Epidemiology of Influenza Viruses and Viruses Causing Influenza-Like Illness in Children Under 14 Years Old in the 2018-2019 Epidemic Season in Poland

Abstract

Background This study aimed to investigate the epidemiology of influenza viruses and viruses that caused influenza-like disease in children under 14 years of age in the 2018–2019 epidemic season in Poland, and to identify the public health lessons that can be learned. Material/Methods Nose and throat swabs were used to obtain samples. The samples were analyzed in the National Influenza Center, Department of Influenza Research at the National Institute of Public Health-National Institute of Hygiene as well as in 16 Voivodship Sanitary Epidemiological Stations across the country. Methods of RNA isolation depended on the laboratory where the isolation was performed. In all laboratories, quantitative polymerase chain reactions were used to determine the influenza virus type as well as the subtype. Results The study group was confirmed to be infected with influenza A and B, with influenza A/H1N1/pdm09 as the dominant subtype. Among the age group of children up to 14 years of age, cases of infection with viruses that cause influenza-like disease were also reported. It was noticeable that the largest number of confirmed cases of infection was recorded in the group of the youngest children (0–4 years). In addition, several different variants of co-infection were registered. Conclusions This population study showed that in the 2018–2019 epidemic season in Poland children aged under 14 years were at risk of influenza virus infection and its complications. The presented data support increasing the percentage of children being vaccinated in Poland.

Pathogenic changes of community-acquired pneumonia in a children’s hospital in Beijing, China before and after COVID-19 onset: a retrospective study

“…The reduction in MPP may be affected by the epidemic year to some extent, but we still believe that it was mainly due to the mitigation measures that rates of MPP were so drastically reduced. In addition, IV is a common pathogen of CAP in children in the winter season, and studies have shown that IV also easily causes outbreaks on school campuses and in kindergartens [ 10 , 11 ]. The mitigation measures were beneficial to restrain the spread of MP and IV in the first place.…”

Influenza and Influenza-Like Respiratory Virus Infections in Children During the 2019/20 Influenza Season and the COVID-19 Pandemic in Poland: Data from the National Influenza Centre, the Department of Influenza Research at the National Institute of Public Health, and 16 Voivodeship Sanitary and Epidemiological Stations

“…Similar tendencies can be noticed both in other European countries, as well as in the rest of the world [ 13 ]. In the season 2019/2020, activity of influenza A/H3N2/ and B were increased in relation to the influenza season 2018/2019 [ 14 ]. The highest number of infections with both influenza viruses and influenza-like viruses was recorded among the youngest children aged 0–4 years.…”

“…The highest number of infections with both influenza viruses and influenza-like viruses was recorded among the youngest children aged 0–4 years. [ 14 ]. This confirms that younger age is associated with a less mature immune system and greater vulnerability to viruses.…”