COVID-19 Update

This report is updated daily by 9:30 a.m. and reflects activity through the previous day. 


COVID-19 Activity

The first chart to the right shows the total of all COVID-19 activity since the beginning of the pandemic in Napa County, the State of California, the United States, and the World. The chart below shows current COVID-19 in Napa County, both active investigations and the cumulative number since the start of the COVID-19 pandemic.

Cases are people who have tested positive for COVID-19.  Public Health staff investigate individuals who may be experiencing symptoms that are compatible with COVID-19, especially individuals who are at higher risk for poor outcomes and individuals in high-risk occupations, such as healthcare. A Person Under Investigation is someone with symptoms of COVID-19 who has met the criteria for prioritized testing, but has not been confirmed to be a case. Contacts to cases are people with a known exposure to a confirmed case of COVID-19.

COVID-19 Testing

The number above includes all tests conducted in Napa County. Persons Under Investigation (PUI) and symptomatic travelers and close contacts to patients were tested. Some patients were tested more than once, especially early on in the outbreak.

In order to be tested for COVID-19, people with fever and respiratory symptoms must have an order for lab testing placed through their doctor’s office. This means that the doctor will use a screening form to determine if COVID-19 testing is indicated. People who are symptomatic and have been exposed to a COVID-19 case, had recent travel to an area with community spread, will be considered for testing. Due to the limited number of tests, testing must be prioritized for high-risk settings and patients, including healthcare workers, people aged 65 and older and others at high risk of severe illness, and residents in congregate care settings, such as a skilled nursing facilities. If a test is ordered and it is approved by Public Health using the criteria mentioned above, the patient will then be contacted by public health and given instructions on how to obtain a test at the drive through clinic. The drive through clinic is currently by appointment only.

Influenza-like Respiratory Outbreaks

What is an outbreak?

An outbreak is a sudden increase in occurrences of a disease in a particular time and place. Influenza is a major cause of respiratory outbreaks, but these outbreaks can also be caused by other viruses such as respiratory syncytial virus (RSV), which is a common respiratory virus that usually causes mild, cold-like symptoms. Influenza-like respiratory disease outbreaks can affect a small group (two or more people) or impact an entire community. 

What is the situation in Napa County?

Listed below is a summary of influenza-like respiratory outbreaks reported in Napa County:

Total (Year-to-date): 11

Under Investigation: 2

Closed: 9

The chart to the right shows that several respiratory diseases are circulating in Napa including seasonal flu and RSV. Most outbreaks have been confirmed by laboratory testing or through a doctor(s) diagnosis. None of the outbreaks have been identified as COVID-19.

Influenza-Like Symptom Emergency Department Poll

What is Syndromic Surveillance and Why are We Polling Hospital Emergency Departments?

The Influenza-Like Illness (ILI) poll is part of Napa County's syndromic surveillance strategy to rapidly detect diseases, including COVID-19, before waiting for a formal diagnosis from a healthcare provider. Through this system, the County can monitor and assess the impact of ILI on our community and help inform resource and mitigation decisions. In this poll, patients are considered to have Influenza-Like Illness (ILI) if they have a fever and cough, sore throat and/or shortness of breath. 

What is the situation in Napa County? 

 The chart to the right shows the percent of patients seen at local hospitals with influenza-like illness each day. In the last week, the average percent of patients seen in hospital EDs with flu like symptoms was 3%. The proportion of patients seen in the EDs with flu like illness falls within expected the range of normal seasonal influenza activity. The peak for the current seasonal flu season was 7.1% and over the last 5 years the highest weekly average was 10.4% 

The majority of patients seen at the hospitals were aged 0-4 and 25-64 (31% each), followed by ages 65+ (23%) and ages 5-24 (15%). In comparison, the populations most at risk for developing seasonal flu complications are children younger than age 5 and adults older than 65. 

*Technical note: Fluctuations in daily levels may be due to the small number of people seen at hospitals on a daily basis.

What are Seasonal Influenza Trends?

The chart below shows the weekly average percent of patients seen at QVMC ED with seasonal influenza-like illness for the last three influenza seasons. Seasonal influenza season begins in October (week 40) and to May. Over the last three seasons weekly figures ranged from 0% to 9.3%.