COVID-19 in the context of "Workplace hazard controls for COVID-19"

Shortness of breath (SOB), known as dyspnea (in AmE) or dyspnoea (in BrE), is an uncomfortable feeling of not being able to breathe well enough. The American Thoracic Society defines it as "a subjective experience of breathing discomfort that consists of qualitatively distinct sensations that vary in intensity", and recommends evaluating dyspnea by assessing the intensity of its distinct sensations, the degree of distress and discomfort involved, and its burden or impact on the patient's activities of daily living. Distinct sensations include effort/work to breathe, chest tightness or pain, and "air hunger" (the feeling of not enough oxygen). The tripod position is often assumed to be a sign.

Dyspnea is a normal symptom of heavy physical exertion but becomes pathological if it occurs in unexpected situations, when resting or during light exertion. In 85% of cases it is due to asthma, pneumonia, reflux/LPR, cardiac ischemia, COVID-19, interstitial lung disease, congestive heart failure, chronic obstructive pulmonary disease, or psychogenic causes, such as panic disorder and anxiety (see Psychogenic disease and Psychogenic pain). The best treatment to relieve or even remove shortness of breath typically depends on the underlying cause.

Vitamin C (also known as ascorbic acid and ascorbate) is a water-soluble vitamin found in citrus and other fruits, berries and vegetables. It is also a generic prescription medication and in some countries is sold as a non-prescription dietary supplement. As a therapy, it is used to prevent and treat scurvy, a disease caused by vitamin C deficiency.

Vitamin C is an essential nutrient involved in the repair of tissue, the formation of collagen, and the enzymatic production of certain neurotransmitters. It is required for the functioning of several enzymes and is important for immune system function. It also functions as an antioxidant. Vitamin C may be taken by mouth or by intramuscular, subcutaneous or intravenous injection. Various health claims exist on the supposition that moderate vitamin C deficiency increases disease risk, such as for the common cold, cancer or COVID-19. There are also claims of benefits from vitamin C supplementation in excess of the recommended dietary intake for people who are not considered vitamin C deficient. Vitamin C is generally well tolerated. Large doses may cause gastrointestinal discomfort, headache, trouble sleeping, and flushing of the skin. The United States National Academy of Medicine recommends against consuming large amounts.

Severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) is a coronavirus that causes COVID-19, the respiratory illness responsible for the COVID-19 pandemic that began in late 2019. The virus previously had the provisional name 2019 novel coronavirus (2019-nCoV), and has also been called human coronavirus 2019 (HCoV-19 or hCoV-19). First identified in the city of Wuhan, Hubei, China, the World Health Organization designated the outbreak a public health emergency of international concern from January 30, 2020, to May 5, 2023. SARS‑CoV‑2 is a positive-sense single-stranded RNA virus that is contagious in humans.

SARS‑CoV‑2 is a virus of the species Betacoronavirus pandemicum (SARSr-CoV), as is SARS-CoV-1, the virus that caused the 2002–2004 SARS outbreak. Some animal-borne coronaviruses are more closely related to SARS-CoV-2 than SARS-CoV-1 is. The closest known relative is the BANAL-52 bat coronavirus. SARS-CoV-2 is of zoonotic origin; its close genetic similarity to bat coronaviruses suggests it emerged from such a bat-borne virus. Research is ongoing as to whether SARS‑CoV‑2 came directly from bats or indirectly through any intermediate hosts. The virus shows little genetic diversity, indicating that the spillover event introducing SARS‑CoV‑2 to humans is likely to have occurred in late 2019.

This is a general overview and status of places affected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus which causes coronavirus disease 2019 (COVID-19) and is responsible for the COVID-19 pandemic. The first human cases of COVID-19 were identified in Wuhan, the capital of the province of Hubei in China in December 2019. It spread to other areas of Asia, and then worldwide in early 2020.

