Simulation techniques in optometric education: Is a model eye for tonometry a valuable instruction tool?

PURPOSE: Simulation techniques are used in healthcare education to support the development of clinical skills. The aim of this study was to investigate the perceived value of a tonometry model eye (TME) when used in teaching and learning the clinical skill of Goldmann applanation tonometry (GAT) in optometric education in the UK. METHODS: A retrospective two-armed cross-sectional study was conducted to investigate the perceived value of using a model eye for teaching and learning GAT in optometric education. Focus group discussion (FGD) was employed to explore the views of academic experts experienced in teaching GAT using a TME. Semi-structured surveys were conducted to elicit the opinions of optometry students following GAT simulation training. Qualitative thematic analysis of the FGD and open-ended survey questions was undertaken. Quantitative data based on rated student responses was assessed using Chi-square analysis to examine differences between year-group responses. RESULTS: The TME was reported to be a useful experiential tool, facilitating a safe learning environment for students to develop the technical skills required to perform GAT before moving on to real-eye experiences. Whilst limitations of the model eye were noted, these did not diminish the value of the model eye as an instructional tool. Students reported improved confidence (86%) and would highly recommend (82%) the TME to other students. CONCLUSION: The model eye for tonometry was perceived by academic tutors and optometry students to be a valuable instruction tool as part of a scaffolded process for learning GAT. Irrespective of their learning stage, students reported a range of benefits from the model eye, such as being able to make mistakes, taking repeat measurements and getting used to the equipment, all whilst not having to worry about patient safety.

Medical Educators' Perceptions of Research Culture in a Faculty of Health Sciences: A South African Study.

Phenomenon: In South Africa, as with many other developing countries, a call has been made for institutions of higher learning to participate in more research and set the pace for societal transformation. At the Faculty of Health Sciences (FoHS), University of the Free State (UFS), numerous strategic efforts are focused on supporting and stimulating research. An essential prerequisite for the success of these vital efforts is to be aware of the research culture within the academic faculties. A peculiarity of medical colleges in South Africa is that medical faculties are in partnership with the government through the academic training hospitals; hence, staff appointment occurs through a joint structure with both the provincial Department of Health and the National Health Laboratory Services. So far, no known study has investigated research culture in this context (joint staff appointment). Approach: This study included elements of case study evaluation and improvement-oriented evaluation. We distributed to 242 educators a structured questionnaire to obtain perceptions of aspects of research, research processes, and existing research culture in the FoHS, UFS. Suggestions on how to improve the research culture also were obtained. The structured questionnaire was self-administered, consisted of closed and open-ended questions grouped into five main sections, and was distributed electronically and manually (hard copy) to participants. Findings: One-hundred-eleven questionnaires were returned (46% response rate). Motivation to do research varied by school and included career advancement (77%, School of Allied Health Professions); change the situation (80%, Academic support); develop individual skillset (67%, School of Nursing) and improve patient care (62%, School of Medicine). Perceived factors affecting research culture included limited funding and allocated time for research, minimal leadership support for research, and absence of research-related support structures as well as minimal teamwork/collaboration. Frustration was the most reported (negative) emotion (25%). Participants suggested that encouraging teamwork among staff, reducing workload to allow time for research, establishing a mentorship program, providing training on deficient skills, and more support from leadership would improve research culture. Insights: This present study reveals some of the factors that impact negatively on research, research culture, and productivity in a medical college in a resource-limited setting. While the benefits of joint staff appointment cannot be overemphasized, our findings highlight that the complex interplay between employers/stakeholders result in poorly executed joint appointment scheme/models (i.e., competitive approach) and creates numerous challenges that negatively impact research productivity and research culture. Recommendations suggested herein can be implemented by the FoHS and other medical colleges in similar contexts to improve research productivity and foster an enabling research culture.

Molecular survey of feline immunodeficiency virus (FIV) infection in Namibian cats.

