Human cases of Sindbis fever in South Africa, 2006-2010.

Sindbis virus (SINV), the prototype positive-sense RNA alphavirus, causes febrile arthritis and is present throughout Afro-Eurasia. Little is known of the epidemiology of Sindbis fever due to insufficient surveillance in most endemic countries. The epidemiological features of Sindbis fever in humans in South Africa are described here based on a retrospective study of suspected arbovirus cases submitted for laboratory investigation from 2006 to 2010. Cases were detected annually mostly during the late summer/early autumn months and an increase in cases was noted for 2010, coinciding with an outbreak of Rift Valley fever. Cases were reported most often from the central plateau of South Africa and involved mostly males. No severe or fatal cases were reported and cases were associated with febrile arthralgia as commonly reported for SINV infection. Further surveillance is required to reveal the true extent of the morbidity of Sindbis fever in South Africa.

Dog rabies in southern Africa: regional surveillance and phylogeographical analyses are an important component of control and elimination strategies.

In the resource-poor settings where dog rabies remains endemic, the demonstration of a need to divert scarce funds towards exhaustive surveillance activities is no easy task. Here, we investigate a recent case of human rabies in South Africa, which generated much public interest and wide media coverage. One of the factors contributing to the hype was an uncertainty about the geographical origin of the infection. This provided an opportunity to highlight the importance of increased regional surveillance and basic phylogeographical analyses in rabies control and elimination strategies. Our aim was to elucidate the origins of the virus responsible for this case, as the patient was from a well-vaccinated area that had been free from dog rabies cases for many years. The phylogeographical techniques that we applied would also be most useful in any end-stage infectious disease control programme, specifically in verifying the source of novel cases in order to rapidly respond towards maintaining the integrity of disease-free areas. The most likely origin of our case was shown to be from outside the disease-free area and indeed from outside the country of South Africa. We conclude that phylogeographical techniques can provide rapid and statistically rigorous answers to epidemiologically pertinent questions that impact on disease control strategies and resource allocation, but this will require coordinated regional surveillance practices.

First report of an imported case of haemorrhagic fever with renal syndrome in South Africa.

Haemorrhagic fever with renal syndrome (HFRS) is caused by hantavirus infection. Hantaviruses are not endemic to South Africa, and we report the first detection of an imported case of HFRS in the country. The case involved a traveller from Croatia who presented to a Johannesburg hospital with an acute febrile illness with renal dysfunction. The patient reported visiting rurally located horse stables in Croatia before falling ill, and that a worker in the stables with similar illness was diagnosed with HFRS. Given the exposure history and clinical findings of the case, a clinical diagnosis of HFRS was made and confirmed by laboratory testing.

Predictors of engagement with remote sensing technologies for symptom measurement in Major Depressive Disorder.

BACKGROUND: Remote sensing for the measurement and management of long-term conditions such as Major Depressive Disorder (MDD) is becoming more prevalent. User-engagement is essential to yield any benefits. We tested three hypotheses examining associations between clinical characteristics, perceptions of remote sensing, and objective user engagement metrics. METHODS: The Remote Assessment of Disease and Relapse - Major Depressive Disorder (RADAR-MDD) study is a multicentre longitudinal observational cohort study in people with recurrent MDD. Participants wore a FitBit and completed app-based assessments every two weeks for a median of 18 months. Multivariable random effects regression models pooling data across timepoints were used to examine associations between variables. RESULTS: A total of 547 participants (87.8% of the total sample) were included in the current analysis. Higher levels of anxiety were associated with lower levels of perceived technology ease of use; increased functional disability was associated with small differences in perceptions of technology usefulness and usability. Participants who reported higher system ease of use, usefulness, and acceptability subsequently completed more app-based questionnaires and tended to wear their FitBit activity tracker for longer. All effect sizes were small and unlikely to be of practical significance. LIMITATIONS: Symptoms of depression, anxiety, functional disability, and perceptions of system usability are measured at the same time. These therefore represent cross-sectional associations rather than predictions of future perceptions. CONCLUSIONS: These findings suggest that perceived usability and actual use of remote measurement technologies in people with MDD are robust across differences in severity of depression, anxiety, and functional impairment.

A case study of rabies diagnosis from formalin-fixed brain material.

