Throughout the past decade, the world has faced numerous epidemics that have exhausted health and economic systems. Some of these are still affecting us today, and the world is racing to use all means to control them and protect humanity from their consequences. The following report highlights the most famous viruses that have caused thousands of deaths worldwide, supported by information directly from the World Health Organization.
1) **H1N1 Virus (Swine Flu)**
The H1N1 virus was discovered in 2009 in Mexico before spreading to many countries, particularly the United States. The World Health Organization highlighted that swine flu is one of the most dangerous viruses due to its ability to change rapidly, with minor mutations occurring every two to three years. The organization reported that the virus caused the deaths of 18,000 people in 2010. Infection occurs through contact with infected pigs, their environments, or close contact with infected individuals in small groups.
2) **Ebola Virus**
The World Health Organization clarified that the Ebola virus causes a severe disease, often leading to death if not treated. The virus is transmitted from wildlife to humans and spreads among human populations through direct contact from person to person. The virus re-emerged in Guinea in 2013, spreading to Liberia and Sierra Leone, causing the deaths of 6,000 people within a year of its reappearance. When it re-emerged again in 2018 in the Democratic Republic of the Congo, it resulted in 2,200 deaths. Fruit bats of the family Pteropodidae are believed to be the natural hosts of the Ebola virus. The virus spreads to human populations through contact with the blood, fluids, or tissues of infected animals like chimpanzees, gorillas, fruit bats, monkeys, forest antelopes, and porcupines that are found sick or dead in rainforests.
3) **MERS Coronavirus**
According to the World Health Organization, the coronavirus that causes Middle East Respiratory Syndrome (MERS) is of animal origin and is transmitted from animals to humans. It was first discovered in Saudi Arabia in 2012. Typical symptoms of MERS include fever, cough, and difficulty breathing, with pneumonia being common. Gastrointestinal symptoms, including diarrhea, have also been reported. Severe cases can result in respiratory failure, requiring artificial ventilation and support in intensive care. Approximately 36% of reported MERS patients have died.
4) **Zika Virus**
The World Health Organization stated that Zika virus disease is primarily transmitted through mosquitoes that bite humans during the day. This virus was first discovered in monkeys in Uganda in 1947, and then in humans in 1952 in Tanzania. Symptoms of the disease include high fever, rash with conjunctivitis, joint pain, and headaches, lasting between two to seven days. Zika virus infection during pregnancy can lead to babies being born with microcephaly and other congenital malformations known as "congenital Zika syndrome," as well as complications during pregnancy like premature birth and miscarriage. There is an increasing risk of Zika virus infection causing neurological complications in adults and children, such as Guillain-Barré syndrome, neuropathies, and myelitis. The virus spread to French Polynesia in 2013 and other Pacific countries. Brazil reported a significant outbreak of rash disease in 2015, quickly identified as Zika virus infection. Cases have been reported across the Americas, Africa, and other regions, with 86 countries reporting cases so far.
5) **Novel Coronavirus (COVID-19)**
The novel coronavirus was discovered in 2019 in the Chinese city of Wuhan through a wildlife market. Since then, the virus spread rapidly among citizens during the New Year holiday and across neighboring countries, quickly spreading worldwide and becoming a global pandemic affecting humanity as a whole. Most people infected with COVID-19 experience mild to moderate respiratory illness and recover without needing special treatment. Older adults and those with underlying medical conditions such as cardiovascular diseases, diabetes, chronic respiratory diseases, and cancer are at higher risk for serious illness. The world continues to discover new complications and symptoms of the virus as it evolves, with 167 million reported cases and 3.47 million deaths worldwide to date.
