The season for HFMD is now at its peak, are you prepared as a parent?
laurasanders (jennyliu1989/translation) Hand, foot and mouth disease (HFMD) is a common childhood disease caused by a small number of different viruses that can develop in cattle, sheep and pigs. Because HFMD spreads easily and quickly in daycare nurseries, playgrounds, and pools, most children are susceptible to contracting the disease before the age of 5.
HFMD is an acute infectious disease caused by enteroviruses (Coxsackie A group 16 (CoxA16) and enterovirus 71 (EV71) are common), mostly occurring in preschool children, with the highest incidence especially in the under-3 age group. The disease is mainly transmitted through the gastrointestinal tract, respiratory tract and close contact, with both patients and latent infections as the source of infection. The main symptoms are maculopapular rash and herpes on hands, feet and oral cavity, with oral pain, anorexia, low fever, small herpes or ulcers on hands, feet and oral cavity, etc. Most children heal spontaneously within a week or so. Brainstem encephalitis and neurogenic pulmonary edema. The main causes of death are brainstem encephalitis and neurogenic pulmonary edema.
Epidemiological profile
HFMD is a global infectious disease, and epidemics of the disease have been reported in most parts of the world. In China, the disease was first seen in Shanghai in 1981, and has since been reported in more than a dozen provinces and cities, including Beijing, Hebei, Tianjin, and Fujian.
Source of infection
The source of infection for HFMD is the patient and the latent infected person. During the epidemic, patients are the main source of infection. Patients excrete virus from the pharynx in 1 to 2 weeks after onset, and from the feces in about 3 to 5 weeks, and the herpes fluid contains a large amount of virus, which spills out when it breaks. Herpes fluid contains a large amount of virus, and the virus is released when it breaks down. The main source of infection in the inter-epidemic and epidemic period is the carrier and the lightly disseminated cases.
Transmission route
HFMD is mainly transmitted through close contact between people. The virus in the throat secretions and saliva of patients can be transmitted by airborne droplets. It can be spread by daily contact with saliva, herpes fluid, feces-contaminated hands, towels, handkerchiefs, tooth cups, toys, eating utensils, milk utensils, bedding, underwear, etc. It can also be spread by mouth. Contact with water contaminated with the virus can also be transmitted orally and often causes epidemics. Cross-infection in outpatient clinics and poor disinfection of oral instruments can also cause transmission.
Susceptible population
People are generally susceptible to the enterovirus that causes HFMD, and can acquire immunity after being affected, and all age groups can be infected with the disease, but the ratio of recessive virus infection to dominant infection is 100:1, and most adults have acquired the corresponding antibodies through recessive infection, therefore, patients with HFMD are mainly preschool children, especially the highest incidence in the ≤3-year-old age group, and within 4 years of age account for 85% to 9 5% of the incidence. According to foreign observations, epidemics occur every 2 to 3 years in the population, mainly during the birth of newborns during non-epidemic periods, when susceptible individuals gradually accumulate and reach a certain number, providing prerequisites for new epidemics. After the 1983 epidemic in Tianjin, China, epidemic cases continued to be disseminated, and the epidemic occurred again in 1986, and both times were caused by Cox Al6.
Epidemic pattern
HFMD is extremely widespread and not strictly regional. The disease can occur in all seasons, with summer and autumn being the most common and winter being the least common. The disease is often scattered after an epidemic outbreak, and kindergartens and nurseries are susceptible to collective infections during the epidemic. Families also have clusters of this disease. Cross-infection in hospital outpatient clinics and lax sterilization of oral instruments can also cause transmission. In the two large epidemics in Tianjin, the incidence of the disease was significantly higher in children in nursery units than in children living in the diaspora. Families often have one case in a family; in family outbreaks, more than one family or all children and adults are infected. The disease is highly contagious, with complex transmission routes, high epidemic intensity and rapid spread, and can cause pandemics in a short period of time.