Feline Immunodeficiency Virus (FIV) is one of the most important infectious diseases of cats, with potential implications in wildlife conservation. Unfortunately, FIV screening and surveillance in domestic cats remains limited in several African countries, including Namibia. In this study, 279 blood samples from domestic cats in Namibia were analyzed for FIV diagnosis by PCR. The cats represented various regions and were cared for by people largely from rural areas with limited financial means. Only 1.43 % of the samples tested positive, unexpectedly low given their outdoor lifestyles. The infected cats, primarily adult and unsterilized, showed no typical FIV symptoms, suggesting subclinical infections. Genetic analysis of the detected strains indicated a unique FIV strain cluster in Namibia, although with a certain within-country variability, in the absence of consistent geographical clustering. The present study represents the first detection and genetic characterization of FIV in the Namibian domestic cat population. Although the infection frequency was low, also in the rural free-roaming population, the features of the enrolled population could have biased the estimation, suggesting the need for more extensive surveys involving diseased and older cats as well. Additionally, because of the long-lasting subclinical nature of the infection, frequent monitoring activities should be performed that allow prompt isolation of infected animals and the implementation of appropriate control measures if necessary.

High detection frequency and genetic diversity of porcine circovirus 3 (PCV-3) in Namibian backyard farms and warthogs.

Since its first identification in 2015, porcine circovirus 3 (PCV-3) has been reported worldwide with a high frequency and in the presence of several clinical conditions, although its impact on pig health and productivity is still debated. Data on the presence of PCV-3 in Africa are, however, limited. A previous study performed on commercial pigs in Namibia failed to identify the pathogen. In the present study, the viral circulation in backyard farms, characterised by lower biosecurity measures and frequent animal exchange between farms, was assessed. The susceptibility of warthogs to PCV-3 infection and their potential epidemiological role were also evaluated. Tonsils from 77 pigs from backyard piggeries and 55 warthogs were collected in different regions of Namibia and tested by PCR. Positive samples were sequenced and compared to PCV-3 strains circulating globally. Forty-two out of 77 pigs (54.54 %) and 12 out of 55 warthogs (21.82 %) tested positive, demonstrating the presence of PCV-3 in the country and suggesting that the high biosecurity measures implemented in the commercial farms that previously tested negative for PCV-3 probably prevented viral introduction. The partial ORF2 gene was successfully sequenced in samples from 27 pigs and 6 warthogs. Genetically, the identified strains were part of 3 distinct groups which included both backyard pigs and warthogs from different regions of Namibia. There is also evidence for the occurrence of multiple introduction events most likely from Asian countries, either directly into Namibia or through other African countries. Considering the strict Namibian regulations on live animal importation, understanding the source of viral introduction is challenging, although semen importation or the habit of feeding backyard pigs with human food waste might have played a role. Pig exchanges between farms for breeding purposes or wildlife movements could also have been involved in PCV-3 dispersal within Namibia. Despite the significant advances in the field, further studies should be undertaken to properly understand PCV-3 epidemiology in Namibia and its impact on pig productivity and wildlife health.

Unveiling the molecular epidemiology of canine distemper virus in Namibia: An expected pathogen showing an unexpected origin.

Objective: Canine distemper virus (CDV) is a highly infectious virus that represents a threat for domestic dogs and several wild species. Despite recognized in several African countries, current knowledge of its molecular epidemiology is scarce and poorly updated. Design: Twenty-two hemagglutinin sequences, obtained from symptomatic Namibian dogs from 2020 to 2023, were analysed through phylogenetic and phylodynamic analysis to characterize the local CDV epidemiology and contextualize it in the international scenario. Results: Two unrelated clades were identified, including strains sampled in different Namibian towns, in the absence of a strong geographical clustering. The ancestors of the two clades were estimated to have originated from South America, likely Brazil, and South Africa, approximately in 2000 and 2006, respectively. While the introduction from South Africa was predictable, the introduction from Brazil was unexpected. The mediation of other African countries, particularly Angola, appears to be the most likely importation pathway. Conclusions: The occurrence of multiple introduction events, likely originating from cross-border illegal animal trade between African countries, and the absence of any geographical clustering within Namibian regions, suggest a need for further investigation into its spreading pattern, as well as improved biosecurity measures to limit foreign viral introduction into the country.

