World Malaria Day (WMD) is an international observance commemorated every year on 25 April and recognizes global efforts to control malaria. Globally, 3.3 billion people in 106 countries are at risk of malaria. In 2012, malaria caused an estimated 627,000 deaths, mostly among African children. Asia, Latin America, and to a lesser extent the Middle East and parts of Europe are also affected.

On this day, April 12, in 1961, a citizen of the Soviet Union, Major Yuri Gagarin by spaceship "Vostok" for the first time in the world made orbital flight of the Earth, opening the era of manned space flights. He made one turn around the Earth that continued 108 minutes.

The development of manned flights is in stages with the progress of scientific and technological results and new scientific, economic and technical problems. From the first manned spacecraft and space stations to multi-purpose space manned orbital complex - this is the way traversed by the Soviet manned space flights.

Cosmonautics Bright successes - the natural result of selfless work of many thousands of people, dozens of labor groups, who do all they can for the progress of the space industry.

According to the decision of the International Aeronautical Federation the April, 12 is the International Day of Aviation and Cosmonautics.

In Ukraine, this day is called the Day of the space industry of Ukraine and fixed by Presidential Decree ? 230/97of March 13, 1997, respectively, its celebration is held every year on April 12.

The International Day for Monuments and Sites(World Heritage Day) is held on 18 April each year around the world with different types of activities, including visits to monuments and heritage sites, conferences, round tables and newspaper articles

World Day For Animals In Laboratories (also known as World Lab Animal Day) is observed every year on 24 April. The surrounding week has come to be known as "World Week for Animals In Laboratories". The National Anti-Vivisection Society (NAVS) describe the day as an "international day of commemoration" for animals in laboratories.

Ambedkar Jayanti or Bhim Jayanti is an annual festival observed on 14 April to commemorate the memory of B. R. Ambedkar. It marks Ambedkar's birthday in 1891 and since 2015 is an official public holiday throughout India. Dr. Ambedkar Jayanti is celebrated not only in India but also more than in 65 countries.

International Dance Day was introduced in 1982 by the International Dance Council (CID, Conseil International de la Danse), a UNESCO partner NGO, and is celebrated yearly, on April 29. The date is not linked to a particular person or a particular form of dance, although it's also the day when the French dancer and ballet master Jean-Georges Noverre was born. The main purpose of Dance Day events is to attract the attention of the wider public to the art of dance. Emphasis should be given to addressing a new public, people who do not follow dance events during the course of the year.

The Jallianwala Bagh massacre, also known as the Amritsar massacre, took place on 13 April 1919 when a crowd of nonviolent protesters, along with Baishakhi pilgrims, who had gathered in Jallianwala Bagh, Amritsar, Punjab, were fired upon by troops of the British Indian Army under the command of Colonel Reginald Dyer. The civilians, in the majority Sikhs, had assembled to participate in the annual Baisakhi celebrations, a religious and cultural festival for Punjabi people and also to condemn the arrest and deportation of two national leaders, Satya Pal and Dr Saifuddin Kitchlew. Coming from outside the city, they may have been unaware of the imposition of martial law.

7th April celebrated as World Health Day.

World Book Day or World Book and Copyright Day (also known as International Day of the Book or World Book Days) is a yearly event on April 23rd, organized by the United Nations Educational, Scientific and Cultural Organization (UNESCO), to promote reading, publishing and copyright. In the United Kingdom, the day is recognized on the first Thursday in March. World Book Day was celebrated for the first time on 23 April 1995.

World Haemophilia Day celebrated on 17th April.