Health ecology: factors of spread and consequences of viral hepatitis manifestation Ludmila Vetrova, Tatyana Pogrebnyak, Elena Khorolskaya, Irina Sagalaeva and Darya Maslova BIO Web Conf., 30 (2021) 04009 Published online: 22 April 2021 DOI: 10.1051/bioconf/20213004009