Hand-foot-mouth disease (HFMD) is a common infectious disease caused by a variety of enteroviruses, mainly in infants and children. Most patients have mild symptoms and are characterized by fever and a rash or herpes on the hands, feet, and mouth. A small number of patients can be complicated by aseptic meningitis, encephalitis, acute flaccid paralysis, respiratory tract infection and myocarditis, etc. Individual children with severe disease progress rapidly and are prone to death. Adolescent children and adults do not develop disease after infection, but are able to transmit the virus. The enteroviruses that cause HFMD include enterovirus 71 (EV71) and some serotypes of group A coxsackieviruses (CoxA) and echoviruses (Echo), and EV71 infection causes a greater proportion of severe cases. Enteroviruses are highly contagious and can easily cause outbreaks or epidemics. To guide the prevention and control of hand, foot and mouth disease around the world, the development of this guide.
I. Purpose
(a) to guide medical institutions, disease prevention and control agencies to carry out epidemic reporting and monitoring of enteroviral diseases.
(B) guide disease prevention and control institutions to carry out epidemiological investigations and laboratory tests.
(C) to guide disease prevention and control institutions, medical institutions to carry out public prevention and emergency response to epidemics.
Second, the pathogenesis
Hand, foot and mouth disease is mainly caused by small RNA virus family, enterovirus genus Coxasckie virus (Coxasckie virus) A group 16, 4, 5, 7, 9, 10 types, B group 2, 5, 13 types; Echovirus (ECHO viruses) and enterovirus 71 (EV71), of which EV71 and Cox Al6 type is the most common.
Enteroviruses are suitable for survival and transmission in wet and hot environments, and are insensitive to ether, dechlorinated bile salts, etc. 75% alcohol and 5% lysol cannot inactivate them, but they are sensitive to UV light and drying. Various oxidizing agents (potassium permanganate, bleach, etc.), formaldehyde, iodine are able to inactivate the virus. The virus can be inactivated rapidly at 50°C, but 1 mol concentration of divalent cation environment can improve the resistance of the virus to heat inactivation, the virus can survive for 1 year at 4°C, and can be stored for a long time at -20°C. The virus can survive for a long time in the external environment.
III. Epidemiology
(I) Epidemiological overview
Hand, foot and mouth disease is a global infectious disease, the epidemic of this disease has been reported in most parts of the world. 1957 New Zealand first reported the disease. 1958 isolated coxsackie virus, 1959 proposed the name of hand, foot and mouth disease. The causative agent of HFMD identified early on was mainly Cox A16, and EV71 was first identified in the United States in 1969. Since then, EV71 infection has alternated with Cox A16 infection as the main pathogen of HFMD.
In the mid-1970s, Bulgaria and Hungary had successive outbreaks of EV71 epidemics with the central nervous system as the main clinical feature, and 750 cases were reported in Bulgaria in 1975, of which 149 caused paralysis and 44 died. 1994, an outbreak of HFMD caused by Cox A16 occurred in the UK, and most of the patients were infants and children aged 1-4 years, and most of them had mild symptoms. Epidemiological data from the UK since 1963 show that the interval between HFMD epidemics is 2-3 years. in the late 1990s, EV71 became endemic in East Asia. in 1997, an epidemic of HFMD caused mainly by EV71 occurred in Malaysia, with a total of 2,628 cases from April to August and 29 deaths from April to June.
In China, the disease was first reported in Shanghai in 1981, and since then, it has been reported in more than 10 provinces, including Beijing, Hebei, Tianjin, Fujian, Jilin, Shandong, Hubei, Qinghai, and Guangdong. 1983 saw an outbreak of HFMD caused by Cox A16 in Tianjin, with more than 7,000 cases occurring between May and October. After 2 years of low-level dissemination, another outbreak occurred in 1986. EV71 was isolated from HFMD patients at the Wuhan Institute of Virus Research in 1995 and also from specimens of HFMD patients at the Shenzhen Health and Prevention Station in 1998.
In 1998, an epidemic of hand, foot, and mouth disease and herpes pharyngitis caused by EV71 infection occurred in Taiwan, China, and a total of 129,106 cases were reported from surveillance sentinels. A total of 405 severe cases and 78 deaths occurred that year, mostly in young children under 5 years of age. Complications of severe cases included encephalitis, aseptic meningitis, pulmonary edema or pulmonary hemorrhage, acute flaccid paralysis, and myocarditis.
