West nile virus lineage 2 as a cause of zoonotic neurological disease in humans and horses in Southern Africa

West Nile virus (WNV) is widely distributed in South Africa, but since a few cases of neurological disease have been reported from this region, endemic lineage 2 strains were postulated to be of low virulence. Several cases of nonfatal encephalitis in humans as well as fatal cases in a foal, dog, and ostrich chicks have, however, been associated with lineage 2 WNV in South Africa. The pathogenesis of lineage 2 WNV strains was investigated using mouse neuroinvasive experiments, gene expression experiments, and genome sequence comparisons which indicated that lineage 2 strains that are highly pathogenic exist. To determine whether cases of WNV were being missed in South Africa, horses with fever and neurological disease were investigated. Several cases of WNV were identified, all associated with severe neurological disease, 85% of which had to be euthanized or died. All cases positive by RT-PCR were shown to belong to lineage 2 WNV by DNA sequencing and phylogenetic analysis. Two cases of occupational infection were investigated, including a case of zoonotic transmission to a veterinarian who performed an autopsy on one of the horses as well as a laboratory infection after a needle stick injury with a neuroinvasive lineage 2 strain. Both resulted in neurological disease. Cytokine expression was investigated in the second case to assess the immunopathogenesis of WNV. Collectively, these studies suggest that lineage 2 WNV may be significantly under estimated as a cause of neurological disease in South Africa.The authors thank the National Research Foundation, The Poliomyelitis Research foundation, and the National Health Laboratory Services for funding

Prevalence of hearing loss at primary health care clinics in South Africa

Background: Hearing loss prevalence data in South Africa is scarce, especially within primary health care settings. Objectives: To determine; (i) the prevalence of hearing disorders in patients ≥3 years of age attending two primary health care clinics, and (ii) the nature and characteristics of hearing disorders at these primary health care clinics. Method: A cross-sectional design was used at two primary health care clinics. Non-probability purposive sampling was used to screen participants at clinics for hearing loss with pure tone audiometry. A total of 1236 participants were screened (mean age 37.8 ±17.9 years). Diagnostic testing was available for confirmation of hearing loss on participants who failed the screening. Results: Hearing loss prevalence was 17.5% across both clinics. Most hearing losses were bilateral (70.0%) and were of a sensorineural nature (84.2%). Conclusion: Hearing loss prevalence was comparable at both primary health care clinics. Participants 40 years and older were at significantly higher risk for hearing loss. The current study is the first attempt to establish hearing loss prevalence for primary health care clinics in South Africa.Keywords: Hearing loss, primary health care clinics, South Africa

High prevalence of IgG antibodies to Ebola virus in the Efe pygmy population in the Watsa region, Democratic Republic of the Congo

Background: Factors related to the natural transmission of Ebola virus (EBOV) to humans are still not well defined. Results of previous sero-prevalence studies suggest that circulation of EBOV in human population is common in sub-Saharan Africa. The Efe pygmies living in Democratic Republic of the Congo are known to be exposed to potential risk factors of EBOV infection such as bush meat hunting, entry into caves, and contact with bats. We studied the pygmy population of Watsa region to determine seroprevalence to EBOV infection and possible risks factors. Method: Volunteer participants (N = 300) aged 10 years or above were interviewed about behavior that may constitute risk factors for transmission of EBOV, including exposures to rats, bats, monkeys and entry into caves. Samples of venous blood were collected and tested for IgG antibody against EBOV by enzyme-linked immunosorbent assay (ELISA). The chi(2)-test and Fisher's exact test were used for the comparison of proportions and the Student's t-test to compare means. The association between age group and anti-EBOV IgG prevalence was analysed by a nonparametric test for trend. Results: The prevalence of anti-EBOV IgG was 18.7 % overall and increased significantly with age (p = 0.023). No association was observed with exposure to risk factors (contacts with rats, bats, monkeys, or entry into caves). Conclusions: The seroprevalence of IgG antibody to EBOV in pygmies in Watsa region is among the highest ever reported, but it remains unclear which exposures might lead to this high infection rate calling for further ecological and behavioural studies

