Comparative pathogenicity of Coxsackievirus A16 circulating and noncirculating strains in vitro and in a neonatal mouse model

An enterovirus 71 (EV71) vaccine for the prevention of hand, foot, and mouth disease (HMFD) is available, but it is not known whether the EV71 vaccine cross-protects against Coxsackievirus (CV) infection. Furthermore, although an inactivated circulating CVA16 Changchun 024 (CC024) strain vaccine candidate is effective in newborn mice, the CC024 strain causes severe lesions in muscle and lung tissues. Therefore, an effective CV vaccine with improved pathogenic safety is needed. The aim of this study was to evaluate the in vivo safety and in vitro replication capability of a noncirculating CVA16 SHZH05 strain. The replication capacity of circulating CVA16 strains CC024, CC045, CC090 and CC163 and the noncirculating SHZH05 strain was evaluated by cytopathic effect in different cell lines. The replication capacity and pathogenicity of the CC024 and SHZH05 strains were also evaluated in a neonatal mouse model. Histopathological and viral load analyses demonstrated that the SHZH05 strain had an in vitro replication capacity comparable to the four CC strains. The CC024, but not the SHZH05 strain, became distributed in a variety of tissues and caused severe lesions and mortality in neonatal mice. The differences in replication capacity and in vivo pathogenicity of the CC024 and SHZH05 strains may result from differences in the nucleotide and amino acid sequences of viral functional polyproteins P1, P2 and P3. Our findings suggest that the noncirculating SHZH05 strain may be a safer CV vaccine candidate than the CC024 strain.

Sequence analysis of the 5′ third of glycoprotein C gene of South American bovine herpesviruses 1 and 5

Bovine herpesviruses 1 (BoHV-1) and 5 (BoHV-5) share high genetic and antigenic similarities, but exhibit marked differences in tissue tropism and neurovirulence. The amino-terminal region of glycoprotein C (gC), which is markedly different in each of the viruses, is involved in virus binding to cellular receptors and in interactions with the immune system. This study investigated the genetic and antigenic differences of the 5′ region of the gC (5′ gC) gene (amino-terminal) of South American BoHV-1 (n=19) and BoHV-5 (n=25) isolates. Sequence alignments of 374 nucleotides (104 amino acids) revealed mean similarity levels of 97.3 and 94.2% among BoHV-1 gC (gC1), respectively, 96.8 and 95.6% among BoHV-5 gC (gC5), and 62 and 53.3% between gC1 and gC5. Differences included the absence of 40 amino acid residues (27 encompassing predicted linear epitopes) scattered throughout 5′ gC1 compared to 5′ gC5. Virus neutralizing assays testing BoHV-1 and BoHV-5 antisera against each isolate revealed a high degree of cross-neutralization between the viruses, yet some isolates were neutralized at very low titers by heterologous sera, and a few BoHV-5 isolates reacted weakly with either sera. The virus neutralization differences observed within the same viral species, and more pronounced between BoHV-1 and BoHV-5, likely reflect sequence differences in neutralizing epitopes. These results demonstrate that the 5′ gC region is well conserved within each viral species but is divergent between BoHV-1 and BoHV-5, likely contributing to their biological and antigenic differences.

Off-label drug use in children.

OBJECTIVE: To determine the extent and nature of off-label drug use in children admitted to a pediatric general ward in a tertiary health care centre METHODS: Consecutive patients aged 1 mo-12 years admitted to the general wards in a tertiary care center in Mumbai over a two-month period were prospectively enrolled in the study. British National Formulary [BNF] version 2005 was used to ascertain if the drug use was "off-label". The off-label use was categorized as: administration of a greater/lesser dose, administration at a higher/lower frequency than indicated, administration for indications not described, administration of a drug not licensed for use in that age group and/ or use of alternative routes of administration. Descriptive statistics was used for calculating the off-label drug use. RESULTS: Two thousand prescriptions received by 600 subjects (M:F= 1.47:1) were analyzed. One thousand and forty-five (50.62%) prescriptions were off-label. The off-label drug use rate was 1.74+/-1.56 per patient. The maximum rate of off-label drugs was in infants (2.33/patient). 'alteration in dosage' was by far the commonest reason for off-label use; followed by 'age' and 'indication'. Furosemide (i. v.), diazepam (i.v), cefotaxime (i.v), ethambutol (tab) and prednisolone (tab) were the five commonest off-label drugs used in the study population. CONCLUSIONS: Off-label drug use was highly prevalent in general pediatric ward of a tertiary care hospital in India.

Assessing the antimicrobial prescription request process in a teaching hospital in Brazil: Regulations and training

It is kmown that antimicrobials are often prescribed inappropriately. One method used to deal with problem is to regulate antimicrobial use by monitoring prescriptions. We report a study of physician compliance with the request for antibiotic process which was prepared and reviewed by a special infection control committee in our hospital - the Nosocomial Infection Prevention Service (SCHI). The objective of this study was to identify the profile of inappropriate requests for restricted therapeutic antimicrobials used at Nossa Senhora da Conceiçäo (HNSC), in Porto Alegre, Brazil. All 3,389 requests for therapeutic antimicrobials made between May 20, and October 31, 1996, were assesed ans classified as appropriate and inappropriate. We determined that 17.8 percent of the requests were innapropriate (a total of 720 errors). These were categorized according to 12 reasons for inappropriateness. Of these, the 3 most frequent inappropriate requests were deviation from standard use (26.73 percent), inappropriate length of treatment (23.19 percent), and unfounded justification (13.61 percent). The reasons for inappropriateness were also arranged in three categories considering the following aspects:I.technical (59 percent);II.compability with the institucional program (32.36 percent), and III.administrative (8.61 percent). The 720 requests that were initially rejected were evaluated to see how antibiotic use was affected. In approximately 400 (55 percent), the forms could be appropriately modified after discussion with physician. We conclude from this study that most of the inappropriate requests for antimicrobials in our hospital can be remedied by educating the staff since the errors were largely technical in nature. Thus, the SCIH should focus more on its role as an educational rather than as a regulatory body. By expanding this educational role, we antecipate improved physician compliance with our guidelines, and more appropriate antimicrobial prescribing and and usage.