During the first 2-3 days, Japanese encephalitis may only cause fever, headache, and fatigue, but then convulsions, confusion, coma, or respiratory failure.
In August, the Central Tropical Diseases Hospital received a 9-year-old boy in Lao Cai who was in a coma, respiratory failure and quadriplegia due to Japanese encephalitis. Two days before that, the child started to have a fever and headache. He took fever-reducing medicine but did not improve. The headache gradually increases, accompanied by nausea, vomiting and the child falls into a coma. After two weeks of treatment, the patient still needs to be monitored for neurological complications.
Previously, Bach Mai Hospital also treated a 7-month-old girl with Japanese encephalitis. The child was hospitalized after high fever and prolonged full-body convulsions. He had to be treated intensively for 24 days to stabilize and be discharged. The two cases show that the disease can appear in many age groups and progress seriously after initial symptoms that are difficult to distinguish.
Dr. Le Thi Truc Phuong, Medical Specialist, VNVC Vaccination System, said that Japanese encephalitis is an acute disease caused by the virus of the same name that attacks the central nervous system. During the first 2-3 days, patients often have fever, headache, fatigue, nausea or vomiting. These symptoms are easily confused with many common infections.
When the disease becomes severe, children may have increased headaches, vomiting a lot, lethargy, difficulty waking up, behavioral changes, confusion, seizures or weakness in the limbs. Symptoms such as coma, weakness and difficulty breathing show that the nervous system has been seriously damaged. For young children whose symptoms cannot be described, parents need to pay attention to unusual crying, not feeding or not eating, sleeping a lot and reacting poorly.
According to Dr. Phuong, after entering the body, the virus can reach the central nervous system, causing inflammation and brain edema. Depending on the area of the brain affected, the patient may have consciousness disorders, seizures, impaired movement or respiratory disorders. There is currently no specific treatment for Japanese encephalitis, treatment is mainly aimed at supporting and controlling complications.
Just because the patient gets through the acute stage does not mean they will fully recover. A study evaluating 360 Japanese encephalitis pediatric patients treated at the National Children's Hospital in the period 2017-2023 recorded that 42.2% of cases had long-term sequelae or died despite being saved from the acute illness. Of these, 29 children died, 41 children had severe sequelae, 56 children had moderate sequelae and 23 children had mild sequelae.
Neurological - motor sequelae are the most common form. Brain damage can also affect cognition, language, behavior and ability to function in the long term. The need for mechanical ventilation, tracheostomy and hospital stay of more than two weeks are factors related to the risk of long-term sequelae or death in the pediatric patient group studied.
Dr. Phuong recommends taking children to a medical facility when they have a high fever that is difficult to reduce, accompanied by severe headaches, continuous vomiting, lethargy, behavioral changes, convulsions, weakness of limbs or disturbance of consciousness. Parents should not continue self-monitoring at home when neurological manifestations appear or symptoms increase rapidly.
Japanese encephalitis virus is maintained in nature mainly in wild birds and pigs. Culex mosquitoes suck the blood of animals carrying the virus and then transmit it to humans through their bites. This species of mosquito often lives in areas with fields, ponds or barns, but the risk of mosquito bites is not limited to rural areas.
Because the mosquito vector is difficult to control and there is no specific treatment for the disease, proactive disease prevention plays an important role. Parents need to check their child's vaccination history and complete Japanese encephalitis vaccinations according to the type of vaccine used, age and instructions from medical staff.
In Vietnam, the Japanese encephalitis vaccine has been included in the Expanded Program on Immunization since 1997. With the Jevax vaccine, after the three basic doses, children need booster vaccinations according to the recommended schedule to maintain immunity. In addition, vaccination services have vaccines with different age indications and vaccination schedules and some do not require booster vaccinations.
If you do not remember the type of vaccine, the number of injections or the time of the last vaccination, parents can go to the vaccination facility to look up and get advice based on vaccination history. Do not second-guess the schedule or skip the next shot because you think your child was vaccinated when they were young. Dr. Phuong informed that VNVC centers nationwide are currently looking up and issuing vaccination confirmations for children to complete their school admission documents according to Decree 165 of the Government.
Besides vaccination, families need to limit the risk of children being bitten by mosquitoes by sleeping under mosquito nets, using appropriate mosquito repellent measures, cleaning the environment and eliminating places with stagnant water where mosquitoes can breed.