High seroconversion rate to Rift Valley fever virus in cattle and goats in far northern KwaZulu-Natal, South Africa, in the absence of reported outbreaks

Rift Valley fever (RVF) is a mosquito-transmitted viral disease that may cause large epidemics in domestic livestock and in humans. Although currently largely confined to Africa, it is of international concern due to its ability to spread and become established in areas where suitable mosquito vectors occur. Outbreaks occur sporadically, associated with conditions favourable for proliferation of mosquito populations, such as high rainfall and flooding, yet their location and timing remain difficult to predict. In other areas there is evidence that RVF virus is endemic and may circulate without causing outbreaks. However,the location and extent of such areas is poorly known, as is the transmission dynamics of the virus in those areas. In this paper, we report the existence of such an area of endemic RVF virus transmission on the tropical coastal plain of South Africa bordering Mozambique, where we found a high rate of exposure of domestic cattle and goats to the naturally circulating virus over a two-year period, with no outbreaks being reported.Research in such areas will help us to assess the potential for spread of the virus to other areas and also to better understand the behaviour of the virus during periods between epidemics

International survey of audiologists' attitudes toward telehealth

PURPOSE : A better understanding of the attitudes of audiologists toward teleaudiology and their willingness to use teleaudiology is required to progress the application of teleaudiology technologies and services into clinical practice. Audiologists around the world were surveyed on their attitudes toward teleaudiology and their willingness to use it. METHOD : An online survey was sent to audiologists through professional associations' mailing lists. The survey included questions on the use of computer and video-conferencing technologies, awareness and previous use of teleaudiology, and willingness to use teleaudiology. RESULTS : Responses were provided by 269 people from 28 different countries, representing a wide cross-section of experience, qualification, and work settings; 77.8% of respondents were women. Almost all respondents had used PC-based video-conferencing; most had used related technologies and reported positive attitudes toward using these. However, less than 25% had used teleaudiology. CONCLUSIONS : Despite positive attitudes toward telehealth and associated technology, the low number of audiologists who have used teleaudiology for services indicates limited clinical adoption.Portions of this work were presented at the Second International Meeting on Internet & Audiology, Snekkersten, Denmark (September 2015).http://aja.pubs.asha.org/Speech-Language Pathology and Audiolog

Development and analytical validation of a group-specific RT-qPCR assay for the detection of the Simbu serogroup orthobunyaviruses

The Simbu serogroup within the genus Orthobunyavirus belongs to the family Peribunyaviridae and comprises 32 recognised three-segmented negative-sense single-stranded RNA viruses, with a cosmopolitan distribution. This group of arthropod-borne viruses includes important pathogens of humans and domestic animals e.g. Oropouche orthobunyavirus and Schmallenberg virus. Sensitive and specific diagnostic tools are required for recognition and control of outbreaks. A novel TaqMan® RT-qPCR assay was developed, optimised and analytically validated for the broad detection of the Simbu serogroup orthobunyaviruses. A region in the S segment, which encodes the nucleocapsid protein, was used to design a group primer set and a pair of differently labelled TaqMan® minor groove binder probes to distinguish phylogenetic clade A and B of the serogroup. Efficiencies determined for seven members of the group were 99% for Akabane orthobunyavirus (AKAV), 96% for Simbu orthobunyavirus (SIMV), 96% for Shuni orthobunyavirus (SHUV), 97% for Sathuperi orthobunyavirus (SATV), 84% for Shamonda orthobunyavirus (SHAV), 93% for Ingwavuma virus (INGV, now classified as Manzanilla orthobunyavirus) and 110% for Sabo virus (SABOV, now classified as AKAV). The 95% limit of detection (TCID50/reaction) was 10-3.61 for AKAV, 10-2.38 for SIMV, 10-3.42 for SHUV, 10-3.32http://www.elsevier.com/locate/jviromet2020-09-01hj2019Veterinary Tropical Disease

Self-reported hearing loss and pure tone audiometry for screening in primary health care clinics

