COVID-19 (SARS-CoV-2)

Primary reference(s)

WHO, 2023. Coronavirus disease (COVID-19). World Health Organization (WHO). Accessed 29 May 2025.

WHO Euro, no date. Coronavirus disease (COVID-19) pandemic. World Health Organization Regional Office for Europe (WHO Euro). Accessed 28 May 2025.

Annotations

Key relevant UN convention / multilateral treaty

International Health Regulations (2005), 3rd ed. (WHO, 2016).

Drivers

COVID-19 is the disease caused by the SARS-CoV-2 coronavirus. It usually spreads between people in close contact (WHO, 2023a). Cases of novel coronavirus (nCoV) were first detected in China in December 2019, with the virus spreading rapidly to other countries across the world (WHO Euro, 2025).

WHO reports that the virus spreads mainly between people who are in close contact with each other, for example at a conversational distance when they cough, sneeze, speak, sing or breathe (short-range airborne transmission) or droplet transmission. The virus can also spread in poorly ventilated and/or crowded indoor settings, where people tend to spend longer periods of time with the virus suspended in the air or travel farther than conversational distance (long-range airborne transmission). Infection can also spread through touching the eyes, nose or mouth after touching surfaces or objects that have been contaminated by the virus (WHO, 2021a).

Impacts

Cases of novel coronavirus (nCoV) were first detected in China in December 2019, with the virus spreading rapidly to other countries across the world which led WHO to declare a Public Health Emergency of International Concern (PHEIC) on 30 January 2020 (WHO Euro, 2025). 

People with the following symptoms were requested to seek immediate medical attention: difficulty breathing, especially at rest, or unable to speak in sentences, confusion, drowsiness or loss of consciousness, persistent pain or pressure in the chest, skin being cold or clammy, or turning pale or a bluish colour and loss of speech or movement (WHO, 2023a). 

People who have pre-existing health problems are at higher risk when they have COVID-19; 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 (WHO, 2023a). In rare situations, children can develop severe inflammatory syndrome a few weeks after infection (WHO, 2023a). 

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 (WHO, 2023a). 

As of 30 March 2025, 777,691,501 COVID-19 cases had been reported to WHO with 7,093,267 COVID-19 deaths (WHO, 2025a).   

Nearly five years since the first SARS-CoV-2 infections were reported, the global COVID-19 situation has changed substantially. With widespread immunity from both vaccination and prior infection, currently circulating variants are now associated with lower severe disease rates and fewer hospitalizations. As a result, most countries have lifted public health and social measures and have moved to end their national COVID-19 emergencies (WHO, 2023b). 

COVID-19 continues to circulate widely, however, presenting significant challenges to health systems worldwide. Tens of thousands of people are infected or re-infected with SARS-CoV-2 each week. It is vital that countries sustain the public health response to COVID-19 amid ongoing illness and death and the emergence of SARS-CoV-2 variants, adapting it to the requirements based on the current COVID-19 situation and risk (WHO, 2023b). 

In 2022 and 2023, WHO released a package of policy briefs designed to help countries formulate policies to manage SARS-CoV-2 transmission, particularly in high-risk and vulnerable populations, and to reduce morbidity, mortality and long-term sequelae from COVID-19. The policy briefs have been updated to reflect the current COVID-19 situation and risk and the approaches outlined in the September 2023 WHO document Ending the COVID-19 emergency and transitioning from emergency phase to longer-term disease management: Guidance on calibrating the response and the Director-General’s standing recommendations for COVID-19 (WHO, 2023b).

Multi-hazard context

From one of the many reports on the impact of COVID-10, the Independent Panel for Pandemic Preparedness & Response COVID-19: Make it the Last Pandemic. was published in 2021 and presented at the UN General Assembly in a special session. As of April 2021, they reported that COVID-19 has shown how an infectious disease can sweep the globe in weeks and, in the space of a few months, set back sustainable development by years (Independent Panel, 2021). By all measures, the impact of the pandemic is massive as of 28 April 2021. They summarised the data as the numbers who were infected by the virus and the deaths reported in 223 countries, territories and areas, with the impact on health workers mortality and the economic impacts. They also reported that at its highest point in 2020, 90% of schoolchildren were unable to attend school with 10 million more girls at risk of early marriage because of the pandemic (Independent Panel, 2021). They noted that gender-based violence support services have seen fivefold increases in demand. The authors were concerned it was probable that 115–125 million people have been pushed into extreme poverty (Independent Panel, 2021).

