ABSTRACT
Herd immunity against poliomyelitis was studied in 1391 children and adolescents from 10 towns of the Moscow Region. It was ascertained that the values of herd immunity against poliomyelitis virus type 1 were high everywhere and those of herd immunity against poliomyelitis virus type 2 were high and very high in 9 towns and below the WHO minimum levels (80%). The values of herd immunity against poliomyelitis virus type 3; they were lower than the required minimum in 2 towns and very low in 2 other towns arouse alarm. The study of strain-specific antibodies to vaccine-derived and wild polioviruses has demonstrated that wild poliomyelitis viruses have not circulated in the areas of the examinees in the past decade.
Subject(s)
Immunity, Herd , Poliomyelitis/epidemiology , Poliomyelitis/immunology , Poliovirus/immunology , Adolescent , Antibodies, Viral/blood , Antibodies, Viral/immunology , Antibody Specificity , Child , Child, Preschool , Humans , Immunization Programs/standards , Infant , Infant, Newborn , Moscow/epidemiology , Poliovirus Vaccine, Oral/immunology , Urban PopulationABSTRACT
Multiplex real-time polymerase chain reaction test-system with fluorescent detection (RT-PCR) for simultaneous identification of main agents of acute respiratory viral infections: influenza A (IAV) and B viruses (IBV), parainfluenza viruses types 1, 2, 3, 4 (PIV 1 - 4), adenoviruses (ADV), respiratory syncitial virus (RSV), rhinoviruses (RV) and enteroviruses (EV), in presence internal positive control (IPC) represented by vaccine strain of rubella virus RA 27/3. Using multiplex RT-PCR method, respiratory viruses were detected in 116 out of 226 clinical samples (nasal swabs) obtained from patients with symptoms of acute respiratory infection: in 68 (58.6%) samples--IBV; in 21 (18.1%)--IAV; in 12 (10.3%) --RV; in 6 (5.2%)--PIV 2; in 4--(3.4%) ADV; in 3 (2.6%)--RSV; in 2 (1.7%)--EV; in 2 (1.7%)--PIV 4; in 1 (0.9%)--PIV 3; in 1 (0.9%)--PIV 1. Mixed infection was observed in 4 (3.4%) patients. PCR assay allowed to reveal various respiratory viruses in 51.3% of samples. At the same time samples were tested for the presence of 12 respiratory viruses--IAV, IBV, PIV 1 - 4, RSV, RV, metapneumoviruses, and coronaviruses NL63, 229E and OC43--in the presence of IPC represented by equine arteritis virus using analogous PCR test-system provided by medical center of Leiden university. Results of tests for detection of IAV, IBV, RSV, PIV 1 - 4, and RV, analyzed by both systems, agreed in 94%. Multiplex format of RT-PCR performing significantly reduces time and cost of the test, which make it suitable and effective instrument of epidemiological studies.
