Why did the number of flu cases increase after Tet?

According to Dr. Truong Huu Khanh, Vice President of the Ho Chi Minh City Infectious Diseases Association, the increase in cases during Tet is due to the prolonged cold weather, which creates favorable conditions for the flu virus to survive longer in the environment, thereby developing and spreading the disease. Cold and humid air also makes respiratory cells vulnerable, the body's immune response is reduced, making it easier for the flu virus to penetrate.

Statistics show that in January, the temperature in the whole country was 0.5-1.5 degrees lower than the average of many years, and even lower in some places. In recent days, the northern provinces and cities have been immersed in cold weather day and night, with some places down to 1 degree Celsius. It is forecasted that in February, cold air will continue to spread to the North.

In addition, Tet is also the time when people travel and gather a lot, especially in tourist spots, public areas, entertainment venues, and crowded parties. These things also give the flu virus the opportunity to spread widely and break out in many places.

Dr. Le Quoc Hung, Head of the Department of Tropical Diseases, Cho Ray Hospital, explained that the reason why it is called seasonal flu is because the disease often breaks out seasonally, especially in winter and spring with cold and humid weather. In addition to weather factors and the early-year holiday season, some researchers are raising the issue of whether immunity is weakened during the Covid-19 period due to interrupted vaccination and less exposure to common pathogens.

According to Dr. Hung, influenza can cause many dangerous complications such as pneumonia, bronchitis, otitis media, myocarditis... In particular, pneumonia progresses very quickly and severely, can take the lives of patients, especially those with weak immune systems such as children, the elderly, people with underlying diseases, autoimmune diseases, overworked people, pregnant women...

"The disease can become severe due to improper initial treatment, going to the hospital at the wrong time, or inappropriate treatment," the doctor said.

The Ministry of Health recorded a local increase in flu cases from the end of 2024 and the Tet holiday, the main agents were A/H3N2, A/H1N1 and influenza B viruses, with no unusual strains. Some northern hospitals recorded a high number of cases, many requiring ventilators, and some deaths. At the Department of Tropical Diseases and Harm Reduction Intervention, Hanoi Medical University Hospital, the number of flu patients in January was 6 times higher than in December 2024. The National Children's Hospital, the Tropical Disease Center of Bach Mai Hospital, and the National Geriatric Hospital also recorded a similar situation. Severely ill patients are often elderly people with underlying diseases.

Many East Asian countries and territories are experiencing the worst seasonal flu outbreak in years, overwhelming hospitals and leaving medicines in short supply. Japan is grappling with its worst flu outbreak in decades, with cases hitting a record high since 1999. Since early January, South Korea has reported its worst flu outbreak since 2016.

Depending on the type of virus, influenza can cause symptoms and progression of different severity. The three strains of influenza virus that affect humans are influenza A, B, and C. Of these, influenza A is the most common and causes dangerous complications, leading to many epidemics and pandemics in many countries. This strain of influenza often combines H and N antigens to create pathogens such as H5N1, H3N2, H1N1, etc. Influenza A often has new variants that change every year and are highly contagious.

Flu often causes sudden high fever, headache, body aches, chills, sore throat, dry cough, runny nose, watery eyes, loss of appetite... Most of these symptoms disappear on their own after about 7-10 days. Some severe complications that are not treated promptly can be fatal, with symptoms of difficulty breathing, shortness of breath, and high fever lasting more than two days.

People with flu need to rest, drink enough water, use antipyretics and pain relievers as prescribed by their doctor. Do not use antibiotics without a doctor's prescription. In severe cases, hospitalization is required for active treatment. Do not be subjective when signs of worsening are present. In addition to complications of pneumonia, people with flu are also susceptible to death due to secondary infections with other dangerous bacteria and viruses such as pneumococcus.

Prevent influenza by getting vaccinated every year, especially for people in high-risk groups. Disinfect, clean the throat, maintain oral hygiene every day. Wear a mask, avoid crowded places, avoid contact with people at risk of influenza. Wash your hands regularly. Eat and rest properly to have resistance, avoid catching a cold in the elderly.