Evidence indicating transmission of porcine parvovirus 1 between warthogs and domestic pigs in Namibia.

Thirty swine samples collected from different regions of Namibia between 2019 and 2020 were screened for the presence of porcine parvovirus 1 (PPV1) by PCR. Eleven samples (37%) were positive. Phylogenetic analysis of a partial sequence of the structural protein gene (VP2) identified two distinct clusters, one which contained sequences that were highly similar to PPV1 previously identified in warthogs in Namibia. These results indicate possible PPV1 transmission between warthogs and domestic pigs and highlight the importance of wildlife as sources of pathogens.

Molecular epidemiology of Canine circovirus in domestic dogs and wildlife in Namibia, Africa.

Canine circovirus (CanineCV) is a DNA virus affecting domestic dogs and other wild carnivore species. Despite the potential implications for dogs' health and wildlife conservation, data on CanineCV presence, epidemiology and genetic features from Africa is still poor. In the present study, biological specimens collected between 2020 and 2022 from a total of 32 jackals and 575 domestic dogs were tested for the presence of CanineCV DNA to evaluate its frequency. Furthermore, sequencing was conducted on positive samples to characterize the strains and compare them with publicly available sequences through phylogenetic analysis. A high CanineCV prevalence was observed both in jackals (43.75%; 95 CI: 28.17% - 60.67%) and domestic dogs (27.13%; 95 CI: 23.66% - 30.91%). All aside from one Namibian strain formed an independent clade, suggestive of extremely rare introduction events, followed by local persistence, circulation, and evolution. Remarkably, different recombination events were observed involving strains from both jackals and domestic dogs, which testify to the likely strain exchange between these populations. Distinctive amino acid residues were also observed in jackals. The limitations of the considered host populations however prevent a definitive conclusion on host adaptation, biological, and clinical features. Further studies should be performed to expand our current knowledge of the CanineCV disease scenario in Namibia, other African regions, and associated host species in Africa.

Investigation and sequence analysis of psittacine beak and feather disease virus and avian polyomavirus from companion birds in Windhoek, Namibia.

The commercial farming and trading of parrots and ornamental birds as companion animals are important economic activities in many countries. Some of the bird species farmed/traded are captured from the wild or are closely related to wild birds and therefore represent a risk of pathogen exchange/introduction. Beak and feather disease virus (BFDV) and avian poliomavirus (APV) are among the viruses with the biggest impact on companion bird populations and have been detected in different hosts worldwide. Despite their relevance for both domesticated and wild birds, our knowledge of BFDV and APV epidemiology remains limited in several African countries. In the present study, 143 cloacal swabs were collected from companion birds in Windhoek, Namibia, and tested by polymerase chain reaction for BFDV and APV. Of the samples tested, 35/143 (24.48%) tested positive for BFDV; 11/143 (7.69%) were positive for APV; and 6/143 (4.2%) tested positive for both pathogens. Positive amplicons, consisting of segments of the ORF1 and VP1 genes, were sequenced and compared with sequences from viruses identified in other countries. Four Namibian-only clades of BFDV were identified, loosely related to foreign strains, which suggest the occurrence of multiple introduction events in the past, potentially from South Africa, followed by local, independent evolution. In contrast, the Namibian APV sequences were identical to each other and form a single clade. In both instances, no correlation was observed between the sampling host and the viral phylogeny, suggesting the absence of host-specific adaptation and a remarkable, unconstrained viral circulation within Namibian borders. Therefore, while regulations and control measures developed against foreign strain introduction have proven to be effective over time, the spread of BFDV and APV within Namibia's borders appears undeterred. Additional resources should be dedicated to limit strain circulation in commercial farming facilities, markets and small-scale traders.

First detection and molecular characterization of porcine reproductive and respiratory syndrome virus in Namibia, Africa.

