CDC updates coronavirus guidelines to recognize airborne spread

The coronavirus disease (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is still actively spreading across the globe. The case toll sits at over 31 million infections, and over 960,000 lives lost.

Early on in the pandemic, it was thought that the virus was only spread via respiratory droplets. However, scientific research soon showed it also to be an airborne virus. Now, the U.S. Centers for Disease Control and Prevention (CDC) has updated its guideline, acknowledging that the virus can hang in the air, fueling its spread.

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COVID-19 airborne spread

After the World Health Organization (WHO) acknowledged that SARS-CoV-2 could spread through the air in July 2020, the CDC also updated its guidelines for infection prevention. The health agency noted that COVID-19 most commonly spreads between people who are in close contact with each other, within six feet, and through respiratory droplets or small particles, such as those in aerosols, produced when an infected person sneezes, coughs, speaks, breathes, and sings.

Further, SARS-CoV-2 in droplets and aerosols, can be inhaled through the mouth and nose, pass through airways, and reach the lungs, causing infection. Apart from inhaling these droplets, the virus can also spread through contact with droplets that land on surfaces and objects, which can be transferred by touch. When people touch surfaces with the infected droplets, such as doorknobs, handles, and tables, it can cause infection when they also touch their mouth, nose, or eyes.

Airborne transmission may ensue when droplets from an infected person hang in the air and are inhaled by other people. This may occur in closed areas, crowded places, and areas with poor ventilation.

“There is growing evidence that droplets and airborne particles can remain suspended in the air and be breathed in by others, and travel distances beyond 6 feet (for example, during choir practice, in restaurants, or fitness classes). In general, indoor environments without good ventilation increase this risk,” the CDC said.

The CDC also emphasized how easily the virus can spread from one person to another. SARS-CoV-2 is considered one of the most contagious viral infections, which can quickly spread, more so than influenza. Overall, the virus can be more infectious when an infected person interacts more closely with others over long periods.

The potential for the animal to human transmission of SARS-CoV-2 has also now been recognized by the CDC. However, that risk is considered very low; some cases of people-to-animal transmissions have been recorded. In some situations, the transmission is possible, including infections from dogs and cats. The CDC says, “At this time, there is no evidence that animals play a significant role in spreading the virus that causes COVID-19. Based on the limited information available to date, the risk of animals spreading COVID-19 to people is considered to be low.”

Protecting oneself

Previously, CDC suggested maintaining a social distance of about six feet, regularly disinfecting surfaces, proper hand hygiene, and covering the mouth and nose with a mask when out in public or around others. Now, the agency adds additional recommendations that people stay home and isolate themselves from others when sick. Use air purifiers to help reduce airborne germs in indoor spaces.

“The best way to prevent illness is to avoid being exposed to this virus. You can take steps to slow the spread,” the CDC emphasized.

Aside from these infection preventive measures, the CDC also recommended to maintain social connections and for people to tend to their mental health.

Global spread

Amid the pandemic, many countries have now re-opened to help boost their economies, heavily impacted by the spreading disease. Along with the lifting of restrictions, many cases are being reported across countries, with the United States still reporting the highest number of cases.

The U.S. has more than 6.8 million cases and nearly 200,000 deaths. Meanwhile, India and Brazil follow with more than 5.48 and 4.54 million cases, respectively. Brazil has more than 136,000 deaths, while India reports more than 87,000 deaths.

Russia, Colombia, and Peru report more than 1 million, 768,000, and 765,000 cases. China has reported over 90,000 cases and 4,737 death.