Spring is coming, the temperature is rising, and the hand, foot and mouth disease epidemic season is coming. Recently, China's disease control and some local disease control such as Shaanxi, Guangdong, Guangxi and other countries have issued early warnings.
China's CDC said there is an increased risk of clusters in crowded places such as schools and childcare facilities.
Hand, foot and mouth disease (HFMD) is a common acute infectious disease in children aged 5 years and younger, mainly caused by enteroviruses, with two peaks each year, the peak in spring and summer from April to July, and the peak in autumn from October to November.
The mainland is a country with a high disease burden of hand, foot and mouth disease. In the face of the arrival of the epidemic season, how to prevent and control in advance has attracted attention.
Some experts warn that it is necessary to be vigilant against the new features of atypical hand, foot and mouth disease, which can easily cause missed diagnosis and become an important source of infection.
Be alert for atypical hand, foot and mouth disease
There are dozens of enteroviruses (types) that can cause hand, foot and mouth disease, among which enteroviruses EV-A71 and CVA16 are the most common.
Hand, foot and mouth disease (HFMD) is about 2 to 10 days from infection to symptomatic, with an average of 3 to 5 days, and the clinical manifestations are mostly fever, herpes on the oral mucosa, maculopapular rash and herpes on the hands, feet and buttocks, which can be accompanied by cough, runny nose, loss of appetite and other symptoms. Children usually have mild, self-limited symptoms, and generally have a good prognosis, with a complete recovery in 7 to 10 days. A small number of critically ill patients develop rapid deterioration, neurological complications, and multi-organ failure, which can lead to death in severe cases.
From 2020 to 2022, due to the impact of COVID prevention and control interventions, the number of HFMD cases nationwide decreased significantly. In 2023, after the liberalization of new crown epidemic prevention and control interventions, the epidemic intensity of hand, foot and mouth disease is returning.
In August 2023, Tropical Diseases and Parasitology published an article entitled "Analysis of the Epidemiological Characteristics and Trends of Hand, Foot and Mouth Disease in China after Novel Coronavirus Infection with "Category B and B Tubes", and the corresponding author was Chang Zhaorui, from the Department of Infectious Disease Management of the Chinese Center for Disease Control and Prevention. The study showed that from January to June 2023, 557 940 cases of HFMD were reported nationwide, with a reported incidence rate of 39.68 per 100,000, lower than the average reported incidence rate for the same period from 2017 to 2019 (64.97 per 100,000) and higher than the average reported incidence rate for the same period from 2020 to 2022 (26.37 per 100,000).
"From 2023, the number of hand, foot and mouth cases is higher than the number of the same period in the past three years, and it is difficult to say what the situation will be in 2024. On the whole, the epidemic time of HFMD has not changed much, and it is still necessary to pay attention to the prevention of HFMD when the epidemic season arrives. At present, there is no specific drug for the treatment of hand, foot and mouth disease, and the main treatment is symptomatic. Song Chunlan, director of the emergency medicine department of Henan Provincial Children's Hospital, told the first financial reporter.
Song Chunlan said that at present, it is also necessary to be vigilant against the emergence of new features of atypical hand, foot and mouth disease, which can manifest as atypical rash. The typical rash of hand, foot and mouth disease is maculopapular rash, papules, herpes and so on on the hands, feet, buttocks, oral cavity and other parts, and the atypical rash is usually small, thick, hard, and few, and can also manifest as bullous changes, and is not limited to the hands, feet, and mouth, but can appear in other parts such as the ears, perioral mouth, trunk, and limbs. In the clinical diagnosis of hand, foot and mouth disease, skin rash is the main basis for diagnosis, but when the rash is atypical, it often brings difficulties to the diagnosis, which can easily cause the diagnosis of hand, foot and mouth disease, and become an important source of infection.
Dangers of hand, foot and mouth disease
In 1981, hand, foot and mouth disease began to appear in the mainland. In 2008, HFMD was included in the list of Class C infectious diseases in mainland China. The goal of HFMD prevention and control is to reduce the incidence of disease and reduce severe disease and death.
Song Chunlan said that although the current severe cases of hand, foot and mouth disease are decreasing, but can not be taken lightly, the harm of severe hand, foot and mouth disease is that there may be some serious complications, such as neurogenic pulmonary edema, pulmonary hemorrhage, cardiopulmonary failure, seriously endangering the life safety of children, and even some critical cases of hand, foot and mouth disease, may leave limb movement disorders, dysphagia, abnormal breathing and other serious sequelae.
Cheng Yibing from Henan Provincial Children's Hospital and Li Yu et al. from the Chinese Center for Disease Control and Prevention conducted a hospital-based retrospective cohort study at Henan Provincial Children's Hospital in March 2017 to evaluate the long-term clinical prognosis of 176 cases of HFMD complicated with neurological complications diagnosed with EV-A71 or CVA16 infection from 2010 to 2016, with a median follow-up of 4.3 years (range: 1.4-8.3). The study suggests that children with HFMD with neurological complications may have abnormalities in the nervous system, motor, language, cognition, adaptive behavior, and respiratory function, and that long-term follow-up of children's neurodevelopment and respiratory function is necessary.
Prevention of hand, foot and mouth disease
Song Chunlan said that to prevent the occurrence of severe HFMD, it is necessary to identify it at an early stage and take intervention measures. In the face of the arrival of the epidemic season, children should avoid going to crowded places as much as possible, and if they do, try to wear masks and wash their hands frequently. However, the most effective way to prevent HFMD is vaccination. EV-A71 infection is the leading cause of severe disease and mortality from hand, foot and mouth disease. Since the end of December 2015, three EV-A71 vaccines have been approved for marketing in China. The EV-A71 vaccine can be used to prevent HFMD caused by EV-A71 infection in children aged 6 months to 5 years. Although the EV-A71 vaccine is only aimed at preventing HFMD caused by enterovirus EV-A71, it can reduce the symptoms of HFMD to a certain extent, reducing severe disease and death.
Studies have shown that there is a need to strengthen pathogen surveillance for severe hand, foot and mouth disease.
A study entitled "Pathogen Spectrum and CV-A6 Gene Characteristics Analysis of 882 Cases of Severe Hand, Foot and Mouth Disease in 2012⁃2023" published in Acta Virologica Sinica in March 2024 was written by Daniel Zhang, Institute of Viral Disease Prevention and Control, Chinese Center for Disease Control and Prevention.
The results of the study showed that the number of cases of severe hand, foot and mouth disease began to decline year by year after 2016. On the one hand, the reason is that the inactivated EV-A71 vaccine began to be promoted and applied after its marketing in 2016, which reduced the number of severe cases of EV-A71-related hand, foot and mouth disease, and before that, EV-A71 had been the most important pathogen causing severe hand, foot and mouth disease, accounting for 50% of the pathogen spectrum On the other hand, the intervention measures are improving year by year, health education related to the prevention and control of hand, foot and mouth disease can reduce the incidence of hand, foot and mouth disease, thereby reducing the number of severe hand, foot and mouth disease cases, especially during the new crown epidemic, the number of severe hand, foot and mouth disease cases has decreased significantly, and home isolation measures should play an important role.
However, this study also suggests that after 2018, the proportion of EV-A71 in the pathogen spectrum of severe hand-foot-and-mouth disease has decreased significantly, and the proportion of other enteroviruses represented by CVA6 and CVA10 has increased significantly, gradually replacing EV-A71 and CVA16 as the main pathogens causing severe hand, foot and mouth disease, and CVA6 infection will also cause central nervous system symptoms such as aseptic meningitis, which deserves attention.
(This article is from Yicai)