Introduction: The swine sector in Africa plays an important role in local economies, contributing to poverty alleviation and community subsistence. In addition, intensive farming is progressively becoming more important in the region. Therefore, any disease affecting swine populations can have detrimental effects on local communities. Porcine Reproductive and Respiratory Syndrome (PRRS) is among the most important infectious diseases affecting swine worldwide, but information on its epidemiology in Africa is extremely limited. Material and methods: In the present study, 147 healthy butchered pigs, originating from 15 Namibian intensive and rural farms were tested by RT-PCR and the ORF7 genes of positive samples were sequenced for further genetic characterization and phylogenetic analysis. Additionally, 55 warthogs were also evaluated using the same approach. Results: Overall, 7 out of 147 pigs (4.76%) tested positive, all originating from 3 rural farms (with a within-herd detection frequency higher than 14%) characterized by strong epidemiological links. All industrial pig and warthog samples were negative. Sequence analysis revealed that all strains belonged to the Betaarterivirus suid1 species, previously known as PRRSV type I, and were likely imported from Europe at least 6 years ago, evolving independently thereafter. When and how the first introduction occurred could not be determined due to the absence of other African sequences for comparison. Discussion: The present work provides the first detection and characterization of PRRSV molecular epidemiology in Namibia. Based on the present findings, the presence of the PPRSV appears marginal and limited to backyard farms. While biosecurity measures applied in industrial farms appear to be effective in preventing viral introduction, PRRSV circulation in rural settings still represents a potential threat, and considering the socio-economical implication of livestock diseases decreasing animal performances in rural areas, active monitoring should be encouraged to promptly act against emerging menaces and guarantee the welfare of local pig populations.

Development and validation of an RT-qPCR for detection and quantitation of emerging epizootic hemorrhagic disease virus serotype 8 RNA from field samples.

Epizootic hemorrhagic disease virus (EHDV) is a Culicoides-transmitted virus circulating in multiple serotypes. It has become a concern in the European Union as a novel strain of the serotype 8 (EHDV-8) of clear Northern African origin, has been recently discovered in symptomatic cattle in Italy (islands of Sardinia and Sicily), Spain, and Portugal. Current molecular typing methods targeting the S2 nucleotide sequences -coding for the outermost protein of the virion VP2- are not able to detect the novel emerging EHDV-8 strain as they enrolled the S2 sequence of the unique EHDV-8 reference strain isolated in Australia in 1982. Thus, in this study, we developed and validated a novel typing assay for the detection and quantitation of the novel EHDV-8 RNA from field samples, including blood of ruminants and insects. This molecular tool will certainly support EHDV-8 surveillance and control.

Is Penguin Circovirus Circulating Only in the Antarctic Circle? Lack of Viral Detection in Namibia.

The known host range of circoviruses is continuously expanding because of more intensive diagnostic activities and advanced sequencing tools. Recently, a new circovirus (penguin circovirus (PenCV)) was identified in the guano and cloacal samples collected from Adélie penguins (Pygoscelis adeliae) and chinstrap penguins (Pygoscelis antarcticus) in Antarctica. Although the virus was detected in several asymptomatic subjects, a potential association with feather disease was speculated. To investigate the occurrence and implications of PenCV in other penguin species located outside of Antarctica, a broad survey was undertaken in African penguins (Spheniscus demersus) on two islands off the southern Namibian coast. For this purpose, specific molecular biology assays were developed and validated. None of the 151 blood samples tested positive for PenCV. Several reasons could explain the lack of PenCV positive samples. African penguins and Pygoscelis species are separated by approximately 6000 km, so there is almost no opportunity for transmission. Similarly, host susceptibility to PenCV might be penguin genus-specific. Overall, the present study found no evidence of PenCV in African penguin colonies in Namibia. Further dedicated studies are required to assess the relevance of PenCV among different penguin species.

Highly pathogenic avian influenza H5N1 virus outbreak among Cape cormorants (Phalacrocorax capensis) in Namibia, 2022.

In January 2022, significant mortality was observed among Cape cormorants (Phalacrocorax capensis) on the west coast of Namibia. Samples collected were shown to be positive for H5N1 avian influenza by multiplex RT-qPCR. Full genome analysis and phylogenetic analysis identified the viruses as belonging to clade 2.3.4.4b and that it clustered with similar viruses identified in Lesotho and Botswana in 2021. This is the first genomic characterization of H5N1 viruses in Namibia and has important implications for poultry disease management and wildlife conservation in the region.