Pathogenesis
There are many viruses that cause HFMD, mainly coxsackieviruses, echoviruses and new enteroviruses of the genus Enterovirus in the family of small RNA viruses. 16, 4, 5, 7, 9, 10 types of CoxA group, 2, 5, 13 types of CoxB group, and EV 71 are the more common pathogens of HFMD, the most common being Cox Al6 and EV 71 types, with some reports of echovirus and EV 71 types. Some report that Echovirus and some types of Cox group B can also cause, but further confirmation has not been obtained.
Data indicate that the pathogens of HFMD have undergone a large change. Enterovirus is suitable for survival and transmission in wet and hot environments, and is resistant to drugs. 75% alcohol and 5% lysol have no effect on enterovirus, and are not sensitive to ether and dechlorinated bile salts. However, it is sensitive to ultraviolet light and drying, and can be inactivated by various oxidizing agents (potassium permanganate, bleach, etc.), formaldehyde, and iodine. The virus can be inactivated rapidly at 50 ℃, 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 ℃, and can be stored for a long time at – 20 ℃, and the virus can survive for a long time in the external environment.
Clinical manifestations and pathological clinical manifestations
Herpes on the palms of the feet due to hand, foot and mouth disease
HFMD has common features of enteroviral infections. It can occur from the most common asymptomatic or only mild discomfort to severe complications or even death. The incubation period is usually 3-7 days, with no obvious prodromal symptoms, and most patients have a sudden onset of disease. About half of the patients have fever, mostly around 38°C, 1 to 2 days before or at the same time as the onset of the disease. It mainly invades four parts of the body: hands, feet, mouth and buttocks (tetralogy of Fallot); scattered herpes, the size of a grain of rice and painful, appear on the oral mucosa; rice-grain sized herpes appear on the palms of the hands or feet, and the buttocks or knees may occasionally be involved by clinical features. Some patients initially have mild upper sensory symptoms, such as cough, runny nose, nausea, vomiting, etc. The child salivates and refuses to eat due to painful oral ulcers. Oral mucosal rash appears relatively early, initially as corn-like papules or blisters surrounded by a red halo, mainly on the tongue and cheeks, and often on the lateral side of the lips and teeth. The rash is not itchy, and the papules turn from red to dark in about 5 days and then fade; the herpes is round or oval flattened and raised, with cloudy liquid inside, with the same length and diameter as the skin line, such as the size of a soybean, generally without pain and itchiness, and leaves no trace after healing. Hand, foot and mouth lesions may not all appear in the same patient. The blisters and rash usually resolve within a week.
Comorbidities
HFMD manifests mainly on the skin and mouth, but the virus can invade vital organs such as the heart, brain, and kidneys. Clinical monitoring of patients should be strengthened during epidemics of this disease. If high fever and unexplained increase in white blood cells are present and no other foci of infection can be detected, we should be alert for the development of fulminant myocarditis. In recent years, EV 71 has been found to have a greater chance of aseptic meningitis than Cox Al6-induced HFMD, with symptoms presenting as fever, headache, stiff neck, vomiting, easy irritability, and restless sleep; non-specific erythematous papules or even punctate bleeding spots may occasionally be found on the body. Central nervous system symptoms are mostly seen in children less than 2 years old.
Diagnosis and differential diagnosis Main diagnostic bases
Epidemiological data, clinical manifestations, laboratory tests, and pathogenic tests are required to confirm the diagnosis.
Prevalence in summer and autumn.
Children are the main target of the disease, and it often occurs in places where infants and children gather and is epidemic.
The main clinical manifestations are initial fever, mild elevation of total white blood cell count, followed by maculopapular rash and herpes-like damage to the mucous membranes and skin of the mouth, hands and feet.
The course of the disease is relatively short, mostly healing within a week.
Laboratory diagnosis
A clinical diagnosis is made when one of the following conditions is met
Virus isolation Enterovirus is isolated from throat swab or throat wash, stool or anal swab, cerebrospinal fluid or herpes fluid, and tissue specimens such as brain, lung, spleen, and lymph nodes.
Serologic tests Patients with positive serum specific IgM antibodies, or a 4-fold or greater increase in serum IgG antibodies during the acute and recovery phases.
Nucleic acid test Pathogenic nucleic acid is detected 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.
