Related articles: Smallpox
Definition
Smallpox is a highly contagious disease caused by an Orthopoxvirus. The World Health Organization (WHO) has declared the natural infection eradicated: no case of smallpox has occurred since 1977, due to vaccination applied worldwide. Today, the main epidemiological concern is linked to bioterrorism.
Contagion may occur due to inhalation of contaminated saliva droplets or direct contact with infected people.
The virus penetrates the respiratory tract or the oropharyngeal mucosa and multiplies in the regional lymph nodes and in the blood, leading to viremia.
Most common symptoms and signs *
- Ankylosis
- Asthenia
- Cachexia
- Occurrence in waves of small red itchy little spots - on the head, on the face, on the trunk and on the limbs - which over time evolve into small blisters and then into crusts destined to fall.
- Abdominal pain
- Muscle pains
- Erythema
- Rash
- Temperature
- Freckles
- macules
- Backache
- Headache
- Meningitis
- papules
- thrombocytopenia
- itch
- Pustules
- Skin Ulcers
- blisters
- He retched
- xanthomas
Further indications
After an incubation of 7-17 days, the first symptoms begin: fever, headache, low back pain and general malaise. Sometimes, abdominal pain and vomiting may occur. Smallpox also manifests itself with a characteristic maculo-papular exanthematic eruption, which appears on the face and arms before spreading rapidly to the trunk and legs. The oropharyngeal mucosa is also affected by rapidly ulcerated lesions. After 1-2 days, the skin lesions evolve in later stages becoming first vesicular, then pustular. After 8 or 9 days, the pustules become scabs, which fall leaving serious crater-like scars. The other organs are rarely involved except the central nervous system (encephalitis may develop).
The diagnosis is confirmed by the presence of the genetic material of the smallpox virus, by PCR, electron microscopy or viral culture, in the material scraped from the skin lesions. Smallpox causes death in about 30% of cases; death that occurs due to the massive inflammatory response, responsible for shock and multi-organ failure.
Treatment is generally supportive.
