Recently, the number of patients with influenza in fever clinics across Guangdong has increased dramatically. According to the influenza surveillance data from Guangdong CDC, the percentage of outpatient visits for influenza-like illness has reached 7.29%, and about 7 out of 100 outpatients are infected by flu, which indicates that Guangdong has entered flu season in summer.
"Data shows the percentage of influenza-like cases in this flu season has exceeded the level of the same period in 2021 and 2020, and the positive rate has also seen a year-on-year increase," said Kang Min, Director of the Institute for the Prevention and Control of Infectious Diseases of Guangdong CDC.
Why is this influenza wave in Guangdong so severe in June? How to prevent it?
(Source: Guangdong CDC)
Multiple factors lead to the increasing number of outpatients at fever clinics
"Starting from June, the number of patients admitted to fever clinics in our hospital has been 600 to 700 per day, which is twice as usual, and a significant increase year on year," said Deng Wen, Director of the Emergency Department of Guangdong Women and Children's Hospital.
Deng mentioned the growth in the number of people seeking medical attention is due to people's habit of visiting a doctor in a timely manner during the epidemic, as well as the rainy weather in this summer.
"Affected by the epidemic, Guangdong has improved fever clinics. The government recommends that residents with a fever or other related symptoms should receive early diagnosis and treatment." Deng said, "Moreover, as June is the exam season, students should also seek medical treatment in a timely manner."
Kang Min noted that according to the influenza surveillance data from Guangdong CDC, the proportion of secondary school students and children who seek medical treatment was higher than adults, "We should never lower our guard in protecting children's health."
In addition to Guangdong, Jiangxi, Guangxi, and Fujian have also entered the summer flu season.
Kang said that the transmission of the flu virus is owing to the population flow, and weather conditions, especially the hot and humid weather in Guangdong. "Studies have shown that influenza viruses are easy to spread at a certain temperature during summer. As southern provinces enter summer, people's activities and the population flow increase. When air conditioners are turned on in most closed indoor places, it's easy to transmit the virus."
He also mentioned that due to the impact of the COVID-19 over the past two years, residents have made it a habit to wear masks. The level of influenza infection in Guangdong has been low; meanwhile, there are a large number of susceptible people. "This year, due to the fast mutation of the influenza virus, people are more susceptible to its infection."
The wave of influenza is expected to be high in intensity, however, short in duration
Guangdong's influenza pathogen surveillance results show that the dominant influenza strain in Guangdong is Subtype H3N2 influenza A viruses (A (H3N2)). A(H3N2), a common influenza subtype, that spread in Guangdong in the summers of 2015 and 2017.
"The Influenza A H3N2 variant viruses are very easy to be transmitted in summer." According to Kang, influenza viruses are divided into four types: A, B, C, and D. Current subtypes of influenza A and B viruses that routinely circulate among people include: A(H1N1) pdm09, A(H3N2), and B/Yamagata, B/Victoria.
Compared with the other three influenza viruses, the H3N2 strain has a higher incidence rate with higher intensity, but its duration will be shorter.
Kang emphasized that the H3N2 strain features fast mutation, and it is suggested to get the latest influenza vaccine every year.
Although the H3N2 strain has mutation, Kang Min mentioned that "everyone can rest assured because the existing antiviral drugs are still effective and its virulence has not changed fundamentally."
These people should seek medical treatment in a timely manner
Li Zengqing, Director of the Pediatric Respiratory Department of Guangdong Women and Children's Hospital, said that the main symptoms of flu are fever, cough, sore throat, headache, muscle pain, chills, fatigue, and loss of appetite. Most patients’ body temperature will gradually lower and their systemic symptoms improve 3 or 4 days after they develop symptoms. However, cough may last for 1-2 weeks.
"Compared with the common cold, the obvious symptoms of this wave of flu are muscle soreness, fever, and even alternating hot and cold feelings." Deng Wen said that infants, pregnant women, and the elderly with underlying diseases are prone to risk groups for severe influenza, and special attention should be paid.
Li Zengqing warned that apart from the elderly, some infants with underlying diseases will develop serious symptoms after contracting influenza viruses, for example, children with encephalitis, complex congenital heart disease, neuromotor dysfunction, delayed motor development, and low immune function, as well as babies under 6 months. "Parents should pay close attention to children's condition and seek medical attention in a timely manner."
Deng advised that in daily influenza prevention, residents need to develop good diet, hygiene and exercising habits to improve immunity. As Guangdong is rainy and hot in summer, windows should be opened regularly to keep the room well-ventilated.
"The elderly, patients with underlying diseases, pregnant women and children should rest at home after contracting the flu. Always observe their condition and seek medical attention in a timely manner." Kang reminds residents to wear a mask when going out, keep hands hygienic, avoid direct contact with items in public places, cover mouth and nose with a tissue or towel when coughing or sneezing, wash hands regularly, and avoid touching eyes, nose or mouth with hands.
He also said attention should be paid to the overlapping risk of influenza and COVID-19. "They are both respiratory infectious diseases, showing similar early symptoms. Therefore, preventive measures against respiratory disease transmission can and should be taken to prevent both flu and COVID-19."
Guangdong CDC suggests that vaccination against influenza is still the most effective means of prevention. It is recommended that residents get vaccinated every year, which can significantly reduce the risk of serious complications.
Author | Hannah, Krystal (intern)
Editor | Wing, Nan, Will, Jerry
