HCM CityThe results of viral sequencing of 6 hand, foot and mouth swab samples showed that all were infected with the EV71 genotype B5, in the highly virulent group, causing severe disease and rapid infection.
On the evening of June 5, a representative of the Department of Health of Ho Chi Minh City announced the results of the above virus gene sequencing, performed by a research team at Children's Hospital 6, Hospital for Tropical Diseases and OUCRU (Oxford University Clinical Research Unit).
Six samples were taken from pediatric patients with hand, foot and mouth disease with severe symptoms being treated at Children's Hospital 6, all infected with Enterovirus 1 (EV71), genotype B71.
This genotype was first found in Taiwan (China) in 2007, and appeared in Ho Chi Minh City in 2015 and 2018.
In 2011, EV71 caused an outbreak of hand, foot and mouth disease in Ho Chi Minh City with many severe cases and deaths. At that time, the common gene type was C4. In 2018, the number of severe cases decreased, the main type was B5. According to Dr. Nguyen Minh Tien, deputy director of the City Children's Hospital, the B5 gene is in the highly virulent group, causing severe disease. The spread of B5 is as fast as C4, but the virulence is not as high.
Experts from the Pasteur Institute in Ho Chi Minh City analyzed the epidemiology of hand, foot and mouth disease outbreaks from before 2010 to the present, concluding that outbreaks caused by the C4 gene have a higher rate of complications and a higher number of cases than when B5 was present.
This time, the Center for Disease Control of Ho Chi Minh City (CDC) recorded a rapid increase in the number of children suffering from hand, foot and mouth disease in the city in recent weeks. The number of cases in early June was more than twice as high as two weeks earlier. The re-emergence of the seriously ill EV6 strain makes the situation "really worrying".
The characteristics of EV71 are very rapid spread and severe progression, high fever. Children with hand, foot and mouth disease caused by EV71 virus can have complications such as neurological, cardiovascular, pulmonary edema, shock, heart failure and rapid death.
When the EV71 virus enters the body, they are usually located in the cheek mucosa or intestinal mucosa in the ileum. After 24 hours, the virus reaches the surrounding lymph nodes, from where it enters the bloodstream, causing sepsis within a short time. From sepsis, viruses to oral mucosa and skin. The incubation period usually lasts 3-7 days.
The disease begins with fever, then blisters appear on the oral mucosa (gums, tongue, inside cheeks), erythema on the hands and feet. In case of EV71 virus infection, the disease process is more complicated, especially when the virus damages the central nervous system, it will show typical meningitis.
Type EV71 not only causes hand-foot-and-mouth disease but also has the ability to cause diseases in the central nervous system such as viral meningitis, rarely more severe forms such as encephalitis or polio-like paralysis.
On the same day, the Drug Administration of Vietnam, the Ministry of Health, said that the supply of hand, foot and mouth treatment drugs was interrupted, only a few remaining and planned to be imported in July, requiring Ho Chi Minh City to reserve to cope with the epidemic.
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