Standardization of a Protocol for Quantitative Evaluation of Anti-Aerosolized Influenza Virus Activity by Vapors of a Chemically-Characterized Essential Oil Blend

Abstract

The aim of this research is to standardize the conditions of a constructed impinger, enabling to evaluate quantitatively the anti-aerosolized H9N2 avian influenza virus (AIV) activity by vapors of a chemically-characterized essential oil blend. The standardization resulted in 100% recovery of the aerosolized H9N2 virus when the impinger's conditions were set at aerosolized viral particles count of 1.2 × 10 6 /c.c. of Tryptose Phosphate Broth, temperature of 35°C, average micelle diameter of 44.3 μm, negative pressure of 6 mbar, air-suspension time of H9N2 virus of 1.5 min, collection chamber and its transport medium volumes of 250 cc and 25 cc, respectively. The adoption of the above standardized conditions, with an inclusion of vaporized essential oil (EO) at 1.0 × 10 -4 μl EO/μl volume of the pulverization chamber, and contact times of 0.5-1.5 min with the H9N2 virus, resulted in 84.6% reduction in viral titer at 1.5 min contact time, compared to the control virus, deprived from contact with vaporized EO (P<0.05). This new finding will help in future investigations related to application of safe essential oils in reduction of air-suspended influenza virus in closed systems harboring domestic animals and human populations.

Chemical composition and antimicrobial study of Crossobamon orientalis body oil

“…Earlier studies [ 24 , 44 ] corroborate with these antiviral findings. The IBV development was totally limited by n -hexane extract having 0 HA titer.…”

Antiviral and Virucidal Properties of Essential Oils and Isolated Compounds – A Scientific Approach

“…In a standardized protocol for quantitative evaluation of antiaerosolized AIV-A H9N2 activity by vapors of a well-characterized EO blend (using constructed impingers/glass chambers), Kumosani et al [65] showed that in contrast to the control (viral particles count: 1.2 × 10 6 /cm 3 ), within 1.5 min of contact time, a vaporized EO blend (equivalent volumes of eucalyptus oil with 42.2 % 1,8-cineole and peppermint oil with 48.7 % menthol) reduced the virus titer (aerosolized viruses) by about 84.6 % at a concentration of 1.0 × 10 −4 µL EO/µL air volume.…”

A perspective of the prevalent H9N2 virus with a special focus on molecular and pathological aspects in commercial broiler chicken in Punjab, Pakistan

“…Based on the amino acid sequence spanning the cleavage site of the HA protein, AIVs are phenotypically distinguished into low-pathogenic avian influenza virus (LPAIV) and high-pathogenic avian influenza virus (HPAIV) (Sultan et al, 2017). LPAIVs have mono or dibasic cleavage sites at their HA cleavage site, allowing only proteases (trypsin-like) to cleave them in the respiratory and digestive systems and are characterized by low pathogenicity as measured by the intravenous pathogenicity index (Kumosani et al, 2017). On the other hand, HPAIVs have polybasic cleavage sites that allow them to replicate in various organs, including vascular endothelium and perivascular endothelial cells resulting in high pathogenicity in chickens (Ali et al, 2021).…”