(ANSA) - ROME, MAY 12 - Two common viruses of the herpes group can increase the risk of developing type 2 diabetes in infected subjects.
This is what emerges from a research published in the journal Diabetologia and conducted by Tim Woelfled of the Ludwig-Maximilians and Helmholtz University of Munich.
Herpes are among the most common viruses in humans, with currently known optotypes: herpes simplex virus (HSV) 1 and 2, varicella-zoster virus (VZV), Epstein-Barr virus (EBV), cytomegalovirus (CMV) and human herpesviruses (HHVs) 6, 7 and 8. All cause infections that remain dormant for life after the initial primary infection, which is usually mild or asymptomatic.
Type 2 diabetes or insulin resistance is estimated to affect 9.3% of the world population.
Obesity, a sedentary lifestyle and smoking are certainly among the known risk factors.
But recently the possibility has arisen that some infections may also contribute to an increased risk of getting sick.
The research was based on the health data of 1967 individuals.
Participants underwent medical examinations between 2006-2008 and again between 2013-2014, including tests for the presence of herpes virus, blood glucose, and measurement of glycated hemoglobin (a long-term blood glucose control measurement).
Diabetes was present in 8.5% of the participants at the start of the study and in 14.6% at the time of follow-up.
Of the 1257 volunteers with normal glucose tolerance at the start, 364 developed prediabetes and 17 developed diabetes during the 6.5-year monitoring period.
Blood tests at the start of the study found that Epstein-Barr virus (the mononucleosis virus) was the most common herpesvirus, with 98% of the sample positive, followed by HSV1 (88%), HHV7 (85%) , VZV (79%), CMV (46%), HHV6 (39%) and HSV2 (11%).
Participants were positive for an average of 4.4 herpesviruses at start and 4.7 at follow-up.
It was found that those with HSV2 were 59% more likely to develop pre-diabetes than those with seronegative, while CMV infection was associated with a 33% increase in the incidence of pre-diabetes.
The study found that both HSV2 and CMV contributed to the development of pre-diabetes, even after taking into account all other known risk factors for diabetes.
HSV2 was also associated with worse levels of glycated hemoglobin.
The mechanisms by which these viruses could contribute to the development of diabetes remain to be discovered.
Both HSV2 and CMV cause chronic infections that could modulate the immune system by stimulating or suppressing its activity, which in turn can affect the function of the endocrine (hormonal) system.
"These data confirm the possibility that there is a link between viral infection and diabetes, and suggest how viral infection (probably by potentiating the 'activation' of inflammation mechanisms associated with obesity and diabetes predisposition) may 'unmask' (ie emerge) the disease in predisposed subjects "- comments Agostino Consoli, of the University of Chieti-Pescara and President of the Italian Society of Diabetology-.
"It is also a fact that emerged from the analysis of subjects who develop Long-Covid: even in these individuals, in fact, an increase in the incidence of diabetes was observed", he continues.
"Further research evaluating viral prevention strategies for public health, possibly including the development of effective vaccines against herpesviruses, is, in the light of these data, even more necessary," the experts conclude.
(HANDLE).
