World AIDS Vaccine Day (WAVD) was observed on _____ ?

1) May 21
2) May 18
3) May 19
4) May 17

Explanation:
Since 1998, World AIDS Vaccine Day (WAVD) is observed every year on 18th May to spread awareness about the urgent need for a vaccine to prevent Human Immunodeficiency Virus (HIV) infection and Acquired Immuno Deficiency Syndrome (AIDS). The day is also known as HIV Vaccine Awareness Day. World AIDS Vaccine Day observance is headed by National Institute of Allergy and Infectious Disease (NIAID), Washington DC, USA.In 1981, AIDS was first reported in the United States and since then becomes a worldwide epidemic.HIV originated in west-central Africa during the late 19th or early 20th century.