benefits children and presenting Pediatric multisystem inflammatory syndromes (PIMS), were admitted to hospital. Cases were first reported to health authorities by the United Kingdom. Other countries have made the same observation, such as Italy and Belgium. In France, the Necker hospital in Paris, reported 125 cases of children hospitalized in April 2020. To date, on May 28, 2021, 563 cases have been identified. What are the symptoms ? What is the link between PIMS and Covid-19? What are the risks for children?

Definition and symptoms of Kawasaki disease

Kawasaki’s maladie is a rare disease. It was discovered in Japan, by pediatric Dr. Tomisaku Kawasaki in 1967, according to l’association vascularites. This pathology is one of the orphan diseases. We speak of orphan disease when the prevalence is less than 5 cases per 10 inhabitants. Kawasaki’s maladie is characterized by acute systemic vasculitis; it is an inflammation of the walls of the blood vessels. It is manifested by a rather high fever, which persists for at least 5 days. It is poorly tolerated by the child. To say that a child has Kawasaki’s maladie, the fever must be associated with at least 4 of the following symptoms : 

• Swelling of the lymph nodes; 
• Skin rash ;
• Conjunctivitis; 
• Raspberry tongue and cracked lips; 
• Scalding of the ends of the skin accompanied by redness and edema. 

In most cases, the disease is mild and children do not have all of the symptoms; this is called an atypical or incomplete disease. The child needs to be followed and supervised by the medical profession. He is given treatment and his body generally responds well. The child recovers quickly from the disease when it is taken care of early enough. Kawasaki disease is not contagiousnor hereditary. 

In rare cases, Kawasaki disease can lead to certain cardiovascular complications : 

• Dilation of the arteries;
• Heart valve abnormalities (murmur);
• Heart rhythm disturbances (arrhythmia);
• Damage to the muscle wall of the heart (myocarditis);
• Damage to the membrane of the heart (pericarditis).

Reminder of the symptoms and risks of coronavirus in children

According to the Ped-Covid study, led by the Necker hospital (AP-HP) and the Institut Pasteur, children are not very symptomatic in nearly 70% of cases. The study concerns 775 children aged 0 to 18. On the other hand, the characteristic signs observed in children are fever accompanied by unusual irritability, cough, diarrhea sometimes associated with vomiting and abdominal cramps. Cases of severe form of Covid-19 disease are exceptional in children. The signs that should alert are breathing difficulty, cyanosis (bluish skin) or acute respiratory distress. The child will make complaints and refuse to feed. 

At the beginning of the Covid-19 epidemic, the children seemed very little affected by the new coronavirus. It’s always like that. In reality, children can be infected with Covid-19, but are not very symptomatic, or even have no symptoms at all. This is why it is difficult to take them into account in epidemiological data. In addition, it means that they can transmit the virus. As to symptoms of the novel coronavirus, they are the same in adults and children. These are clinical signs similar to those of a cold or the flu.

The second confinement and the children

Following Emmanuel Macron’s announcements, the French population is confined for the second time, from October 30 and at least until December 1. However, the school is maintained (from kindergarten to high school) and the nurseries remain open, with a reinforced health protocol. Wearing a mask is now compulsory for children from the age of 6, at school. On the other hand, as during the first confinement, each citizen must bring a derogatory travel certificate. The difference is that a permanent proof of schooling is available for the parents’ trips, between the home and the place of reception of the child. 

Back to school and coronavirus

In addition, hygiene measures are scrupulously respected, thanks to hand washing carried out several times a day and daily disinfection of the surfaces and equipment used. Strict rules have been dictated, such as the wearing of masks by all adults without exception inside and outside establishments. Students aged 6 must also wear the mask, under these same conditions. Recommendations on the “student mixingAre issued to prevent groups from crossing paths. In the canteen, the distance of 1 meter between each student must be respected.

A confirmed link between PIMS and Covid-19

Before the start of the pandemic linked to the Sars-Cov-2 virus, scientists had made the connection, during virological studies, between children and presenting Kawasaki-like symptoms and coronaviruses (different from Covid-19). The infectious agent was found in 7% of patients with the disease. The following observation is established: “Their presence does not point to them as a direct cause of the disease but, however, they can be considered to trigger an inappropriate inflammatory response in presumably predisposed children”, according to the vasculitis association. It turns out today that the cases of children reported were suffering from PIMS, for pediatric multisystem inflammatory syndromes. Clinical signs of PIMS are very close to those of Kawasaki disease. The difference is that the PIMS would affect slightly older children more, while Kawasaki disease affects very young children and babies. The cardiac lesions caused by PIMS are said to be more intense than for the rare disease.

In the report of June 16, 2020, of the 125 children initially hospitalized for PIMS, 65 of them were tested positive for Covid-19. The link was then probable, but it had not been proven.

On December 17, 2020, Public Health France indicates in its report that “ the data collected confirm the existence of a rare multisystem inflammatory syndrome in children with frequent cardiac involvement, linked to the COVID-19 epidemic “. In fact, since March 1, 2020, Santé Publique France has set up a surveillance system for children with PIMS. Since that date, 501 cases of children have been affected in France. Almost three-quarters of them, or 77%, presented positive serology for Covid-19. Over a thousand worldwide, according to the UK’s National Health Service.

On May 16, 2020, Santé Publique France announced the death of a 9-year-old boy from Marseille. The child presented Kawasaki-like symptoms. In addition, his serology was positive in relation to Covid-19. The young patient had a “severe discomfort with cardiac arrest“, At his home, although he had been hospitalized for 7 days beforehand. He presented a “neuro-developmental co-morbidity“. The clinical signs, similar to those of the rare disease, would appear about 4 weeks after a child has come into contact with the new coronavirus. 

What treatment for these small patients? 

In France, after the peak observed during the week of April 27 to May 3, the number of new cases has fallen sharply since. 

If in doubt, contact the doctor. After a diagnosis, he will give a treatment adapted to the child and will decide on the actions to be taken. Generally, the child must be hospitalized to ensure follow-up and thus avoid the risk of complications. Drug treatment will be administered to him. Tests will be ordered, such as ultrasound, to learn more about the child’s state of health. The younger body’s body is quite receptive and recovers fairly quickly. Under good conditions of follow-up, the child recovers. 

Reminder of good behavioral practices

To fight against the spread of the Sars-Cov-2 virus, we must act in prevention to protect the most vulnerable. UNICEF (United Nations Children’s Fund) recommends that parents speak clearly about the virus, through creative workshops or using simple words. You have to be patient and an educator. Hygiene measures should be observed, such as washing your hands regularly or sneezing into the crease of the elbow. To reassure children who are going back to school, parents must be aware that children will not suffer intellectual retardation. All the children are in the same situation. Explaining her emotions, being honest with her child is better than lying to her trying to reassure her. Otherwise, he will feel his parents’ anxieties and in turn be anxious about going back to school. The child must also be able to express himself and understand what is happening. He will be more inclined to respect the rules, to protect himself and his comrades.