There are six different types of COVID infections, finds study
COVID-19 cases have breached the 18 million mark globally and there's still a lot that remains unknown about the spread of the viral infection. Since it is a novel coronavirus, scientists are still trying to figure out as to why the infection impacts people differently. While many tend to suffer from a milder form of infection, some belonging to higher-risk categories carry a more severe risk, whereas others tend to be asymptomatic. Nonetheless, the same strain of the virus can leave lasting impacts on people, even after they have recovered.
While we still continue to battle the surge and might as well adapt and learn to live with the virus, a recent study done by King's College, London, has now found out that even though there is just a single virus which is wreaking havoc the world over, there are six different types of infections observed in people.
Symptoms in the first week could determine spread and severity of infection
The study
A study was conducted amongst 1600 patients across the UK and the US, who recorded COVID-19 symptoms between the months of March and April. Since most patients tend to visit a hospital only much later, the patients were asked to reveal details of the symptoms they suffered in the first 8-10 days of infection.
According to the sampling, three clusters were found to belong to the mild category, while three belonged to the more severe category and more likely to impact those older, or with pre-existing medical conditions.
In order of severity, six main clusters of infections which could be identified were. The symptom highlighted in bold were the most defining and peculiar of a particular cluster:
Cluster 1: Flu-like infection, with no fever
Cluster 2: Flu-like infection, with the presence of fever
Cluster 3: Gastrointestinal infection
Cluster 4: Severe level 1, with fatigue
Cluster 5: Severe level 2, with confusion
Cluster 6: Severe level 3, with abdominal and respiratory distress
What do we know so far
The symptoms described in the six clusters can give us a lot of inferences as to how COVID-19 impacts different brackets of people and provides a lookout for the kind of symptoms to expect. Of all patients, headaches were persistent in all groups, which faded away after 3-4 days barring the last two similar groups.
Sense of smell was something which kicked in patients only after the 4th day post infection. Analysis suggests that the difference in the severity of infection could only be observed after 4-5 days of infection.
Who requires hospitalization?
While patients belonging to the mild or moderate cluster were unlikely to record a symptom such as fatigue in the first week, for patients in the severe or high-risk category, some of the critical symptoms were observed on the start of Day 1 itself. Some of these symptoms included breathlessness, fatigue and abdominal pain.
The researchers said that the analysis pointed that people belonging to clusters 4, 5 or 6 tended to be older and frailer, and were more likely to be overweight and have pre-existing conditions such as diabetes or lung disease than those with type 1, 2 or 3. It was discovered that only 1.5% of people with cluster 1, 4.4% of people with cluster 2 and 3.3% of people with cluster 3 required breathing support, considered to be a mark of degradation of the disease.
Identifying clusters could possibly prevent the second wave, save lives
The study done by King's College is yet to be peer-reviewed or published. However, identifying the clusters can make people realize how crucial monitoring symptoms are and provide priority care to those who might need it more than others and administer right tools to prevent a second wave in some countries.
The parameters and specific symptoms could also prove to be a breakthrough and help doctors determine who is at most risk, take timely treatment decisions and save lives. Doctor Carole Sudre, the study’s lead researcher, in a statement, said:
“Our study illustrates the importance of monitoring symptoms over time to make our predictions about individual risk and outcomes more sophisticated and accurate. This approach is helping us to understand the unfolding story of this disease in each patient so they can get the best care.”