Adele Visser

Molecular epidemiological analysis of a nosocomial outbreak of respiratory syncytial virus associated pneumonia in a kangaroo mother care unit in South Africa

Respiratory syncytial virus (RSV) may cause severe lower respiratory tract disease in premature infants. Prolonged viral shedding has been reported in patients with underlying immunosuppressive disorders, such as human immunodeficiency virus 1 (HIV‐1) infection. During March to May 2006, 23 preterm pediatric patients developed nosocomial pneumonia in a district hospital in the Gauteng Province of South Africa due to RSV infection. The patients were identified using routine diagnostic testing. All had been admitted with their mothers to a Kangaroo Mother Care (KMC) ward from birth—a low care unit for the management of stable low birth weight infants. The HIV‐1 seroprevalence among the mothers to these infants was 52.6%, translating to a 52.6% perinatal exposure. A multiplex nested RT‐PCR was used to subtype RSV positive nasopharyngeal aspirates. Sequencing and phylogenetic analysis of part of the G‐protein gene was used for molecular epidemiological analysis of the outbreak. In total, 19 of the 23 RSV positive specimens could be PCR amplified and sequenced. The subtype A, GA5 genotype was identified in 14 specimens and the BA genotype, a new subtype B genotype not previously recognized in South Africa, in seven. One patient had an infection with both genotypes. Phylogenetic analysis demonstrated eight separate introductions. Two of the strains identified in this outbreak were identical to strains circulating in a general pediatric ward of this hospital during the preceding month. Inadequate infection control measures by health care providers and mothers to children in KMC units may increase potentially the risk of severe RSV infection in a population group with compounded risk factors. J. Med. Virol. 80:724–732, 2008.

Contribution of common and recently described respiratory viruses to annual hospitalizations in children in South Africa

The contribution of viruses to lower respiratory tract disease in sub‐Saharan Africa where human immunodeficiency virus may exacerbate respiratory infections is not well defined. No data exist on some of these viruses for Southern Africa. Comprehensive molecular screening may define the role of these viruses as single and co‐infections in a population with a high HIV‐AIDS burden. To address this, children less than 5 years of age with respiratory infections from 3 public sector hospitals, Pretoria South Africa were screened for 14 respiratory viruses, by PCR over 2 years. Healthy control children from the same region were included. Rhinovirus was identified in 33% of patients, RSV (30.1%), PIV‐3 (7.8%), hBoV (6.1%), adenovirus (5.7%), hMPV (4.8%), influenza A (3.4%), coronavirus NL63 (2.1%), and OC43 (1.8%). PIV‐1, PIV‐2, CoV‐229E, ‐HKU1, and influenza B occurred in <1.5% of patients. Most cases with adenovirus, influenza A, hMPV, hBoV, coronaviruses, and WU virus occurred as co‐infections while RSV, PIV‐3, and rhinovirus were identified most frequently as the only respiratory pathogen. Rhinovirus but not RSV or PIV‐3 was also frequently identified in healthy controls. A higher HIV sero‐prevalence was noticed in patients with co‐infections although co‐infections were not associated with more severe disease. RSV, hPMV, PIV‐3, and influenza viruses had defined seasons while rhinovirus, adenovirus, and coronavirus infections occurred year round in this temporal region of sub‐Saharan Africa. J. Med. Virol. 83:1458–1468, 2011.

Human polyomaviruses, WU and KI in HIV exposed children with acute lower respiratory tract infections in hospitals in South Africa.

Abstract Background The importance of two recently identified polyomaviruses, WUV and KIV, as respiratory pathogens in populations with a high HIV prevalence needs to be defined, since human polyomaviruses can cause significant morbidity and mortality in patients with immunosuppression. Geographic distribution and disease association of WUV and KIV genotypes are not yet clearly defined. Objectives To investigate the prevalence of WUV and KIV in HIV-positive and HIV-negative patients with respiratory infections in hospitals in South Africa and determine their genotypes. Study design Specimens from patients with acute respiratory infections from hospitals serving Pretoria were screened for WUV and KIV. Positive specimens were sequenced and subjected to phylogenetic analysis. Results WUV was identified in (7%) and KIV in (1%) of mainly pediatric patients. Co-infections were common in WUV- and KIV-infected patients (71% and 66.6%, respectively); 57% of patients with WUV and 33% of patients with KIV were HIV-positive while the HIV prevalence in the respiratory virus patient group screened in this study was 33% WUV and KIV patients presented with moderate to severe lower respiratory tract disease. Four distinct and 2 unique WUV strains were identified clustering into 2 of 4 globally identified genotypes. KIV strains were identical to strains from Sweden. Conclusion WUV is frequently detected in HIV-infected patients with respiratory disease, but its role as respiratory pathogen remains uncertain.