The figures presented are based on reported cases and deaths. While in several high-income countries the ratio of total estimated cases and deaths to reported cases and deaths is low and close to 1, for some countries it may be more than 10 or even more than 100. Implementation of COVID-19 surveillance methods varies widely.

The symptoms of COVID-19 are variable depending on the type of variant contracted, ranging from mild symptoms to a potentially fatal illness. Common symptoms include coughing, fever, loss of smell and taste, with less common ones including headaches, nasal congestion and runny nose, muscle pain, sore throat, diarrhea, eye irritation, and toes swelling or turning purple, and in moderate to severe cases, breathing difficulties. People with the COVID-19 infection may have different symptoms, and their symptoms may change over time.

Three common clusters of symptoms have been identified: a respiratory symptom cluster with cough, sputum, shortness of breath, and fever; a musculoskeletal symptom cluster with muscle and joint pain, headache, and fatigue; and a cluster of digestive symptoms with abdominal pain, vomiting, and diarrhea. In people without prior ear, nose, or throat disorders, loss of taste combined with loss of smell is associated with COVID-19 and is reported in as many as 88% of symptomatic cases.

Variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are viruses that, while similar to the original, have genetic changes that are of enough significance to lead virologists to label them separately. SARS-CoV-2 is the virus that causes coronavirus disease 2019 (COVID-19). Some have been stated to be of particular importance, due to their potential for increased transmissibility, increased virulence, or reduced effectiveness of vaccines against them. These variants contribute to the continued circulation of SARS-CoV-2.

As of 25 June 2025, the variants of interest as specified by the World Health Organization are JN.1, and the variants under monitoring are KP.3, KP.3.1.1, JN.1.18, LP.8.1, NB.1.8.1, XEC and XFG.

A COVID‑19 vaccine is a vaccine intended to provide acquired immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID‑19).

Knowledge about the structure and function of previous coronaviruses causing diseases like severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) accelerated the development of various vaccine platforms in early 2020. In 2020, the first COVID‑19 vaccines were developed and made available to the public through emergency authorizations and conditional approvals. However, immunity from the vaccines wanes over time, requiring people to get booster doses of the vaccine to maintain protection against COVID‑19.

As of 12 August 2024, 13.53 billion COVID-19 vaccine doses have been administered worldwide, with 70.6 percent of the global population having received at least one dose. While 4.19 million vaccines were then being administered daily, only 22.3 percent of people in low-income countries had received at least a first vaccine by September 2022, according to official reports from national health agencies, which are collated by Our World in Data.

During a pandemic on the rapid timeline and scale of COVID-19 cases in 2020, international organizations like the World Health Organization (WHO) and Coalition for Epidemic Preparedness Innovations (CEPI), vaccine developers, governments, and industry evaluated the distribution of the eventual vaccine(s). Individual countries producing a vaccine may be persuaded to favor the highest bidder for manufacturing or provide first-class service to their own country. Experts emphasize that licensed vaccines should be available and affordable for people at the frontlines of healthcare and in most need.

COVID-19 drug development is the research process to develop preventative therapeutic prescription drugs that would alleviate the severity of coronavirus disease 2019 (COVID-19). From early 2020 through 2021, several hundred drug companies, biotechnology firms, university research groups, and health organizations were developing therapeutic candidates for COVID-19 disease in various stages of preclinical or clinical research (506 total candidates in April 2021), with 419 potential COVID-19 drugs in clinical trials, as of April 2021.

As early as March 2020, the World Health Organization (WHO), European Medicines Agency (EMA), US Food and Drug Administration (FDA), and the Chinese government and drug manufacturers were coordinating with academic and industry researchers to speed development of vaccines, antiviral drugs, and post-infection therapies. The International Clinical Trials Registry Platform of the WHO recorded 536 clinical studies to develop post-infection therapies for COVID-19 infections, with numerous established antiviral compounds for treating other infections under clinical research to be repurposed.