Pertussis vaccine and new mutations in the pathogen that existing vaccines are unable to effectively control. Some studies have suggested that while acellular pertussis vaccines are effective at preventing the disease, they have a limited impact on infection and transmission, meaning that vaccinated people could spread the disease even though they may have only mild symptoms or none at all. For children, immunizations are commonly given in combination with immunizations against tetanus, diphtheria, polio, and haemophilus influenzae type B at two, four, six, and 15–18 months of age. A single later booster is given at four to six years of age (US
Meleda disease It may be caused by a mutation on the "SLURP1" gene, located on chromosome 8. Meleda disease Meleda disease (MDM) or "mal de Meleda", also called Mljet disease, keratosis palmoplantaris and transgradiens of Siemens, (also known as "acral keratoderma", "mutilating palmoplantar keratoderma of the Gamborg-Nielsen type", "palmoplantar ectodermal dysplasia type VIII", and "palmoplantar keratoderma of the Norrbotten type") is an extremely rare autosomal recessive congenital skin disorder in which dry, thick patches of skin develop on the soles of the hands and feet, a condition known as palmoplantar hyperkeratosis. MDM is most common on the Dalmatian island of Mljet (or