There is no obvious regional prevalence of HFMD. It can occur throughout the year, with summer and fall being the most common and winter onset being less common. During the epidemic, collective infections in kindergartens and child care centers and family clusters can occur. Enterovirus is highly contagious, the proportion of hidden infection is large, the transmission route is complex, the speed of transmission, in a short period of time can cause a large range of epidemic, the epidemic control is difficult.
(B) Sources of infection and transmission routes
People are the only host of enterovirus, patients and recessive infections are the infectious source of the disease. The enterovirus is mainly transmitted by fecal-oral and/or respiratory droplets, but can also be infected by contact with the patient’s skin and mucosal vesicles. It is not known whether it can be transmitted through water or food. The virus can be detected in the pharynx and feces of infected patients several days before the onset of the disease, and is usually most contagious within a week after the onset of the disease.
The disease can be transmitted by the patient’s feces, herpes fluid, respiratory secretions and their contaminated hands, towels, handkerchiefs, dental cups, toys, eating utensils, milk utensils, bedding, underwear and medical instruments.
Susceptibility
People are generally susceptible to enteroviruses, and specific immunity can be acquired after both dominant and latent infections, the duration of which is unclear. There is no cross-immunity between virus types. Infection can occur in all age groups, but the incidence is highest in the ≤3-year-old age group.
IV. Case definition
(A) Clinical diagnosis of cases
Acute onset, fever, maculopapular and herpetic rash on the palms of the hands or feet, and a rash on the buttocks or knees. The rash is surrounded by an inflammatory redness with little fluid in the blisters; scattered herpes appear in the oral mucosa and are painful. Some children may have cough, runny nose, loss of appetite, nausea, vomiting and headache.
Severe cases: 1. patients with clinical manifestations of HFMD accompanied by myoclonus, or encephalitis, acute delayed paralysis, cardiopulmonary failure, pulmonary edema, etc. 2. infants and children in HFMD endemic areas without typical manifestations of HFMD but with fever accompanied by myoclonus, or encephalitis, acute delayed paralysis, cardiopulmonary failure, pulmonary edema, etc.
(B) Laboratory diagnosed cases
A clinical diagnosis case is a laboratory diagnosis case if it meets one of the following conditions
1. Virus isolation
Enterovirus is isolated from throat swab or throat wash, stool or anal swab, cerebrospinal fluid or herpes fluid, and tissue specimens of brain, lung, spleen, lymph nodes, etc.
2. Serological tests
The patient’s serum is positive for specific IgM antibodies, or there is a 4-fold or higher increase in serum IgG antibodies during the acute and recovery periods.
3. Nucleic acid test
Detection of pathogenic nucleic acid in patient’s serum, cerebrospinal fluid, pharyngeal swab or throat wash, stool or anal swab, cerebrospinal fluid or herpes fluid, and tissue specimens such as brain, lung, spleen, lymph nodes, etc.
V. Outbreak report
(a) Since May 2, 2008, hand, foot and mouth disease into the management of category C infectious diseases. Medical institutions at all levels should report cases of HFMD that meet the above case definitions in accordance with the relevant provisions of the “Prevention and Control of Infectious Diseases Law of the People’s Republic of China” and the “Infectious Disease Information Reporting Management Code”.
(II) Reporting content and methods
When a patient with HFMD is found, the disease should be reported in the column of “Other infectious diseases under statutory control and key surveillance” in the “Infectious Disease Report Card of the People’s Republic of China”. Medical institutions that implement direct network reporting should do so within 24 hours. Medical institutions without direct network reporting should send out the infectious disease report card within 24 hours. Reported cases are divided into two categories: “clinical diagnosis” and “laboratory diagnosis”. For laboratory diagnosed cases, the specific type of enterovirus should be indicated in the “Remarks” column of the report card, and for severe cases, “severe” should also be indicated in the “Remarks”.
(C) local areas or collective units in the event of an epidemic or outbreak, in accordance with the “Emergency Regulations for Public Health Emergencies”, “National Emergency Plan for Public Health Emergencies”, “Public Health Emergencies and Infectious Disease Surveillance Information Reporting Measures” and related provisions, timely information reporting of public health emergencies.
(D) Report information analysis and feedback
Disease prevention and control agencies at all levels should review the information reported on the epidemic at each level. County and district-level disease prevention and control agencies should browse and analyze surveillance data on a daily basis, and if abnormal elevations or cases are found to be aggregated and distributed or fatal, they should promptly verify and report to the health administrative departments at the same level and to higher-level disease prevention and control agencies. Disease prevention and control agencies at all levels should provide timely feedback to lower-level disease control agencies and medical institutions on the analysis of the epidemic.
