Japanese mosquito encephalitis is a severe viral infection that is transmitted through transmission. In this disease, a specific inflammatory process develops in the substance of the brain. This pathology is characterized by severe intoxication syndrome and dangerous neurological disorders. In the vast majority of cases, Japanese mosquito encephalitis has an unfavorable prognosis. However, the literature describes isolated cases in which this condition occurred in mild or abortive forms. Even after recovery, the patient may still have persistent neurological or mental disorders that require further follow-up by appropriate specialists. Other possible complications of Japanese mosquito encephalitis include cerebral edema, pulmonary edema, secondary bacterial flora and even infectious-toxic shock.
Description of the disease
Japanese mosquito encephalitis has been known since the late eighteenth century. One of the largest outbreaks of this infection, which took the lives of nearly eighty percent of sick people, occurred in Japan in the nineteen twenty-fourth year. It was during these years that this disease was most fully described and singled out as an independent nosological unit. In the period from 1933 to 1936, an active study of this pathology, which resulted in the detection of the pathogen.
Despite its name, this disease occurs not only in Japan. The Far East and the Primorsky Krai, Vietnam, India, China and some other countries are also endemic. It has been observed that children under the age of ten have the highest susceptibility to the pathogen. In the event that a pregnant woman is infected, there is a very high probability of spontaneous abortion. According to various data, the mortality rate for such an infection currently ranges from 30 to 70 percent.
Japanese mosquito encephalitis, as we have said, is viral in nature. The causative agent of this disease is arbovirus, which has a high susceptibility to nervous tissue. A distinctive feature of the pathogen is that it is well preserved in the environment. As an example, it will take at least two hours to inactivate the virus by boiling, and it can be stored in disinfectant solutions for up to three days.
This infection is transmitted to humans by mosquito bites. It is worth noting that the bite of an infected mosquito does not always guarantee human infection. Sometimes the pathogen dies immediately at the site of introduction. Whether Japanese mosquito encephalitis develops depends on many factors. First of all, this is the initial state immune system. Virulence of the virus also plays an important role. In classic cases, the pathogen after the bite breaks into the blood, passes through the blood-brain barrier and enters the brain. Actively multiplying in the substance of the brain, the pathogen contributes to damage and death of nerve cells. With the most favorable schedule, the infectious process may become generalized with damage to other internal organs.
It should be noted that such an infection has a clear seasonality. Its main outbreaks occur in August and September, their average duration does not exceed fifty days.
Symptoms of Japanese mosquito encephalitis
Japanese mosquito encephalitis has a short incubation period. On average, from the moment of infection to the appearance of the first symptoms takes from five to sixteen days. In some cases, this disease has a prodromal period, represented by weakness, decreased efficiency, drowsiness, and so on. After some time, the general intoxication syndrome suddenly increases. A sick person complains of a rise in body temperature to thirty-nine degrees and above. The clinical picture is complemented by intense headaches and muscle aches, chills, nausea and vomiting, as well as profuse sweating.
Examination reveals redness of the face. Another specific point is the slowing of heart rate, which is then replaced by their acceleration. On about the third or fourth day, the symptoms that indicate damage to the central nervous system join. The sick person’s consciousness is disturbed, he becomes too excited or inhibited. Often there is delusion. There is pain when trying to bring the chin to the chest, impaired sensitivity. Convulsions, movement disorders and so on may be present.
On average, the general intoxication syndrome lasts from one to one and a half weeks. After that, all the symptoms gradually subside. However, the patient’s condition is completely normalized only after one and a half or two months.
Diagnosis and treatment of infection
Diagnosis of this disease begins with a general examination of the sick person and the collection of complaints. A general blood test and lumbar puncture must be performed, followed by a study of cerebrospinal fluid. Computed tomography or magnetic resonance imaging can be used for differential diagnosis. Detection of the pathogen is carried out by PCR diagnostics or enzyme-linked immunosorbent assay.
Patients with this infection need to be given a specific immunoglobulin. In parallel, detoxification measures are carried out, glucocorticoids and vascular agents are used. If necessary, the sick person is placed on artificial ventilation.
Prevention of the disease
The main method of prevention is protection against mosquito bites with closed clothing, special deterrents and so on. In addition, a specific vaccine against this pathology is currently being developed.
An article about encephalitis
