In a study, scientists observed the displacement and imbalance of good bacteria in the throats of COVID-infected people after viral clearance. The researchers discovered that the response to the antibiotics (Azithromycin and Doxycycline) was not uniform among all COVID-infected individuals, as some showed a decrease in the proportion of harmful bacteria, while the trend was reversed for others, particularly those who had a very low proportion of harmful bacteria at the start.

The one-of-its-kind study was conducted by scientists from the Regional Medical Research Centre (RMRC), an ICMR laboratory and KIIT School of Biotechnology in Bhubaneswar, and the National Institute of Biomedical Genomics in Kalyani in West Bengal. Dr. Debdutta Bhattacharya, a senior scientist at RMRC, stated that the study included 30 samples, of which 20 were of Covid-infected patients. He added that on Day 1 itself, they observed a striking contrast in the human oropharyngeal microbiome (HOPM) of infected individuals compared to uninfected people.

In the study, they found that the ratio of certain bacteria that have been linked to lung pneumonia in several model organisms and human autopsies was elevated in some cases. Hence, the research team concluded that the posterior segment of the oropharyngeal microbiome is a key reservoir for bacteria causing pneumonia and chronic lung infection in SARS-CoV-2 infection. 

(Source: https://www.newindianexpress.com/cities/bhubaneswar/2022/sep/07/study-finds-microbiome-imbalance-in-coronavirus-recovered-patients-2495692.html )