reactions were conducted using the Platinum II master mix (Invitrogen, Thermo-Fisher Scientific, Waltham, MA, USA), while qPCR reactions were conducted with the iQ SYBR Green Supermix (Biorad Laboratories, Hercules, CA, USA). Primers targeting a specific sequence of the salivary gland hypertrophy virus (SGHV) of Glossina pallipides [17], the RNA-dependent RNA polymerase (RdRp) gene of Glossina morsitans morsitans iflavirus (GmmIV), the RdRp gene of Glossina morsitans morsitans negevirus (GmmNegeV) [18] and PCR conditions are presented in Table 1. Primers targeting tsetse tubulin were used as a control for the nucleic acid extractions, and DNA from the oriental fruit fly Bactrocera dorsalis was used as a negative control. All reactions included a no-template control. Positive PCR products were detected by agarose gel electrophoresis, purified using a DNA Clean & Concentrator Kit (Zymoresearch, Freiburg im Breisgau, Germany) and Sanger sequenced in both directions (Eurofins Genomics, Ebersberg, Germany). The resultant sequences were compared to published sequences in GenBank using BLAST.

Infection of GMA/LULS61 cells with Wolbachia

GMA/LULS61 cells were seeded in flat-sided tubes in 2.2 ml complete L-15 medium and incubated at 28 °C for 7 days. A panel of seven strains of Wolbachia were grown in insect cell lines as summarised in Table 2. Culture supernatant containing cell-free Wolbachia of each test strain was passed through a 0.45-µm filter to remove any host cells, 0.3–0.5 ml of the filtrate was inoculated into GMA/LULS61 cells and the tubes were returned to 28 °C. Medium was changed weekly and cultures were examined by inverted microscope for signs of cytopathic effect (CPE). Giemsa-stained cytocentrifuge smears were prepared and examined for presence of Wolbachia-infected cells after 3 weeks and at intervals thereafter up to 13 weeks. DNA was extracted from cultures visually negative for intracellular bacteria as described in Sect. 2.4 and screened for presence of Wolbachia using a qPCR targeting a 99-bp fragment of the 16S rRNA gene as described previously [19].

Gift Noko, Econet Insurance’s Chief Insurance Officer

Econet Insurance, a leader in innovative short-term insurance solutions, has launched a new insurance package that covers mobile phone damage. 

The package, named Moovah Mobile Phone Insurance, was introduced in response to customer insights, according to Gift Noko, Econet Insurance’s Chief Insurance Officer.

“We are constantly seeking ways to meet our customers’ needs. This new package helps them protect their mobile phones against accidental damage, including cracks, shattered screens, and any impact damage,” Noko said at the launch event in Harare on Friday.

Mobile phones are essential tools for business, social, and educational purposes, storing sensitive information and cherished memories. However, accidental damage can significantly disrupt daily life, and Moovah Mobile Phone Insurance has set out to mitigate that disruption. 

Describing the insurance process, Noko said customers simply register their phones using the short code *901#. They are then required to get their device verified at the nearest Moovah Agent or Econet Shop throughout the country. 

He said all phones up to three years old are eligible for insurance coverage. “Customers just need to provide their phone model, IMEI number, and date of manufacture. Premium payments can be made conveniently via the EcoCash USD Wallet, and at any Moovah Agents or Econet Shops.

“In the event of a claim, customers can submit their device to any Moovah repair centre for assessment. Approved claims may result in device repair or replacement,” Noko explained.

The launch of the mobile phone damage insurance package coincides with a significant growth in the global device insurance market, which is expected to reach $193.5 billion by 2031, highlighting the increase in demand for such services.

EcoCash Holdings Chief Commercial Officer Gilbert Tsongorera said the group was committed to enhancing the mobile phone experience. 

“With our new insurance package, we are providing customers with the confidence and assurance they need to fully enjoy their mobile devices, knowing that they are protected against unexpected setbacks,” he said.

He said the insurance package was affordable, with premiums based on a phone’s value. “For instance, a phone worth $100 will have a monthly premium of $2.26,” he said.

In addition to mobile phone insurance, Moovah offers a range of insurance solutions, including Vehicle Cover, Home Comprehensive Cover, Legal Insurance, Crop and Livestock Cover, Plant and Equipment Cover, Electronic Equipment Cover, Liabilities Cover, Fidelity Guarantee Cover, and Theft or Fraud Cover.

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