Rabies is caused by several Lyssavirus species, a group of negative sense RNA viruses. Although rabies is preventable, it is often neglected particularly in developing countries in the face of many competing public and veterinary health priorities. Epidemiological information based on laboratory-based surveillance data is critical to adequately strategise control and prevention plans. In this regard the fluorescent antibody test for rabies virus antigen in brain tissues is still considered the basic requirement for laboratory confirmation of animal cases. Occasionally brain tissues from suspected rabid animals are still submitted in formalin, although this has been discouraged for a number of years. Immunohistochemical testing or a modified fluorescent antibody technique can be performed on such samples. However, this method is cumbersome and cannot distinguish between different Lyssavirus species. Owing to RNA degradation in formalin-fixed tissues, conventional RT-PCR methodologies have also been proven to be unreliable. This report is concerned with a rabies case in a domestic dog from an area in South Africa where rabies is not common. Typing of the virus involved was therefore important, but the only available sample was submitted as a formalin-fixed specimen. A real-time RT-PCR method was therefore applied and it was possible to confirm rabies and obtain phylogenetic information that indicated a close relationship between this virus and the canid rabies virus variants from another province (KwaZulu-Natal) in South Africa.

Epidemiology of human rabies in South Africa, 2008 - 2018.

BACKGROUND: Human rabies cases continue to be reported annually in South Africa (SA). Previous investigations have shown the association between the occurrence of human rabies cases and dog rabies cases in the country. OBJECTIVES: To describe the epidemiology of laboratory-confirmed human rabies cases in SA for the period 2008 - 2018. METHODS: A retrospective document review of laboratory-confirmed human rabies cases for the period 2008 - 2018 was performed using a case register and related documentation available from the National Institute for Communicable Diseases. RESULTS: A total of 105 human rabies cases were laboratory confirmed from 2008 to 2018, with cases reported from all the provinces of SA except the Western Cape. Children and adolescents were most affected by the disease during the study period. In almost half of the cases, medical intervention was not sought after exposure. When victims did seek healthcare, deviations from post-exposure prophylaxis protocols were reported in some cases. CONCLUSIONS: The epidemiological trends of human rabies cases reported in SA for the period 2008 - 2018 remained largely the same as in previous reports. Dog-mediated rabies remains the main source of human rabies in SA.

Development and evaluation of a real-time reverse transcription-loop-mediated isothermal amplification assay for rapid detection of Rift Valley fever virus in clinical specimens.

This paper reports on the development and validation of a real-time reverse transcription-loop-mediated isothermal amplification assay (RT-LAMP) targeting the genomic large RNA segment of Rift Valley fever virus (RVFV). The set of six designed RT-LAMP primers identified strains of RVFV isolated in geographically distinct areas over a period of 50 years; there was no cross-reactivity with other genetically related and unrelated arboviruses. When testing serial sera and plasma from sheep experimentally infected with wild-type RVFV, there was 100% agreement between results of the RT-LAMP, a TaqMan-based real-time PCR, and virus isolation. Similarly, the assay had very high levels of diagnostic sensitivity and specificity when testing various clinical specimens from humans and animals naturally infected with the virus during recent outbreaks of the disease in Africa. The detection of specific viral genome targets in positive clinical specimens was achieved in less than 30 min. As a highly accurate, rapid, and very simple nucleic acid detection format, the RT-LAMP has the potential to be used in less-well-equipped laboratories in Africa and as a portable device during RVF outbreaks in remote areas, and it can be a valuable tool for the differential diagnosis of viral hemorrhagic fevers.

Atypical presentation of Crimean-Congo haemorrhagic fever: Lessons learned.

An atypical case of Crimean-Congo haemorrhagic fever is presented. The diagnosis of the case in the presence of several comorbidities was complicated and illustrates the importance of maintaining a high index of suspicion for viral haemorrhagic fever in cases presenting with multisystem disease and an epidemiological history that could present opportunities for exposure to a haemorrhagic fever virus.

Spotted fever rickettsiosis in South Africa: Evaluation of laboratory diagnostic capacity and inter-laboratory comparison of serological testing.

BACKGROUND: Spotted fever rickettsiosis, also known as tick bite fever (TBF), is a common infectious disease in South Africa (SA). Although the diagnosis of TBF is often based on clinical grounds only, laboratory testing is important to confirm the diagnosis and can contribute to case management in the light of a myriad of differential diagnoses, and in complicated cases. OBJECTIVES: To report on the availability and scope of laboratory tests for investigating suspected cases of TBF in SA, and the outcome of an inter-laboratory comparison (ILC) conducted for serological tests. METHODS: A self-administered questionnaire was circulated to major pathology laboratories in SA to determine what TBF tests they offered for TBF investigation. In addition, a clinical panel was provided to willing laboratories in order to perform an ILC of the serological tests. RESULTS: Serological tests for TBF were available from five laboratories serving both the private and state medical sectors in SA. There was no standardised testing platform or result interpretation across the different laboratories. Polymerase chain reaction (PCR) tests were less frequently available, and not available to state-operated facilities. The outcome of the ILC indicated varied performance and interpretation of serological results for TBF. CONCLUSIONS: Laboratory investigation for TBF is routinely and widely available in SA. Both serological and PCR-based methods were varied, and the lack of standardisation and interpretation of tests needs to be addressed to improve the overall quality of TBF diagnosis in SA. The utility of ILC to identify problem areas in serological testing for TBF is highlighted, and laboratories in SA are encouraged to use it to improve the quality of testing.

