Unusual weather changes, with rapid temperature fluctuations between sunshine, rain, cold, and heat, impact the immune system, making children more susceptible to illnesses than adults. Below are the causes and manifestations of some commonly encountered illnesses in children during the seasonal transition.
Respiratory Tract Diseases
Respiratory tract diseases take the lead in the list of common ailments in children during seasonal transitions, including nasal inflammation, throat inflammation, tonsillitis, and more severe cases such as bronchitis and pneumonia. These illnesses are primarily caused by viruses and bacteria that spread rapidly when children come into contact with infected individuals or inhale respiratory droplets. When affected, children often show symptoms such as fever, cough, runny nose, sneezing, insomnia, and more.
Flu and Bacterial Infections
Flu and bacterial infections manifest through symptoms such as fever, cough, muscle pain, and fatigue, leaving children drained of energy and in prolonged discomfort. When afflicted, children may experience sudden fever above 38 degrees Celsius, accompanied by chills, shivering, body aches, fatigue, and dry cough. After a while, children may develop a sore throat, stuffy nose, and persistent cough. Although it can self-resolve within 1–2 weeks, the flu still affects health, and in severe cases, dangerous complications may arise.

Gastrointestinal Issues
Weather changes can also impact the quality of children's daily food and nutritional supplements, leading to digestive issues, intestinal infections, acute diarrhea, and food poisoning, commonly seen in children under 5 years old. Among them, acute diarrhea is a serious condition that parents should be attentive to. When experiencing acute diarrhea, children often exhibit symptoms such as diarrhea, vomiting, abdominal pain, and dehydration. This condition is usually caused by viruses, bacteria, and parasites, with Rotavirus, in particular, having the potential to be fatal in children. This virus can persist and remain stable in the environment, on hands, and solid surfaces for many hours, causing illness even after a week of being present in feces.
Hemorrhagic Fever
Hemorrhagic fever is usually caused by the dengue virus transmitted through Aedes mosquitoes. Mosquitoes bite individuals infected with the virus and transmit it to others. Hemorrhagic fever often develops rapidly and can lead to dangerous complications. The disease typically starts with flu-like symptoms such as fever, headache, sore throat, and fatigue. Subsequently, there is bleeding from the nose, red-colored urine, purple bruises on the skin, and bleeding gums.
Hand, Foot, and Mouth Disease
Hand, Foot, and Mouth Disease are often caused by enterovirus group viruses, transmitted through contact with fluids from the nose, throat, saliva, urine, or feces of infected individuals. The disease begins with symptoms such as fever, fatigue, loss of energy, and loss of appetite. Subsequently, red spots appear on the palms, soles, and mouth. The red spots can turn into ulcers. Other symptoms include sore throat, throat pain, vomiting, and diarrhea.

Aside from personal hygiene solutions and maintaining a clean environment, ensuring a balanced, nutrient-rich diet, and complete vaccinations for children, boosting immunity is also a crucial factor parents need to pay special attention to.
According to nutrition experts' recommendations, to ensure the health and robust immunity of children during seasonal transitions, another effective solution is to supplement with Lactoferrin.
Lactoferrin is a type of protein found in mother's milk, helping enhance the child's natural immunity. The role of Lactoferrin is to combat disease-causing agents, inhibit the growth of bacteria and viruses, and prevent the spread of infectious diseases. Additionally, Lactoferrin also has anti-inflammatory and antioxidant properties, reducing bacteria and viruses causing inflammation in the respiratory and intestinal systems, lowering the risk of diseases such as nasal inflammation, throat inflammation, and food poisoning.

Parents can supplement Lactoferrin for children through Morinaga – a trusted milk brand for over 100 years in Japan. Morinaga is also the first milk brand globally to incorporate Lactoferrin into children's milk formula, adhering to the nutritional standards of the World Health Organization (WHO) and the nutritional needs of Vietnamese children, helping children strengthen immunity, maintain healthy digestion, and achieve comprehensive physical and intellectual development.
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