Risk Management

To prevent the spread of COVID-19 (WHO, 2023a): 

• avoid crowds and keep a safe distance from others, even if they don’t appear to be sick;
• wear a properly fitted mask if you feel sick, have been close to people who are sick, if you are at high risk, or in crowded or poorly ventilated areas;
• clean your hands frequently with alcohol-based hand rub or soap and water;
• cover your mouth and nose with a bent elbow or tissue when you cough or sneeze;
• dispose of used tissues right away and clean your hands; and 
• if you develop symptoms or test positive for COVID-19, self-isolate until you recover. 

COVID-19 vaccines provide strong protection against serious illness, hospitalization and death. 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 (WHO, 2023a). 

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 (WHO, 2023a). 

WHO 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 its partners, has supported the fastest, most coordinated, and most 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 (WHO, 2023a). 

As many countries discontinue COVID-19-specific reporting and integrate it into respiratory disease surveillance, WHO will use all available sources to continue monitoring the COVID-19 epidemiological situation, especially data on illness and impact on health systems. COVID-19 remains a major threat, and WHO urges Member States to maintain, not dismantle, their established COVID-19 infrastructure. It is crucial to sustain early warning, surveillance and reporting, variant tracking, early clinical care provision, administration of vaccine to high-risk groups, improvements in ventilation, and regular communication. As of February 2025, WHO continued to monitor several SARS-CoV-2 variants, including one variant of interest (VOI) JN.1, and seven variants under monitoring (VUMs). JN.1, the VOI, accounted for 15.0% of sequences in week 1 of 2025. The VUM, XEC and LP.8.1 continue to increase in prevalence, accounting for 44.8% and 4.7%, respectively, of sequences in week 1 of 2025, and are the only tracked variants currently growing in prevalence. All the remaining VUMs are declining in prevalence (WHO, 2025c).

Monitoring

The section and the table below offer an overview of monitoring for COVID-19. This information can be used for forecasting within a national early warning system (EWS). Since EWS capacities and processes differ across countries, the most current and specific information regarding EWS should be obtained from the appropriate national or regional agency/authority responsible for disaster management.

Under the implementation of the International Health Regulations (IHR), countries were advised to sustain collaborative surveillance for COVID-19, in order to provide a basis for situational awareness and risk assessment and the detection of significant changes in virus characteristics, virus spread, disease severity and population immunity, as per the standing recommendations for COVID-19 issued by the WHO Director-General (WHO, 2024).

Core surveillance activities for SARS-CoV-2 provide early warnings of changes in epidemiological patterns, monitor circulation and the emergence of new SARS-CoV-2 variants and enable monitoring of both morbidity and mortality trends and disease burden on health care capacities (health and care workers, hospitalizations and intensive care unit admissions) (WHO, 2024).

These activities also measure the longer-term impacts of Post-COVID conditions (also known as Long COVID). Incorporating strategic and geographically representative genomic surveillance enables the monitoring of the circulation of SARS-CoV-2 variants of concern (VOCs), early detection of new variants of interest (VOIs) and tracking of SARS-CoV-2 in potential animal reservoirs, along with other changes in virological patterns (WHO, 2024).

WHO supports countries to conduct all-hazards strategic risk assessment in the contexts of health emergencies and disasters, which results in the development of a country's risk profile. Empowered with the country risk profile, inclusive of a seasonal risk calendar, countries can anticipate potential emergencies before they occur to trigger early alerts and inform early actions (WHO, 2021b).

WHO's Early Warning, Alert and Response System (EWARS) has been designed to improve disease outbreak detection in emergency settings, such as in countries in conflict or following a disaster from natural hazards. It is a simple and cost-effective way to rapidly set up a disease surveillance system. EWARS is deployed during an emergency as an adjunct to the national disease surveillance system. WHO works with Ministries of Health and health sector partners to train local health workers to use the system. After the emergency, EWARS should re-integrate back into the national system (WHO, 2023c).