Hand, Foot, and Mouth Disease (HFMD) is a common viral illness primarily affecting infants and young children. It is most frequently caused by non-polio enteroviruses, such as Coxsackievirus A16 and Enterovirus 71. The blisters and rash are typically the most visible symptoms that prompt concern from caregivers. HFMD is generally a mild infection that resolves on its own, but the associated lesions can cause significant discomfort.
Stages of Blister Progression and Healing
The timeline for the blisters’ appearance and resolution is often the primary concern for those managing HFMD. Skin lesions begin as small, flat, red spots (macules), evolving within one to two days into small, fluid-filled blisters (vesicles). These lesions typically appear on the palms, soles of the feet, and sometimes the buttocks or groin. The entire process, from the first appearance of spots to full resolution, generally takes about 7 to 10 days.
The blisters on the hands and feet tend to dry out and fade away rather than bursting or scabbing over like chickenpox lesions. In some cases, a mild, harmless peeling of the skin may occur one or two weeks into recovery.
Mouth sores often follow a slightly different timeline and can be the most painful aspect of the illness. These painful ulcers appear on the tongue, gums, and inner cheeks, starting as red spots that quickly blister and rupture. Mouth ulcers typically begin to clear up sooner than external skin lesions, often resolving completely within five to seven days.
The severity of the blisters and the total healing time can vary depending on the specific viral strain involved. For example, some strains, such as Coxsackievirus A6, can cause a more widespread rash. Despite these variations, the lesions do not typically leave scars once they have healed.
Strategies for Managing Discomfort
Managing the pain associated with the blisters, particularly the mouth sores, is an important focus of care, as there is no specific medication to cure the viral infection. Over-the-counter pain relievers, such as acetaminophen or ibuprofen, can alleviate general discomfort and reduce fever. Caregivers should consult a healthcare provider for appropriate dosing instructions, and aspirin must be avoided in children due to the risk of Reye’s syndrome.
Painful mouth ulcers can make swallowing difficult, raising the risk of dehydration. To maintain hydration, offer cool liquids like water, milk, or diluted electrolyte solutions, which can be soothing. Soft foods requiring minimal chewing, such as yogurt, puddings, or smoothies, are best tolerated during peak mouth pain.
It is helpful to avoid acidic, salty, or spicy foods and drinks, as these can irritate open sores and increase pain. For external blisters, the main goal is preventing secondary bacterial infection. Gently cleanse the areas and prevent scratching or picking at the lesions, which could introduce bacteria.
Determining When Contagion Risk Ends
Hand, Foot, and Mouth Disease is highly contagious, and the risk of transmission is generally highest during the first week of illness. The virus spreads easily through respiratory droplets from coughing or sneezing, and contact with fluid from active blisters. The presence of fluid-filled blisters indicates a high concentration of the virus on the skin surface.
Guidelines for returning to public settings, such as school or daycare, require the child to be fever-free for at least 24 hours and well enough to participate in activities. Additionally, all weeping or fluid-filled external blisters should have dried up, crusted over, or resolved. Once lesions are no longer open, the risk of spreading the virus through blister fluid significantly decreases.
The period of viral shedding can extend beyond the resolution of visible symptoms. The virus continues to be shed in the stool for several weeks after the blisters and fever have disappeared. This prolonged shedding necessitates diligent handwashing, especially after using the restroom or changing diapers, to limit environmental spread.