COVID-19 is on the rise in California and across the Western and Southern border, a sign that the virus may be starting its seasonal growth spurt.
The US Centers for Disease Control and Prevention estimates that COVID is on the rise in California, Texas, Florida, Missouri, Alabama, Oregon, Utah, Nevada, New Mexico and Hawaii. The rates of COVID-19 in those states — measured by the share of emergency room visits attributable to COVID — remain very low, the CDC said.
Other data points also suggest that COVID is on the rise.
“Covid-19 activity has been steadily increasing throughout California based on testing practices. The concentration of contaminated water is also increasing,” according to Grant Boyken, a spokesman for the California Department of Public Health.
In the week ending July 18, 3.4% of COVID tests in California came back positive. That's lower than at the same time two years ago, but still an increase from last month, when the test failure rate was 1.15%.
According to health officials and experts, it would not be surprising if the summer outbreak of COVID started now. A large number of people have not been sick with COVID for a long time.
“We expect many people to get sick,” said Dr. Peter Chin-Hong.
COVID is on the rise across the West and South, according to the US Centers for Disease Control and Prevention.
(US Centers for Disease Control and Prevention)
“I hope that doesn't happen, but I think that's what we're worried about,” said Chin-Hong, an infectious disease specialist at UC San Francisco. Currently, however, UC San Francisco is not seeing many cases of COVID in its hospitals, he noted.
Kaiser is seeing a slight increase in COVID cases in the past two weeks — almost all outpatients, said Dr. Elizabeth Hudson, regional chief of infectious diseases at Kaiser Permanente Southern California.
The rate of COVID testing in LA County began to rise after the Fourth of July holiday. According to regional data, the rate was 4.28% in the week ended July 11, up from 1.52% the previous week.
“The next few weeks are going to tell us we're going to see another summer of increased COVID,” Hudson said.
Test success rates are also increasing in Orange County, with 3% of COVID tests coming back positive in the week ending July 11, up from 1.3% the previous month.
In Northern California, the detection of contaminated water and the rate of testing for COVID are highest in San Francisco, said the city's Department of Public Health. The levels of coronavirus in wastewater in San José and Palo Alto are considered “high,” the Santa Clara County Department of Public Health said.
“Summer outbreaks of COVID-19 have occurred every year since 2020, so we don't expect to see much activity this time,” state health officials said.
Hospitalization rates remain “very low” across California but are expected to increase in the coming weeks. “The percentage of emergency department visits and the percentage of deaths attributable to COVID-19 are both lower than levels seen during the same period” two years ago, according to the Department of Public Health.
State officials continue to recommend that all people 6 months of age and older stay up-to-date on COVID-19 vaccines. The most recent version of the COVID vaccine came out in September.
“This is especially important for people who are at high risk, such as infants and toddlers, pregnant people, the elderly, and others who are at risk of serious diseases,” said health officials.
“Some groups of people may need multiple doses and those aged 65+ or disabled need two doses six months apart. For those who have not received an updated dose or are due for their second dose, vaccination is recommended before the summer wave,” said the agency, recommending that those groups receive the current 2025-26 version of the vaccine this summer while waiting for the 272 version released in 272.
Globally, the activity of COVID was generally low and stable in the last week of June, according to the World Health Organization, although there was a high activity or increase in parts of Latin America, northern Europe, parts of Africa and Southeast Asia.
Health officials in Taiwan reported an increase in COVID activity there, and were monitoring the spread of the virus in Japan, South Korea, Hong Kong and China, according to the island's Central News Agency. Medical providers in Taiwan were reporting some kind of problems with patients coming down with COVID and seasonal flu; infections are expected to increase significantly in mid-August, local media reported.
COVID has gotten worse since the early years of the pandemic, when the virus was new to humanity and there were no vaccines or drugs to treat those who were sick. COVID-19 was the third leading cause of death in the US in 2020 and 2021, the fourth leading cause in 2022, and the 10th leading cause in 2023.
In 2020, there were 385,676 deaths involving COVID nationwide; in 2021, 463,267 deaths; in 2022, 247,168 deaths; in 2023, 76,055 deaths; in 2024, 47,541 deaths; and in 2025, 20,685 people died, according to the CDC website.
That's still a huge death toll, experts say, and the virus can still lead to the development of chronic COVID-19 and other health problems.
The hope is that the summer COVID surge will continue to be weaker than last summer. But even so, the disease will still cause suffering and death to some victims, according to Chin-Hong.
Doctors say that those who are at particular risk of severe COVID are the elderly, people with weakened immune systems, pregnant women and those under the age of 5, especially children.
“We've seen millions of waves of COVID, but the children haven't,” Chin-Hong said.
“I think we have to protect the most vulnerable,” she said. It's especially important for high-risk groups to get a new vaccine for COVID at least once a year, Chin-Hong said.
People who are sick with COVID should also remember that, if they are diagnosed early, for many there is an option to ask for drugs to reduce the length and severity of the illness, such as Paxlovid.
“If you're over 65 or younger but at high risk for complications — eg, you have diabetes, heart disease, obesity, asthma or a weakened immune system for other reasons such as cancer — you can get a COVID-19 booster now,” Hudson said. “This will help you avoid getting COVID-19 now during what could be another summer surgery.”