Phylodynamic and phylogeographic reconstruction of beak and feather disease virus epidemiology and its implications for the international exotic bird trade.

Beak and feather disease virus (BFDV) infects domestic and wild psittacine species and is able to cause progressive beak, claw and feather malformation and necrosis. In addition to having an impact on the health and welfare of domesticated birds, BFDV represents a significant threat to wild endangered species. Understanding the epidemiology, dynamics, viral migration rate, interaction between wild and domestic animals and the effect of implemented control strategies is fundamental in controlling the spread of the disease. With this in mind, a phylodynamic and phylogeographic analysis has been performed on a database of more than 400 replication-associated protein (Rep) gene (ORF1) sequences downloaded from Genbank including some recently generated sequences from fifteen samples collected in Namibia. The results allowed us to reconstruct the variation of viral population size and demonstrated the effect of enforced international bans on these dynamics. A good correlation was found between viral migration rate and the intensity of animal trade between regions over time. A dominant flux of viral strains was observed from wild to domestic populations, highlighting the directionality of viral transmission and the risk associated with the capturing and trade of wild birds. Nevertheless, the flow of viruses from domestic to wild species was not negligible and should be considered as a threat to biodiversity. Therefore, considering the strong relationship demonstrated in this study between animal trade and BFDV viral fluxes more effort should be made to prevent contact opportunities between wild and domestic populations from different countries in order to control disease spread.

Molecular epidemiology of canine parvovirus in Namibia: Introduction pathways and local persistence.

Canine parvovirus is a member of the Carnivore protoparvovirus 1 species that, after a relatively recent origin, has reached a worldwide distribution. Like other ssDNA viruses, it is featured by a remarkable evolutionary rate and thus genetic variability. CPV-2 is responsible for a severe systemic infection affecting especially domestic dogs. However, other carnivores, including wild species, are susceptible and thus represents a menace to wildlife conservation too. Despite the relevance of the topic, molecular epidemiology data are scarce and outdated in certain areas of the world, like Africa and, in particular, Namibia. The present study investigates the occurrence and genetic features of CPV in Namibian domestic dogs and jackals. The VP2 of detected strains was characterized and analyzed to assess the viral circulation and link among host species, Namibian districts and foreign countries. With the only exception of one New-CPV-2a, all the detected strains belonged to the CPV-2c antigenic variant and were closely related to strains of Asian origin. Nevertheless, a dedicated phylogeographic analysis revealed that the introduction was more likely mediated by other African countries, highlighting the challenge of controlling illegal animal imports across land borders. Similarly, the absence of any geographical clustering within Namibia testify a substantially unconstrained viral circulation among districts. The absence/incomplete vaccination status reported by the animal owners could have significantly contributed to the infection's success after its introduction. Finally, infection of a wild jackal was also proven. Although the limited wild animals' sample size prevents any definitive conclusion, the identity of the sequences from the jackal and the ones originating from the domestic dogs suggests a potential inter-species transmission. The epidemiological and clinical implications in wild specie remain obscure.

Molecular characterization of avipoxviruses circulating in Windhoek district, Namibia 2021.

Samples from eleven birds (chicken, dove and peacock) with symptoms of fowlpox, caused by the avipoxvirus (APV), were collected in seven different areas of the Windhoek district, Namibia between April and October 2021. A fragment of the 4b core protein and the DNA polymerase gene of APV were amplified by PCR from the DNA of the samples and sequenced. Phylogenetic analysis revealed that the viruses present in the chickens all belonged to clade A1 while the viruses in the doves and peacock were from subclade A3.1. This is the first report of subclade A3.1 avipoxvirus in peacock. In addition, all of the samples obtained from chickens were shown by PCR to be positive for the integration of reticuloendotheliosis virus while those from the doves and peacocks were negative. This study is the first characterization of avipoxvirus in Namibia and provides additional information on the presence of avipoxvirus in southern Africa.