VI. Epidemiological investigation
Epidemiological investigation should be organized when the number of reported cases of HFMD is found to be significantly increased, the cases are aggregated and distributed, the proportion of severe cases is large or there are fatal cases. The main purpose of the survey: first, to collect relevant specimens, laboratory testing, clarify the pathogen and typing identification; second, to collect clinical information to understand the pathogenicity of different types of enterovirus, virulence, the clinical type of disease caused and treatment; third, to clarify the epidemic / outbreak of the mode of transmission and risk factors of infection, in order to develop targeted preventive and control measures; fourth, to evaluate the effectiveness of different prevention and control strategies and Fourth, to evaluate the effectiveness of different prevention and control strategies and measures. Epidemiological survey programs and questionnaires should be designed specifically for different purposes of investigation.
Seven, laboratory testing
In the high season of HFMD, provincial CDCs should organize laboratory surveillance of HFMD cases. Occurrence of the disease epidemic provinces at least 5-10 cases of patients per week to collect specimens for testing. See Annex 1 and Annex 2 for specimen collection and preservation techniques and specimen delivery forms, and Annex 3 for specimen testing methods. If there is an outbreak, specimens from some cases should be collected for pathogen testing. Areas without testing capabilities may send specimens to a qualified CDC laboratory for testing. When collecting specimens, attention should be paid to the collection of information about the case, fill out the case investigation form see Annex 4.
VIII. Prevention and control measures
Hand, foot and mouth disease transmission channels, infants and children are generally susceptible. Good hygiene in children’s personal, family and childcare institutions is the key to prevent the infection of this disease.
(A) Personal preventive measures
1. wash children’s hands with soap or hand sanitizer before and after meals and after going out, do not allow children to drink raw water or eat cold food, and avoid contact with sick children.
2. caregivers should wash their hands before touching children and after changing diapers and handling feces for young children, and dispose of dirt properly.
3. bottles and pacifiers used by infants and children should be washed well before and after use.
4. children should not be taken to public places with poor air circulation during the epidemic period, and attention should be paid to maintaining household sanitation, frequent ventilation of the living room, and regular drying of clothes and blankets.
5. children with symptoms should go to medical institutions promptly. Children treated at home should not come into contact with other children, parents should dry or disinfect the affected children’s clothes and disinfect the children’s feces in a timely manner; children with minor illnesses do not need to be hospitalized, but should be treated and rested at home to reduce cross-infection.
(B) Preventive and control measures for collective units such as child care institutions and elementary school
1. during the epidemic season, classrooms and dormitories and other places should be well ventilated.
2. daily cleaning and disinfection of toys, personal hygiene utensils, tableware and other items
3. staff should wear gloves when cleaning or disinfecting work (especially cleaning toilets). Washing hands immediately after cleaning work.
4. wipe and disinfect door handles, stair railings, table tops and other surfaces daily.
5. educate and instruct children to develop the habit of proper hand washing.
6. to conduct daily morning check-ups and take measures to send the child to the hospital and rest at home when suspicious children are found; to disinfect the objects used by the child immediately.
7. promptly report to the health and education departments when the number of affected children increases. Depending on the need for epidemic control when the education and health departments may decide to take measures to close child care institutions or elementary school.
(iii) Preventive and control measures for medical institutions
1. during the disease epidemic, hospitals should implement pre-screening and triage, and designate consultation rooms (desks) to receive suspected HFMD patients, direct children with fever and rash to special consultation rooms (desks), increase the frequency of cleaning and disinfection in areas such as waiting and consultation, and use wet cleaning when cleaning indoors
2. medical staff should carefully wash their hands or disinfect them after treating and caring for each patient.
3. non-disposable instruments and objects used in the process of treating and caring for patients should be wiped and disinfected.
4. no other non-enterovirus infected children should be admitted in the same ward. Children with serious illnesses should be treated in separate isolation.
5. facilities and objects such as beds and tables and chairs used by hospitalized children must be disinfected before further use
6. respiratory secretions and feces of children and their contaminated items should be disinfected
7. medical institutions shall immediately report to the local health administrative department and the CDC when they find an increase in the number of patients with HFMD or deaths related to enterovirus infection.