Coronavirus disease (COVID-19) – World Health Organization

COVID-19 is the disease caused by the SARS-CoV-2 coronavirus. It usually spreads between people in close contact.
COVID-19 vaccines provide strong protection against severe illness and death. Although a person can still get COVID-19 after vaccination, they are more likely to have mild or no symptoms.
Anyone can get sick with COVID-19 and become seriously ill or die, but most people will recover without treatment.
People over age 60 and those with existing medical conditions have a higher risk of getting seriously ill. These conditions include high blood pressure, diabetes, obesity, immunosuppression including HIV, cancer and pregnancy. Unvaccinated people also have a higher risk of severe symptoms. 

People may experience different symptoms from COVID-19. Symptoms usually begin 5–6 days after exposure and last 1–14 days.
The most common symptoms are:
Less common symptoms are:
People with the following symptoms should seek immediate medical attention:
People who have pre-existing health problems are at higher risk when they have COVID-19; they should seek medical help early if worried about their condition. These include people taking immunosuppressive medication; those with chronic heart, lung, liver or rheumatological problems; those with HIV, diabetes, cancer. obesity or dementia.
People with severe disease and those needing hospital treatment should receive treatment as soon as possible. The consequences of severe COVID-19 include death, respiratory failure, sepsis, thromboembolism (blood clots), and multiorgan failure, including injury of the heart, liver or kidneys.
In rare situations, children can develop a severe inflammatory syndrome a few weeks after infection. 
Some people who have had COVID-19, whether they have needed hospitalization or not, continue to experience symptoms. These long-term effects are called long COVID (or post COVID-19 condition). The most common symptoms associated with long COVID include fatigue, breathlessness and cognitive dysfunction (for example, confusion, forgetfulness, or a lack of mental focus or clarity). Long COVID can affect a person’s ability to perform daily activities such as work or household chores.  
Most people will recover without needing treatment in a hospital.
For those who need it, doctors will suggest treatments for COVID-19 based on the severity of the disease and the risk of it getting worse. They will consider the person’s age and if they have other health problems.
More on treatment
People should get vaccinated as soon as it’s their turn. They should follow local guidance on vaccination and ways to protect themselves against COVID-19.
COVID-19 vaccines provide strong protection against serious illness, hospitalization and death.
To prevent the spread of COVID-19:
Vaccination against COVID-19 is based on priority groups such as people aged 60 years and over, and those with underlying medical problems such as high blood pressure, diabetes, chronic health problems, immunosuppression (including HIV), obesity, cancer, pregnant persons, and unvaccinated people. In March 2023, WHO updated its recommendations on primary series vaccination (two doses of any vaccine) as well as the need for booster doses. These recommendations are time-limited and can change at any time depending on how the SARS-CoV-2 virus is circulating in your area or country. It is important to stay up to date with local guidelines and recommendations provided by your local health authority.
Since its introduction, COVID-19 vaccines have saved millions of lives across the world by providing protection against severe disease, hospitalization, and death. Even though vaccines protect against severe disease and death, it is still possible to spread SARS-CoV-2 to others after being vaccinated.
The World Health Organization is the global coordinating agency for the response to the COVID-19 pandemic. The Organization works with Member States and partners on all aspects of the pandemic response, including facilitating research, developing guidance, coordinating vaccine development and distribution, and monitoring daily case numbers and trends around the world.
Since April 2020, the Access to COVID-19 Tools (ACT) Accelerator, launched by WHO and partners, has supported the fastest, most coordinated, and successful global effort in history to develop tools to fight a disease. COVAX, the vaccines pillar of the ACT-Accelerator is a ground-breaking global collaboration to accelerate the development, production, and equitable access to COVID-19 tests, treatments, and vaccines.
WHO provides global coordination and member state support on vaccine safety monitoring. It developed the target product profiles for COVID-19 vaccines and provides R&D technical coordination.
WHO also leads work to improve global capacity and access to oxygen production, distribution and supply to patients.
Although WHO announced the end of the emergency phase of COVID-19 in May 2023, the Organization continues to coordinate the global response.
Related
All information on COVID-19
WHO’s work on coronavirus disease
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