Survival factors affecting the infectivity of hepatitis A virus isolated from Egypt

Document Type : Original Article


Botany and Microbiology Department, Faculty of Science, Al-Azhar University, 11884 Nasr City, Cairo, Egypt


Background: The physicochemical properties of viruses affect both how well they spread and how long they may survive in different environments. It would be helpful to have a complete understanding of the tools to break or limit the chain of virus transmission. In addition to choosing safe circumstances for preventing infections and the spread of these viruses. Methods and results: The data obtained demonstrated that hepatitis A viruses (HAV) were stable at freezing (–20°C). HAV's infectivity was considerably impacted by the temperature increase (70oc), with a 4.77 log10TCID50/ml titer drop. HAV was resistant to various pH levels. At pH 4 the virus titer decreased by 0.88 log10TCID50/ml. However, the virus was entirely inactivated at pH 12. The minor titer decreased by 0.54 log10TCID50/ml at 3% salt conc., indicating that HAV was salt stable. Virus deactivation by disinfectants (ethanol 20, 70 and 95%), phenol (1, 2 and 3), chlorine (5, 10 and 20 mg/l). Iodine (0.5, 1 and 3%) was performed. The exposure to 70% ethanol, a partial inactivation of 4.16 log10TCID 50/ml was detected. In contrast, HAV was completely inactivated at 3% phenol, while at 1 and 2% it maintained its infectivity. The virucidal efficiency of chlorine was detected at 20 mg/l, while at 5 and 10 mg/l, the titer was decreased by 0.86 and 6.19 log10TCID50/ml, respectively. Iodine at all measured concentrations did not show a complete ability to fully integrate HAV. Conclusion: HAV is very stable and somewhat resistant to environmental influences, acidic pH, high temperature and chemicals.


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