OBJECTIVE : To evaluate the performance of self-reported hearing loss alone and in combination with pure tone audiometry screening in primary health care clinics in South Africa. DESIGN : Nonprobability purposive sampling was used at 2 primary health care clinics. A total of 1084 participants (mean age 41.2 years; SD 15.5 years; range 16-97 years, 74.0% female) were screened using self-report and audiometry screening. Those failing audiometric screening and a sample of those who passed audiometric screening were also assessed by diagnostic pure time audiometry, to confirm or negate the finding of a hearing loss. RESULTS : Four hundred and thirty-six participants (40.2%) self-reported a hearing loss with no significant association with gender or race. One hundred and thirty-six participant (12.5%) self-reported hearing loss and failed audiometry screening (35 dB HL at 1, 2, and 4 kHz). Combining self-report with a second stage audiometry screening revealed a high test accuracy (81.0%) for hearing loss, being most accurate (86.1%) to identify high-frequency hearing loss. CONCLUSION : While self-report of hearing loss is an easy and time-efficient screening method to use at primary health care clinics, its accuracy may be limited when used in isolation and it may not be sufficiently sensitive to detect hearing loss. Combining a simple audiometry screening as a second-stage screen can significantly improve overall performance and efficiency of the screening protocol.The financial assistance of the National Research Foundation (NRF) toward this research is hereby acknowledged (Grant No. 87757).https://journals.sagepub.com/home/jpcam2019Speech-Language Pathology and Audiolog

Accuracy of remote hearing assessment in a rural community

BACKGROUND : This study determined the accuracy of pure tone air conduction (AC) thresholds obtained using a synchronous telemedicine approach without a sound booth in a rural South African community. The global need for increased hearing healthcare currently far exceeds the capacity for delivering these services, especially in developing countries. A tele-audiology approach using a portable diagnostic audiometer could provide the solution, enabling hearing assessments to be conducted remotely and without a sound booth. MATERIALS AND METHODS : Hearing thresholds in a sound booth and natural environment were obtained froman initial sample of 20 adults (age range, 19– 63 years; mean age, 50 – 13 years; 55%female), recruited from a rural agricultural community. A subgroup of 10 adults (20 ears) volunteered for the telemedicine threshold testing. AC thresholds (250–8,000 Hz) were determined and subsequently compared in these environments. Typical threshold variability was determined using test–retest correspondence as a reference for the threshold correspondence using a telemedicine mode. RESULTS : Test–retest threshold correspondence in the booth and natural environmentswas within – 5 dB in 96.7%and 97.5%of comparisons, respectively. No significant differences were obtained in AC hearing thresholds determined in the telemedicine configuration comparedwith those recorded in the gold standard booth environment. Threshold correspondence between the telemedicine compared with booth and natural environments were within – 5 dB in 82% and 85% of comparisons, respectively. CONCLUSIONS : The current study demonstrates the validity of using synchronous telemedicine for conducting hearing assessments in a remote rural agricultural community without a sound booth.http://online.liebertpub.com/TMJhb201

Orthobunyavirus antibodies among humans in selected parts of the Rift Valley and northeastern Kenya

Ngari, Bunyamwera, Ilesha, and Germiston viruses are among the mosquito-borne human pathogens in the Orthobunyavirus genus, family Bunyaviridae, associated with febrile illness. Although the four orthobunyaviruses have been isolated from mosquito and/or tick vectors sampled from different geographic regions in Kenya, little is known of human exposure in such areas. We conducted a serologic investigation to determine whether orthobunyaviruses commonly infect humans in Kenya. Orthobunyavirus-specific antibodies were detected by plaque reduction neutralization tests in 89 (25.8%) of 345 persons tested. Multivariable analysis revealed age and residence in northeastern Kenya as risk factors. Implementation of acute febrile illness surveillance in northeastern Kenya will help to detect such infections.Swedish International Development Coorporation Agency (SIDA) through the African Regional Postgraduate Program in Insect Science of ICIPE.http://online.liebertpub.com/VBZhb201