Influenza, commonly known as the flu, remains one of the most persistent viral illnesses affecting millions of people around the world each year. Spread mainly through respiratory droplets, the virus can move quickly through communities, especially during seasonal outbreaks. In recent months, health experts have raised concern as influenza cases continue to rise, placing pressure on healthcare systems and increasing the risk for vulnerable groups such as children, the elderly, and people with weakened immune systems.
The Ministry of Health (MoH), through it’s Director Dr Patrick Amoth issued a warning regarding a surge in influenza cases across Kenya, signaling the start of the peak flu season which typically runs from late February to May. As the country enters the flu season, understanding the nature of the influenza virus, its impact, and the importance of prevention has become more critical than ever.
Flu is a contagious illness caused by the influenza virus and affects the tissues in the nose, throat, and, to some degree, the lungs. It can cause severe illness and, at times, may lead to death. Flu is accompanied by symptoms such as fever, a runny or stuffy nose, fatigue, headache, and sore throat. Some people may also experience diarrhoea and vomiting, although this is more common in children than in adults.
Some people, however, do not show any symptoms of the flu. According to a household study conducted during the 2017–2023 flu seasons, about 8% of people who tested positive for influenza had no symptoms. This can be risky because a person may spread the disease unknowingly before realizing they are infected. It is also important to note that people with flu are more contagious within the first three days of their illness. Healthy adults may infect others starting from the first day, even before symptoms appear.
Immunity is another important factor when it comes to the influenza virus. People with weakened immune systems tend to be more severely affected and may remain contagious for a longer period of time. This group also includes children and the elderly.
People at Risk
Flu can affect anyone, including healthy individuals. However, some people are at a higher risk of developing flu-related complications if they become infected. Adults aged 65 years and above, as well as people with chronic medical conditions such as asthma and heart disease, are more vulnerable. Pregnant women and children under the age of five are also considered high-risk groups.
How It Spreads
Influenza spreads easily, especially in crowded places such as schools and nursing homes. The virus is mainly transmitted through droplets released when an infected person coughs or sneezes, or through contact with contaminated hands or surfaces. To reduce transmission, people should cover their mouth and nose when coughing or sneezing and wash their hands regularly.
The incubation period is usually about two days but can range from one to four days. Most influenza cases are diagnosed clinically, although laboratory tests using respiratory samples may be required to confirm the infection and distinguish it from other respiratory viruses.
Influenza viruses are classified into four types: A, B, C, and D. Influenza A has subtypes such as H1N1 and H3N2 and is the only type known to cause pandemics. Influenza B is divided into lineages such as B/Yamagata and B/Victoria. Influenza C generally causes mild infections, while Influenza D mainly affects cattle and does not infect humans.
Symptoms usually appear about two days after infection and include fever, dry cough, headache, muscle and joint pain, sore throat, runny nose, and severe fatigue. Most people recover within a week, although the cough may last longer. However, influenza can lead to serious illness or death, especially among high-risk individuals.
Most people with influenza recover without special treatment. People with mild symptoms are advised to stay at home, rest, drink plenty of fluids, manage symptoms such as fever, and seek medical care if the condition worsens.
However, people at high risk or those with severe symptoms should receive antiviral medication as soon as possible. High-risk groups include pregnant women, children under five years, adults aged 65 and above, people with chronic illnesses, and those undergoing treatments such as chemotherapy.
As influenza cases continue to rise during the flu season, health experts emphasize the importance of awareness, early treatment, and preventive measures. Simple actions such as maintaining good hygiene, seeking medical care when symptoms worsen, and protecting vulnerable groups can help reduce the spread of the virus. While influenza may appear like a common illness, its impact can be serious, making public awareness and responsible health practices essential in safeguarding communities.
