About one in five people with COVID-19 are also infected with other respiratory viruses, according to a preliminary analysis led by Ian Brown, MD, a clinical associate professor of emergency medicine at the Stanford School of Medicine.
In addition, the analysis found that about one in 10 people who exhibit symptoms of respiratory illness at an emergency department, and who are subsequently diagnosed with a common respiratory virus, are co-infected with the COVID-19 virus.
The findings challenge the assumption that people are unlikely to have COVID-19 if they have another type of viral respiratory disease.
“Currently, if a patient tests positive for a different respiratory virus, we believe that they don’t have COVID-19,” said Nigam Shah, MBBS, Ph.D., associate professor of medicine and of biomedical data science at the medical school.
“However, given the co-infection rates we’ve observed in this sample, that is an incorrect assumption.”
Accurate and rapid testing for SARS-CoV-2, the virus that causes COVID-19, is necessary to identify those who are infected and slow the spread of the disease. Understanding the likelihood of co-infection is an important step in this process.
“Hospitals don’t have unlimited access to COVID testing,” Brown said . “In some cases, a patient with respiratory symptoms may first be tested for a non-COVID virus.
If there is a diagnosis of influenza or rhinovirus, or other respiratory virus, a hospital may discharge the patient without COVID testing, concluding that the alternative diagnosis is the reason for the symptoms.”
Brown and his colleagues analyzed 562 people recently tested for COVID-19 at Stanford Health Care’s Marc and Laura Andreessen Emergency Department. Forty-nine of those people tested positive for infection with SARS-CoV-2.
Of the 562 people, 517 were also tested for the presence of other common respiratory viruses, such as influenza A and B, respiratory syncytial virus, rhinovirus, adenovirus and several types of pneumonia.
One hundred and twenty seven received a positive result for one of these other respiratory viruses.
Of the people tested for both SARS-CoV-2 and other respiratory viruses, eleven people—or about 22% of the 49 confirmed COVID-19 cases and 8.7% of the 127 people with other respiratory viruses—were found to be co-infected with both kinds of viruses.
The researchers shared their findings March 18 on Medium.com, an online publishing platform, at the request of the California Department of Public Health.
As of March 29, there have been 136,880 confirmed or presumptive cases of COVID-19 in the United States, and 2,409 deaths resulting from the illness, according to the Coronavirus Resource Center at Johns Hopkins University.
More than 33,500 people worldwide have died from the disease, which causes mild to severe respiratory illness. The disease is particularly dangerous for elderly people and those with pre-existing health conditions, including heart disease, diabetes and lung disease.
With the ongoing outbreak of Coronavirus Disease 2019 (COVID-19), infected patients within and beyond the epidemic area, Wuhan, China, showed different epidemiological and clinical characteristics. There is a paucity of data concerning coinfection with other common respiratory pathogens in COVID-19 patients outside of Wuhan.
Methods: We conducted a double-centre study recruiting 68 patients with severe acute respiratory coronavirus 2 (SARS-CoV-2) infection confirmed by nucleic acid testing in Qingdao and Wuhan from January 17 to February 16, 2020.
Indirect immunofluorescence was performed to detect the specific IgM antibody against common respiratory pathogens in collected acute phase serum. Results: Of the 68 patients with SARS-CoV-2 infection, 30 (44.12%) were from Qingdao.
The median age of Qingdao and Wuhan patients were 50 (IQR: 37-59) and 31 (IQR: 28-38) years, respectively, and the majority of patients were female in Qingdao (60.00%) and Wuhan (55.26%).
Among COVID-19 patients in Qingdao, 24 (80.00%) of them had IgM antibodies against at least one respiratory pathogen, whereas only one (2.63%) of the patients in Wuhan had positive results for serum IgM antibody detection (P<0.0001).
The most common respiratory pathogens detected in Qingdao COVID-19 patients were influenza virus A (60.00%) and influenza virus B (53.33%), followed by mycoplasma pneumoniae (23.33%) and legionella pneumophila (20.00%).
While the pattern for coinfection in patients with community-acquired pneumonia in Qingdao was quite different, with a positive rate of only 20.90%. Interpretation: We reported a large proportion of COVID-19 patients with coinfection of seasonal respiratory pathogens in Qingdao, northeast China, which differed greatly from the patients in Wuhan, central China.
Precautions are needed when dealing with COVID-19 patients beyond the epidemic centre who have coinfection with other respiratory pathogens.
We highly recommend adding SARS-CoV-2 to routine diagnostic testing in capable hospitals to prevent misdetection of the virus.
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More information: Higher co-infection rates in COVID19. medium.com/@nigam/higher-co-in … covid19-b24965088333