IMMUNOLOGY

Detailed explanation-1: -The variola virus causes smallpox. In the past, people spread smallpox most commonly through direct, prolonged face-to-face contact with others. When they sneezed or coughed, they would send respiratory particles through the air. When other people inhaled these large droplets, they would become infected.

Detailed explanation-2: -Smallpox patients became contagious once the first sores appeared in their mouth and throat (early rash stage). They spread the virus when they coughed or sneezed and droplets from their nose or mouth spread to other people.

Detailed explanation-3: -Human-to-human transmission of variola virus occurs by inhalation of large, virus-containing airborne droplets of saliva from an infected person. Infectious virus particles are released from the sloughing off of oropharyngeal lesions.

Detailed explanation-4: -Smallpox is spread through prolonged face-to-face contact via droplets expelled from the patient’s nose and mouth, usually by coughing. Smallpox may also be transmitted through contact with materials from smallpox pustules or scabs.

Detailed explanation-5: -Historians trace the global spread of smallpox to the growth of civilizations and exploration. Expanding trade routes over the centuries also led to the spread of the disease.

Detailed explanation-6: -Smallpox is widespread in India. Arab expansion spreads smallpox into northern Africa, Spain, and Portugal. Smallpox goddess Shitala Mata, worshipped in northern India, was considered both the cause and cure of smallpox disease. Smallpox spreads to Asia Minor, the area of present-day Turkey.

Detailed explanation-7: -Smallpox is caused by the variola virus. The virus can spread: Directly from person to person. You can catch the smallpox virus by being around someone who has it.