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What is Covid-19?
What is Covid-19?
Covid-19 is a respiratory illness caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The virus is thought to spread mainly between people who are in close contact with one another (within about 6 feet) through respiratory droplets produced when an infected person coughs or sneezes.
It is also possible that a person can get COVID-19 by touching a surface or object that has the virus on it and then touching their own mouth, nose, or eyes. For more information go to CDC’s Fact Sheet- How to protect yourself and Others.
Risk of infection with COVID-19 is higher for people who are in close contact with someone known to have COVID-19, such as healthcare workers, direct support providers, and household members. Other people at higher risk for infection are those who live or have recently been in an area with ongoing spread of COVID-19.
Key Points from the CDC
All COVID-19 vaccines currently authorized in the United States are effective against COVID-19, including serious outcomes like severe disease, hospitalization, and death.
Available evidence suggests the currently authorized mRNA COVID-19 vaccines (Pfizer-BioNTech and Moderna) provide protection against a variety of strains, including B.1.1.7 (originally identified in the United Kingdom) and B.1.351 (originally identified in South Africa). Other vaccines show reduced efficacy against B.1.351 but may still protect against severe disease. Continued monitoring of vaccine effectiveness against variants is needed.
A growing body of evidence indicates that people fully vaccinated with an mRNA vaccine (Pfizer-BioNTech and Moderna) are less likely to have asymptomatic infection or to transmit SARS-CoV-2 to others. Studies are underway to learn more about the benefits of Johnson & Johnson/Janssen vaccine. However, the risk for SARS-CoV-2 infection in fully vaccinated people cannot be completely eliminated as long as there is continued community transmission of the virus.
At this time, there are limited data on vaccine effectiveness in people who are immunocompromised. People with immunocompromising conditions, including those taking immunosuppressive medications, should discuss the need for personal protective measures after vaccination with their healthcare provider.
This updated science brief synthesizes the scientific evidence supporting CDC’s guidance for fully vaccinated people and will continue to be updated as more information becomes available.
Infectious Rates of Major Diseases
A major concern right now is Delta, a highly contagious (and possibly more severe) SARS-CoV-2 virus strain, which was first identified in India in December. It then swept rapidly through that country and Great Britain as well, which has led to rising numbers of infections and deaths. The first Delta case in the United States was diagnosed a couple of months ago (in March) and it is now the dominant strain in the U.S.
Delta is more contagious than the other virus strains.
Unvaccinated people are at risk.
Delta could lead to 'hyperlocal outbreaks.'
There is still more to learn about Delta.
Vaccination is the best protection against Delta.
Coronavirus Disease 2019 (COVID-19)
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus responsible for a disease outbreak that originated in China in late 2019. The official name of the disease caused by the virus is coronavirus disease 2019, or COVID-19.