3 Discussion
The “common cold” was not generally concerned by the general public for the mild symptoms, however, there were more than 250 virus serotypes could led to the “common cold” symptoms, and human rhinovirus (HRV) has long been known for the main pathogens of the “common cold”2,8, Cui and colleagues9 have reported that among the influenza like illness (ILI), 6.46% of which were tested positive for HRV, another study conducted by Lan Zhaoet al 10 reported that 11.28% of the acute respiratory viral infection were caused by HRV infection. Yuki Furuseet al 11. also found that rhinoviruses were the most frequently detected pathogen (22.2%) among the acute respiratory infection (ARI) cases, the hospitalized population would have a higher positive rate of HRV12.
A study conducted by Dr. Luka and colleges13 in Kenya had reported that the common cold caused by HRV was mainly detected among school-going children or teenagers with a mild acute respiratory symptoms. However, the HRV infected adults were had a relative higher mortality and longer hospitalization than that of the patients infected influenza viruses in the elderly population14. Dr. Park15 analyzed the etiological surveillance data of respiratory viruses in South Korea from 2016 to 2019 and 2020, and found that the enveloped respiratory viruses (human coronavirus, HCoV, non-SARS-COV-2; human metapneumovirus, HMPV; influenza virus, IFV; parainfluenza virus, PIV; respiratory syncytial virus, RSV) were effectively controlled at the COVID-19 control measures in 2020, while non-enveloped respiratory viruses (adenovirus, ADV; human rhinovirus, HRV; human bocavirus, HBoV) were not effectively controlled during this period, and among hospitalized cases, the proportion of hospitalizations due to rhinovirus infection was significantly increased. A study conducted by Dr. Zhang16 observed a sharp increase of the positive rate of HRV in Beijing, China, and reasonably assumed to be explained by the reopening of the primary and secondary schools of Beijing. Another study17 conducted in Southampton, UK, gave a theory that the HRV was mainly found in children and adolescents whom were the major reservoir for HRV infection, social distancing and face masks are not effective in preventing transmission of HRV, with “Back-to-School Upper Respiratory Infection ” effect18, the risk of HRV transmission surges after schools reopening. On the other hand, Dr. Nancy Leung19 conducted experiments and proved that there was no significant difference in filtering or protection effect of HRV between wearing a face mask or not, indicating that wearing masks cannot effectively protect the population from the HRV infection.
Our previous studies20-22 have showed that when combated with the COVID-19 pandemic, measures had been taken to stop the transmission of the SARS-COV-2, and respiratory virus like influenza virus, varicella, herpes zoster, rubella, measles, mumps virus were observed all dramatically decreased during the fighting against COVID-19 pandemic, however, HRV was found remains prevalent in school teenagers23.
In our study, most of the outbreaks were reported the primary and secondary schools of Guangzhou, China, which was agree with the Dr. Martha’s and Dr. Zhang’ s study13,16. 74% of the patients in our study were recorded had fever, 30% of the patients had sore throat and runny nose, 19% of the patients had cough and 8% of the patients had sneeze, so the most typical symptom of HRV infection in our study was fever. By sampling and testing, we found that patients with the symptoms of fever, cough, runny nose and sneezing were more likely to test positive for HRV in a HRV related outbreak. Study have proved that HRV infection in youngsters would be symptomatic while in adults often asymptomatic24.
Diurnal temperature range (DTR) was reported to be one of the risk factors of the common cold, which gives the answer to the trend of the endemic of HRV in spring and winter of the year25. Obesity was another risk factor reported to rise the possibility of HRV infection26. While in our study, we did not collect the DTR, height and weight data of the patients, which is a shortcoming of this study.
In summary, this study gives a glimpse of the endemic of HRV in Guangzhou, China, proved better evidence for the prevention and control of respiratory viruses, and indicated that the conventional COVID-19 control measures, such as wearing face masks or social distancing, are not effective enough in preventing rhinovirus, so new masks that filter non-enveloped viruses, including HRV, should be considered as a possible new approach to preventing HRV infection.
Funding: This work was supported by the Natural Science Foundation of Guangdong Province (2019A1515011407), Medical Science and Technology Project of Guangzhou (20201A011067,20211A011059), Guangdong Medical Science and Technology Research Project (A2019379, A2020399, B2021244).
Conflicts of Interest: No conflict of interest to declare by all authors
ORCID: Di Wuhttps://orcid.org/0000-0003-2462-4232
Ethical Approval Statement: The ethical approval or individual consent was not applicable.