Let Data Talk: Is Nature or Humans to Blame for the Outbreak of Influenza this Winter? (1)

Influenza has started to outbreak in China recently: a small community clinic near the community I live was crowded with over 100 child patients who were receiving IV, and my WeChat friend circle was flooded with various miserable situations of pediatric outpatient departments. Anxious parents were waiting in long lines with crying children at the pediatric department and emergency department of each hospital, and pediatricians were already exhausted. With this opportunity, many so-called "noble and unsullied" people have again criticized the recent abominable medical troubles and blamed them for the huge drain of pediatricians that lead to today’s bad consequences of overcrowded pediatric departments and serious shortage of medical staffs.

The main reason for the repeated outbreak of influenza every year lies in that there are various influenza virus subtypes with high mutation rate, resulting in the attacking influenza strains to be different every year. Nonetheless, there are still prevention and control methods. WHO will predict the virus strains that may be epidemic in the next year basically based on the influenza strains of previous year and prevent the outbreak of influenza by preparing and inoculating influenza vaccines in advance.

Before analyzing whether is nature or humans to blame for the outbreak of influenza this year, let’s first see the differences of the influenza this year from WHO’s global epidemiological statistics for 2017 influenza.

According to statistical data of WHO, averagely up to 650 thousand people die of respiratory diseases linked to influenza every year. WHO issued the influenza epidemiological report (Fig. 1) on January 7, 2018, with statistics of specimen data from the National Influenza Centres (NICs) and other national influenza laboratories from 105 countries for the period from December 11-24, 2017, from which, we can find that the East Asian region including China, the Europe and North Africa were regions with the most serious influenza, and China was not the only exception.

Fig. 1 Regional Distribution Map of Global Influenza Epidemiology (2018)

Analysis of epidemic virus strains of influenza in the world

The WHO GISRS laboratories analyzed 179,990 specimens, wherein, 40,431 were positive for influenza viruses, of which 26,351 (65.2%) were typed as influenza A and 14,080 (34.8%) as influenza B. In the further analysis, of the sub-typed influenza A viruses, 3,357 (30.7%) were influenza A (H1N1)pdm09 and 7,582 (69.3%) were influenza A(H3N2); of the characterized B viruses, 5,620 (86.3%) belonged to the B-Yamagata lineage and 891 (13.7%) to the B-Victoria lineage (Fig. 2).

Fig. 2 Number of Outbreak of Influenza Virus by Subtype (Specimen Data in December 2017)

Analysis of epidemic virus strains of influenza in China

Let’s focus on this winter influenza outbreak at the end of 2017 and beginning of 2018 in China. From the data in Fig. 3, the epidemic virus this winter in China is mainly the Yamagate lineage in influenza B, different from the epidemic influenza A mainly in the world, and from the influenza strains that outbroke in spring and middle of 2017.

After reading the above WHO’s data statistics, let’s analyze whether is nature or humans to blame for the outbreak of this winter influenza at the end of 2017 and beginning of 2018 in China.

Keep reading: Let Data Talk: Is Nature or Humans to Blame for the Outbreak of Influenza this Winter? (2)