Molecular Detection and Genetic Characterization of Porcine Circovirus 2 (PCV-2) in Black-Backed Jackal (Lupulella mesomelas) in Namibia.

Members of the genus Circovirus have been identified in several host species. While initially considered host-specific, there is growing evidence of their presence in unexpected hosts. Porcine circovirus 2 (PCV-2) is no exception, having been reported in animals belonging to different orders, including carnivores. Recently, PCV-2 was detected in domestic pigs, warthogs and antelopes in Namibia. Considering the potential contact between these populations and wild carnivores, the presence of PCV-2 was investigated in 32 black-backed jackals (Lupulella mesomelas) shot between February and July 2021 as part of predator control operations in Namibia. Two lung lymph nodes tested positive for PCV-2 by PCR, confirming the broader-than-expected PCV-2 host tropism and the susceptibility of canids. Sequence analysis demonstrated a close association between the PCV-2s identified in the jackals and PCV-2b strains collected from South African domestic pigs. Although several hypotheses regarding the source of the jackal's infection are proposed, further studies should be performed to properly assess how PCV-2 is acquired and maintained in the wild and its potential impact on wild and domestic species.

SARS-CoV-2 in Namibian Dogs.

The pandemic of coronavirus disease 19 (COVID-19) has focused the attention of researchers, and especially public opinion, on the role of the human-animal-environment interface in disease emergence. At the beginning of the COVID-19 pandemic, media reports regarding the role of pets in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused significant concern and social anxiety. Although nowadays proven negligible in developed countries, essentially no studies have been performed in low-income African areas where companion animals are often raised differently from high income countries, and the contact patterns occurring in these scenarios could affect the epidemiological scenario. An extensive molecular biology survey was performed from March 2022 to September 2022 on Namibian dogs residing in urban and rural areas, showing a low but not negligible SARS-CoV-2 prevalence (1%; 95CI: 0.33-2.32%) of 5 out of 500. In only one instance (i.e., a 4-year-old female Labrador) was there a clear association that could be established between the infections of the owner and animal. In all other cases, no evidence of human infection could be obtained and no episodes of COVID-19 were reported by the owners. Although no consistent evidence of pet-to-pet transmission was proven in the present study, a cautionary principle suggests intensive and dedicated investigation into companion animal populations, especially when animal contact is frequent and a particularly susceptible population is present.

The Oryx Antelope (Oryx gazella): An Unexpected Host for Porcine Circovirus-2 (PCV-2).

For several years after its discovery, Porcine circovirus 2 (PCV-2) represented a major threat to the swine industry through economic losses due to the associated clinical syndromes, decreased production performances in both symptomatic and asymptomatic animals and disease management costs. Widespread vaccination administration has largely reduced the impact of this infection and represents the most effective control measure. The efficacy of vaccination is threatened by the emergence of novel (or uncommon) PCV-2 genotypes. In addition to domestic pigs, PCV-2 has been detected in several other species, a fact which could have an impact on new variant emergence and maintenance. Considering this, the present study assessed the distribution of the minor PCV-2c genotype in non-Suidae ungulates in Namibia. Red hartebeests (Alcelaphus buselaphus caama) (n = 44), kudus (Tragelaphus strepsiceros) (n = 10) and oryxes (Oryx gazella) (n = 54), whose mediastinal lymph nodes were sampled after slaughtering during the period 2019-2021, were included in the study. Two oryxes (3.7%; 95% CI = 0.45-12.75%) were PCV-2-positive by PCR. Complete genome sequence was obtained for the two samples identifying them as PCV-2c genotype. The sequences were identical and shared a high percentage of identity (~99.9%) with those recently obtained from warthogs living in the same area. The present study confirms the presence of the PCV-2c genotype (previously considered extinct) in Namibian wild animal populations and demonstrates greater than expected PCV-2 host plasticity. Because of the role these niches can have in the maintenance and evolution of minor PCV-2 genotypes, more extensive and dedicated studies should be performed to prepare authorities to promptly react to potential emerging threats from these viruses.