(Reuters). A South African study has shown that Omicron coronavirus-infected people have fewer hospitalizations and more severe illnesses than the Delta virus variant. But, some of the reason for this may be due to increased immunity.

Omicron’s virulence is at the center of political and scientific debate in several countries. Governments are trying to figure out how to deal with the spreading variant, while scientists race to find the answer.

New study that hasn’t been peer reviewed sought to determine the severity and impact of Omicron and Delta infections by comparing Omicron data from October and November with Delta data, both in South Africa.

An analysis of the data was performed by scientists from the National Institute for Communicable Diseases and universities like University of KwaZulu-Natal.

Data were sourced from four sources. These included data from national COVID-19 cases reported to the NICD and data from one of the large private sector labs. Genome data was also used to analyze clinical specimens from both private and public diagnostic laboratories across the country.

According to the authors, the Omicron infection reduced the likelihood of being admitted to hospital by around 80% compared with Delta. The risk of serious illness was also lower in those who were in hospital.

These caveats cautioned that one should not jump to any conclusions regarding Omicron’s inherent characteristics.

They wrote that it was difficult to determine the contribution of the high level of immunity in the past population versus the intrinsically lower virulence of the observed lower severity of disease.

Paul Hunter from Britain’s University of East Anglia was a Professor of Medicine and described the South African study in a positive light. It is the first pre-printable study on Omicron versus Delta severity.

Hunter claimed that Omicron data from one time was its biggest weakness. He said it could not compare Delta data from a previous period to Omicron data.

He said that Omicron cases were more likely to be admitted to hospital than Delta cases. However, it was not known if this difference in virus virulence is to blame or if this could have been due to an increase in immunity to the disease in November.

This doesn’t really matter for the patient because they only want to be healthy. It is vital to be able to understand the possible pressures that health services will face.

A major Imperial College London study released its results last week. It showed that Omicron had no signs of being milder than Delta. But, there is still very little data about hospitalisations. The study hasn’t been peer-reviewed and is not yet published in a medical journal.