Emotional outcomes in clinically isolated syndrome and early phase multiple sclerosis: a systematic review and meta-analysis.

OBJECTIVE: To study depression, anxiety, suicide risk, and emotional health-related quality of life (HRQoL) in people with clinically isolated syndrome (CIS) and in early phase multiple sclerosis (MS). METHODS: A systematic literature review was conducted with inclusion criteria of observational studies on outcomes of depression, anxiety, suicide risk, and emotional HRQoL in CIS and within five years since diagnosis of MS. Studies were screened using the Preferred Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines, and study quality was determined for included studies. Meta-analysis and meta-regression were performed if applicable. RESULTS: Fifty-one studies were included in the systematic review. In early phase MS, meta-analyses of the Hospital Anxiety Depression Scale (HADS) indicated prevalence levels of 17% (95% confidence interval (CI): 9 to 25%; p < .001) for depressive and 35% (95% CI: 28 to 41%; p < .001) for anxiety symptoms. Meta-regression analyses revealed an increase in mean HADS-D and HADS-A associated with larger sample size, and higher HADS-D mean with increased study quality. Similar depressive and anxiety symptoms were observed in CIS, and increased suicide risk and low emotional HRQoL was associated with depressive symptoms in early phase MS. The methodological quality of the studies was considered fair. CONCLUSIONS: Findings suggest that mild-to-moderate symptoms of depression and anxiety might be prevalent in CIS and in early phase MS. Future research on both clinical populations are needed, especially longitudinal monitoring of emotional outcomes.

[The pig--an experimental model for transplantation of isolated islets pancreatic islets]. / Osípaná--experimentálny model pre transplantáciu izolovaných ostrovcekov pankreasu.

The authors present results of autotransplantation of the islets of Langerhans of the pancreas in pigs and miniature pigs ("Troll"). Diabetes was induced by total pancreatomy. From the removed pancreas the islets of Langerhans were separated by the method of intraductal perfusion with collagenase and implanted into the spleen or liver via the portal vein. The mortality on operation in pigs was 33%, in miniature pigs 20%. In domestic pigs normal blood sugar levels were achieved in 25% after implantation of the islets of Langerhans into the liver (in 2 of 8 animals) and in 50% after implantation into the spleen (in 4 of 8 animals). In miniature pigs autotransplantation of the islets of Langerhans was equally successful when transplanted into the liver or the spleen -50%. The 50% success of autotransplantations justifies the use of pigs as a model for further investigations of allo- or xenotransplantations of the islets of Langerhans.

Management of rabies

Rabies is endemic in South Africa and human rabies cases continue to be reported annually. Most human cases in South Africa are dog-transmitted. Whilst efforts are underway to control and eventually eliminate dog rabies in the country, prevention of the disease through appropriate use of rabies postexposure prophylaxis is critical to save lives. This article provides a summary of rabies in South Africa and key aspects of the prevention of the disease in exposed humans

Cross-protective and cross-reactive immune responses to recombinant vaccinia viruses expressing full-length lyssavirus glycoprotein genes.

Lyssaviruses cause acute, progressive encephalitis in mammals. Current rabies vaccines offer protection against the lyssaviruses, with the notable exceptions of Mokola virus (MOKV), Lagos bat virus (LBV) and West Caucasian bat virus (WCBV). Here we describe the cross-protective and cross-reactive immune responses induced by experimental recombinant vaccinia viruses encoding the glycoprotein genes of rabies virus (RABV), MOKV and WCBV, either singly or in dual combinations. Constructs expressing a single glycoprotein gene protected mice against lethal intracranial challenge with homologous virus. Similarly, recombinants expressing glycoprotein genes from two different lyssaviruses offered mice protection against both homologous viruses. VNAb induced by vaccines that included a MOKV glycoprotein gene cross-neutralized LBV, but not WCBV. We concluded that a single recombinant poxvirus-vectored vaccine including MOKV and RABV glycoprotein genes, should be a major addition to available rabies biologics and should offer broad protection against all of the lyssaviruses, except WCBV.