Haemophilus influenzae type b conjugate vaccines - a South African perspective.

Introduction of Hib vaccine is known to positively impact on reduction of both morbidity and mortality in children less than 5 years of age. Incorporation of this vaccine into a National EPI, however, does come at a significant cost, which is especially important in non-GAVI funded countries. Compounded reduction in response in certain patient populations and possible indication of booster doses further impacts on cost-benefit analyses. Despite these issues, South Africa has supplied Hib vaccine as part of the National EPI in the form of a combination vaccine, Pentaxim, which combines Hib with Diphtheria, Tetanus, acellular Pertussis (DTP) and Poliomyelitis since 2009. Prior to this, another combination vaccine was utilized containing Hib and DTP. This has subsequently lead to a significant reduction in invasive Hib disease post-introduction, therefore largely justifying utilization.

DECREASED CD10 EXPRESSION IN THE BONE MARROW NEUTROPHILS OF HIV POSITIVE PATIENTS

Background: HIV-1 infection is associated with various quantitative and qualitative changes in haemopoietic cells. Clear distinction between primary myelodysplastic syndrome (MDS) and secondary dysplasia may not always be possible. Adjunctive analyses used in the diagnosis of MDS include cytogenetics and flow cytometry (FCM). Much focus has been placed on establishing FCM guidelines aiding in the diagnosis of MDS, and to distinguish this condition from secondary dysplastic changes. One of the parameters often cited is the CD10 expression on the granulocyte population, as this marker denotes granulocytic maturation. Aims: To determine the expression level of CD10 on granulocytes in HIV positive patients. Methods: In total, 117 HIV-1 positive and 29 HIV-1 negative patients were included in this study. Bone marrow aspirate samples were evaluated in terms of morphological abnormality as well as CD10 expression on the granulocytic population. Results: The average CD10 expression among the HIV-1 positive patients were markedly reduced, at 18.4%, and 113 patients (96.6%) of these patients had expression levels below 50%. Discussion: Disease conditions causing secondary dysplasia, especially HIV-1 infection, is associated with a marked reduction in CD10 expression on the granulocyte population independent from the presence of myelodysplastic features. This marker is therefore of doubtful significance as a diagnostic tool in distinguishing between primary and secondary dysplasia.

Reality bites of spider bites: a case report and review of the local epidemiology

Spider bites are a frequent complaint, often prompting patients to seek medical attention. 1 However, the diagnosis of a spider bite is frequently inferred by the patient, and a thorough evaluation subsequently reveals an alternate diagnosis. Gertsch et al demonstrated that of 600 consecutive “spider bite” cases, 80% were incorrectly diagnosed. 2 Alternative diagnoses included bites by arthropods other than spiders, 2 bacterial, viral or fungal infections 3 and malignant tumours. 3 In this study, we describe the case of a patient who was initially misdiagnosed as having been bitten by a spider. Later, the patient was demonstrated to have a spontaneous, soft tissue Staphylococcus aureus infection. We further describe the local epidemiology of cases presenting with spider bites and the subsequent microbiological findings.

Patient with protracted abdominal pain

Actinomycosis is very often misdiagnosed as typically, the associated laboratory and radiological findings are nonspecific. Therefore, clinicians should always have a high index of suspicion in cases in which there is a chronic, indolent development of a mass lesion with sinus tracts, that progresses through the tissue planes, and which relapses following short courses of antibiotics. 1 Early diagnosis may prevent invasive investigations and radical surgical procedures as the patient can then simply be treated with oral penicillin. 2

Disseminated skin lesions in a patient with AIDS

Patients with advanced HIV-1 disease can present with a vast array of opportunistic infections. Not only is the spectrum of disease more diverse, but the spectrum of presentation can vary significantly from what is expected. In this case report we describe a patient with advanced HIV-1 disease presenting disseminated skin lesions and haematological abnormalities. Upon further investigation, a probable diagnosis of disseminated histoplasmosis was established. The patient was subsequently treated with oral itraconazole and showed marked haematological and clinical improvement within six weeks of therapy. Histoplasmosis is an opportunistic infection endemic to South Africa and, like most opportunistic infections, can present with a myriad of clinical features which can complicate early diagnosis. Although not as prevalent as in other parts of the world, it should always be considered as part of the differential diagnosis, especially among severely immunocompromised individuals.