Difference between hand, foot and mouth disease and foot-and-mouth disease
Although foot-and-mouth disease and hand-foot-and-mouth disease are similar in that they are both located in the mouth, between the fingers, and at the toes, they have different symptoms and signs.
The pathogen of foot-and-mouth disease is the foot-and-mouth disease virus, which is a zoonotic pathogen. Foot-and-mouth disease virus only causes the occurrence of even-hoofed animals such as cattle, sheep, pigs, deer and camels, which become infectious sources of foot-and-mouth disease in humans. Only if the veterinary disease occurs first is it possible to make people sick. Foot-and-mouth disease is contracted through contact with ulcers on the mouth and crown of the hoof of sick animals and through the mucous membrane of the skin; occasionally, it is also contracted by eating milk contaminated with the virus and not heated. Therefore, foot-and-mouth disease in humans is an extremely sporadic occurrence. FMD in humans is determined by contact with diseased animals, and the age of the population with the disease is widespread, while HFMD is mainly an infectious disease in young children and children, with the majority of children under 3 years old. The two main features of FMD are fever and other symptoms of systemic toxicity and local herpes damage. In contrast, most cases of HFMD have no fever or low fever, only respiratory infections and oral mucosal herpes and papules on the fingers, feet, buttocks and knees. Foot-and-mouth disease requires the occurrence or prevalence of foot-and-mouth disease in local livestock and the opportunity for contact with diseased animals, or drinking contaminated and unheated milk from diseased animals, and other infectious relationships. Hand, foot and mouth disease, the infectiousness of the affected children is obvious, epidemic transmission, and there are differences in clinical manifestations. Foot-and-mouth disease, hand-foot-mouth disease can be diagnosed on a clinical basis, and if necessary, isolate the virus to make a pathogenic confirmation of the diagnosis.
Outbreak report
Since May 2, 2008, hand, foot and mouth disease into the management of category C infectious diseases. Medical institutions of all levels and types are required to report cases of HFMD that meet the above case definitions in accordance with the relevant provisions of the “Law of the People’s Republic of China on the Prevention and Control of Statutory Infectious Diseases” and the “Infectious Disease Information Reporting Management Code”.
Treatment
The prognosis of this disease is generally good if there are no complications, and it is mostly cured within a week. The principle of treatment is mainly symptomatic. Antiviral drugs and herbal medicines to clear fever and detoxify the body and vitamin B and vitamin C can be given. Patients with comorbidities can be injected with propyl globulin. During the period of illness, the care of the child should be strengthened and oral hygiene should be done. Before and after eating, saline or warm water can be used to rinse the mouth, and non-irritating food such as liquid and semi-liquid is appropriate. Hand, foot and mouth disease can be combined with myocarditis, encephalitis, meningitis, chorioretinitis, etc., so we should strengthen the observation and not take it lightly.
Prevention
HFMD is transmitted in many ways, and infants and children are generally susceptible. Good hygiene for children, families and childcare institutions is the key to prevent infection.
Personal precautions
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.
Caregivers should wash their hands before touching children, after changing diapers for young children and after handling feces, and dispose of dirt properly.
Bottles and pacifiers used by infants and children should be washed well before and after use.
During the epidemic period, children should not be taken to public places where people gather and air circulation is poor, and attention should be paid to maintaining household sanitation, frequent ventilation of the living room and regular drying of clothes and blankets.
Children who develop 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 affected children’s feces in a timely manner; children with minor illnesses do not need to be hospitalized, it is advisable to treat and rest at home to reduce cross-infection.
Preventive and control measures for collective units
(a) During the epidemic season of the disease, classrooms and dormitories and other places should be well ventilated.
Daily cleaning and disinfection of toys, personal hygiene utensils, tableware and other items.
Staff should wear gloves when performing cleaning or disinfection work (especially cleaning toilets). Washing hands immediately after cleaning work.
Daily wiping and disinfection of object surfaces such as door handles, stair handrails, and table tops.
Educate and instruct children to develop the habit of proper hand washing.
Conducting daily morning checkups and taking measures to promptly send the child to the hospital and rest at home when suspicious children are found; disinfecting objects used by the child immediately.
When the number of affected children increases, promptly report to the health and education departments. 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.
