As more people around the world test positive for the novel coronavirus, public health organizations are learning more about how the illness affects different people.

The Centers for Disease Control and Prevention has released new guidelines for people at a higher risk of getting very sick. While the organization advises avoiding crowds, it does not advise vulnerable individuals to completely quarantine themselves.

Who is most vulnerable to coronavirus?

According to the CDC, the following groups are at a higher risk of getting very sick from coronavirus:

Older adults.

People who have serious chronic medical conditions like heart disease, diabetes and lung disease.

The World Health Organization also listed individuals with high blood pressure and cancer as being at a higher risk of developing severe illness.

The CDC recommends that anyone belonging to these groups take extra precautions in avoiding coronavirus.

Does coronavirus affect pregnant women?

The CDC states that it does not have information yet available from published scientific reports about the suceptibiity of pregnant women to COVID-19. However, "pregnant women experience immunologic and physiologic changes which might make them more susceptible to viral respiratory infections, including COVID-19."

The CDC said it is also not yet known whether a pregnant woman can transmit the virus that causes COVID-19 to her fetus before or during delivery.

What are the symptoms of coronavirus?

COVID-19 symptoms can include fever, tiredness, dry cough and shortness of breath. Some patients may have aches, nasal congestion, runny nose, sore throat or diarrhea.

Symptoms may appear two to 14 days after exposure. The World Health Organization stated that symptoms most commonly appear at about five days after exposure.

What to do if you're at a higher risk

Those vulnerable should try to stock up on important medication or switch to a mail-order system to assure they have needed medicines if they are quarantined for a long span of time.

The CDC also recommends vulnerable populations stock up on groceries and necessary household items in case of a quarantine.

Vulnerable people should clean and disinfect their homes, particularly frequently-touched surfaces like doorknobs, light switches and faucets.

They should stay home as much as possible if the virus is spreading around their community.

MORE ABOUT CORONAVIRUS: Where the virus is now in AZ, symptoms, travel safety

Reach the reporter at Lily.Altavena@ArizonaRepublic.com or follow her on Twitter @LilyAlta.

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