Diagnostic tools used in the evaluation of acute febrile illness in South India: a scoping review
BMC INFECTIOUS DISEASES
Authors: Bhaskaran, Divyalakshmi; Chadha, Sarabjit Singh; Sarin, Sanjay; Sen, Rajashree; Arafah, Sonia; Dittrich, Sabine
Abstract
Background Acute febrile illness (AFI) is characterized by malaise, myalgia and a raised temperature that is a nonspecific manifestation of infectious diseases in the tropics. The lack of appropriate diagnostics for the evaluation of AFI leads to increased morbidity and mortality in resource-limited settings, specifically low-income countries like India. The review aimed to identify the number, type and quality of diagnostics used for AFI evaluation during passive case detection at health care centres in South India. Methods A scoping review of peer-reviewed English language original research articles published between 1946-July 2018 from four databases was undertaken to assess the type and number of diagnostics used in AFI evaluation in South India. Results were stratified according to types of pathogen-specific tests used in AFI management. Results The review included a total of 40 studies, all conducted in tertiary care centres (80% in private settings). The studies demonstrated the use of 5-22 tests per patient for the evaluation of AFI. Among 25 studies evaluating possible causes of AFI, 96% tested for malaria followed by 80% for dengue, 72% for scrub typhus, 68% for typhoid and 60% for leptospirosis identifying these as commonly suspected causes of AFI. 54% studies diagnosed malaria with smear microscopy while others diagnosed dengue, scrub typhus, typhoid and leptospirosis using antibody or antigen detection assays. 39% studies used the Weil-Felix test (WFT) for scrub typhus diagnosis and 82% studies used the Widal test for diagnosing typhoid. Conclusions The review demonstrated the use of five or more pathogen-specific tests in evaluating AFI as well as described the widespread use of suboptimal tests like the WFT and Widal in fever evaluation. It identified the need for the development of better-quality tests for aetiological diagnosis and improved standardised testing guidelines for AFI.
Genetic heterogeneity of canine bufaviruses
TRANSBOUNDARY AND EMERGING DISEASES
Authors: Di Martino, Barbara; Sarchese, Vittorio; Di Profio, Federica; Palombieri, Andrea; Melegari, Irene; Fruci, Paola; Aste, Giovanni; Banyai, Krisztian; Fulvio, Marsilio; Martella, Vito
Abstract
Canine bufavirus (CBuV) is a protoparvovirus, genetically related to human and non-human primate bufaviruses and distantly related to canine parvovirus type 2 (CPV-2). CBuV was initially identified from young dogs with respiratory signs but subsequent studies revealed that this virus is also a common component of the canine enteric virome. In this survey, by assessing archival and recent collections of dogs faecal samples, CBuV DNA was detected with a higher prevalence rate (8.8%) in animals with enteritis than in control animals (5.0%), although this difference was not statistically significant. The rate of co-infections with other enteric viruses in diarrhoeic dogs was high (84.6%), mostly in association with canine parvovirus CPV-2 (90.1%). The complete ORF2 gene was determined in five samples, and the nearly full-length genome was reconstructed for three strains, 62/2017/ITA, 9AS/2005/ITA and 35/2018/ITA. Upon sequence comparison, the viruses appeared highly conserved in the NS1 (97.2%-97.9% nt and 97.5%-98.1% aa identities). In the complete VP2 coding region, three strains were similar to the prototype viruses (99.7-99.8 nt and 99.6%-99.8% aa) whilst strains 9AS/2005/ITA and 35/2016/ITA were distantly related (87.6%-89.3% nt and 93.9%-95.1% aa identities). Interestingly, genetic diversification occurred downstream conserved regions such as the VP1/VP2 splicing signals and/or the G-rich motif in the N terminus of the VP2, suggesting a potential recombination nature. Upon phylogenetic analysis, the two divergent CBuV strains formed a distinct cluster/genotype.