Preventive and control measures for medical institutions
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), waiting and consultation areas should increase the frequency of cleaning and disinfection, and wet cleaning should be used for indoor cleaning.
Medical personnel should wash their hands carefully or disinfect them after treating and caring for each patient.
Non-disposable instruments and items used in the process of treating and caring for patients should be wiped and disinfected
No other non-enterovirus infected children should be admitted in the same ward. Children with serious illnesses should be treated in separate isolation
Facilities and items such as beds and tables and chairs used by hospitalized children must be disinfected before continued use
Respiratory secretions and feces of children and their contaminated items should be disinfected
Medical institutions are required to immediately report to the local health administration and CDC when they find an increase in HFMD patients or deaths related to enterovirus infections.
Seven facts and a puzzle about hand, foot and mouth disease
Since HFMD is caused by a virus, there is not a lot to do except fight the virus. Here are 7 facts and 1 puzzle about HFMD.
1. The depressing thing is that you may contract HFMD more than once. The main culprit of HFMD is coxsackievirus A16 or enterovirus 71. but other viruses may also cause HFMD. Coxsackievirus A16 causes high fever and a specific rash that can cause serious damage to children’s bodies. Eileen Schneider, a medical epidemiologist at the CDC in Atlanta, said, “During the coxsackievirus A16 outbreak, we saw more children with blisters than we thought.” Variant subgroups of enterovirus 71 were found in mainland China and Hong Kong. The diversity of viruses means that having had HFMD once does not make you immune for life. Depending on the similarity of the viruses, earlier exposures may help the body beat the new virus, but this is not a certainty.
2. Like many other viruses, enteroviruses prefer a warm environment. This means that HFMD is more common in the south. In cooler places, the incidence of HFMD shows seasonal fluctuations, peaking in the summer and during early fall.
3. A HFMD vaccine against enterovirus 71 is under development. In studies of large numbers of Chinese children, inactivated viruses have shown strong protective efficacy. However, the vaccine does not combat HFMD caused by coxsackievirus.
4. These highly infectious diseases can be transmitted through secretions, such as saliva and feces. Tom Solomon of the University of Liverpool in the United Kingdom believes that these body secretions have many viruses because they proliferate in the mouth, throat, and intestines. There are also many virus particles in the blisters, but the blister exudate is not the primary means of transmission.
5. After contracting HFMD, do not be alarmed if your fingernails fall off, as this is a possible scenario. We have encountered several cases of patients with nail loss, and the nails will be replaced with new ones.
6.HFMD virus can exist in the body for a long time. Coxsackie A16 can be present in the stool of sick children for up to six weeks, and enterovirus 71 may persist for up to 10 weeks. Infection decreases during this time, but there is debate about how long children should be isolated. Different doctors in the United States have different opinions. Some doctors say two days is enough to return to social life. Some pediatricians, however, say that children need to wait until all the blisters have subsided in order to return to the population. Still other doctors say that once the fever is gone the contagion is gone. According to Schneider, there is no magic number that accurately describes how many days it takes for a person to be safe or to have a problem. The most important thing to do is to carefully observe each child’s symptoms and then judge.
7. If you ever drive up to 87th North in New York City, chances are you’ll have a brush with the coxsackie virus, and fecal samples containing the newly discovered coxsackie disease are being stored in upstate New York City.
Finally, there is a mystery: The reason why the virus normally acts on the hands, feet and mouth, producing a herpes in each of those 3 areas, but nothing else (with herpes) remains a mystery, at least to the general public, virus experts and many pediatricians. I don’t think anyone is sure of the cause,” Solomon said. Injuries to the mouth and throat can allow the virus to spread efficiently through coughing, but blisters on the hands and feet may just be a place for the virus to reside.”
For HFMD, some cases are mild (presenting only as herpes of the hands, feet and mouth) and self-limiting, but others can present with severe clinical manifestations of neurological symptoms such as meningitis, encephalitis and polio-like paralysis. Even death. EV71 infection is the main cause of severe cases and deaths, but the main cause of the large outbreaks seen in China in 2008 and 2009 was both EV71 and coxsackievirus A16.