A typical flu season going viral

On a café terrace, three friends are catching up over coffee. Between sips, they trade stories of fever, fatigue and missed workdays. None of them has escaped the flu at the start of the year, nor has anyone they know. “It’s everywhere,” one of them says. “This outbreak just doesn’t seem to end.”

Unlike last year, when the flu got off to a slow start, this year a large number of people have caught it early. Experts point to several contributing factors. “This is the first year since the end of the COVID pandemic (2020-2023) and the war (the Israeli conflict in 2024 editor’s note) that Lebanon is receiving such a large number of tourists and expatriates,” explains Dr. Atika Berry, director of the Preventive Medicine Department at the Ministry of Public Health (MoPH). This is compounded by the cold weather, as flu viruses thrive in low temperatures.

“As a result, the epidemic reached its peak earlier,” she adds.

Nevertheless, influenza indicators remain within seasonal norms, according to the epidemiological surveillance program at the MoPH, which meets every two weeks.

In its latest report, dated January 2, the program states that over the past four weeks, 90 patients admitted to five hospitals in Beirut, Mount Lebanon, the North and Baalbek, across both the public and private sectors, were enrolled in the severe acute respiratory infection surveillance. None tested positive for COVID-19, while 27 patients (30%) tested positive for influenza.

Over the same period, 210 patients were enrolled through the influenza-like illness surveillance across nine medical centers in Beirut, Mount-Lebanon, North, Akkar, Nabatieh and Bekaa. Among them, three patients (1.4%) tested positive for COVID-19, and 60 (28.6%) tested positive for influenza. All enrolled patients in both groups had fever and cough, which began within the previous ten days.

Different types of viruses

For context, the World Health Organization (WHO) defines seasonal influenza, or flu, as “an acute respiratory infection caused by influenza viruses.” The WHO identifies four types of influenza viruses, A, B, C and D, noting that “influenza A and B viruses circulate and cause seasonal epidemics of disease.” According to the UN organization, flu “is common in all parts of the world” and “spreads easily between people when they cough or sneeze.” “Most people recover without treatment,” the WHO adds.

Slight drift

Another factor behind this year’s early flu peak is an antigenic drift in the A(H3N2) virus, the strain most commonly detected in this season’s epidemic. Dr Berry explains that flu viruses “undergo a slight drift every year.” “This is why the composition of the flu vaccine is reviewed each year and updated to include the latest circulating strains,” she notes. However, the new clade of A(H3N2) currently circulating, known as clade K, had not yet emerged when the vaccine was developed. As a result, it is not the same strain included in this season’s vaccine. “Despite this, the vaccine remains the best form of prevention and continues to provide protection,” Dr. Berry stresses.

As the Centers for Disease Control (CDC) notes, “the seasonal flu vaccine is designed to protect against the three influenza viruses – two type A viruses and one type B virus – expected to circulate most widely during the upcoming season.” Over the past decades, the most common circulating strains have been A(H3N2), A(H1N1), and B(Victoria).

“We recommend that people at risk continue to get vaccinated against the flu, even though clade K is not included in the vaccine,” Dr Berry points out, “since it reduces the severity of the illness and, in most cases, prevents hospitalization.”

Vaccination is never too late

For Dr. Berry “it is never too late to get vaccinated, since the antibodies are developed within ten to fourteen days following vaccination.” The MoPH recommends vaccination mainly to the elderly (above 65 years), infants (over 6 months), patients with cardiovascular and chronic diseases (diabetes, hypertension), those with chronic respiratory diseases (COPD, asthma, chronic bronchitis), people with immunodeficiency and renal insufficiency, smokers, and pregnant women. The vaccine is also recommended for healthcare workers, including nurses and doctors, since they are at higher risk of exposure to flu.

Patients should consult their doctor to see which flu vaccine is suitable, since some vaccines are made from inactivated (killed) virus, while others use a live attenuated virus, which is not recommended for certain groups.

Approximately 200,000 doses of the flu vaccine were made available on the Lebanese market by the end of last August. The MoPH also imported 10,000 doses, which were administered to elderly residents in nursing homes.

“Unfortunately, the supply wasn’t sufficient,” Dr. Berry says. “In the past, nearly 500,000 doses were imported each year. However, the COVID-19 experience created some vaccine hesitancy due to side effects, which, it should be noted, remain far less severe than the disease itself. For some time now, people have started receiving the vaccine again.”

Symptoms and prevention

Clade K is characterized by rapid spread and more severe symptoms, such as fatigue and fever that last longer, “but it does not lead to an increase in ICU admissions or in the mortality rate,” according to the MoPH.

Dr. Abdul Rahman Bizri, infectious disease specialist, explains that symptoms of the flu include mainly fever, cough, sneezing, headache, extreme fatigue, as well as muscle and joint pain. “The symptoms that worry us most are shortness of breath, because we know that the A(H3N2) virus affects the lungs and can facilitate the entry of bacteria and fungi, leading to severe pneumonia,” Dr. Bizri explains.

Emphasizing the importance of vaccination, he reminds people of basic respiratory hygiene: sneeze or cough into your sleeve, wash your hands frequently especially after coughing or sneezing, avoid hugging someone who is ill, stay away from sick individuals if you are at high risk, wear a mask if you have symptoms, or stay home.

Dr. Bizri adds that if someone catches the flu, it is recommended to drink plenty of fluids, especially water. Depending on the case and medical advice, antiviral medication may be prescribed, as the earlier it is administered, the more effective it is. In some cases, the doctor may also prescribe antibiotics if needed,” he says.

In conclusion, proper precautions are recommended during flu season, such as staying warm and stocking up on vitamins, to avoid being bedridden for weeks.