A study published in the Journal of Infectious Diseases has found that pregnant women who are unvaccinated for the Delta COVID-19 variant have a higher risk of fetal death. The research was conducted by scientists at Johns Hopkins University, and their findings suggest that pregnant women should be vaccinated against this variant to protect their unborn babies.
As of now, no vaccine protects against Delta COVID-19, a strain of the coronavirus that causes severe illness in humans. In 2013, researchers identified this virus as a cause of severe respiratory illnesses resulting from Middle East Respiratory Syndrome coronavirus MERS-CoV. At least 327 cases have been confirmed of which 203 ended in death.
Despite this fact, around one-third (30%) of the world’s countries don’t include protection against Delta COVID-19 in their annual vaccination schedule. This includes 52% of European countries. Many vaccines that are used to protect against other coronaviruses fail to provide complete protection against COVID-19.
There are currently no vaccines or effective antivirals that can be used to treat patients infected with this virus, says Professor Christian Drosten, Director of the University Hospital in Bonn and Vice-Chair at the German Center for Infection Research. The identification of an emerging pathogen capable of causing severe disease is always very worrying, he says.
Drosten and his colleagues at the Institute for Infectious Diseases Institut für Infektiologie in Bonn conducted a systematic review of all published literature on infections caused by Delta COVID-19 to determine how many cases there were and under what circumstances patients became ill. According to their data, there have been at least 80 cases reported from 18 countries, with 27 of these being fatal. Many cases have been reported from the Middle East and South Asia.
In our study, we found that only a fraction of the patients infected with Delta COVID-19 had mutations in either of two proteins known to inhibit the immune response NS1 and VP35. This suggests that Delta COVID-19 is particularly harmful, as viruses containing these mutations are known to cause more severe disease, says Drosten.
The results of this study support the hypothesis that previous immunity against other coronaviruses decreases protection against Delta COVID-19, which means it’s even more important for people to be vaccinated against Delta COVID-19.
The researchers also found that some patients had an unusually high level of virus in their blood, suggesting that if we can develop a treatment for this pattern of infection it may reduce the death rate of Delta COVID-19 coronavirus infections.