The worldwide COVID-19 pandemic involves information that is continually evolving and being updated as public health officials and scientists collect more data and develop an understanding of the virus. Health professionals should check this page and other respected websites for the latest information.

The most current evidence shows the virus transmits easily between people, most often through droplets generated by coughs and sneezes. Part of the idea of social distancing is that droplets can generally carry for only 5 to 6 feet. If you’re farther than that, your chances of getting the virus are generally lower.

COVID-19 may also be spread by people who are not showing symptoms (i.e., “asymptomatic”). The disease might be transmitted when people touch a contaminated surface or object and then touch their face, nose or mouth or eyes. However, this is not thought to be the main way the virus spreads. Current data and information also suggest that the risk of COVID-19 spreading from pets to people is low as well.

No matter the risk of transmission, rigorous hand hygiene and optimal cleaning practices at home and in public settings helps guard against the transmission of COVID-19.

A recent summary of the latest data by the CDC shows that about two-thirds of the COVID-19 transmissions in the U.S. come from people not showing symptoms – either because their cases are asymptomatic or pre-symptomatic. According to the CDC, this “underscores the importance of social distancing, including the avoidance of congregate settings, to reduce COVID-19 spread.”

Diagnostic error is always a concern. Missing a diagnosis for COVID-19 could lead to delayed treatment or a preventable COVID-19 transmission. Just as importantly, other health issues can be missed when the focus is narrowed to COVID-19, according to research by two UC Davis Health patient safety experts, as noted in this PSNet primer.

Review of COVID-19 Testing MethodsLaboratory Best Practice Blog from UC Davis Health 

We continue to watch daily the rate of new infections, and the number of patients in the hospital (at UC Davis Medical Center and other regional medical centers), for signs of increase that could be an early warning for a potential patient surge. The state and county health departments are also keeping track of COVID-19 cases and watching for signs of a potential surge in COVID-19 patients. Working with other hospitals and our local public health departments, and with our own in-house testing capabilities, we should be able to quickly recognize the kind of increasing trend lines that would be early indicators of a possible surge in COVID-19 patients requiring hospitalization.

For COVID-19 specimen collection and handling, please fill out this request form

Most healthy people who become infected with COVID-19 have no symptoms or have mild symptoms. However, there have been healthy people who have progressed to severe disease. We must be vigilant regardless of age and underlying illness. People who have underlying illness and who are older are at higher risk for getting severe disease, but they’re not the only ones at risk.

Procedures that release upper and lower respiratory tract specimens into the air are at higher risk for releasing airborne particulates by aerosolization. These procedures include intubation, BiPAP, high-flow nasal cannula, nebulizing medications, CPR and resuscitation and bronchoscopy. During these aerosol-generating procedures, providers should wear PAPR or an N95 mask as well as eye protection, a gown, and gloves. If available, it is preferred that the procedure be conducted in an airborne isolation room or private room, and personnel should be limited.

Based on updated guidance from the CDC (July 17), the criteria for health care providers (HCP) returning to work is as follows:

Data doesn't support a test-based strategy to determine when staff can return to work. Instead, the criteria is a symptom-based strategy for those who test positive and are symptomatic, and a time-based strategy for those who test positive but are asymptomatic. In addition, the time-based strategy for returning to work has been expanded from 10 days to 20 days.

For the symptomatic HCP with suspected or confirmed COVID-19, use the symptom-based strategy and do not return to work until:

  • At least 24 hours have passed since recovery, defined as resolution of fever without the use of fever-reducing medications and improvement in respiratory symptoms (e.g., cough, shortness of breath); and
  • At least 20 days have passed since symptoms first appeared

For the HCP who is asymptomatic with laboratory-confirmed COVID-19, and who has not had any symptoms, use the time-based strategy and do not return to work until:

  • 20 days have passed since the date of the first positive COVID-19 diagnostic test, assuming HCP has not subsequently developed symptoms since their positive test. If they develop symptoms, then the symptom-based or test-based strategy should be used.

Visit the CDC website for additional return-to-work information.

Protection for health professionals

Contact droplet is the predominant route of COVID-19 transmission. Using appropriate contact droplet precautions, and in the circumstance where the patient can be masked, you increase the potential protection. If aerosolization is expected, then you should upgrade to N95 or PAPR-level protection. Since surfaces are lower risk but not zero risk of virus transmission, good hand hygiene, as well as keeping hands away from your face and appropriate housekeeping within the health care facility are still the best ways to protect against COVID-19 transmission.

In every location, all employees need to either maintain at least 6 feet of distance from other people at all times, or wear a mask. In clinical areas where 6 feet of space between people cannot be maintained, clinical masks (ear loop/procedure masks) need to be worn. In non-clinical areas, employees should stay 6 feet apart at all times, or there should be a barrier in place (example: cubicle walls), or a face covering needs to be worn. In non-clinical areas, these masks can be cloth or homemade (with no logos).

This is in alignment with California Gov. Gavin Newsom’s direction on April 14 to ensure our actions are aligned to achieve the following:

  • Ensure our ability to care for the sick within our hospitals;
  • Prevent infection in people who are at high risk for severe disease;
  • Build the capacity to protect the health and well-being of the public; and
  • Reduce social, emotional and economic disruptions

There have been no employee infections from patients at UC Davis Health when proper personal protective equipment (PPE) was worn. Transmission of infection from patients to employees have resulted from not properly wearing a face mask, face shield or improper hand hygiene (or, not wearing higher level protection during aerosol-generating procedures (AGPs) for COVID-positive patients In addition, UC Davis Health’s Stuart Cohen published a paper as a co-author on this topic:

“In all 8 cases, the staff had close contact with the index patients without sufficient PPE. Importantly, despite multiple aerosol generating procedures, there was no evidence of airborne transmission.

“These observations suggest that, at least in a health care setting, a majority of SARS-CoV-2 transmission is likely to take place during close contact with infected patients through respiratory droplets, rather than by long-distance airborne transmission.”

Evidence shows wearing a face shield along with a mask provides more protection from COVID-19. Face shields are required for all providers managed by UC Davis Health during patient encounters (inpatient and outpatient), and they're recommended by the CDC. The primary protection from a face shield is in close environments, when droplets can be sprayed (via speaking, sneezing, coughing) from person to person. Secondary protection comes from a reduction in the wearer’s hands touching the eyes or areas around the eye, which can transfer the virus and cause an infection. Face shields should cover the forehead, extend below the chin, and wrap around the side of the face, according to CDC guidelines.

For patients where no aerosol-generating procedures are expected, use contact and droplet precautions. Providers should use a surgical mask, eye protection (e.g. face shield), gown, and gloves.